@techreport{soton342629, month = {September}, type = {Project Report}, title = {Report of the 7th Meeting of CLIVAR/CliC/SCAR Southern Ocean Region Implementation Panel, 19-21 October 2011, Bolder USA}, publisher = {International CLIVAR Project Office}, year = {2012}, series = {180}, keywords = {Clivar, Climate, Southern Oceans}, url = {https://eprints.soton.ac.uk/342629/} } @techreport{soton196497, month = {September}, type = {Project Report}, title = {Report of the 6th Meeting of the CLIVAR/CliC/SCAR Southern Ocean region panel and the workshop on the upper and lower cells of the meridional circulation in the Southern Ocean, National Oceanography Centre, Southampton, UK 14 - 17th June 2010}, publisher = {International CLIVAR Project Office}, year = {2011}, series = {148}, note = {WCRP Informal Report No: 6/2011}, keywords = {CLIVAR, CliC, SCAR, southern ocean region panel, meridional circulation, southern ocean, ICPO, climate change}, url = {https://eprints.soton.ac.uk/196497/} } @techreport{soton47521, month = {June}, type = {Project Report}, title = {Report of the 4th Meeting of the CLIVAR/CliC/SCAR Southern Ocean Region Panel, 14 and 17 November 2006, Palacio San Mart{\'i}n, Ministry of Foreign Affairs, Buenos Aires, Argentina}, publisher = {International CLIVAR Project Office}, year = {2007}, series = {113}, note = {WCRP Informal Report No. 4/2007}, keywords = {CLIVAR, WCRP, CliC, SCAR, Southern Ocean, Climate Change}, url = {https://eprints.soton.ac.uk/47521/} } @techreport{soton47558, month = {October}, type = {Project Report}, title = {Report of the CLIVAR VACS Southern and Eastern African Climate Predictability Workshop, Tanzania Meteorological Agency, Dar es Salaam, 10-13th July 2006}, publisher = {International CLIVAR Project Office}, year = {2006}, series = {109}, note = {WCRP Informal Report No. 19/2006}, keywords = {CLIVAR, WCRP, VACS, Southern and Eastern Africa, Climate Predictability}, url = {https://eprints.soton.ac.uk/47558/} } @techreport{soton41424, month = {August}, type = {Project Report}, title = {Report on the WGOMD Workshop on Southern Ocean Modelling, Hobart, Australia, 9-10 November 2005}, publisher = {International CLIVAR Project Office}, year = {2006}, series = {102}, note = {WCRP Informal Report No. 7/2006}, keywords = {CLIVAR, WCRP, ocean model development, southern ocean modelling, WGOMD}, url = {https://eprints.soton.ac.uk/41424/} } @techreport{soton19361, month = {December}, type = {Project Report}, title = {Reports of the Modes of Southern Hemisphere Climate Variability Workshop (27-28 June 2005) and the Third Session of the CLIVAR/CliC/SCAR Southern Ocean Region Panel (29-30 June 2005), Cambridge, UK}, publisher = {International CLIVAR Project Office}, year = {2005}, series = {98}, note = {WCRP Informal Report No. 15/2005}, keywords = {CLIVAR, WCRP, CliC, SCAR, Southern Ocean, modes, variability}, url = {https://eprints.soton.ac.uk/19361/} } @techreport{soton18758, month = {March}, type = {Project Report}, title = {Report of the Second Session of the CLIVAR/CliC Southern Ocean Panel, Bremerhaven, Germany, 8-11 September 2003}, publisher = {International CLIVAR Project Office}, year = {2004}, series = {76}, keywords = {CLIVAR, WCRP, CliC, Southern Ocean}, url = {https://eprints.soton.ac.uk/18758/} } @techreport{soton19177, month = {August}, type = {Project Report}, title = {Report of the 1st Session of the CLIVAR/Clic Southern Ocean Panel, Hobart, Australia, March 11-13, 2002}, publisher = {International CLIVAR Project Office}, year = {2002}, series = {65}, note = {WCRP Informal Report No. 16/2002}, keywords = {CLIVAR, WCRP, CliC, Southern Ocean}, url = {https://eprints.soton.ac.uk/19177/} } @article{soton457911, volume = {192}, month = {August}, title = {Across and along-strike crustal structure variations of the western Afar margin and adjacent plateau: Insights from receiver functions analysis}, author = {Abdulhakim Ahmed and Cecile Doubre and Sylvie Leroy and Derek Keir and Carolina Pagli and James O.S. Hammond and Atalay Ayele}, year = {2022}, journal = {Journal of African Earth Sciences}, keywords = {Afar margin, Africa, Continental margin, Crustal structure, Receiver functions, Southern red sea rift}, url = {https://eprints.soton.ac.uk/457911/}, abstract = {We used teleseismic receiver function analysis to image the crustal structure beneath 24 broadband seismic stations densely deployed along two profiles traversing different structural units across the western Afar margin. Our high-resolution receiver function results image pronounced spatial variations in the crustal structure along the profiles and provide improved insights to understand how strain is partitioned in the crust during rifting. Beneath the western plateau next to northern Afar, the crust is likely felsic-to-intermediate in composition (average Vp/Vs 1.74), with a step like thinning of the crust from an average of 38 km beneath the western plateau to an average of 22 km beneath the marginal graben. Consistently thicker crust is observed beneath the southern profile (central Afar), showing four distinct regions of uniform crustal thickness: 1) an average crustal thickness of 42 km beneath the western plateau; 2) 34 km beneath the foothills area; 3) 28 km beneath the marginal graben and the wide extensional basin and 4) 21 km beneath the central rift axis. We use crustal thickness results to estimate a stretching factor {\ensuremath{\beta}} of 2.2 and 2.7 for central Afar and northern Afar respectively. Our estimated values are lower than {\ensuremath{\beta}} \> 3.0 predicted from plate reconstructions, and we interpret that the variations are best explained by 2?5 km magmatic addition into the crust. The crustal composition beneath the southern profile is more complex with elevated Vp/Vs ratios ranging between 1.79 and 1.85 beneath the western plateau and marginal graben. This is consistent with a greater mafic component and best explained by crust altered by intrusions due to significant pre and syn-rift magmatic activity. Abnormally high Vp/Vs ratios of more than 1.90 are observed beneath the axial rift zone of central Afar, which most likely suggests the localization of partial melt within the crust.} } @article{soton441295, volume = {535}, month = {April}, title = {The oceanic biogeochemistry of nickel and its isotopes: New data from the South Atlantic and the Southern Ocean biogeochemical divide}, author = {Corey Archer and Derek Vance and Angela Milne and Maeve C. Lohan}, year = {2020}, note = {Funding Information: The authors thank the chief scientist Gideon Henderson, and the captains, crews and all of the scientists on both legs of the NERC funded UK-GEOTRACES GA10 section (D357 and JC068), grant \# NE/H004475/1 to MCL. We thank Shotaro Takano and Urs Menet for their assistance in the lab. We thank Wafa Abouchami for providing some of the samples used for this work. We are also grateful to Tom Browning for fruitful discussions during the preparation of this manuscript. We are also grateful for the editorial handling of this manuscript, and the comments of two anonymous reviewers. This research was supported by ETH Z{\"u}rich and Swiss SNF grant 200020\_165904 . Publisher Copyright: {\copyright} 2020 Elsevier B.V.}, journal = {Earth and Planetary Science Letters}, keywords = {Antarctic Polar Front, GEOTRACES, Southern Ocean biogeochemistry, nickel isotopes}, url = {https://eprints.soton.ac.uk/441295/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Nickel (Ni) is important for a number of enzymes in oceanic phytoplankton. It has received less attention than some other bioactive metals because it is not reduced to extremely low dissolved concentrations in the photic zone. However, there are strong indications in previous studies that this residual pool is not bio-available. Oceanic Ni isotope data are still scarce, but have great potential for understanding this issue, as well as for understanding the Ni mass balance of the oceans now and in the past. Here, we present new concentration and isotope data for the UK GEOTRACES section at 40?S in the Atlantic (GA10). Nickel concentration data show typical nutrient-like profiles, slightly modified by variable pre-formed concentrations in sub-surface water masses, e.g. North Atlantic Deep Water. Nickel isotopes, in common with findings in previous studies, are homogeneous beneath 500 m, at about +1.3? in {\ensuremath{\delta}} {\ensuremath{<}}sup{\ensuremath{>}}60{\ensuremath{<}}/sup{\ensuremath{>}}Ni, in samples with Ni concentrations above 3-3.5 nM. The surface South Atlantic, however, has concentrations below 3 nM, and shows significantly higher {\ensuremath{\delta}} {\ensuremath{<}}sup{\ensuremath{>}}60{\ensuremath{<}}/sup{\ensuremath{>}}Ni, up to +1.74?, that are closely anti-correlated with Ni concentrations. The data for the deep South Atlantic dissolved pool, with a {\ensuremath{\delta}} {\ensuremath{<}}sup{\ensuremath{>}}60{\ensuremath{<}}/sup{\ensuremath{>}}Ni = 1.31 {$\pm$} 0.12? (average and 2SD) confirm the homogeneity of the global deep ocean, which previous data demonstrate extends all the way to the surface in the upwelling zone of the Southern Ocean south of the Polar Front. This Ni isotope composition is significantly heavier than known inputs to the oceanic dissolved pool. This mass balance requires an isotopically light sink that may be represented by sedimentary Mn-oxide associated Ni. The magnitude of the isotope fractionation implied by the upper ocean data is not consistent with plausible potential abiotic removal processes. Rather, these data are best explained by biological uptake. However, consideration of the detailed relationships between Ni concentrations and isotope compositions requires that a substantial portion of the oceanic dissolved Ni pool is not bio-available. The data are consistent either with a small preference for the light isotope during uptake (about 0.1?) or two distinct pools of dissolved Ni, one bio-available and one strongly bound in organic complexes, with limited isotopic exchange between them. Patterns of co-variation in Ni concentrations and isotopes with the major nutrients point to strong contrasts across the Polar Front of the Southern Ocean, contrasts that exhibit both similarities and differences with those for the major nutrients and other trace metal micronutrients. South of the Polar Front, Ni is taken up in modest amounts by diatoms, without isotope fractionation. North of the Polar Front the data are most consistent with cyanobacteria as the dominant control on Ni uptake, leading to significant coupled abundance and isotope variation. {\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton381289, volume = {112}, number = {42}, month = {October}, author = {R.B. Aronson and K.E. Smith and S.C. Vos and J.B. McClintock and M.O. Amsler and P.O. Moksnes and D.S. Ellis and J.W. Kaeli and H. Singh and J.W. Bailey and J.C. Schiferl and R. van Woesik and M.A. Martin and B.V. Steffel and M.E. Deal and S.M. Lazarus and J.N. Havenhand and R. Swalethorp and S. Kjellerup and S. Thatje}, title = {No barrier to emergence of bathyal king crabs on the Antarctic shelf}, journal = {Proceedings of the National Academy of Sciences}, pages = {12997--13002}, year = {2015}, keywords = {biological invasion, polar emergence, climate change, predation, Southern Ocean}, url = {https://eprints.soton.ac.uk/381289/}, abstract = {Cold-water conditions have excluded durophagous (skeleton-breaking) predators from the Antarctic seafloor for millions of years. Rapidly warming seas off the western Antarctic Peninsula (WAP) could now facilitate their return to the continental shelf, with profound consequences for the endemic fauna. Among the likely first arrivals are king crabs (Lithodidae), which were discovered recently on the adjacent continental slope. During the austral summer of 2010-2011, we used underwater imagery to survey a slope-dwelling population of the lithodid Paralomis birsteini off Marguerite Bay, WAP for environmental or trophic impediments to shoreward expansion. The average density was {\texttt{\char126}}4.5 ind?1000m{\ensuremath{<}}sup{\ensuremath{>}}-2{\ensuremath{<}}/sup{\ensuremath{>}} within a depth-range of 1100-1500 m (overall observed depth-range 841?2266 m). Evidence of juveniles, molting, and precopulatory behavior suggested a reproductively viable population on the slope. At the time of the survey, there was no thermal barrier to prevent the lithodids from expanding upward and emerging on the outer shelf (400?500 m depth); however, near-surface temperatures remained too cold for them to survive in shallow, coastal environments (\<200 m). Ambient salinity, composition of the substrate, and the depth-distribution of potential predators likewise indicated no barriers to expansion onto the outer shelf. Primary food resources for lithodids{--}echinoderms and mollusks{--}were abundant on the upper slope (500?800 m) and outer shelf. At present rates of warming, lithodids should emerge in outer-shelf environments within several decades. As sea temperatures continue to rise, they will likely play an increasingly important trophic role in subtidal communities closer to shore.} } @techreport{soton286, type = {Project Report}, title = {RRS James Clark Ross Cruise 81, 18 Dec 2002-02 Jan 2003. Drake Passage repeat hydrography: WOCE Southern Repeat Section 1b ? Elephant Island to Burdwood Bank}, author = {S Bacon}, publisher = {Southampton Oceanography Centre, University of Southampton}, year = {2003}, series = {43}, keywords = {ADCP, Antarctic Circumpolar Current, Antarctic Ocean, Acoustic Doppler Current Profiler, Cruise 81 2002-3, CTD Observations, Drake Passage, James Clark Ross, LADCP, Lowered ADCP, Southern Ocean, Vessel-Mounted ADCP, WOCE, World Ocean Circulation Experiment}, url = {https://eprints.soton.ac.uk/286/}, abstract = {This report describes the eighth repeat hydrography section across Drake Passage, first established during the World Ocean Circulation Experiment. Thirty CTD/LADCP stations were carried out across the 753 km section from Elephant Island to Burdwood Bank, plus one test station and one station at the Rothera Time Series (RaTS) site, just off Biscoe Wharf at Rothera. Maximum station spacing on the{\ensuremath{<}}br/{\ensuremath{>}}section was 33 km, with stations closer together on the continental shelves. Water samples were drawn for salinity analysis, for subsequent CTD conductivity calibration. Samples were also drawn for analysis of oxygen isotope fraction ?18O, for later analysis back at Southampton Oceanography Centre. The LADCP comprised a single downward-looking RD Instruments Workhorse ADCP. The CTD was a SeaBird 911plus with dual conductivity and temperature sensors. Various underway measurements included navigation, vessel-mounted ADCP, sea surface temperature and salinity, water depth and meteorological parameters.} } @techreport{soton244, type = {Project Report}, title = {RRS James Clark Ross Cruise 67, 19 Nov-17 Dec 2002. Drake Passage repeat hydrography: WOCE Southern Repeat Section 1b ? Burdwood Bank to Elephant Island}, author = {S. Bacon}, publisher = {Southampton Oceanography Centre, University of Southampton}, year = {2002}, series = {38}, keywords = {ADCP, Antarctic Circumpolar Current, Antarctic Ocean, Acoustic Doppler Current Profiler, CTD observations, Drake Passage, James Clark Ross, cruise 67 2001, LADCP, Lowered ADCP, Southern Ocean, Vessel Mounted ADCP, WOCE, World Ocean Circulation Experiment}, url = {https://eprints.soton.ac.uk/244/}, abstract = {This report describes the seventh repeat hydrography section across Drake Passage, first established during the World Ocean Circulation Experiment. Thirty CTD/LADCP stations were carried out across the 753 km section from Burdwood Bank to Elephant Island, plus one test station, one station in Drake Passage to provide sound speed information for concurrent geophysical activities, and one station at the Rothera Time Series (RaTS) site, just off Biscoe Wharf at Rothera. Maximum station spacing on the{\ensuremath{<}}br/{\ensuremath{>}}section was 33 km, with stations closer together on the continental shelves. Water samples were drawn for salinity analysis, for subsequent CTD conductivity calibration. The LADCP was a new 2-instrument setup comprising upward? and downward?looking RD Instruments Workhorse ADCPs. The CTD was a SeaBird 911plus with dual temperature and conductivity sensors. Various underway measurements included navigation, vessel-mounted ADCP, sea surface temperature and salinity, water depth and meteorological parameters.} } @techreport{soton14723, editor = {S. Bacon and S.A. Cunningham}, type = {Project Report}, title = {Drake Passage summary report: Cruises on RRS "James Clark Ross", 1993-2000. Drake Passage repeat hydrography: WOCE Southern Repeat Section 1b - Elephant Island to Burdwood Bank.}, publisher = {Southampton Oceanography Centre, University of Southampton}, year = {2005}, series = {44}, keywords = {ADCP, Antarctic Circumpolar Current, Antarctic Ocean, Acoustic Doppler Current Profiler, cruise 1993-2000, CTD observations, Drake Passage, James Clark Ross, LADCP, Lowered ADCP, Southern Ocean, Vessel-Mounted ADCP, WOCE, World Ocean Circulation Experiment}, url = {https://eprints.soton.ac.uk/14723/}, abstract = {This report documents five early cruises in the Drake Passage annual repeat series conducted by Southampton Oceanography Centre in collaboration with the British Antarctic Survey. The series began under the auspices of the World Ocean Circulation Experiment as southern repeat section SR1b with a SeaSoar (towed undulating profiler) occupation in 1992. We document cruises from 1993 (JR0a), 1994 (JR0b), 1996 (JR16), 1997 (JR27) and 2000 (JR47). The cruises were all hydrographic CTD sections across Drake Passage between Burdwood Bank and Elephant Island, comprising 30 stations. One cruise (JR27) was occupied at higher resolution with 52 stations; also additional chemical measurements were made. On two cruises (JR16 and JR27), a lowered acoustic Doppler current profiler (ADCP) was introduced to provide full-depth water velocity profiles. Other measurements (vessel-mounted ADCP, sample salinity, navigation, expendable athythermographs, etc.) are described in context.} } @techreport{soton208983, month = {December}, author = {S. Bacon and et al}, series = {8}, note = {New series incorporating reports from NOC Liverpool and Southampton Sites}, editor = {L. Jullion}, title = {RRS James Cook Cruise 30, 26 Dec 2008-30 Jan 2009. Antarctic Deep Water Rates of Export (ANDREX)}, type = {Project Report}, publisher = {National Oceanography Centre}, year = {2011}, keywords = {ADCP, ANDREX, CO2, CFC, CTD, helium, James Cook, LADCP, nutrients, oxygen, oxygen isotope, radiocarbon, SF6, Southern Ocean, tritium, Weddell Sea}, url = {https://eprints.soton.ac.uk/208983/}, abstract = {This report describes scientific activities on RRS James Cook cruise 30, ?ANDREX?, westwards from 30?E and in the vicinity of latitude 60?S, between late December 2008 and late January 2009. The cruise was terminated about halfway through by a medical emergency. Hydrographic work comprised 27 CTD/LADCP stations. Water samples were captured for measurement of salinity, dissolved oxygen, inorganic nutrients, oxygen isotope fraction, chlorofluorocarbons and sulphur hexafluoride, dissolved inorganic carbon and alkalinity, helium / tritium / noble gases and radiocarbon. Underway measurements comprised navigation, currents (ADCP), meteorology, and sea surface temperature and salinity. The remainder of the hydrographic section was executed a year later on RRS James Clark Ross, cruise JR239.} } @article{soton49517, volume = {54}, number = {18-20}, title = {The island mass effect and biological carbon uptake for the subantarctic Crozet Archipelago}, author = {D.C.E. Bakker and M.C. Nielsdottir and P.J. Morris and H.J. Venables and A.J. Watson}, year = {2007}, pages = {2174--2190}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Carbon dioxide, Island mass effect, Iron supply, Crozet Archipelago, Subantarctic Front, Polar Frontal Zone, Antarctic Circumpolar Current, Southern Ocean rent, Southern Ocean}, url = {https://eprints.soton.ac.uk/49517/}, abstract = {Marine productivity is often higher downstream than upstream of islands. This so-called island mass effect was tested and quantified with respect to biological carbon uptake and air?sea exchange of carbon dioxide (CO2) at the Crozet Plateau between November 2004 and January 2005 during two CROZEX cruises. The remote plateau is situated at 45.5?47.0?S 49.0?53.0?E, south of the Subantarctic Front (SAF) in the Polar Frontal Zone (PFZ). Surface waters upstream (south) of the plateau had high nutrient and low chlorophyll (HNLC) concentrations. The fugacity of carbon dioxide (fCO2) in surface water was just below the atmospheric value and oceanic CO2 uptake was small (0.2{$\pm$}0.1 mol m?2) throughout CROZEX. The mixed-layer concentration of dissolved inorganic carbon (DIC) decreased by 15 ?mol kg?1 from November to January in these HNLC waters, indicating significant biological carbon uptake. Extensive phytoplankton blooms occurred downstream (north) of the plateau in austral spring. These reduced surface water fCO2 by 30?70 ?atm and DIC by 30?60 ?mol kg?1 and created an important oceanic sink for atmospheric CO2 of 0.6?0.8{$\pm$}0.4 mol m?2, corresponding to a total uptake of 1.3{$\pm$}0.8 Tg C (1 Tg=1012 g). The reduction of DIC in the upper 100 m was much larger downstream (2?3 mol m?2) than upstream (1 mol m?2) of the plateau in January, further confirming the existence of the island mass effect for the Crozet Archipelago. An additional finding is the sizeable DIC deficit in the HNLC waters upstream (south) of the plateau, suggesting that some HNLC waters of the PFZ are more productive than commonly thought. Deep mixed layers of 60?90 m may hide such sustained, modest marine productivity from detection by satellite. {\ensuremath{<}}br/{\ensuremath{>}}} } @article{soton352577, volume = {64}, title = {The residual circulation of the Southern Ocean: Which spatio-temporal scales are needed?}, author = {Maxime Ballarotta and Sybren Drijfhout and Till Kuhlbrodt and Kristofer D{\"o}{\"o}s}, year = {2013}, pages = {46--55}, journal = {Ocean Modelling}, keywords = {Overturning, Stream function, Southern Ocean, Bolus, Deacon Cell}, url = {https://eprints.soton.ac.uk/352577/}, abstract = {he Southern Ocean circulation consists of a complicated mixture of processes and phenomena that arise at different time and spatial scales which need to be parametrized in the state-of-the-art climate models. The temporal and spatial scales that give rise to the present-day residual mean circulation are here investigated by calculating the Meridional Overturning Circulation (MOC) in density coordinates from an eddy-permitting global model. The region sensitive to the temporal decomposition is located between 38?S and 63?S, associated with the eddy-induced transport. The ?Bolus? component of the residual circulation corresponds to the eddy-induced transport. It is dominated by timescales between 1 month and 1 year. The temporal behavior of the transient eddies is examined in splitting the ?Bolus? component into a ?Seasonal?, an ?Eddy? and an ?Inter-monthly? component, respectively representing the correlation between density and velocity fluctuations due to the average seasonal cycle, due to mesoscale eddies and due to large-scale motion on timescales longer than one month that is not due to the seasonal cycle. The ?Seasonal? bolus cell is important at all latitudes near the surface. The ?Eddy? bolus cell is dominant in the thermocline between 50?S and 35?S and over the whole ocean depth at the latitude of the Drake Passage. The ?Inter-monthly? bolus cell is important in all density classes and is maximal in the Brazil?Malvinas Confluence and the Agulhas Return Current. The spatial decomposition indicates that a large part of the Eulerian mean circulation is recovered for spatial scales larger than 11.25?, implying that small-scale meanders in the Antarctic Circumpolar Current (ACC), near the Subantarctic and Polar Fronts, and near the Subtropical Front are important in the compensation of the Eulerian mean flow.} } @article{soton385252, volume = {22}, number = {3}, month = {March}, author = {David K.A. Barnes and Louise Ireland and Oliver T. Hogg and Simon Morley and Peter Enderlein and Chester J. Sands}, title = {Why is the South Orkney Island shelf (the world's first high seas marine protected area) a carbon immobilization hotspot?}, journal = {Global Change Biology}, pages = {1110--1120}, year = {2016}, keywords = {benthos, carbon sink, climate change, feedback, phytoplankton, Southern Ocean}, url = {https://eprints.soton.ac.uk/385252/}, abstract = {The Southern Ocean archipelago, the South Orkney Islands (SOI), became the world's first entirely high seas marine protected area (MPA) in 2010. The SOI continental shelf ({\texttt{\char126}}44 000 km2), was less than half covered by grounded ice sheet during glaciations, is biologically rich and a key area of both sea surface warming and sea-ice losses. Little was known of the carbon cycle there, but recent work showed it was a very important site of carbon immobilization (net annual carbon accumulation) by benthos, one of the few demonstrable negative feedbacks to climate change. Carbon immobilization by SOI bryozoans was higher, per species, unit area and ice-free day, than anywhere-else polar. Here, we investigate why carbon immobilization has been so high at SOI, and whether this is due to high density, longevity or high annual production in six study species of bryozoans (benthic suspension feeders). We compared benthic carbon immobilization across major regions around West Antarctica with sea-ice and primary production, from remotely sensed and directly sampled sources. Lowest carbon immobilization was at the northernmost study regions (South Georgia) and southernmost Amundsen Sea. However, data standardized for age and density showed that only SOI was anomalous (high). High immobilization at SOI was due to very high annual production of bryozoans (rather than high densities or longevity), which were 2x, 3x and 5x higher than on the Bellingshausen, South Georgia and Amundsen shelves, respectively. We found that carbon immobilization correlated to the duration (but not peak or integrated biomass) of phytoplankton blooms, both in directly sampled, local scale data and across regions using remote-sensed data. The long bloom at SOI seems to drive considerable carbon immobilization, but sea-ice losses across West Antarctica mean that significant carbon sinks and negative feedbacks to climate change could also develop in the Bellingshausen and Amundsen seas.} } @article{soton469005, volume = {33}, number = {3}, month = {November}, author = {M. N. Bester and P. J.N. de Bruyn and W. C. Oosthuizen and C. A. Tosh and T. McIntyre and R. R. Reisinger and M. Postma and D. S. van der Merwe and M. Wege}, note = {Funding Information: Acknowledgements {--} Research at the PEIA was first funded by the Department of Transport, which also provided the logistics, and later by the Department of Environmental Affairs and Tourism, under the auspices of various research committees. Currently, funding is provided by the South African Department of Science and Technology, administered by the National Research Foundation, while the Department of Environmental Affairs provides the logistics. We are indebted to numerous personnel for their dedicated work on Marion Island when we were not in the field (see http://marion. sanap.org.za/index2.html), and to Azwianewi Makhado for setting the standard for students from the University of Venda that came after him. Richard Laws, Donald Siniff, John Bengtson and Ian Boyd, then members of the Scientific Committee for Antarctic Research Group of Specialists on Seals, provided their individual support in the 1990s when the long-term elephant seal mark-resighting progamme at the PEIA was under threat of being discontinued. Clarke Scholtz and Sue Nicolson as heads of department, and Johan du Toit and Elissa Cameron as directors of the MRI, were supportive throughout their tenures. Harry Burton, Joachim Pl{\"o}tz, Brent Stewart, John Arnould and Martin Haupt provided materially and spiritually, and Horst Bornemann, Alejandro Carlini?, Mark Hindell and Mirtha Lewis made meaningful collaboration possible. Graham Kerley, Ian Wilkinson, Greg Hofmeyr, Steve Kirkman, Pierre Pistorius (Marion Island expeditioners, students and friends all rolled into one), and Clive McMahon (Marion cat hunter, Macquarie sealer, student and friend), contributed enormously to the productivity of the MMP, each spending at least two seasons in the field and producing dissertations/theses and papers while at home base. We dedicate this paper to the memory of Alejandro Carlini, valued friend and colleague at IAA, who tragically passed away in the prime of his life in December 2010. Funding Information: Between April 1981 and March 1996, coordination of the overall research effort was facilitated by the appointment of a dedicated Antarctic Research Officer (ARO) within the South African National Antarctic Programme (SANAP). This position was located at the MRI, and although the ARO position was terminated in 1996, the officer (MNB) subsequently procured a permanent, full-time academic position within the Department of Zoology and Entomology at the University of Pretoria (UP) in April 1996. This ensured continuity in research. Seal research collaborations were forged especially with the then Branch: Marine and Coastal Management (now Oceans and Coasts of the Department of Environmental Affairs [DEA]), the University of Cape Town, the University of Venda, Port Elizabeth Museum at Bayworld, the Alfred Wegener Institute for Polar and Marine Research (Germany), Australian Antarctic Division, Hubbs-Sea World Research Institute (USA), Norwegian Polar Institute, Instituto Antartico Argentino (IAA), the Centro Nacional Patagonico (CENPAT) (Argentina), Deakin University (Australia) and the University of Tasmania (Australia). These collaborations continue to the present. The appointment of a UP graduate associated with the MMP (PJNdB) to a permanent, full-time academic position within the Department of Zoology and Entomology (January 2010), and alliances formed with other former MMP participants now employed at Oceans and Coasts, Nelson Mandela Metropolitan University (NMMU), Port Elizabeth Museum at Bayworld, and University of Venda, promise to be significant in the continuation and expansion of the MRI?s drive towards a strong and scientifically productive involvement in SANAP and other national Antarctic programmes through the study of marine mammals. However, this will be subject to continued procurement of funding from the Department of Science and Technology within SANAP. Copyright: Copyright 2012 Elsevier B.V., All rights reserved.}, title = {The Marine Mammal Programme at the Prince Edward Islands: 38 years of research}, year = {2011}, journal = {African Journal of Marine Science}, pages = {511--521}, keywords = {Antarctic fur seal, foraging ecology, killer whale, population dynamics, southern elephant seal, Subantarctic fur seal}, url = {https://eprints.soton.ac.uk/469005/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}The Marine Mammal Programme (MMP) conducts research on pinnipeds and killer whales Orcinus orca at Marion Island, Prince Edward Islands, under the auspices of the Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria. The history of the MMP, which has benefited from collaboration with leading national and international researchers, is described from its start through to current research. The setting up of long-term studies such as the mark-resighting of southern elephant seals Mirounga leonina commenced in 1983. The elephant seal population declined by 87\% between an initial census in 1951 and 2004. This was followed by a stabilisation period and a current increase. The recovery, and subsequent increase of sympatric populations of Subantarctic fur seals Arctocephalus tropicalis and Antarctic fur seals A. gazella (following cessation of commercial sealing), are documented. Insights into many aspects of elephant seal and fur seal biology, including life history, demography, diet, growth, foraging and ranging behaviour are described. Ancillary work on morphology, genetics, anthropogenic influences and rare events are mentioned, as well as the extent of current research that addresses population dynamics in an ecosystem context. Opportunistic photographic identification of killer whales and recent dedicated observations at Marion Island are used to determine population size, seasonal abundance and sociality of this population, and to further understanding of its potential impact on resident pinniped populations.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton354201, volume = {92}, month = {August}, title = {The reproductive ecology of deep-sea ophiuroids around the Crozet plateau, Southern Indian ocean, under contrasting productivity regimes}, author = {D.S.M. Billett and B.J. Bett and R. Evans and I. Cross and P.A. Tyler and G.A. Wolff}, year = {2013}, pages = {18--26}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Ophiuroid, Southern Indian Ocean, Crozet, Reproductive ecology, Ocean productivity, Benthos}, url = {https://eprints.soton.ac.uk/354201/}, abstract = {The reproductive characteristics of six ophiuroid species, Ophiura irrorata loveni, Ophiura lienosa, Amphioplus daleus, Ophiacantha cosmica, Ophiernus quadrispinus and Ophioplexa condita, were studied at two localities in the vicinity of the Crozet Islands in the Southern Indian Ocean. The two localities were notable in having almost identical environmental characteristics other than major differences in surface-water primary productivity and organic matter flux. The two localities were only 460 km apart. Three species were sufficiently abundant at the two sites to compare their reproductive biology under different productivity regimes. Ophiura irrorata loveni showed significant differences in oocyte size distributions and population size distributions between the two sites. The differences appeared to be related to the characteristics of organic matter flux at the two localities. Ophiacantha cosmica and Ophioplexa condita showed differences in abundance between the two sites. This appeared to be related to the availability of suitable substrata.} } @article{soton342694, volume = {461}, title = {Elephant seal foraging dives track prey distribution, not temperature: Comment on McIntyre et al. (2011)}, author = {P.H. Boersch-Supan and L. Boehme and J.F. Read and A.D. Rogers and A.S. Brierley}, year = {2012}, pages = {293--298}, journal = {Marine Ecology Progress Series}, keywords = {Climate change, Effect size, Prey field, Vertical structure, Southern elephant seal, Foraging ecology, Deep scattering layer}, url = {https://eprints.soton.ac.uk/342694/}, abstract = {McIntyre et al. (2011; Mar Ecol Prog Ser 441:257?272) concluded that climate change-related ocean warming may lead to deeper foraging dives by southern elephant seals as their prey is forced into deeper depths. They further assert that fitness for the seals will be reduced because of greater physiological costs for deep dives and the assumption that deep foraging is less successful. Their conclusions are based on an observed correlation between a temperature index and elephant seal diving depth but do not include any observations of prey. We recently observed pronounced differences in the vertical distribution of pelagic biota{--}biota that may well include elephant seal prey{--}across the same frontal zone considered by McIntyre et al. (2011) and believe that their suggested link between temperature and diving depth is actually a link between predators and distinct prey fields{--}a reflection of adaptive foraging behaviour in a complex and dynamic pelagic system. As such, the analysis of McIntyre et al. (2011) is uninformative about likely impacts of ocean warming.} } @article{soton335888, volume = {317-318}, month = {February}, title = {Foraminiferal Mg/Ca evidence for Southern Ocean cooling across the Eocene?Oligocene transition}, author = {Steven M. Bohaty and James C. Zachos and Margaret L. Delaney}, year = {2012}, pages = {251--261}, journal = {Earth and Planetary Science Letters}, keywords = {Foraminifera, Eocene, Oligocene, Southern Ocean, Stable oxygen isotopes, Mg/Ca, Ocean Drilling Program}, url = {https://eprints.soton.ac.uk/335888/}, abstract = {Constraining the magnitude of high-latitude temperature change across the Eocene?Oligocene transition (EOT) is essential for quantifying the magnitude of Antarctic ice-sheet expansion and understanding regional climate response to this event. To this end, we constructed high-resolution stable oxygen isotope (?18O) and magnesium/calcium (Mg/Ca) records from planktic and benthic foraminifera at four Ocean Drilling Program (ODP) sites in the Southern Ocean. Planktic foraminiferal Mg/Ca records from the Kerguelen Plateau (ODP Sites 738, 744, and 748) show a consistent pattern of temperature change, indicating 2?3 ?C cooling in direct conjunction with the first step of a two-step increase in benthic and planktic foraminiferal ?18O values across the EOT. In contrast, benthic Mg/Ca records from Maud Rise (ODP Site 689) and the Kerguelen Plateau (ODP Site 748) do not exhibit significant temperature change. The contrasting temperature histories derived from the planktic and benthic Mg/Ca records are not reconcilable, since vertical ?18O gradients remained nearly constant at all sites between 35.0 and 32.5 Ma. Based on the coherency of the planktic Mg/Ca records from the Kerguelen Plateau sites and complications with benthic Mg/Ca paleothermometry at low temperatures, the planktic Mg/Ca records are deemed the most reliable measure of Southern Ocean temperature change. We therefore interpret a uniform cooling of 2?3 ?C in both deep surface (thermocline) waters and intermediate deep waters of the Southern Ocean across the EOT. Cooling of Southern Ocean surface waters across the EOT was likely propagated to the deep ocean, since deep waters were primarily sourced on the Antarctic margin throughout this time interval. Removal of the temperature component from the observed foraminiferal ?18O shift indicates that seawater ?18O values increased by 0.6 {$\pm$} 0.15? across the EOT interval, corresponding to an increase in global ice volume to a level equivalent with 60?130\% modern East Antarctic ice sheet volume.} } @article{soton338393, volume = {62}, number = {1}, title = {Inter-annual variability and longer-term changes in the wave climate of Western Australia between 1970 and 2009}, author = {Cyprien Bosserelle and Charitha Pattiaratchi and Ivan Haigh}, year = {2012}, pages = {63--76}, journal = {Ocean Dynamics}, keywords = {Wave climate, Western Australia, Southern Indian Ocean}, url = {https://eprints.soton.ac.uk/338393/}, abstract = {Quantifying the long-term variability in wave conditions incident on a coastline is critical for predicting its resilience to future changes in the wave climate. In this study, a 40-year wave hindcast of the southern Indian Ocean has been created to assess the inter-annual variability and longer-term changes in the wave climate around Western Australia (WA) between 1970 and 2009. The model was validated against measurements from five wave buoys located along the WA coast. Changes in the mean annual significant wave height, 90th percentile wave height, peak period and mean wave direction were assessed, and the tracks of all wave events generating wave heights above 7 m were digitised and analysed for significant changes. Results show strong annual and inter-annual variability in the mean significant wave height, the 90th percentile wave height and the number of large events (wave height?\>?7 m) that impact the WA coastline. A significant positive trend in annual mean wave height was found in the southwest region of WA over the 40-year simulation. This appears to be due to an increase in intensity of the storm belt in the Southern Ocean which is associated with an increasing positive polarity in the Southern Annular Mode. However, no significant trends were found in the 90th percentile wave height or the number of large wave events impacting Western Australia. Although the number of large wave events in the southern Indian Ocean have increased, their potential to impact the coastal regions of Western Australia are reduced due to storm tracks being located further south, therefore balancing the number of large wave events reaching the WA coast.} } @article{soton6141, volume = {49}, number = {3}, title = {The tracer signature of Antarctic bottom water and its spread in the Southwest Indian Ocean: Part I - CFC-derived translation rate and topographic control around the Southwest Indian Ridge and the Conrad Rise}, author = {S.M. Boswell and D. Smythe-Wright}, year = {2002}, pages = {555--573}, journal = {Deep Sea Research Part I: Oceanographic Research Papers}, keywords = {WOCE, COUNTRYGB, TRACERS, DEEP WATER MASSES, ANTARCTIC BOTTOM WATER, SOUTHERN OCEAN}, url = {https://eprints.soton.ac.uk/6141/} } @article{soton6142, volume = {49}, number = {3}, title = {The tracer signature of Antarctic bottom water and its spread in the Southwest Indian Ocean: Part II - Dissolution fluxes of dissolved silicate and their impact on its use as a chemical tracer}, author = {S.M. Boswell and D. Smythe-Wright and S.E. Holley and D. Kirkwood}, year = {2002}, pages = {575--590}, journal = {Deep Sea Research Part I: Oceanographic Research Papers}, keywords = {WOCE, COUNTRYGB, TRACERS, SILICON CYCLE, BIOGEOCHEMISTRY, SOUTHERN OCEAN, ANTARCTIC OCEAN}, url = {https://eprints.soton.ac.uk/6142/} } @article{soton49372, volume = {54}, number = {16-17}, title = {Introduction to ANDEEP, summary and outlook}, author = {A. Brandt and B. Ebbe and A.J. Gooday}, year = {2007}, pages = {1645--1651}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Southern Ocean, Deep sea, Biodiversity, Meiofauna, Makrofauna, Megafauna}, url = {https://eprints.soton.ac.uk/49372/}, abstract = {The multidisciplinary international project ANDEEP (Antarctic deep-sea benthic biodiversity: colonisation history and recent community patterns) involved a two-leg expedition to the Weddelland Scotia seas in 2002 and a third expedition in 2005 to the Cape and Agulhas basins, Weddell Sea, Bellingshausen Sea and Drake Passage (Fig. 1). In 2004, we published the first results, based on the material collected during ANDEEP I/II (Brandt and Hilbig, 2004). This second volume concerns work done since 2004, including results based on material obtained during ANDEEP III. These three expeditions yielded a very rich and unique collection of material and data. Much work remains to be done and publications will continue to appear in the literature for many years to come. However, the end of the directly funded phase of the project provides a good opportunity to revisit the original questions that we had hoped to answer, to determine our success in doing so, and to define remaining gaps in our knowledge of the deep Southern Ocean faunas. Generally, the goals that were set for ANDEEP have been reached. In particular, there has been an increase in our knowledge of the scale and patterns of species diversity in the deep ocean and an improved understanding of the origins of the abyssal fauna of the Southern Ocean. Many of the remaining gaps have emerged from the knowledge we gained and thus are part of the success of the project rather than an indication of failure.} } @article{soton356885, volume = {43}, number = {8}, month = {August}, author = {Liam Brannigan and Yueng-Djern Lenn and Tom P. Rippeth and Elaine McDonagh and Teresa K. Chereskin and Janet Sprintall}, title = {Shear at the Base of the Oceanic Mixed Layer Generated by Wind Shear Alignment}, journal = {Journal of Physical Oceanography}, pages = {1798--1810}, year = {2013}, keywords = {Southern Ocean, Atmosphere-ocean interaction, Diapycnal mixing, Shear structure/flows, Oceanic mixed layer, Kelvin-Helmholtz instabilities}, url = {https://eprints.soton.ac.uk/356885/}, abstract = {Observations are used to evaluate a simple theoretical model for the generation of near-inertial shear spikes at the base of the open ocean mixed layer when the upper ocean displays a two-layer structure. The model predicts that large changes in shear squared can be produced by the alignment of the wind and shear vectors. A climatology of stratification and shear variance in Drake Passage is presented, which shows that these assumptions are most applicable to summer, fall, and spring but are not highly applicable to winter. Temperature, salinity, and velocity data from a high spatial resolution cruise in Drake Passage show that the model does not predict all large changes in shear variance; the model is most effective at predicting changes in shear squared when it arises owing to near-inertial wind-driven currents without requiring a rotating resonant wind stress. The model is also more effective where there is a uniform mixed layer above a strongly stratified transition layer. Rotary spectral and statistical analysis of an additional 242 Drake Passage transects from 1999 to 2011 confirmed the presence of this shear-spiking mechanism, particularly in summer, spring, and fall when stratification is stronger.} } @article{soton354488, volume = {41}, number = {1}, month = {January}, author = {J. Alexander Brearley and Katy L. Sheen and Alberto C. Naveira Garabato and David A. Smeed and Kevin G. Speer and Andeaus M. Thurnherr and Michael M. Meredith and Stephanie N. Waterman}, title = {Deep boundary current disintegration in Drake Passage}, journal = {Geophysical Research Letters}, pages = {121--127}, year = {2014}, keywords = {Boundary currents, Eddies, Overturning, Southern Ocean}, url = {https://eprints.soton.ac.uk/354488/}, abstract = {The fate of a deep boundary current that originates in the Southeast Pacific and flows southward along the continental slope of South America is elucidated. The current transports poorly ventilated water of low salinity (a type of Pacific Deep Water; PDW), into Drake Passage. East of Drake Passage, the boundary current breaks into fresh anticyclonic eddies, nine examples of which were observed in mooring data from December 2009 to March 2012. The observed eddies appear to originate mainly from a topographic separation point close to 60?W, have typical diameters of 20?60?km and accompanying Rossby numbers of 0.1?0.3. These features are likely to be responsible for transporting PDW meridionally across the ACC, explaining the near-homogenization of Circumpolar Deep Water properties downstream of Drake Passage. This mechanism of boundary current breakdown may constitute an important process in the Southern Ocean overturning circulation.} } @article{soton374633, volume = {29}, number = {3}, month = {March}, author = {Peter J. Brown and Lo{\"i}c Jullion and Peter Landsch{\"u}tzer and Dorothee C.E. Bakker and Alberto C. Naveira Garabato and Michael P. Meredith and Sinhu{\'e} Torres-Vald{\'e}s and Andrew Watson and Mario Hoppema and Brice Loose and Elizabeth M. Jones and Maciej Telszewski and Steve D. Jones and Rik Wanninkhof}, title = {Carbon dynamics of the Weddell Gyre, Southern Ocean}, journal = {Global Biogeochemical Cycles}, pages = {288--306}, year = {2015}, keywords = {Southern Ocean, Weddell Gyre, ocean carbon cycle, neural network, air-sea exchange of CO2, observations}, url = {https://eprints.soton.ac.uk/374633/}, abstract = {The accumulation of carbon within the Weddell Gyre, and its exchanges across the gyre boundaries are investigated with three recent full-depth oceanographic sections enclosing this climatically-important region. The combination of carbon measurements with ocean circulation transport estimates from a box inverse analysis reveal that deep water transports associated with Warm Deep Water (WDW) and Weddell Sea Deep Water dominate the gyre's carbon budget, while a dual-cell vertical overturning circulation leads to both upwelling and the delivery of large quantities of carbon to the deep ocean. Historical sea surface pCO2 observations, interpolated using a neural network technique, confirm the net summertime sink of 0.044 to 0.058 {$\pm$} 0.010 Pg C yr-1 derived from the inversion. However, a wintertime outgassing signal similar in size results in a statistically insignificant annual air-to-sea CO2 flux of 0.002 {$\pm$} 0.007 Pg C yr-1 (mean 1998-2011) to 0.012 {$\pm$} 0.024 Pg C yr-1 (mean 2008-2010) to be diagnosed for the Weddell Gyre. A surface layer carbon balance, independently derived from in situ biogeochemical measurements reveals that freshwater inputs and biological drawdown decrease surface ocean inorganic carbon levels more than they are increased by WDW entrainment, resulting in an estimated annual carbon sink of 0.033 {$\pm$} 0.021 Pg C yr-1. Although relatively less efficient for carbon uptake than the global oceans, the summertime Weddell Gyre suppresses the winter outgassing signal, while its biological pump and deep water formation act as key conduits for transporting natural and anthropogenic carbon to the deep ocean where they can reside for long timescales.} } @article{soton364341, volume = {41}, number = {8}, month = {April}, author = {T.J. Browning and H.A. Bouman and G.M. Henderson and T.A. Mather and D.M. Pyle and C. Schlosser and E.M.S. Woodward and C.M. Moore}, title = {Strong responses of Southern Ocean phytoplankton communities to volcanic ash}, journal = {Geophysical Research Letters}, pages = {2851--2857}, year = {2014}, keywords = {iron fertilization, volcanic ash, Southern Ocean, colimitation, manganese, phytoplankton}, url = {https://eprints.soton.ac.uk/364341/}, abstract = {Volcanic eruptions have been hypothesized as an iron supply mechanism for phytoplankton blooms; however, little direct evidence of stimulatory responses has been obtained in the field. Here we present the results of twenty-one 1?2?day bottle enrichment experiments from cruises in the South Atlantic and Southern Ocean which conclusively demonstrated a photophysiological and biomass stimulation of phytoplankton communities following supply of basaltic or rhyolitic volcanic ash. Furthermore, experiments in the Southern Ocean demonstrated significant phytoplankton community responses to volcanic ash supply in the absence of responses to addition of dissolved iron alone. At these sites, dissolved manganese concentrations were among the lowest ever measured in seawater, and we therefore suggest that the enhanced response to ash may have been a result of the relief of manganese (co)limitation. Our results imply that volcanic ash deposition events could trigger extensive phytoplankton blooms, potentially capable of significant impacts on regional carbon cycling.} } @article{soton1293, volume = {24}, number = {2}, title = {Lagrangian and satellite observations of the Brazilian Coastal Current}, author = {R. Buss de Souza and I.S. Robinson}, year = {2004}, pages = {241--262}, journal = {Continental Shelf Research}, keywords = {south-western atlantic, southern brazilian shelf, surface currents, drifting buoys, avhrr, coroas, woce}, url = {https://eprints.soton.ac.uk/1293/}, abstract = {The waters dominating the Brazilian Continental Shelf to the south of Santa Marta Cape (28[deg]40'S) are marked by their strong interannual variability. Both the seasonal oscillation of the Brazil-Malvinas (Falkland) Confluence (BMC) region and the seasonal variations of the La Plata River and Patos Lagoon outflows are reflected in the seasonal changes of the vertical and horizontal water mass structure in the Southern Brazilian Shelf. In the region to the north of Santa Marta Cape, the shelf is mainly described in the literature as dominated by Tropical Waters (TW) transported southwards by the Brazil Current (BC). However, the first Lagrangian (buoy) measurements made on the inner Brazilian shelf have shown that a coastal current flowing in the opposite direction in relation to the BC occurred on the shelf as far north as 24[deg]S during the 1993 austral autumn and winter. Recent papers have suggested that the arrival at low latitudes of cold waters originating in the BMC region is an anomalous phenomenon and that it can be either forced by local winds during wintertime or related to the ENSO. High-resolution sea surface temperature (SST) imagery and the Lagrangian measurements taken in 1993 and 1994 are used in this paper to describe the temperatures, velocity, energy and oscillations present in this coastal current. These two data sets show that the current is not only fed by waters of Subantarctic or coastal origin but also receives a contribution of TW at the surface by lateral mixing. By analysing a set of monthly averaged SST images from 1982 to 1995, this work suggests that the intrusion of cold waters transported by the coastal current can be a regular winter phenomenon occurring on the Brazilian shelf at latitudes up to the vicinity of 25[deg]S. Given its consistency, this current is named here the Brazilian Coastal Current.} } @article{soton455503, volume = {8}, number = {1}, month = {June}, title = {A critical assessment of marine predator isoscapes within the southern Indian Ocean}, author = {Tegan Carpenter-Kling and Pierre Pistorius and Ryan Reisinger and Yves Cherel and Ma{\"e}lle Connan}, year = {2020}, journal = {Movement Ecology}, keywords = {Geolocation, Penguins, Procellariiformes, Seabirds, Southern Ocean, Stable isotope ecology}, url = {https://eprints.soton.ac.uk/455503/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Background: Precise and accurate retrospective geolocation of marine predators via their tissues' isotopic composition relies on quality reference maps of relevant isotopic gradients ("isoscapes"). Additionally, a good working knowledge of any discrimination factors that may offset a marine predator's isotopic composition from baseline isotopic values, as well as tissue specific retention rates, are imperative. We provide a critical assessment of inter-specific differences among marine predator-level isoscapes within the Indian Sector of the Southern Ocean. Methods: We combined fine-scale GPS tracking data and concurrent blood plasma {\ensuremath{\delta}}13C and {\ensuremath{\delta}}15N values of eight seabird species (three albatross, two giant petrel and three penguin species) breeding at Marion Island to produce species- and guild-specific isoscapes. Results: Overall, our study revealed latitudinal spatial gradients in both {\ensuremath{\delta}}13C and {\ensuremath{\delta}}15N for far-ranging seabirds (albatrosses and giant petrels) as well as inshore-offshore gradients for near-ranging seabirds (penguins). However, at the species level, latitudinal spatial gradients were not reflected in the {\ensuremath{\delta}}13C and {\ensuremath{\delta}}15N isoscapes of two and three, respectively, of the five far-ranging species studied. It is therefore important when possible to estimate and apply species-specific isoscapes or have a good understanding of any factors and pathways affecting marine predators' isotopic composition when estimating the foraging distribution of marine predators via their tissues' stable isotope compositions. Conclusions: Using a multi-species approach, we provide evidence of large and regional scale systematic spatial variability of {\ensuremath{\delta}}13C and {\ensuremath{\delta}}15N at the base of the marine food web that propagates through trophic levels and is reflected in the isotopic composition of top predators' tissues.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton455502, volume = {10}, number = {20}, month = {October}, author = {Tegan Carpenter-Kling and Ryan R. Reisinger and Florian Orgeret and Ma{\"e}lle Connan and Kim L. Stevens and Peter G. Ryan and Azwianewi Makhado and Pierre A. Pistorius}, note = {Funding Information: We thank all field personnel who spent many long hours assisting with the deployment of GPS dataloggers. A special mention goes to Stefan Schoombie, Janine Schoombie, Jessie Berndt, Albert Snyman, Makhudu Masotla and David Green without whose dedication and excellent fieldwork this study would not have been possible. Research on Marion Island is made possible through the logistical support from South Africa's Department of Environment, Forestry, and Fisheries. Financial support was received from the South Africa's National Research Foundation (NRF), through its South African National Antarctic Programme, as a grant to Pierre Pistorius (grant number SNA093071) and Ryan Reisinger was the recipient of a NRF postdoctoral grant (SANCOR grant 94916). We thank the associate editor and reviewers for their comments. Funding Information: We thank all field personnel who spent many long hours assisting with the deployment of GPS dataloggers. A special mention goes to Stefan Schoombie, Janine Schoombie, Jessie Berndt, Albert Snyman, Makhudu Masotla and David Green without whose dedication and excellent fieldwork this study would not have been possible. Research on Marion Island is made possible through the logistical support from South Africa's Department of Environment, Forestry, and Fisheries. Financial support was received from the South Africa's National Research Foundation (NRF), through its South African National Antarctic Programme, as a grant to Pierre Pistorius (grant number SNA093071) and Ryan Reisinger was the recipient of a NRF postdoctoral grant (SANCOR grant 94916). We thank the associate editor and reviewers for their comments. Publisher Copyright: {\copyright} 2020 The Authors. Ecology and Evolution published by John Wiley \& Sons Ltd. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.}, title = {Foraging in a dynamic environment: Response of four sympatric sub-Antarctic albatross species to interannual environmental variability}, year = {2020}, journal = {Ecology and Evolution}, pages = {11277--11295}, keywords = {behavioral plasticity, biologging, central place foragers, marine predators, resilience, Southern Annual Mode}, url = {https://eprints.soton.ac.uk/455502/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Seasonal and annual climate variations are linked to fluctuations in the abundance and distribution of resources, posing a significant challenge to animals that need to adjust their foraging behavior accordingly. Particularly during adverse conditions, and while energetically constrained when breeding, animals ideally need to be flexible in their foraging behavior. Such behavioral plasticity may separate ?winners? from ?losers? in light of rapid environmental changes due to climate change. Here, the foraging behavior of four sub-Antarctic albatross species was investigated from 2015/16 to 2017/18, a period characterized by pronounced environmental variability. Over three breeding seasons on Marion Island, Prince Edward Archipelago, incubating wandering (WA, Diomedea exulans; n = 45), grey-headed (GHA, Thalassarche chrysostoma; n = 26), sooty (SA, Phoebetria fusca; n = 23), and light-mantled (LMSA, P. palpebrata; n = 22) albatrosses were tracked with GPS loggers. The response of birds to environmental variability was investigated by quantifying interannual changes in their foraging behavior along two axes: spatial distribution, using kernel density analysis, and foraging habitat preference, using generalized additive mixed models and Bayesian mixed models. All four species were shown to respond behaviorally to environmental variability, but with substantial differences in their foraging strategies. WA was most general in its habitat use defined by sea surface height, eddy kinetic energy, wind speed, ocean floor slope, and sea-level anomaly, with individuals foraging in a range of habitats. In contrast, the three smaller albatrosses exploited two main foraging habitats, with habitat use varying between years. Generalist habitat use by WA and interannually variable use of habitats by GHA, SA, and LMSA would likely offer these species some resilience to predicted changes in climate such as warming seas and strengthening of westerly winds. However, future investigations need to consider other life-history stages coupled with demographic studies, to better understand the link between behavioral plasticity and population responses.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton360798, volume = {118}, number = {10}, month = {October}, author = {Maxi Castrillejo and Peter J. Statham and Gary R. Fones and H{\'e}l{\`e}ne Planquette and Farah Idrus and Keiron Roberts}, title = {Dissolved trace metals (Ni, Zn, Co, Cd, Pb, Al, and Mn) around the Crozet Islands, Southern Ocean}, journal = {Journal of Geophysical Research: Oceans}, pages = {5188--5201}, year = {2013}, keywords = {Southern Ocean, trace metals, biogeochemical cycles, iron fertilization}, url = {https://eprints.soton.ac.uk/360798/}, abstract = {A phytoplankton bloom shown to be naturally iron (Fe) induced occurs north of the Crozet Islands (Southern Ocean) every year, providing an ideal opportunity to study dissolved trace metal distributions within an island system located in a high nutrient low chlorophyll (HNLC) region. We present water column profiles of dissolved nickel (Ni), zinc (Zn), cobalt (Co), cadmium (Cd), lead (Pb), aluminium (Al), and manganese (Mn) obtained as part of the NERC CROZEX program during austral summer (2004?2005). Two stations (M3 and M1) were sampled downstream (north) of Crozet in the bloom area and near the islands, along with a control station (M2) in the HNLC zone upstream (south) of the islands. The general range found was for Ni, 4.64?6.31 nM; Zn, 1.59?7.75 nM; Co, 24?49 pM; Cd, 135?673 pM; Pb, 6?22 pM; Al, 0.13?2.15 nM; and Mn, 0.07?0.64 nM. Vertical profiles indicate little island influence to the south with values in the range of other trace metal deprived regions of the Southern Ocean. Significant removal of Ni and Cd was observed in the bloom and Zn was moderately correlated with reactive silicate (Si) indicating diatom control over the internal cycling of this metal. Higher concentrations of Zn and Cd were observed near the islands. Pb, Al, and Mn distributions also suggest small but significant atmospheric dust supply particularly in the northern region.} } @techreport{soton19316, editor = {H. Cattle and M. Sparrow}, month = {October}, type = {Project Report}, title = {CLIVAR Exchanges No. 35. Southern Hemisphere Climate Variability}, publisher = {International CLIVAR Project Office}, year = {2005}, series = {No. 35 (Vol. 10(4))}, keywords = {CLIVAR, WCRP, Exchanges, newsletter, Southern Hemisphere Climate Variability}, url = {https://eprints.soton.ac.uk/19316/} } @article{soton453162, volume = {170}, month = {January}, title = {How does the Southern Ocean palaeoenvironment during Marine Isotope Stage 5e compare to the modern?}, author = {M. Chadwick and C.s. Allen and L.c. Sime and X. Crosta and C.-d. Hillenbrand}, year = {2022}, note = {This work was supported by the Natural Environmental Research Council [grant number NE/L002531/1] and contributes to British Antarctic Survey's ?Polar Science for Planet Earth? program.}, journal = {Marine Micropaleontology}, keywords = {Diatom, MIS 5e, Marine Sediment Core, Palaeoenvironment, Southern Ocean}, url = {https://eprints.soton.ac.uk/453162/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Marine Isotope Stage (MIS) 5e (130?116 ka) represents an important ?process analogue? for understanding the climatic feedbacks and responses likely active under future anthropogenic warming. Reconstructing the Southern Ocean (SO) palaeoenvironment during MIS 5e and comparing it to the present day provides insights into the different responses of the SO sectors to a warmer climate. This study presents new records from seven marine sediment cores for MIS 5e together with their surface sediment records; all cores are located south of 55 {\ensuremath{<}}sup{\ensuremath{>}}o{\ensuremath{<}}/sup{\ensuremath{>}}S. We investigate changes in diatom species assemblage and the accompanying variations in sea surface temperatures, winter sea-ice extent (WSIE) and glacial meltwater flux. All records show warmer conditions and a reduced WSIE during MIS 5e relative to the surface sediments. While the Pacific and Indian Sector records present very stable conditions throughout MIS 5e, the Atlantic Sector records display much more changeable conditions, particularly with respect to the WSIE. These variable conditions are attributed to higher iceberg and glacial meltwater flux in the Weddell Sea. This evidence for increased iceberg and glacial meltwater flux in the Weddell Sea during MIS 5e may have significant implications for understanding the stability of the West Antarctic Ice Sheet, both during MIS 5e and under future warming. {\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton440895, volume = {229}, month = {February}, title = {Analysing the timing of peak warming and minimum winter sea-ice extent in the Southern Ocean during MIS 5e}, author = {M. Chadwick and C.s. Allen and L.c. Sime and C.-d. Hillenbrand}, year = {2020}, journal = {Quaternary Science Reviews}, keywords = {Interglacial, Palaeoceanography, Sediment cores, Southern Ocean}, url = {https://eprints.soton.ac.uk/440895/}, abstract = {The peak of the Last Interglacial, Marine Isotope Stage (MIS) 5e (130?116 ka), provides a valuable ?process analogue? for validating the climatic feedbacks and forcings likely active under future anthropogenic warming. Reconstructing exact timings of MIS 5e peak warming and minimum winter sea-ice extent (WSIE) throughout the Southern Ocean (SO) will help to identify the interactions and feedbacks within the ice-ocean system. Here we present a new MIS 5e marine sediment record from the SW Atlantic sector together with 28 published core records (chronologies standardised to the LR04 {\ensuremath{\delta}}18O benthic stack; Lisiecki and Raymo, 2005) to investigate the timing and sequence of minimum WSIE and peak warming across the SO. Sea-surface temperatures (SSTs) peaked earliest in the Indian (20oE?150oE) and Atlantic (70oW?20oE) sectors, at 128.7 {$\pm$} 0.8 ka and 127.4 {$\pm$} 1.1 ka respectively, followed by the Pacific sector (150oE?70oW) at 124.9 {$\pm$} 3.6 ka. The interval of minimum WSIE for all three sectors occurred within the period from 129?125 ka, consistent with the {$\sim$}128 ka sea salt flux minimum in Antarctic ice cores. Minimum WSIE appears to have coincided with peak July insolation at 55 oS, suggesting it could be linked with the mildest winters. The reduced WSIE during MIS 5e would have likely reduced the production of deep- and bottom water masses, inhibiting storage of CO2 in the abyssal ocean and lowering nutrient availability in SO surface waters. Examining a wide spatial range of proxy records for MIS 5e is a critical step forward in understanding climatic interactions and processes that will be active under warmer global temperatures.} } @article{soton42479, volume = {54}, number = {18-20}, title = {Radium isotopes as tracers of iron sources fueling a Southern Ocean phytoplankton bloom}, author = {M.A. Charette and M.E. Gonneea and P.J. Morris and P. Statham and G. Fones and H. Planquette and I. Salter and A.C. Naveira Garabato}, year = {2007}, pages = {1989--1998}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Radium isotopes, Iron, Productivity, Ocean mixing, Southern Ocean}, url = {https://eprints.soton.ac.uk/42479/}, abstract = {Elevated levels of productivity in the wake of Southern Ocean island systems are common despite the fact that they are encircled by high-nutrient low-chlorophyll (HNLC) waters. In the Crozet Plateau region, it has been hypothesized that iron from island runoff or sediments of the plateau could be fueling the austral summer phytoplankton bloom. Here, we use radium isotopes to quantify the rates of surface-ocean iron supply fueling the bloom in the Crozet Plateau region. A 1-D eddy-diffusion-mixing model applied to a 228Ra profile (t1/2=5.75 years) at a station north of the islands suggests fast vertical mixing in the upper 300 m (Kz=11?100 cm2 s?1) with slower mixing between 300 and 1000 m (Kz=1.5 cm2 s?1). This estimate is discussed in the context of Kz derived from the CTD/LADCP data. In combination with the dissolved Fe profile at this location, we estimated a vertical flux of between 5.6 and 31 nmol Fe m?2 d?1. The cross-plateau gradients in the short-lived radium isotopes, 224Ra (t1/2=3.66 d) and 223Ra (t1/2=11.4 d), yielded horizontal eddy diffusivities (Kh) of 39 and 6.6 m2 s?1, respectively. If we assume that the islands (surface runoff) alone were supplying dissolved Fe to the bloom region, then the flux estimates range from 2.3 to 14 nmol Fe m?2 d?1. If the plateau sediments are considered a source of Fe, and conveyed to the bloom region through deep winter mixing combined with horizontal transport, then this flux may be as high as 64?390 nmol Fe m?2 d?1. Combined, these Fe sources are sufficient to initiate and maintain the annual phytoplankton bloom.} } @article{soton384870, volume = {175}, number = {2}, month = {October}, author = {Chong Chen and Katrin Linse and Christopher N. Roterman and Jonathan T. Copley and Alex D. Rogers}, title = {A new genus of large hydrothermal vent-endemic gastropod (Neomphalina: Peltospiridae)}, journal = {Zoological Journal of the Linnean Society}, pages = {319--335}, year = {2015}, keywords = {East Scotia Ridge, Gigantopelta, Indian Ocean, population genetics, Southern Ocean}, url = {https://eprints.soton.ac.uk/384870/}, abstract = {Recently discovered hydrothermal vent fields on the East Scotia Ridge (ESR, 56?60?S, 30?W), Southern Ocean, and the South West Indian Ridge (SWIR, 37?S 49?E), Indian Ocean, host two closely related new species of peltospirid gastropods. Morphological and molecular (mitochondrial cytochrome c oxidase subunit I, COI) characterization justify the erection of Gigantopelta gen. nov. within the Peltospiroidae with two new species, Gigantopelta chessoia sp. nov. from ESR and Gigantopelta aegis sp. nov. from SWIR. They attain an extremely large size for the clade Neomphalina, reaching 45.7?mm in shell diameter. The oesophageal gland of both species is markedly enlarged. Gigantopelta aegis has a thick sulphide coating on both the shell and the operculum of unknown function. The analysis of a 579-bp fragment of the COI gene resulted in 19?28\% pairwise distance between Gigantopelta and six other genera in Peltospiridae, whereas the range amongst those six genera was 12?28\%. The COI divergence between the two newly described species of Gigantopelta was 4.43\%. Population genetics analyses using COI (370?bp) of 30 individuals of each species confirmed their genetic isolation and indicate recent rapid demographic expansion in both species. {\ensuremath{<}}br/{\ensuremath{>}}{\ensuremath{<}}br/{\ensuremath{>}}} } @article{soton348334, month = {November}, title = {Meridional overturning circulation: stability and ocean feedbacks in a box model}, author = {Andrea A. Cimatoribus and Sybren S. Drijfhout and Henk A. Dijkstra}, year = {2012}, journal = {Climate Dynamics}, keywords = {atlantic, meridional overturning circulation, stability, freshwater, salt-advection feedback, southern subtropical gyre}, url = {https://eprints.soton.ac.uk/348334/}, abstract = {A box model of the inter-hemispheric Atlantic meridional overturning circulation is developed, including a variable pycnocline depth for the tropical and subtropical regions. The circulation is forced by winds over a periodic channel in the south and by freshwater forcing at the surface. The model is aimed at investigating the ocean feedbacks related to perturbations in freshwater forcing from the atmosphere, and to changes in freshwater transport in the ocean. These feedbacks are closely connected with the stability properties of the meridional overturning circulation, in particular in response to freshwater perturbations. A separate box is used for representing the region north of the Antarctic circumpolar current in the Atlantic sector. The density difference between this region and the north of the basin is then used for scaling the downwelling in the north. These choices are essential for reproducing the sensitivity of the meridional overturning circulation observed in general circulation models, and therefore suggest that the southernmost part of the Atlantic Ocean north of the Drake Passage is of fundamental importance for the stability of the meridional overturning circulation. With this configuration, the magnitude of the freshwater transport by the southern subtropical gyre strongly affects the response of the meridional overturning circulation to external forcing. The role of the freshwater transport by the overturning circulation (M ov ) as a stability indicator is discussed. It is investigated under which conditions its sign at the latitude of the southern tip of Africa can provide information on the existence of a second, permanently shut down, state of the overturning circulation in the box model. M ov will be an adequate indicator of the existence of multiple equilibria only if salt-advection feedback dominates over other processes in determining the response of the circulation to freshwater anomalies. M ov is a perfect indicator if feedbacks other than salt-advection are negligible.} } @article{soton50575, volume = {5}, number = {1}, month = {February}, author = {J.B. Colwell and M.F. Coffin and C.J. Pigram and H.L. Davies and H.M.J. Stagg and P.J. Hill}, title = {Seismic stratigraphy and evolution of the Raggatt Basin, southern Kerguelen Plateau}, journal = {Marine and Petroleum Geology}, pages = {75--81}, year = {1988}, keywords = {Southern Indian Ocean, Kerguelen Plateau, Raggatt Basin, Cretaceous, seismic stratigraphy, tectonic evolution, ocean currents}, url = {https://eprints.soton.ac.uk/50575/}, abstract = {Six major seismic stratigraphic sequences in the Raggatt Basin on the southern Kerguelen Plateau overlie a basement complex of Cretaceous or greater age. The complex includes dipping reflectors which were apparently folded and eroded before the Raggatt Basin developed. The seismic stratigraphic sequences include a basal unit F, which fills depressions in basement; a thick unit, E, which has a mounded upper surface (volcanic or carbonate mounds); a depression-filling unit, D; a thick unit C which is partly Middle to Late Eocene; and two post-Eocene units, A and B, which are relatively thin and more limited in areal extent than the underlying sequences. A mid or Late Cretaceous erosional episode was followed by subsidence and basin development, interrupted by major erosion in the mid Tertiary. Late Cenozoic sedimentation was affected by vigorous ocean currents.} } @article{soton8793, volume = {166}, number = {2234}, month = {April}, author = {J. Copley}, title = {In from the cold}, journal = {New Scientist}, pages = {30--35}, year = {2000}, keywords = {UKRAINE, PIONTKOVSKY, S, INSTITUTE OF BIOLOGY OF SOUTHERN SEAS, SBU}, url = {https://eprints.soton.ac.uk/8793/}, abstract = {With the Cold War over, Sergey Piontkovsky thought nothing of picking up the phone or sending e-mails to Western colleagues from his office in Sevastopol, Ukraine. Just a routine job for a marine biologist working on projects with scientists overseas. But Ukraine?s security service had other ideas. This latter-day KGB decided Piontkovsky?s chats amounted to the leaking of state secrets. Raids were ordered on his home and offices at the Institute of Biology of the Southern Seas. He was interrogated and banned from leaving the country. Thanks to a massive campaign involving scientists around the world, charges were never?} } @article{soton355047, volume = {40}, number = {11}, month = {June}, author = {Matthew P. Couldrey and Lo{\"i}c Jullion and Alberto C. Naveira Garabato and Craig Rye and Laura Herraiz-Borreguero and Peter J. Brown and Michael P. Meredith and Kevin L. Speer}, title = {Remotely induced warming of Antarctic Bottom Water in the eastern Weddell gyre}, journal = {Geophysical Research Letters}, pages = {2755--2760}, year = {2013}, keywords = {AABW, ACC, Southern Ocean, Cape Darnley}, url = {https://eprints.soton.ac.uk/355047/}, abstract = {Four repeat hydrographic sections across the eastern Weddell gyre at 30?E reveal a warming (by {\texttt{\char126}}0.1?C) and lightening (by {\texttt{\char126}}0.02?0.03 kg m?3) of the Antarctic Bottom Water (AABW) entering the gyre from the Indian sector of the Southern Ocean between the mid-1990s and late 2000s. Historical hydrographic and altimetric measurements in the region suggest that the most likely explanation for the change is increased entrainment of warmer mid-depth Circumpolar Deep Water by cascading shelf water plumes close to Cape Darnley, where the Indian-sourced AABW entering the Weddell gyre from the east is ventilated. This change in entrainment is associated with a concurrent southward shift of the Antarctic Circumpolar Current's (ACC) southern boundary in the region. This mechanism of AABW warming may affect wherever the ACC flows close to Antarctica.} } @techreport{soton252, type = {Project Report}, title = {RRS James Clark Ross Cruise JR55, 21 Nov-14 Dec 2000. Drake Passage repeat hydrography: WOCE Southern Section 1b ? Burdwood Bank to Elephant Island}, author = {S.A. Cunningham}, publisher = {Southampton Oceanography Centre, University of Southampton}, year = {2001}, series = {35}, keywords = {Antarctic Circumpolar Current, Antarctic Ocean, Acoustic Doppler Current Profiler, CTD observations, Drake Passage, James Clark Ross, cruise 55 2000, lowered ADCP, Southern Ocean, vessel mounted ADCP, WOCE, World Ocean Circulation Experiment, XBT}, url = {https://eprints.soton.ac.uk/252/}, abstract = {This report describes the sixth repeat hydrography section across Drake Passage, first established during the International World Ocean Circulation Experiment. Through continuation of this time series the nature of the interannual variability in the location and properties of the ACC at this choke point between South America and the Antarctic Peninsula can be determined. {\ensuremath{<}}br/{\ensuremath{>}}{\ensuremath{<}}br/{\ensuremath{>}}Across the 644km section from Burdwood Bank to Elephant Island, thirty-one CTD/LADCP stations (including one test station) were made on the southbound journey with a maximum station spacing of 33km. Water samples were drawn for salinity analysis and CTD conductivity calibration. The underway measurements included: Vessel Mounted Acoustic Doppler Current Profiler, measuring currents to depths of 300m beneath the ship, navigation, sea surface temperatures recorded by thermosalinograph, meteorology logged via the oceanlogger system and Simrad echo sounder determining water depths. {\ensuremath{<}}br/{\ensuremath{>}}{\ensuremath{<}}br/{\ensuremath{>}}CTD station 32 was at the Rothera time series (RaTs) site just off Rothera Pier, carried out primarily for collected water samples for nutrient analysis back at SOC.On the northbound crossing of Drake Passage, to the west of the southbound section, an extra two full depth CTD/LADCP stations were made to test CTD DEEP03. XBTs were deployed at two hourly intervals and underway data logged. {\ensuremath{<}}br/{\ensuremath{>}}{\ensuremath{<}}br/{\ensuremath{>}}This report was compiled by Louise M. Duncan.} } @article{soton49679, volume = {73}, number = {3-4}, month = {June}, author = {S.A. Cunningham and M. Pavic}, title = {Surface geostrophic currents across the Antarctic circumpolar current in Drake Passage from 1992 to 2004}, journal = {Progress in Oceanography}, pages = {296--310}, year = {2007}, keywords = {Southern Ocean, Drake Passage, WOCE section SR1b, Antarctic circumpolar current, Surface currents, Satellite altimetry, Acoustic doppler current profiler, CTD, Southern annular mode}, url = {https://eprints.soton.ac.uk/49679/}, abstract = {The Southern Ocean plays an important role in the global overturning circulation as a significant proportion of deep water is converted into intermediate and deeper water masses in this region. Recently, a secular trend has been reported in wind stress around the Southern Ocean and it is thought theoretically that the strength of the ACC is closely related to wind stress, so one consequence should be a corresponding increase in ACC transport and hence changes in the rate of the global overturning. There are no long-term data sets of ACC transport and so we must examine other data that may also respond to changing wind stress. Here we calculate surface currents in Drake Passage every seven days over 11.25 years from 1992 to 2004. We combine surface velocity anomalies calculated from satellite altimeter sea surface heights with measured surface currents. Since 1992, the UK has regularly occupied WOCE hydrographic section SR1b across the ACC in Drake Passage. From seven hydrographic sections surface currents are estimated by referencing relative geostrophic velocities from CTD sections with current measurements made by shipboard and lowered acoustic Doppler current profilers. Combining the seven estimates of surface currents with the altimeter data reduces bias in the estimates of average currents over time through Drake Passage and we show that surface current anomalies estimated by satellite and in situ observations are in good agreement. The strongest surface currents are found in the Subantarctic and Polar Fronts with average speeds of 50 cm/s and 35 cm/s, respectively and are inversely correlated, so that maximum westward flow in one corresponds to minimum westward flow in the other. The average cross-sectional weighted surface velocity from 1992 to 2004 is 16.7 {$\pm$} 0.2 cm/s. A spectral analysis of the average surface current has only weakly increasing energy at higher frequencies and there is no dominant mode of variability. The standard deviation of the seven day currents is 0.68 cm/s and a running 12 month average has only a slightly smaller standard deviation of 0.52 {$\pm$} 0.16 cm/s. The southern annular mode (SAM) measures the circumpolar average of wind stress and like the surface currents its spectrum has slightly increased energy at frequencies greater than 1 cpy. A cospectral analysis of these, averaging cospectra of five slightly overlapping 36 month segments improve statistical reliability, suggests that there is coherence between them at 1 cpy with the currents leading changes in the Southern annular mode. We conclude that the SAM and average Drake Passage surface currents are weakly correlated with no dominant co-varying modes, and hence predicting Southern Ocean transport variability from the SAM is not likely to give significant results and that secular trends in surface currents are likely to be masked by weekly and interannual variability.} } @article{soton12680, volume = {213}, number = {3-4}, title = {A 2100 year BP record of the Pacific Decadal Oscillation, El Ni{\~n}o Southern Oscillation and Quasi-Biennial Oscillation in marine production and fluvial input from Saanich Inlet, British Columbia}, author = {J.M. Dean and A.E.S. Kemp}, year = {2004}, pages = {207--229}, journal = {Palaeogeography, Palaeoclimatology, Palaeoecology}, keywords = {diatoms, El Ni{\~n}o southern oscillation, pacific decadal oscillation, quasi-biennial oscillation, saanich Inlet, varves, laminated ediments}, url = {https://eprints.soton.ac.uk/12680/}, abstract = {Exceptional varved sediments of 2100 years BP recovered from Saanich Inlet have been analysed using high-resolution scanning electron microscopy and spectral analysis techniques. Each varve may contain up to 22 well defined individual laminae which can be attributed to seasonal-scale processes. Sediment flux comprises alternating diatom ooze/diatomaceous mud deposited during spring through autumn and a silty-clay deposited during winter. The latter may be sporadically punctuated by clay-rich laminae. Identification of some 2000 individual consecutive laminae, based on fabric and diatom assemblage, has allowed the construction of time series data for spectral analysis. Laminae types analysed include: early spring Thalassiosira spp., late spring/early summer Skeletonema costatum, multiple summer/autumn Chaetoceros spp. diatom oozes and sporadically present clay-rich winter flood deposits. Sub-decadal periods have been identified and linked to the Quasi-Biennial Oscillation (QBO) and El Ni{\~n}o Southern Oscillation (ENSO), and decadal periods to the Pacific Decadal Oscillation (PDO). Comparison of spectral analysis results with modern analogues suggests associations may exist between: early spring Thalassiosira spp. laminae and stronger La Ni{\~n}a events; late spring/early summer S. costatum laminae and El Ni{\~n}o events; summer/autumn Chaetoceros spp. multiple laminae and negative Pacific Northwest Index (PNI) regimes; and sporadically present winter clay-rich laminae and PNI-regimes. The average period for an ENSO cycle was 3.6 years, QBO 2.5 years and PDO 14.8 years. Spectral analysis of the more recent PNI record shows similar significant periods of 13.2, 3.7 and 2.6 years. Multi-decadal periods recorded include: 42.2 and 31.3 years, which might suggest multiples of PDO.} } @incollection{soton16364, month = {October}, author = {Angela Dimitrakaki}, note = {Reviewed by Susan Platt in The Art Book, 12/4, November 2005, 42-43. This is a slightly revised version of the essay under the same title published in B. Biggs, A. Dimitrakaki and J. Lamba, eds, Independent Practices: Representation, Location and History in Contemporary Visual Art, Bluecoat Arts Centre, Liverpool 2000 (NOT previously submitted to the RAE). The 'Documentary Sources in Contemporary Art' series for which this essay was selected has publsihed several influential titles, such as Art after Modernism: Rethinking Representation, edited by Brian Wallis, and Out There: Marginalisation and Contemporary Cultures, edited by R. Ferguson, M. Geever, T. Minh-ha and C. West. Contributors to the Over Here: International Perspectives on Art and Culture volume include Lee Weng Tsoy, Carlos Vidal, Gabriel Peluffo Linari, Geeta Kapur, Chang Tsong-zung, Pam Johnston, Rustom Bharucha, Carolina Ponce de Leon, Jose Manuel Valenzuela Arce, Apinan Poshyananda, Jose Luis Brea, John Clark, Marian Pastor Roces, Edouard Glissant, Everlyn Nicodemus, Kathryn Smith, Jalal Toufic, Gustavo Buntinx, Nikos Papastergiadis, Jose Gatti and Victor Tupitsyn.}, booktitle = {Over Here: International Perspectives on Art and Culture}, editor = {Jean Fisher and Gerardo Mosquera}, title = {Researching Culture/s and the Omitted Footnote: Questions on the Practice of Feminist Art History}, publisher = {The New Museum of Contemporary Art and The MIT Press}, year = {2004}, pages = {88--101}, keywords = {feminist art history, interculturalism, hegemony, globalisation, Eastern Europe, Southern Europe}, url = {https://eprints.soton.ac.uk/16364/}, abstract = {This book chapter, included in the section 'Heteroglossia: The Hermeneutic Trap', considers the function of feminist art history in an intercultural context. 'Hegemony' and 'ideology' are two of the critical concepts deployed to approach feminist art history as a subversive but also highly visible discourse on art originating in the West, the practice of which in an international context raises a number of issues concerning the power dynamics of research. 'Research' is here understood as a complex activity, positing the individual (researcher) and her subjects in a process of interaction that is necessarily ideologically bound. By using examples from her own research in Eastern and Southern Europe, the author considers the different and asymmetrical positions a feminist art historian can occupy today in diverse but interconnected social contexts that exist in a global space of material and cultural hierarchies. What can be 'translated' from one social context to another, via the practice of feminist art history, as well as those 'difficult' aspects of research often edited out of the final art historical text, are two of the key issues raised in this essay.} } @article{soton383328, volume = {94}, month = {October}, title = {An assessment of Southern Ocean water masses and sea ice during 1988?2007 in a suite of interannual CORE-II simulations}, author = {Stephanie M. Downes and Riccardo Farneti and Petteri Uotila and Stephen M. Griffies and Simon J. Marsland and David Bailey and Erik Behrens and Mats Bentsen and Daohua Bi and Arne Biastoch and Claus B{\"o}ning and Alexandra Bozec and Vittorio M. Canuto and Eric Chassignet and Gokhan Danabasoglu and Sergey Danilov and Nikolay Diansky and Helge Drange and Pier Giuseppe Fogli and Anatoly Gusev and Armando Howard and Mehmet Ilicak and Thomas Jung and Maxwell Kelley and William G. Large and Anthony Leboissetier and Matthew Long and Jianhua Lu and Simona Masina and Akhilesh Mishra and Antonio Navarra and A.J. George Nurser and Lavinia Patara and Bonita L. Samuels and Dmitry Sidorenko and Paul Spence and Hiroyuki Tsujino and Qiang Wang and Stephen G. Yeager}, year = {2015}, pages = {67--94}, journal = {Ocean Modelling}, keywords = {Southern Ocean, CORE-II experiments, Water masses, Sea ice, Ocean model intercomparison}, url = {https://eprints.soton.ac.uk/383328/}, abstract = {We characterise the representation of the Southern Ocean water mass structure and sea ice within a suite of 15 global ocean-ice models run with the Coordinated Ocean-ice Reference Experiment Phase II (CORE-II) protocol. The main focus is the representation of the present (1988?2007) mode and intermediate waters, thus framing an analysis of winter and summer mixed layer depths; temperature, salinity, and potential vorticity structure; and temporal variability of sea ice distributions. We also consider the interannual variability over the same 20 year period. Comparisons are made between models as well as to observation-based analyses where available.{\ensuremath{<}}br/{\ensuremath{>}}{\ensuremath{<}}br/{\ensuremath{>}}The CORE-II models exhibit several biases relative to Southern Ocean observations, including an underestimation of the model mean mixed layer depths of mode and intermediate water masses in March (associated with greater ocean surface heat gain), and an overestimation in September (associated with greater high latitude ocean heat loss and a more northward winter sea-ice extent). In addition, the models have cold and fresh/warm and salty water column biases centred near 50?S. Over the 1988?2007 period, the CORE-II models consistently simulate spatially variable trends in sea-ice concentration, surface freshwater fluxes, mixed layer depths, and 200?700 m ocean heat content. In particular, sea-ice coverage around most of the Antarctic continental shelf is reduced, leading to a cooling and freshening of the near surface waters. The shoaling of the mixed layer is associated with increased surface buoyancy gain, except in the Pacific where sea ice is also influential. The models are in disagreement, despite the common CORE-II atmospheric state, in their spatial pattern of the 20-year trends in the mixed layer depth and sea-ice.} } @article{soton452127, volume = {7}, month = {January}, title = {Annelid Fauna of the Prince Gustav Channel, a Previously Ice-Covered Seaway on the Northeastern Antarctic Peninsula}, author = {Regan Drennan and Thomas G. Dahlgren and Katrin Linse and Adrian G. Glover}, year = {2021}, note = {Funding Information: We would like to thank the Master and crew of RRS James Clark Ross and the scientific and technical participants of JR17003a for their support. Special thanks to Simon Dreuter for providing the bathymetric map. A special thank you also to Anton Van de Putte for their great assistance and guidance throughout the process of publishing data through biodiversity.aq. The fieldwork in the western Weddell Sea during JR17003a was undertaken under the permit No. 43/2017 issued by the Foreign and Commonwealth Office, London to section 3 of the Antarctic Act 1994. Funding. This work was supported by the National Environment Research Council grants: RD has support by the NERC INSPIRE DTP (NE/S007210/1). KL is part of the British Antarctic Survey?s Polar Science for Planet Earth Programme (NC-Science). TD was funded by the Norwegian Research Centre NORCE and the RSS James Clark Ross expedition JR17003a was funded by the NERC urgency grant NE/R012296/1 and enabled the participation of KL, AG, and TD. Funding Information: This work was supported by the National Environment Research Council grants: RD has support by the NERC INSPIRE DTP (NE/S007210/1). KL is part of the British Antarctic Survey?s Polar Science for Planet Earth Programme (NC-Science). TD was funded by the Norwegian Research Centre NORCE and the RSS James Clark Ross expedition JR17003a was funded by the NERC urgency grant NE/R012296/1 and enabled the participation of KL, AG, and TD. Publisher Copyright: {\copyright} Copyright {\copyright} 2021 Drennan, Dahlgren, Linse and Glover. Copyright: Copyright 2021 Elsevier B.V., All rights reserved.}, journal = {Frontiers in Marine Science}, keywords = {benthic, morphology, polychaeta, Southern Ocean, species checklist, taxonomy, Weddell Sea}, url = {https://eprints.soton.ac.uk/452127/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}The Prince Gustav Channel is a narrow seaway located in the western Weddell Sea on the northeastern-most tip of the Antarctic Peninsula. The channel is notable for both its deep (\>1200 m) basins, and a dynamic glacial history that most recently includes the break-up of the Prince Gustav Ice Shelf, which covered the southern portion of the channel until its collapse in 1995. However, the channel remains mostly unsampled, with very little known about its benthic biology. We present a preliminary account of the benthic annelid fauna of the Prince Gustav Channel in addition to samples from Duse Bay, a sheltered, glacier-influenced embayment in the northwestern portion of the channel. Samples were collected using an Agassiz Trawl, targeting megafaunal and large macrofaunal sized animals at depths ranging between 200?1200 m; the seafloor and associated fauna were also documented in situ using a Shallow Underwater Camera System (SUCS). Sample sites varied in terms of depth, substrate type, and current regime, and communities were locally variable across sites in terms of richness, abundance, and both taxonomic and functional composition. The most diverse family included the motile predator/scavenger Polynoidae, with 105 individuals in at least 12 morphospecies, primarily from a single site. This study provides first insights into diverse and spatially heterogeneous benthic communities in a dynamic habitat with continuing glacial influence, filling sampling gaps in a poorly studied region of the Southern Ocean at direct risk from climate change. These specimens will also be utilized in future molecular investigations, both in terms of describing the genetic biodiversity of this site and as part of wider phylogeographic and population genetic analyses assessing the connectivity, evolutionary origins, and demographic history of annelid fauna in the region.{\ensuremath{<}}/p{\ensuremath{>}}} } @misc{soton487238, title = {Data supporting University of Southampton Doctoral Thesis entitled: Patterns of diversity, connectivity, and evolution in southern ocean and deep-sea annelids}, author = {Regan Drennan and Adrian G Glover and Jon Copley and Katrin Linse and Thomas G Dahlgren and Sergio Taboada and Maria Belen Arias}, publisher = {University of Southampton}, year = {2024}, keywords = {ddRADseq, population genomics, Annelida, Antarctica, biodiversity, Southern Ocean, Deep Sea, Deep-sea mining, population genetics, species delimitation, Polychaeta, DNA barcoding}, url = {https://eprints.soton.ac.uk/487238/}, abstract = {{\ensuremath{<}}span style='white-space:pre-line'{\ensuremath{>}}Data supporting University of Southampton Doctoral Thesis entitled: Patterns of diversity, connectivity, and evolution in southern ocean and deep-sea annelids (2024) by Regan Drennan See README for detail of each dataset. Data includes genomic data (Single Nucleotide Polymorphism (SNP) catalogs), held externally on ZENODO due to file size (DOI: 10.5281/zenodo.10606641). {\ensuremath{<}}/span{\ensuremath{>}}} } @article{soton367638, volume = {104}, month = {June}, title = {A comparison of megafaunal communities in five submarine canyons off Southern California, USA}, author = {Grant A. Duffy and Lonny Lundsten and Linda A. Kuhnz and Charles K. Paull}, year = {2014}, pages = {259--266}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Community composition, Deep sea, Hueneme, La Jolla, Mugu, Redondo, ROVs, Santa Monica, Southern California, Submarine canyons}, url = {https://eprints.soton.ac.uk/367638/}, abstract = {Remotely operated vehicle surveys were conducted in five submarine canyons off Southern California during research expeditions in 2005 and 2010. Video transects from a range of depths were analysed to produce presence/absence data of megafauna for each site. A comparison of benthic communities at various depths, locales, and canyons was performed. No significant difference was found between canyon communities based on the level of sediment transport activity, however this may be due to the unbalanced sampling of this opportunistic study. There was significant variation in biological community composition and abundance amongst water depths. These depth-related trends are in agreement with the findings of the previous studies and are likely tied to depth-correlated variables such as hydrostatic pressure, temperature, salinity, and oxygen concentration. Species richness was found to initially increase with depth before declining rapidly at the mouths of the studied canyons. Low oxygen levels in the Santa Monica Basin, into which four of the surveyed canyons empty, may explain this.} } @article{soton63081, volume = {113}, number = {C7}, month = {July}, author = {K. D{\"o}{\"o}s and J. Nycander and A.C. Coward}, title = {Lagrangian decomposition of the Deacon Cell}, journal = {Journal of Geophysical Research}, pages = {C07028}, year = {2008}, keywords = {Deacon Cell, Southern Ocean, Lagrangian trajectories}, url = {https://eprints.soton.ac.uk/63081/}, abstract = {The meridional overturning cells in the Southern Ocean are decomposed by Lagrangian tracing using velocity and density fields simulated with an ocean general circulation model. Particular emphasis is given to the Deacon Cell. The flow is divided into four major components: (1) water circling around Antarctica in the Antarctic Circumpolar Current (ACC), (2) water leaving the ACC toward the north into the three world oceans, (3) water coming from the north and joining the ACC, mainly consisting of North Atlantic Deep Water (NADW), and (4) interocean exchange between the three world oceans without circling around Antarctica. The Deacon Cell has an amplitude of 20 Sv, of which 6 Sv can be explained by the east-west tilt of the ACC, 5 Sv by the east-west tilt of the subtropical gyre, and the remaining 9 Sv by the differences of the slope and depth of the southward transport of NADW and its return flow as less dense water. The diabatic or cross-isopycnal Deacon Cell is only 2 Sv.} } @article{soton367440, volume = {89}, month = {July}, title = {Particle flux characterisation and sedimentation patterns of protistan plankton during the iron fertilisation experiment LOHAFEX in the Southern Ocean}, author = {Friederike Ebersbach and Philipp Assmy and Patrick Martin and Isabelle Schulz and Sina Wolzenburg and Eva-Maria N{\"o}thig}, year = {2014}, pages = {94--103}, journal = {Deep Sea Research Part I: Oceanographic Research Papers}, keywords = {Nano- and picoplankton, Export flux, Iron fertilisation, Protists, Sediment trap, Southern Ocean}, url = {https://eprints.soton.ac.uk/367440/}, abstract = {The taxonomic composition and types of particles comprising the downward particle flux were examined during the mesoscale artificial iron fertilisation experiment LOHAFEX. The experiment was conducted in low-silicate waters of the Atlantic Sector of the Southern Ocean during austral summer (January?March 2009), and induced a bloom dominated by small flagellates. Downward particle flux was low throughout the experiment, and not enhanced by addition of iron; neutrally buoyant sediment traps contained mostly faecal pellets and faecal material apparently reprocessed by mesozooplankton. TEP fluxes were low, ?5 mg GX eq. m?2 d?1, and a few phytodetrital aggregates were found in the sediment traps. Only a few per cent of the POC flux was found in the traps consisting of intact protist plankton, although remains of taxa with hard body parts (diatoms, tintinnids, thecate dinoflagellates and foraminifera) were numerous, far more so than intact specimens of these taxa. Nevertheless, many small flagellates and coccoid cells, belonging to the pico- and nanoplankton, were found in the traps, and these small, soft-bodied cells probably contributed the majority of downward POC flux via mesozooplankton grazing and faecal pellet export. TEP likely played an important role by aggregating these small cells, and making them more readily available to mesozooplankton grazers.} } @misc{soton445093, volume = {25}, number = {13}, month = {December}, author = {Rosalind Edwards and Helen Moewaka Barnes and Deborah McGregor and Tula Brannelly}, title = {Supporting indigenous and non-indigenous research partnerships}, journal = {The Qualitative Report}, pages = {6--15}, year = {2020}, keywords = {Indigenous and non-Indigenous research partnerships; Northern epistemology; Southern epistemologies; Indigenous methodologies; decolonized collaborative practice}, url = {https://eprints.soton.ac.uk/445093/}, abstract = {This commentary discusses the framing of the production of a series of online text-based and visual resources aimed at researchers embarking on Indigenous and non-Indigenous research partnerships, and in particular supporting non-Indigenous researchers to think about our/their methods, assumptions and behaviour. We identify the tension in mainstream funding for such partnerships, and discuss the implications of Northern epistemological claims to agendas and universality as against Southern epistemologies acknowledging diversity and challenging oppressions. We note the distinct bases for Indigenous methodologies. Our commentary outlines and illustrates the online downloadable resources produced by our own Indigenous and non-Indigenous research partnership, including a video/audio recording, a comic, and blog posts, addressing decolonized collaborative practice.} } @article{soton49681, volume = {30}, number = {7}, month = {June}, author = {G.F. Esteban and A.J. Gooday and K.J. Clarke}, title = {Siliceous scales of filose-amoebae (Pompholyxophryidae, Rotosphaerida) from deep Southern Ocean sediments, including first records for the Southern Hemisphere}, journal = {Polar Biology}, pages = {945--950}, year = {2007}, keywords = {Antarctica, Biogeography, Heliozoa, Scale-bearing protists, South Sandwich Islands, Southern Hemisphere}, url = {https://eprints.soton.ac.uk/49681/}, abstract = {The world of protists remains largely unexplored. A thorough electron-microscopic investigation of a few microlitres of deep-sea sediment from 2,964 m water depth near the South Sandwich Islands (Southern Ocean) revealed siliceous scales of filose-amoeba protist species, two of which have not been reported previously from Antarctica or from elsewhere in the Southern Hemisphere. However, all the species are known from other oceans and, in one case, from freshwater habitats. The Antarctic protistan scales belong to four species of filose amoebae: Pinaciophora fluviatilis Greef 1869, Pinaciophora denticulata Thomsen 1978, Pinaciophora multicosta Thomsen 1978 and Rabdiaster reticulata (Thomsen 1979) Mikrjukov 1999 nov. comb. Our study shows that (1) none of the species has been recorded from the Australasian biogeograpical region, (2) Pinaciophora multicosta and Rabdiaster reticulata are new records for the Southern Ocean and for the Southern Hemisphere as a whole, (3) prior to this investigation, Pinaciophora multicosta had been reported once only, from the Baltic Sea (Europe). These results highlight the problem of undersampling in the study of the global distribution of protists.} } @article{soton372139, volume = {119}, number = {11}, month = {November}, author = {Dafydd Gwyn Evans and Jan D. Zika and Alberto C. Naveira Garabato and A.J. George Nurser}, title = {The imprint of Southern Ocean overturning on seasonal water mass variability in Drake Passage}, journal = {Journal of Geophysical Research}, pages = {7987--8010}, year = {2014}, keywords = {southern ocean overturning, drake passage, water masses, thermohaline coordinates, in situ observations}, url = {https://eprints.soton.ac.uk/372139/}, abstract = {Seasonal changes in water mass properties are discussed in thermohaline coordinates from a seasonal climatology and repeat hydrographic sections. The SR1b CTD transects along Drake Passage are used as a case study. The amount of water within temperature and salinity classes and changes therein are used to estimate dia-thermal and dia-haline transformations. These transformations are considered in combination with climatologies of surface buoyancy flux to determine the relative contributions of surface buoyancy fluxes and subsurface mixing to changes in the distribution of water in thermohaline coordinates. The framework developed provides unique insights into the thermohaline circulation of the water masses that are present within Drake Passage, including the erosion of Antarctic Winter Water (AAWW) during the summer months and the interaction between the Circumpolar Deep Waters (CDW) and Antarctic Intermediate Water (AAIW). The results presented are consistent with summertime wind-driven inflation of the CDW layer and deflation of the AAIW layer, and with new AAIW produced in the winter as a mixture of CDW, remnant AAWW, and surface waters. This analysis therefore highlights the role of surface buoyancy fluxes in the Southern Ocean overturning.} } @article{soton381303, volume = {93}, month = {September}, title = {An assessment of Antarctic Circumpolar Current and Southern Ocean Meridional Overturning Circulation during 1958?2007 in a suite of interannual CORE-II simulations}, author = {Riccardo Farneti and Stephanie M. Downes and Stephen M. Griffies and Simon J. Marsland and Erik Behrens and Mats Bentsen and Daohua Bi and Arne Biastoch and Claus B{\"o}ning and Alexandra Bozec and Vittorio M. Canuto and Eric Chassignet and Gokhan Danabasoglu and Sergey Danilov and Nikolay Diansky and Helge Drange and Pier Giuseppe Fogli and Anatoly Gusev and Robert W. Hallberg and Armando Howard and Mehmet Ilicak and Thomas Jung and Maxwell Kelley and William G. Large and Anthony Leboissetier and Matthew Long and Jianhua Lu and Simona Masina and Akhilesh Mishra and Antonio Navarra and A.J. George Nurser and Lavinia Patara and Bonita L. Samuels and Dmitry Sidorenko and Hiroyuki Tsujino and Petteri Uotila and Qiang Wang and Steve G. Yeager}, year = {2015}, pages = {84--120}, journal = {Ocean Modelling}, keywords = {Global ocean?sea ice modeling, Model comparisons, Southern Ocean meridional overturning circulation, Antarctic Circumpolar Current, Southern Ocean dynamics}, url = {https://eprints.soton.ac.uk/381303/}, abstract = {In the framework of the second phase of the Coordinated Ocean-ice Reference Experiments (CORE-II), we present an analysis of the representation of the Antarctic Circumpolar Current (ACC) and Southern Ocean meridional overturning circulation (MOC) in a suite of seventeen global ocean?sea ice models. We focus on the mean, variability and trends of both the ACC and MOC over the 1958?2007 period, and discuss their relationship with the surface forcing. We aim to quantify the degree of eddy saturation and eddy compensation in the models participating in CORE-II, and compare our results with available observations, previous fine-resolution numerical studies and theoretical constraints. Most models show weak ACC transport sensitivity to changes in forcing during the past five decades, and they can be considered to be in an eddy saturated regime. Larger contrasts arise when considering MOC trends, with a majority of models exhibiting significant strengthening of the MOC during the late 20th and early 21st century. Only a few models show a relatively small sensitivity to forcing changes, responding with an intensified eddy-induced circulation that provides some degree of eddy compensation, while still showing considerable decadal trends. Both ACC and MOC interannual variabilities are largely controlled by the Southern Annular Mode (SAM). Based on these results, models are clustered into two groups. Models with constant or two-dimensional (horizontal) specification of the eddy-induced advection coefficient ? show larger ocean interior decadal trends, larger ACC transport decadal trends and no eddy compensation in the MOC. Eddy-permitting models or models with a three-dimensional time varying ? show smaller changes in isopycnal slopes and associated ACC trends, and partial eddy compensation. As previously argued, a constant in time or space ? is responsible for a poor representation of mesoscale eddy effects and cannot properly simulate the sensitivity of the ACC and MOC to changing surface forcing. Evidence is given for a larger sensitivity of the MOC as compared to the ACC transport, even when approaching eddy saturation. Future process studies designed for disentangling the role of momentum and buoyancy forcing in driving the ACC and MOC are proposed.} } @article{soton28711, volume = {53}, number = {2}, title = {Development of a robust ecosystem model to predict the role of iron on biogeochemical cycles: a comparison of results for iron-replete and iron-limited areas, and the SOIREE iron-enrichment experiment}, author = {M.J.R. Fasham and K.J. Flynn and P. Pondaven and T.R. Anderson and P.W. Boyd}, year = {2006}, pages = {333--366}, journal = {Deep Sea Research Part I: Oceanographic Research Papers}, keywords = {ecosystem model, iron limitation, diatom growth, carbon budgets, nutrient cycles, export flux, Southern Ocean, Kerguelen Islands time-series station, SOIREE site, North Atlantic, Biotrans station}, url = {https://eprints.soton.ac.uk/28711/}, abstract = {A new mixed layer multi-nutrient ecosystem model, incorporating diatoms, non-diatoms and zooplankton, is described that models the role of iron in marine biogeochemical cycles. The internal cell biochemistry of the phytoplankton is modelled using the mechanistic model of Flynn [2001. A mechanistic model for describing dynamic multi-nutrient, light, temperature interactions in phytoplankton. Journal of Plankton Research 23, 977?997] in which the internal cell concentrations of chlorophyll, nitrogen, silica, and iron are all dynamic variables that respond to external nutrient concentrations and light levels. Iron stress in phytoplankton feeds back into chlorophyll synthesis and changes in photosynthetic unit (PSU) size, thereby reducing their growth rate. Because diatom silicon metabolism is inextricably linked with cell division, diatom population density (cell m?3) is modelled as well as C biomass. An optimisation technique was used to fit the model to three time-series datasets at Biotrans (47?N, 20?W) and Kerfix (50?40?S, 68?25?E) and the observations for the Southern Ocean Iron-Release Experiment (SOIREE) iron-enrichment experiment (61?S, 140?E). The model gives realistic simulations of the annual cycles of nutrients, phytoplankton, and primary production at Biotrans and Kerfix and can also accurately simulate an iron fertilisation experiment. Specifically, the model predicts the high values of diatom Si:N and Si:C ratios observed in areas where iron is a limiting factor on algal growth. In addition, the model results at Kerfix confirm previous suggestions that underwater light levels have a more limiting effect on phytoplankton growth than iron supply. The model is also used to calculate C budgets and C and Si export from the mixed layer. The implications of these results for developing biogeochemical models incorporating the role of iron are discussed.} } @article{soton413899, volume = {57}, number = {3}, month = {March}, author = {Y. Feng and C.E. Hare and J.M. Rose and S.M. Handy and G.R. DiTullio and P.A. Lee and W.O. Smith and J. Peloquin and S. Tozzi and J. Sun and Y. Zhang and R. B. Dunbar and M.C. Long and B. Sohst and M. Lohan and D.A. Hutchins}, title = {Interactive effects of iron, irradiance and CO{\ensuremath{<}}sub{\ensuremath{>}}2{\ensuremath{<}}/sub{\ensuremath{>}} on Ross Sea phytoplankton}, journal = {Deep Sea Research Part I: Oceanographic Research Papers}, pages = {368--383}, year = {2010}, keywords = {Co-limitation, CO, Diatoms, Global change, Interactive effects, Iron limitation, Irradiance, Phaeocystis, Phytoplankton, Ross Sea, Southern Ocean}, url = {https://eprints.soton.ac.uk/413899/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}We conducted a factorial shipboard continuous culture experiment to examine the interactive effects of altered iron, irradiance and CO{\ensuremath{<}}sub{\ensuremath{>}}2{\ensuremath{<}}/sub{\ensuremath{>}} on the summer phytoplankton community of the Ross Sea, Antarctica. After 18 days of continuous incubation, iron enrichment increased phytoplankton biomass, nutrient drawdown, diatom and Phaeocystis abundance, and some photosynthetic parameters. High irradiance significantly increased the number of Phaeocystis antarctica colonies, as well as P. antarctica abundance relative to diatoms. Iron and light had significant interactive effects on diatom and P. antarctica pigment concentrations, P. antarctica colony abundance, and Si:N, Si:C, and N:P ratios. The major influence of high CO{\ensuremath{<}}sub{\ensuremath{>}}2{\ensuremath{<}}/sub{\ensuremath{>}} was on diatom community structure, by favoring the large centric diatom Chaetoceros lineola over the small pennate species Cylindrotheca closterium. The ratio of centric to pennate diatoms was significantly responsive to changes in all three variables individually, and to all of their possible two- and three-way combinations. These results suggest that shifts in light, iron, and CO{\ensuremath{<}}sub{\ensuremath{>}}2{\ensuremath{<}}/sub{\ensuremath{>}} and their mutual interactions all play a role in controlling present day Ross Sea plankton community structure, and need to be considered when predicting the possible future responses of biology and biogeochemistry in this region.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton458190, volume = {49}, number = {11}, month = {June}, author = {Bieito Fern{\'a}ndez Castro and Matthew Mazloff and Richard G. Williams and Alberto C. Naveira Garabato}, note = {Funding Information: This research was funded by European Union's Horizon 2,020 research and innovation program under the Marie Sk{\l}odowska?Curie grant agreement No. 834330 (SO?CUP) to BFC. RGW was supported by NERC Grant No. NE/T010657/1. Float data were collected and made freely available by the Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM) Project funded by the National Science Foundation, Division of Polar Programs (NSF PLR?1425989, with extension NSF OPP?1936222), supplemented by NASA, and by the International Argo Program and the NOAA programs that contribute to it. Publisher Copyright: {\copyright} 2022. The Authors.}, title = {Subtropical contribution to sub?Antarctic mode waters}, journal = {Geophysical Research Letters}, year = {2022}, keywords = {Southern Ocean, Sub-Antartic Mode Water, biogeochemical Argo float, mixed layer, preformed nutrients, subtropical gyre}, url = {https://eprints.soton.ac.uk/458190/}, abstract = {Sub-Antarctic Mode Waters (SAMW) form to the north of the Antarctic Circumpolar Current (ACC) through deep winter mixing. SAMW connect the atmosphere with the oceanic pycnocline, transferring heat and carbon into the ocean interior and supplying nutrients to the northern ocean basins. The processes controlling SAMW ventilation and properties remain poorly understood. Here, we investigate the significance and origin of a ubiquitous feature of SAMW formation regions: The seasonal build-up of a subsurface salinity maximum. With biogeochemical Argo floats, we show that this feature influences SAMW mixed-layer dynamics, and that its formation is associated with a decline in preformed nutrients comparable to biological drawdown in surface waters ({$\sim$}0.15 mol m?2 y?1). Our analysis reveals that these features are driven by advection of warm, salty, nutrient-poor waters of subtropical origin along the ACC. This influx represents a leading-order term in the SAMW physical and biogeochemical budgets, and can impact large-scale nutrient distributions.} } @article{soton49514, volume = {54}, number = {18-20}, month = {September}, author = {Sophie Fielding and Peter Ward and Raymond T. Pollard and Sophie Seeyave and Jane F. Read and J. Alan Hughes and Tania Smith and Claudia Castellani}, title = {Community structure and grazing impact of mesozooplankton during late spring/early summer 2004/2005 in the vicinity of the Crozet Islands (Southern Ocean)}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, pages = {2106--2125}, year = {2007}, keywords = {southern ocean, zooplankton, abundance, community composition, drepanopus pectinatus}, url = {https://eprints.soton.ac.uk/49514/}, abstract = {Net sampling within the vicinity of the Crozet archipelago, in the Indian Ocean sector of the Southern Ocean, was conducted during late spring/summer (November 2004?January 2005) to describe the composition, distribution and grazing impact of mesozooplankton, and to investigate their relationships with the prevailing oceanographic regime in the area. The mesozooplankton community was intimately linked with the large-scale physical circulation in the region. To the west and north of the Islands, the sub-Antarctic Front (SAF) presented a strong biogeographic boundary between sub-tropical and sub-Antarctic species. South and east of the SAF, the mesozooplankton community was dominated by Polar Frontal Zone (PFZ) copepod species. Cluster analysis of mesozooplankton abundance data identified two main communities in the PFZ, termed here Island and Oceanic. Island stations, representing the proposed iron-fertilised productive region north of the archipelago, contained an abundance (mean of 2269 ind m?3) of the neritic copepod Drepanopus pectinatus, whose presence indicated that the water had interacted with the Crozet Island shelf at some point. D. pectinatus was present in samples north of Crozet up to the SAF, confirming that water passing the Crozet Islands could be transported throughout the region to the north. The Oceanic stations, south of the Islands and within the SAF, contained similar mesozooplankton abundances and biovolume to the Island stations suggesting little enhanced impact of the iron-fertilised phytoplankton bloom through the mesozooplankton food web.{\ensuremath{<}}br/{\ensuremath{>}}{\ensuremath{<}}br/{\ensuremath{>}}Copepod community grazing pressure, in both Island and Oceanic stations, during November and December was small (\<7\% of chlorophyll-a standing stock per day, \<35\% primary production per day). By January, a phytoplankton bloom had developed at some of the Island stations (up to 3000 mg C m?2 d?1) and grazing pressure was \<1\% of chlorophyll-a standing stock per day. At the oceanic stations, primary productivity had reduced from 460 to 200 mg C m?2 d?1, typical values for high-nutrient low-chlorophyll (HNLC) waters, and the copepod community grazing pressure had increased to 90\% of daily primary productivity. This suggests that a combination of grazing and micronutrient availability controls phytoplankton biomass in HNLC waters to the south of Crozet, while grazing had little impact on the ?iron-fertilised? bloom north of the Crozet Islands. The intense seasonal phytoplankton bloom around Crozet may therefore be exported to the sea floor rather than fuelling the higher trophic levels. {\ensuremath{<}}br/{\ensuremath{>}}{\ensuremath{<}}br/{\ensuremath{>}}} } @article{soton192421, volume = {38}, number = {2}, month = {February}, author = {Shu Gao and Michael Collins}, title = {Tidal Inlet Equilibrium, in Relation to Cross-sectional Area and Sediment Transport Patterns}, journal = {Estuarine, Coastal and Shelf Science}, pages = {157--172}, year = {1994}, keywords = {tidal inlets, equilibrium, sediment transport, southern China coast, southern England coast}, url = {https://eprints.soton.ac.uk/192421/}, abstract = {Equilibrium cross-sectional area is a crucial parameter in the assessment of the stability of tidal inlets; it has been related to tidal prism, through the empirical O'Brien method. Analyses presented here, based upon equations associated with equilibrium, show that other factors (i.e. not tidal prism alone) are also important: (1) flood and ebb tidal durations; (2) freshwater discharges; and (3) sediment transport through the entrance. Analytical approaches are suggested for evaluating tidal inlet equilibrium conditions. The method can be applied to analyse the equilibrium of individual inlets, reducing errors in the application of the O'Brien method. Equilibrium conditions for inlet systems at Langstone Harbour (southern England) and Yangpu Harbour (southern China) are compared, suggesting some deviation from the conclusion that maximum cross-sectional mean current speed for a stable inlet should be around 1?0 m s-1.} } @article{soton421224, volume = {31}, number = {2}, month = {June}, author = {Leonardo Garc{\'i}a Sanju{\'a}n and Juan Manuel Vargas Jim{\'e}nez and Luis C{\'a}ceres Puro and Manuel Eleazar Costa Caram{\'e} and Marta Diaz-Guardamino Uribe and Marta D{\'i}az-Zorita Bonilla and {\'A}lvaro Fern{\'a}ndez Flores and V{\'i}ctor Hurtado P{\'e}rez and Pedro M L{\'o}pez Aldana and Elena M{\'e}ndez Izquierdo and Ana Pajuelo Pando and Joaqu{\'i}n Rodr{\'i}guez Vidal and David W. Wheatley and Christopher Bronk Ramsey and Antonio Delgado-Huertas and Elaine Dunbar and Adri{\'a}n Mora Gonz{\'a}lez and Alex Bayliss and Derek Hamilton and Alasdair Whittle}, title = {Assembling the dead, gathering the living: radiocarbon dating and Bayesian modelling for Copper Age Valencina de la Concepci{\'o}n (Sevilla, Spain)}, journal = {Journal of World Prehistory}, pages = {179--313}, year = {2018}, keywords = {Southern Iberia, Copper Age, settlement, mortuary practice, radiocarbon dating, formal chronological modelling, social change}, url = {https://eprints.soton.ac.uk/421224/}, abstract = {The great site of Valencina de la Concepci{\'o}n, near Seville in the lower Guadalquivir valley of south-west Spain, is presented in the context of debate about the nature of Copper Age society in southern Iberia as a whole. Many aspects of the layout, use, character and development of Valencina remain unclear, just as there are major unresolved questions about the kind of society represented there and in southern Iberia, from the late fourth to the late third millennia cal BC. This paper discusses 178 radiocarbon dates, from 17 excavated sectors within the 450ha site, making it the best dated in later Iberian prehistory as a whole. Dates are formally modelled in a Bayesian statistical framework. The bulk of samples were chosen from the varied mortuary contexts, from pits and artificial caves to megalithic tholos tombs, which constitute a major part of the archaeology of Copper Age Valencina. The resulting formal date estimates provide the basis for both a new epistemological approach to the site as well as a much more detailed narrative of its development than previously available. Beginning in the 32nd century cal BC, a long-lasting tradition of simple, mainly collective and often successive burial was established at the site. There is plenty of evidence for a wide range of other activity, but no clear sign of permanent, large-scale residence or public buildings or spaces. Probably by the 30th or 29th century cal BC, a new form of mortuary practice had emerged alongside older traditions, in the shape of the distinctive megalithic tholos tombs, some of which contained exotic and abundant goods accompanying the dead. Though the models lack precision, this phase of showy funerals and social display, perhaps aimed at establishing new forms of descent and social hierarchisation partly based on the manipulation of the past, may not have lasted much beyond the 28th century cal BC. It is possible that activity as a whole had declined before the middle of the third millennium cal BC, and around 2500 cal BC, dated sectors indicate further changes in mortuary practice, with possible single events, containing in one instance signs of defleshing (perhaps associated with violence); by this date, Bell Beaker pottery was present on the site. Major monuments, such as La Pastora and Matarrubilla were probably also late constructions. At least some of the ditches known at the site probably also belong late in the sequence. Overall, a pattern is indicated of initial establishment and consolidation of mortuary tradition, followed by the emergence of the more elaborate tholos architecture and the sometimes exotic contents. Funerary activity probably declined in intensity in the second quarter of the third millennium cal BC but was followed by a resurgence including the construction of the grand tholos of La Pastora in the generations around 2500 cal BC. This resurgence was relatively brief and the intensive funerary activity probably ended during the 24th century cal BC. Results in general support a model of increasingly competitive but ultimately unstable social relations.} } @article{soton1318, volume = {105}, number = {1/2}, title = {Offshore continuation of volcanic rift zones, El Hierro, Canary Islands}, author = {M.J.R. Gee and D.G. Masson and A.B. Watts and N.C. Mitchell}, year = {2001}, pages = {107--119}, journal = {Journal of Volcanology and Geothermal Research}, keywords = {Canary Islands, El Hierro, flank rift zones, Southern Ridge .}, url = {https://eprints.soton.ac.uk/1318/}, abstract = {El Hierro is the youngest and most southwesterly of the seven Canary islands. The established view, based on subaerial geology, is that El Hierro is a classic example of an oceanic island with 120? ?? spaced volcanic rift arms (VRZs) forming a "mercedes star". However, new offshore data do not support this simple interpretation. Instead of the discrete ridges of VRZs, we observe (to the NW and NE) broad areas of irregular morphology, which suggest that rifting activity might not be confined to narrow zones. Furthermore, our data suggest that the anomalously long and steep-flanked Southern Ridge could be part of an older, eroded volcanic edifice that predates much of the other submarine flanks of El Hierro. The Southern Ridge has a distinctive gullied morphology, which strongly contrasts with adjacent flanks. There is also a {\texttt{\char126}}400-m-deep saddle in its longitudinal profile 15 km from the coastline, which we interpret as evidence that the Southern Ridge did not form by continuous dyke intrusion from the El Hierro volcanic centre. South of the saddle, mean flank slopes are 10? steeper ({\texttt{\char126}}30?) with a sharp slope break at 3700 m between the ridge and smoothly sedimented seafloor. These steeper slopes and lack of landslide scars to the south of the saddle indicate that the Southern Ridge is a stable edifice, relative to the rest of El Hierro. Surrounding sediments to the southeast appear to onlap the Southern Ridge. A large landslide deposit, El Julan (estimated age \>200 ka), occurs to the west of the ridge. This landslide appears to have been constrained from spreading southeastwards by the Southern Ridge, resulting in an elevation difference of 300 m for the seafloor on either side of the ridge.} } @article{soton486662, volume = {30}, number = {1}, month = {January}, author = {M{\'i}riam Gimeno and Joan Gim{\'e}nez and Andre Chiaradia and Lloyd S. Davis and Philip J. Seddon and Yan Ropert-Coudert and Ryan R. Reisinger and Marta Coll and Francisco Ram{\'i}rez}, note = {Funding Information: We want to thank Teresa Milit{\~a}o for providing valuable suggestions on earlier drafts of the draft. Thanks to Isabel Af{\'a}n for helping to perform the analyses and Aina Llorca for drawing the penguins' silhouettes. We also thank all the scientists, students and field assistants from the RAATD project who helped collect data in the field or process them. We also thank the Phillip Island Nature Parks for continuing long?term support to penguin research. This work acknowledges the Spanish government through the ?Severo Ochoa Centre of Excellence? accreditation (CEX2019?000928?S, ICM?CSIC), the project SOSPEN (Spanish National Plan for Scientific and Technical Research and Innovation, 2021, PID2021?124831OA?I00), the project SEASentinels (Spanish National Plan for Scientific and Technical Research and Innovation, 2023, CNS2022?135631), the project ProOceans (Spanish National Plan for Scientific and Technical Research and Innovation, 2020, PID2020?118097RB?I00) and the EU project TRIATLAS (Grant Agreement No. 817578) and Ges4Seas (Grant Agreement 101059877). This work hopes to contribute to the IUCN Penguin Specialist Group's mission towards wild penguins in perpetuity. FR and JG were supported by Ram{\'o}n y Cajal and Juan de la Cierva?Formaci{\'o}n programmes (Spanish Ministerio de Ciencia e Innovaci{\'o}n, RYC2020?030078?I and FJC2019?040016?I), respectively. MG was granted with a JAE Intro SOMdM (JAE?SOMdM21?80) and supported by FPI?SO fellowship (CEX2019?000928?S?20?1).}, title = {Climate and human stressors on global penguin hotspots: current assessments for future conservation}, journal = {Global Change Biology}, year = {2024}, keywords = {environmental trends, fisheries, global change, human pressures, marine systems, sentinels, Southern Hemisphere, threats}, url = {https://eprints.soton.ac.uk/486662/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}As charismatic and iconic species, penguins can act as ?ambassadors? or flagship species to promote the conservation of marine habitats in the Southern Hemisphere. Unfortunately, there is a lack of reliable, comprehensive, and systematic analysis aimed at compiling spatially explicit assessments of the multiple impacts that the world's 18 species of penguin are facing. We provide such an assessment by combining the available penguin occurrence information from Global Biodiversity Information Facility (\>800,000 occurrences) with three main stressors: climate-driven environmental changes at sea, industrial fisheries, and human disturbances on land. Our analyses provide a quantitative assessment of how these impacts are unevenly distributed spatially within species' distribution ranges. Consequently, contrasting pressures are expected among species, and populations within species. The areas coinciding with the greatest impacts for penguins are the coast of Per{\'u}, the Patagonian Shelf, the Benguela upwelling region, and the Australian and New Zealand coasts. When weighting these potential stressors with species-specific vulnerabilities, Humboldt (Spheniscus humboldti), African (Spheniscus demersus), and Chinstrap penguin (Pygoscelis antarcticus) emerge as the species under the most pressure. Our approach explicitly differentiates between climate and human stressors, since the more achievable management of local anthropogenic stressors (e.g., fisheries and land-based threats) may provide a suitable means for facilitating cumulative impacts on penguins, especially where they may remain resilient to global processes such as climate change. Moreover, our study highlights some poorly represented species such as the Northern Rockhopper (Eudyptes moseleyi), Snares (Eudyptes robustus), and Erect-crested penguin (Eudyptes sclateri) that need internationally coordinated efforts for data acquisition and data sharing to understand their spatial distribution properly.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton11043, volume = {32}, number = {8}, title = {El Nino-Southern Oscillation signal associated with middle Holocene climate change in intercorrelated terrestrial and marine sediment cores, North Island, New Zealand}, author = {Basil Gomez and Lionel Carter and Noel A. Trustrum and Alan S. Palmer and Andrew P. Roberts}, year = {2004}, pages = {653--656}, journal = {Geology}, keywords = {climate change, El Ni{\~n}o?Southern Oscillation, landsliding, New Zealand}, url = {https://eprints.soton.ac.uk/11043/}, abstract = {A synchronous textural variation in intercorrelated, high-resolution sediment records from floodplain, continental-shelf, and continental-slope settings of the eastern North Island, New Zealand, provides evidence of increased storminess after ca. 4 ka. An upcore change in sediment texture reflects the transition to landsliding, which supplanted fluvial incision as the dominant mode of sediment production in the middle Holocene. This signal, which appears in all three records, indicates a regional response to external forcing and records the impact of an intensified atmospheric circulation marking the establishment of the contemporary climate that is strongly influenced by the El Ni{\~n}o?Southern Oscillation. The change in climate was a hemispheric event, and in the Southern Hemisphere its timing is confirmed by independent proxy records from elsewhere in New Zealand and the circum?South Pacific region.} } @article{soton355813, volume = {21}, number = {6}, title = {Long-term development of a cultural landscape: the origins and dynamics of lowland heathland in southern England}, author = {Jon A. Groves and Martyn P. Waller and Michael J. Grant and J. Edward Schofield}, year = {2012}, pages = {453--470}, journal = {Vegetation History and Archaeobotany}, keywords = {Pollen analysis, Lowland heath, Human impact, Pinus, Southern England, Microscopic charcoal}, url = {https://eprints.soton.ac.uk/355813/}, abstract = {The lowland heathlands of southern England comprise ca. 14\% of the total area of this habitat in Europe yet their history is poorly understood. This paper presents the first detailed palaeoecological evidence (combining palynological, microscopic charcoal and radiocarbon data) relating to the origin and long-term dynamics of heathland vegetation in southern England. Valley peat sites, situated on the Lower Greensand Group (coarse-grained sandstones) at Conford (Hampshire) and Hurston Warren (West Sussex) have been investigated. The sequence from Conford indicates the unusually late survival of Pinus sylvestris (to as late as ca. 6050 cal. B.P.) in southern England. This is attributed to edaphic factors and, after ca. 7050 cal. B.P., to frequent fires. After intervening phases of dominance by deciduous woodland, heathland vegetation became established in the proximity of both sites in the Late Bronze Age (ca. 3000 cal. B.P.) with increases in indicators of grazing and burning demonstrating an association between the development of heathland and human activity. Thereafter, the pollen and charcoal records show that the vegetation remained in a dynamic state as the scale and nature of human activity varied through time. Major expansions in the extent of heathland occurred relatively recently; after ca. 1450 cal. B.P. at Hurston Warren and after ca. 850 cal. B.P. at Conford. A review of the palaeoecological evidence suggests that the most intense use and greatest coverage of heathland in southern England probably occurred during the medieval to post-medieval periods.} } @article{soton65638, volume = {7}, number = {2}, title = {Child dysentery in the Limpopo Valley: a cohort study of water, sanitation and hygiene risk factors}, author = {Stephen W. Gundry and James A. Wright and Ron{\'a}n M. Conroy and Martella du Preez and Bettina Genthe and Sibonginkosi Moyo and Charles Mutisi and Natasha Potgieter}, year = {2009}, pages = {259--266}, journal = {Journal of Water and Health}, keywords = {diarrhoea, dysentery, risk factors, southern africa, water microbiology}, url = {https://eprints.soton.ac.uk/65638/}, abstract = {The objective of this cohort study was to assess risk factors for child dysentery and watery diarrhoea. The study participants consisted of 254 children aged 12?24 months in rural South{\ensuremath{<}}br/{\ensuremath{>}}Africa and Zimbabwe in households where drinking water was collected from communal sources. The main outcome measure was the most severe diarrhoea episode: dysentery, watery diarrhoea or none. For dysentery, drinking water from sources other than standpipes had a relative risk ratio of 3.8 (95\% CI 1.5?9.8). Poor source water quality, as indicated by Escherichia coli counts of 10 or more cfu 100 ml21, increased risk by 2.9 (1.5?5.7). There were no other significant risk factors for dysentery and none for watery diarrhoea. In this study, endemic dysentery is associated only with faecal contamination of source water. Sources other than standpipes, including improved groundwater, are of greater risk. Remediation of water quality by treatment at source or in the household will be required to achieve access to safe drinking water in accordance with the 7th Millennium Development Goal.} } @article{soton154465, volume = {30}, number = {9}, month = {May}, author = {Ivan Haigh and Robert Nicholls and Neil Wells}, title = {Assessing changes in extreme sea levels: Application to the English Channel, 1900?2006}, journal = {Continental Shelf Research}, pages = {1042--1055}, year = {2010}, keywords = {Astronomical tides, Mean sea level, Storm surges, Climate changes, Extremes, North Atlantic Oscillation, English Channel, Southern England, Northern France}, url = {https://eprints.soton.ac.uk/154465/}, abstract = {A recently extended and spatially rich English Channel sea level dataset has been used to evaluate changes in extreme still water levels throughout the 20th century. Sea level records from 18 tide gauges have been rigorously checked for errors and split into mean sea level, tidal and non-tidal components. These components and the interaction between surge and tide have been analysed separately for significant trends before determining changes in extreme sea level. Mean sea level is rising at 0.8?2.3 mm/year, depending on location. There is a small increase (0.1?0.3 mm/year) in the annual mean high water of astronomical tidal origin, relative to mean sea level, and an increase (0.2?0.6 mm/year) in annual mean tidal range. There is considerable intra- and inter-decadal variability in surge intensity with the strongest intensity in the late 1950s. Storm surges show a statistically significant weak negative correlation to the winter North Atlantic Oscillation index throughout the Channel and a stronger significant positive correlation at the boundary with the southern North Sea. Tide?surge interactions increase eastward along the English Channel, but no significant long-term changes in the distribution of tide?surge interaction are evident. In conclusion, extreme sea levels increased at all of the 18 sites, but at rates not statistically different from that observed in mean sea level.} } @article{soton375537, volume = {177}, number = {1}, month = {December}, author = {Ed C. Hathorne and Torben Stichel and Bastian Br{\"u}ck and Martin Frank}, title = {Rare earth element distribution in the Atlantic sector of the Southern Ocean: The balance between particle scavenging and vertical supply}, journal = {Marine Chemistry}, pages = {157--171}, year = {2015}, keywords = {Rare earth elements, Atlantic sector of the Southern Ocean, Weddell Gyre, GEOTRACES}, url = {https://eprints.soton.ac.uk/375537/}, abstract = {{\ensuremath{<}}br/{\ensuremath{>}}The concentrations of rare earth elements (REEs) in seawater display systematic variations related to weathering inputs, particle scavenging and water mass histories. Here we investigate the REE concentrations of water column profiles in the Atlantic sector of the Southern Ocean, a key region of the global circulation and primary production. The data reveal a pronounced contrast between the vertical profiles in the Antarctic Circumpolar Current (ACC) and those south of the ACC in the Weddell Gyre (WG). The ACC profiles exhibit the typical increase of REE concentrations with water depth and a change in the shape of the profiles from near linear for the light REEs to more convex for the heavy REEs. In contrast, the WG profiles exhibit high REE concentrations throughout the water column with only the near surface samples showing slightly reduced concentrations indicative of particle scavenging. Seawater normalised REE patterns reveal the strong remineralisation signal in the ACC with the light REEs preferentially removed in surface waters and the mirror image pattern of their preferential release in deep waters. In the WG the patterns are relatively homogenous reflecting the prevalence of well-mixed Lower Circumpolar Deep Water (LCDW) that follows shoaling isopycnals in the region. In the WG particle scavenging of REEs is comparatively small and limited to the summer months by light limitation and winter sea ice cover. Considering the surface water depletion compared to LCDW and that the surface waters of the WG are replaced every few years, the removal rate is estimated to be on the order of 1 nmol m? 3 yr? 1 for La and Nd. The negative cerium anomalies observed in deep waters are some of the strongest found globally with only the deepest waters in parts of the Pacific having stronger anomalies. These deep waters have been isolated from fresh continental REE inputs during their long journey through the abyssal Indo-Pacific Ocean, which suggests that the high REE concentrations found in the ACC and WG reflect contributions from old deep waters.{\ensuremath{<}}br/{\ensuremath{>}}} } @techreport{soton15510, type = {Project Report}, title = {RRS James Clark Ross Cruise 94, 01 Dec-15 Dec 2003. Drake Passage repeat hydrography: WOCE Southern Repeat Section 1b - Burdwood Bank to Elephant Island}, author = {E.J. Hawker and B.A. King and M. Sparrow}, publisher = {Southampton Oceanography Centre, University of Southampton}, year = {2005}, series = {55}, keywords = {Antarctic Circumpolar Current, Antarctic Ocean, ADCP, Acoustic Doppler Current Profiler, cruise 94 2003, CTD Observations, Drake Passage, James Clark Ross, Lowered ADCP, LADCP, Southern Ocean, Vessel-Mounted ADCP, WOCE, World Ocean Circulation Experiment}, url = {https://eprints.soton.ac.uk/15510/}, abstract = {This report describes the ninth occupation of the Drake Passage section, established during the World Ocean Circulation Experiment as repeat section SR1b. It was first occupied by Southampton Oceanography Centre in collaboration with the British Antarctic Survey in 1993, and has been re-occupied most years. Thirty-two full depth stations were completed, a test station, the RaTS station in Marguarite Bay, and the 30 stations for the SR1b Drake Passage section. The CTD was a Sea-Bird 911plus with dual temperature and conductivity sensors, an altimeter{\ensuremath{<}}br/{\ensuremath{>}}and an SBE35 thermometer. Direct velocity (LADCP) measurements were also made, using a downward looking RDI Workhorse WH300 ADCP (WH) unit. Various underway measurements included navigation, VM-ADCP, sea surface temperature and salinity, water depth and meteorological parameters.} } @article{soton341923, volume = {65}, month = {July}, title = {Signature of organic matter exported from naturally Fe-fertilised oceanic waters}, author = {Maria T. Hernandez-Sanchez and Jens Holtvoeth and Rachel A. Mills and Elizabeth H. Fisher and George A. Wolff and Richard D. Pancost}, year = {2012}, pages = {59--72}, journal = {Deep Sea Research Part I: Oceanographic Research Papers}, keywords = {Palaeoproducvity proxies, Biomarkers, Degradation, Southern Ocean}, url = {https://eprints.soton.ac.uk/341923/}, abstract = {Biomarker distributions and organic carbon and nitrogen isotopic signatures of organic matter (OM) produced in surface waters around the Crozet Plateau (Southern Ocean) are significantly different between a Fe-fertilised region (north) and a high nutrient low chlorophyll region (HNLC, south). If these OM signatures are exported to and preserved in surface sediments, they could potentially be used as palaeo-proxies for identifying Fe-fertilisation events in the past. Here, we assess the alteration of the OM signature through the water column and at the sediment?water interface by comparing organic signatures in surface waters, sediment traps and surface sediments. Our results suggest that there is significant degradation of OM during transport to the sea floor, which causes reduced fluxes of biomarkers to sediments north and east of the Crozet Plateau. Sterols, alkenones and C27 and C29 12-hydroxymethyl alkanoates, and C28 1,14-diols appear to be less labile than total organic carbon (TOC), except to the north, where alkenones and sterols are more rapidly degraded than TOC. Sedimentary bulk and compound specific ?13C values also reflect surface water productivity patterns, with elevated values occurring in sediments underlying the Fe-fertilised waters. In contrast, ?15N values appear to be strongly biased by degradation and grazing during export and burial. Thus, only some of the differences observed in surface waters between the Fe- fertilised and HNLC areas are exported to deep waters and preserved in the sedimentary record, suggesting that caution is required in the application of these proxies to studies of ocean palaeoproductivity.} } @article{soton210493, volume = {59-60}, month = {January}, title = {Responses of microplankton community structure to iron addition in the Scotia Sea}, author = {D.J. Hinz and M.C. Nielsd{\'o}ttir and R.E. Korb and M.J. Whitehouse and A.J. Poulton and C.M. Moore and E.P. Achterberg and T.S. Bibby}, year = {2012}, pages = {36--46}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Phytoplankton, Diatoms, Limiting factors, Physiology, Southern Ocean, Scotia Sea}, url = {https://eprints.soton.ac.uk/210493/}, abstract = {The Southern Ocean is largely a High Nutrient Low Chlorophyll (HNLC) region where macronutrient concentrations are high and phytoplankton productivity is low. However, there are productive ?hot spots? that sustain large phytoplankton blooms. These areas, maintained by natural iron (Fe) fertilization, are important for the Southern Ocean ecosystem and for driving carbon export. Fe addition on-deck bioassay experiments were conducted on two cruises to the Scotia Sea region of the Southern Ocean (austral spring 2006 and summer 2008) to better understand how Fe controls the microplankton (20?200 ?m) community structure on a seasonal basis. Light microscopy and fast-repetition rate fluorometry were used to examine changes in the species composition and physiological status of the microplankton community. Bioassays were carried out in three contrasting regions of the Scotia Sea: (1) a naturally Fe-fertilized, high chlorophyll area downstream (north and northwest) of the Islands of South Georgia (DSG); (2) a low Fe, low chlorophyll area upstream (south) of the Islands of South Georgia (USG); and (3) a naturally Fe-fertilized area north of the South Orkney Islands (SOI). Multivariate statistics were applied to the light microscopy results, showing significant differences between the initial microplankton communities for each of the bioassays. These differences were primarily spatial (between regions) and secondarily temporal (between seasons). Significant microplankton community shifts occurred in three of five bioassays, those in spring and summer USG and in summer DSG only. In summer, USG community responses increased significantly in medium (100?1000 pg C cell?1) and large (\>1000 pg C cell?1) diatom species in response to Fe addition. Such a response was consistent with relief from in situ Fe limitation, which favours larger microplankton species with higher Fe requirements and subject to lower grazing pressures. The largest biomass increase in Fe-treated bioassay bottles was in Pseudonitzschia spp., which suggests that this genus may be a particularly important member of the microplankton community in the Scotia Sea.} } @article{soton210497, volume = {59-60}, month = {January}, title = {Comparative seasonal biogeography of mineralising nannoplankton in the Scotia Sea: Emiliania huxleyi, Fragilariopsis spp. and Tetraparma pelagica}, author = {D.J. Hinz and A.J. Poulton and M.C. Nielsd{\'o}ttir and S. Steigenberger and R.E. Korb and E.P. Achterberg and T.S. Bibby}, year = {2012}, pages = {57--66}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Southern Ocean, Scotia Sea, Diatoms, Nannoplankton, Biogeography, Coccolithophores}, url = {https://eprints.soton.ac.uk/210497/}, abstract = {The Southern Ocean is an important biogeochemical region on a global scale, in which mineralising phytoplankton play a role in cycling energy, carbon and nutrients. Mineralising phytoplankton with cells 2?20 ?m in diameter (nannoplankton) are poorly enumerated by traditional preservation and microscopy techniques, yet may fulfil an important role in the Southern Ocean. Here we define the spatial and temporal biogeography for these mineralising nannoplankton assessed by scanning electron microscopy in conjunction with an array of biological, physical, and chemical variables during two cruises to the Scotia Sea region of the Southern Ocean. The cruises encompassed two seasons, austral summer (January?February 2008) and austral autumn (March?April 2009).{\ensuremath{<}}br/{\ensuremath{>}}{\ensuremath{<}}br/{\ensuremath{>}}The biogeography of the three most numerous mineralising nannoplankton groups, the coccolithophore Emiliania huxleyi, the smaller (\<10 ?m) species of the diatom genus Fragilariopsis, and chrysophytes of the genus Tetraparma (mostly Tetraparma pelagica) were found to be related to the boundaries of the major circumpolar fronts. E. huxleyi abundances were relatively high in the northern water masses (maximum of 650 cells ml?1), while T. pelagica abundances were high in the southern water masses (maximum of 1910 cells ml?1). Small Fragilariopsis spp. abundances were also highest in the southern water masses (maximum of 1820 cells ml?1), but this group was present throughout the Scotia Sea.{\ensuremath{<}}br/{\ensuremath{>}}{\ensuremath{<}}br/{\ensuremath{>}}Multivariate statistical analysis found that the most influential environmental variables controlling mineralising nannoplankton biogeography were sea surface temperature and silicate concentration. Estimates of biomass indicated that the Scotia Sea mineralising nannoplankton community formed a substantial part of the total phytoplankton community, particularly south of the Southern Antarctic Circumpolar Current Front (SACCF) during the austral autumn, where mineralising nannoplankton biomass reached 36\% of the total phytoplankton biomass. The results that are obtained suggest that traditional microscopic surveys of large Southern Ocean phytoplankton may underestimate total biomass by excluding key mineralising nannoplankton groups. Greater appreciation of the ecological significance of mineralising nannoplankton in the Southern Ocean will improve our understanding of the relationships between environmental parameters, primary production, and the biological carbon pump in this ecosystem.} } @article{soton8972, volume = {20}, number = {7}, title = {Spatial and temporal patterns linking southern low and high latitudes during South Pacific warm and cold events}, author = {R.E. Houseago-Stokes and G.R. McGregor}, year = {2000}, pages = {793--801}, journal = {International Journal of Climatology}, keywords = {SOUTH PACIFIC OCEAN, TELECONNECTIONS, ENSO, EL NINO, SOUTHERN OSCILLATION, CLIMATIC CHANGE EFFECTS}, url = {https://eprints.soton.ac.uk/8972/}, abstract = {The phase and magnitude of the first harmonic of cold and warm event-centred 24-month 500 hPa height anomalies over the Southern Hemisphere are investigated in order to establish whether low and high latitude 500 hPa pressure anomalies are linked during Pacific Ocean warm (El Ni{\~n}o) and cold (La Ni{\~n}a) events. Study results revealed a linkage of pressure anomalies centred on 60?E in the Indian Ocean-East Antarctic region during cold events. In contrast to cold events, warm event signals in this area, as well as in the Antarctic Peninsula region, lack clarity because of considerable warm event variability. During warm events, however, a clear wave train of anomalies occurs along the South Pacific Convergence Zone (SPCZ). This is matched with a strong meridional contrast in the phase of 500 hPa anomalies such that low and high latitudes are out of phase with mid-latitudes. This Pacific/South American (PSA) pattern resembles the Pacific/North American (PNA) pattern, and is thought to play a major role in the transport of El Ni{\~n}o-Southern Oscillation (ENSO) signals from low to high latitudes.} } @article{soton8035, volume = {31}, number = {10}, title = {Why western boundary currents in realistic oceans are inviscid: a link between form stress and bottom pressure torques}, author = {C.W. Hughes and B.A. de Cuevas}, year = {2001}, pages = {2871--2885}, journal = {Journal of Physical Oceanography}, keywords = {WOCE, WESTERN BOUNDARY CURRENTS, BOTTOM TOPOGRAPHY, SOUTHERN OCEAN, ANTARCTIC OCEAN, SVERDRUP BALANCE, BOTTOM PRESSURE}, url = {https://eprints.soton.ac.uk/8035/}, abstract = {It is shown that wind stress curl is balanced by bottom pressure torque in a zonal integral over any strip wide enough to smooth out the effect of nonlinear terms (typically about 3? of latitude). The derivation is completely general as long as the zonal wind stress is balanced by form stress at each latitude, as is known to be the case in the ocean. This implies that viscous torques are not important in western boundary currents, their place being taken by bottom pressure torques. The prediction is confirmed in the context of a global, eddy-permitting, numerical ocean model. This link between form stress and bottom pressure torques makes it easier to consider Southern Ocean dynamics and subtropical gyre dynamics in the same conceptual framework, with topographic interactions being important in both cases.} } @article{soton347546, volume = {65}, month = {July}, title = {Combining point correlation maps with self-organising maps to compare observed and simulated atmospheric teleconnection patterns}, author = {F.K. Hunt and J.J-M. Hirschi and Bablu Sinha and Kevin Oliver and Neil Wells}, year = {2013}, pages = {20822}, journal = {Tellus A}, keywords = {teleconnections, self-organising map, climate model, North Atlantic Oscillation, El Nino Southern Oscillation, empirical orthogonal function}, url = {https://eprints.soton.ac.uk/347546/}, abstract = {We use a new method based on point correlation maps and self-organising maps (SOMs) to identify teleconnection patterns in 60 yr of National Centres for Environmental Prediction/National Centre for Atmospheric Research (NCEP/NCAR) sea level pressure (SLP) re-analysis data. The most prevalent patterns are the El Nino Southern Oscillation (ENSO), the North Atlantic Oscillation (NAO) and the Southern Annular Mode (SAM). Asymmetries are found between base points in opposite centres of action of the NAO and the Pacific North America pattern (PNA). The SOM-based method is a powerful tool that allows us to efficiently assess how realistically teleconnections are reproduced in any climate model. The degree of agreement between modelled and re-analysis-based teleconnections (or between different models) can be summarised in a single plot. Here, we illustrate this by assessing the skill of the medium complexity climate model FORTE (Fast Ocean Rapid Troposphere Experiment). FORTE reproduces some realistic teleconnections, such as the Arctic Oscillation (AO), the NAO, the PNA, the SAM, the African Monsoon and ENSO, along with several other teleconnections, which resemble to varying degrees the corresponding NCEP patterns. However, FORTE tends to underestimate the strength of the correlation patterns and the patterns tend to be slightly too zonal. The accuracy of frequency of occurrence is variable between patterns. The Indian Ocean is a region where FORTE performs poorly, as it does not reproduce the teleconnection patterns linked to the Indian Monsoon. In contrast, the North and equatorial Pacific and North Atlantic are reasonably well reproduced.} } @article{soton301344, volume = {2}, number = {2}, month = {February}, author = {Jeroen Ingels and Ann Vanreusel and Angelika Brandt and Ana I. Catarino and Bruno David and Chantal De Ridder and Philippe Dubois and Andrew J. Gooday and Patrick Martin and Francesca Pasotti and Henri Robert}, title = {Possible effects of global environmental changes on Antarctic benthos: a synthesis across five major taxa}, journal = {Ecology and Evolution}, pages = {453--485}, year = {2012}, keywords = {Amphipoda, Echinoidea, Foraminifera, global climate change, Isopoda, Nematoda, Southern Ocean, zoobenthos}, url = {https://eprints.soton.ac.uk/301344/}, abstract = {Because of the unique conditions that exist around the Antarctic continent, Southern Ocean (SO) ecosystems are very susceptible to the growing impact of global climate change and other anthropogenic influences. Consequently, there is an urgent need to understand how SO marine life will cope with expected future changes in the environment. Studies of Antarctic organisms have shown that individual species and higher taxa display different degrees of sensitivity to environmental shifts, making it difficult to predict overall community or ecosystem responses. This emphasizes the need for an improved understanding of the Antarctic benthic ecosystem response to global climate change using a multitaxon approach with consideration of different levels of biological organization. Here, we provide a synthesis of the ability of five important Antarctic benthic taxa (Foraminifera, Nematoda, Amphipoda, Isopoda, and Echinoidea) to cope with changes in the environment (temperature, pH, ice cover, ice scouring, food quantity, and quality) that are linked to climatic changes. Responses from individual to the taxon-specific community level to these drivers will vary with taxon but will include local species extinctions, invasions of warmer-water species, shifts in diversity, dominance, and trophic group composition, all with likely consequences for ecosystem functioning. Limitations in our current knowledge and understanding of climate change effects on the different levels are discussed.} } @article{soton58511, volume = {363}, number = {1826}, month = {January}, author = {J. Carter Ingram and Terence P. Dawson}, title = {Climate change impacts and vegetation response on the island of Madagascar}, journal = {Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences}, pages = {55--59}, year = {2005}, keywords = {Madagascar, vegetation change, Enso (El Ni{\~n}o Southern Oscillation), Ndvi (Normalized Difference Vegetation Index)}, url = {https://eprints.soton.ac.uk/58511/}, abstract = {The island of Madagascar has been labelled the world's number one conservation 'hot spot' because of increasing anthropogenic degradation of its natural habitats, which support a high level of species endemism. However, climatic phenomena may also have a significant impact upon the island's flora and fauna. An analysis of 18 years of monthly satellite images from the National Oceanographic and Atmospheric Administration's (NOAA) Advanced Very High Resolution Radiometer (AVHRR) have demonstrated that there is a dynamic pattern in Madagascar's vegetative cover both annually and seasonally throughout 1982-1999. Over interannual time-scales, we show that this vegetation response, calculated using the normalized difference vegetation index (NDVI), has a strong negative correlation with the El Ni{\~n}o Southern Oscillation (ENSO), which can be attributable to drought events and associated wildfires. Global climate change is predicted to increase the frequency of the ENSO phenomenon, resulting in further decline of Madagascar's natural environment.} } @article{soton44007, volume = {111}, number = {C10}, title = {A quick response of the equatorial ocean to Antarctic sea ice/salinity anomalies}, author = {V.O. Ivchenko and V.B. Zalesny and M.R. Drinkwater and J. Schroeter}, year = {2006}, pages = {C10018}, journal = {Journal of Geophysical Research}, keywords = {ocean teleconnections, rapid response, El Ni{\~n}o, Southern Ocean, Rossby wave, Kelvin wave}, url = {https://eprints.soton.ac.uk/44007/}, abstract = {The potential mechanisms for a quick response of the equatorial ocean to processes occurring in the high-latitude Southern Ocean have been investigated. In the Southern Ocean at the Drake Passage latitudes, there is an zonally unbounded ?channel?, the Antarctic Circumpolar Current Belt (ACCB). It is demonstrated that in a multiconnected domain such as the ACCB, signals generated by anomalies in the Southern Ocean sea ice cover/salinity distribution can propagate in a wave-like manner in the form of fast moving barotropic Rossby waves. A disturbance induced near the Drake Passage is demonstrated to generate a Rossby wave that propagates across the Pacific in only a few days. This signal is reflected at the western boundary of the Pacific and generates an equatorward propagating coastally trapped Kelvin wave. The resulting temperature anomaly moves northward along the western coastline up to the vicinity of the equator and increases in amplitude over time. The anomaly in the western edge of equatorial Pacific then begins to propagate eastward along the equator as a trapped equatorial wave. After about 2?3 months this wave reaches the eastern coast, reflects, and generates the coastal trapped wave, which propagates north and south along the coastline in both hemispheres. This process is suggested as one possible direct mechanism by which the extratropical ocean can induce anomalies in the equatorial ocean.} } @article{soton346413, volume = {80}, number = {2}, month = {May}, author = {Rachel E. Jamieson and Alex D. Rogers and David S.M. Billett and Dan A. Smale and David A. Pearce}, title = {Patterns of marine bacterioplankton biodiversity in the surface waters of the Scotia Arc, Southern Ocean}, journal = {FEMS Microbiology Ecology}, pages = {452--468}, year = {2012}, keywords = {bacteria, antarctic, marine, patchiness, distribution, southern ocean}, url = {https://eprints.soton.ac.uk/346413/}, abstract = {Spatial patchiness in marine surface bacterioplankton populations was investigated in the Southern Ocean, where the Antarctic Circumpolar Current meets the islands of the Scotia Arc and is subjected to terrestrial input, upwelling of nutrients and seasonal phytoplankton blooms. Total bacterioplankton population density, group-specific taxonomic distribution and six of eight dominant members of the bacterioplankton community were found to be consistent across 18 nearshore sites at eight locations around the Scotia Arc. Results from seven independent 16S rRNA gene clone libraries (1223 sequences in total) and fluorescent in situ hybridization suggested that microbial assemblages were predominantly homogeneous between Scotia Arc sites, where the Alphaproteobacteria, Gammaproteobacteria and the Cytophaga?Flavobacterium?Bacteroidetes cluster were the dominant bacterial groups. Of the 1223 useable sequences generated, 1087 (89\%) shared ? 97\% similarity with marine microorganisms and 331 (27\%) matched published sequences previously detected in permanently cold Arctic and Antarctic marine environments. Taken together, results suggest that the dominant bacterioplankton groups are consistent between locations, but significant differences may be detected across the rare biodiversity.} } @article{soton432713, month = {June}, title = {Fe sources and transport from the Antarctic Peninsula shelf to the southern Scotia Sea}, author = {Mingshun Jiang and Christopher I. Measures and Katherine A. Barbeau and Matthew A. Charette and Sarah T. Gille and Mariko Hatta and Mati Kahru and B. Gregory Mitchell and Alberto C. Naveira Garabato and Christian Reiss and Karen Selph and Meng Zhou}, year = {2019}, journal = {Deep-Sea Research Part I: Oceanographic Research Papers}, keywords = {Antarctic Peninsula, Coupled physical-biogeochemical model, Iron (Fe), Off-shelf transport, Shelf sediment, Southern Scotia Sea}, url = {https://eprints.soton.ac.uk/432713/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}The Antarctic Peninsula (AP) shelf is an important source of dissolved iron (Fe) to the upper ocean in the southern Scotia Sea, one of the most productive regions of the Southern Ocean. Here we present results from a four-year (2003-2006) numerical simulation using a regional coupled physical-biogeochemical model to assess the Fe sources and transport on the AP shelf and toward the southern Scotia Sea. The model was validated with a suite of data derived from in situ surveys and remote sensing. Model results indicate that sediments in the AP shelf and the South Orkney Plateau (SOP) provide the dominant source of Fe to the upper 500 m in the southern Scotia Sea. Additional Fe inputs to the region are associated with the Antarctic Circumpolar Current (ACC) and the northern limb of the Weddell Gyre, deep-ocean sediment sources, dust deposition, and icebergs. Fe on the AP shelf originates primarily from sediments on the relatively shallow inner shelf and is directly injected into the water column and subsequently transported toward Elephant Island by the confluent shelf currents. Off-shelf Fe export is primarily through entrainment of shelf waters by the ACC's Southern Boundary frontal jet along the northern edge of the AP shelf, the Hesperides Trough, and the SOP shelf. About 70\% of the off-shelf export takes place below the surface mixed layer, and is subsequently re-supplied to the euphotic zone through vertical mixing, mainly during austral fall and winter. The exported shelf-derived Fe is then advected downstream by the ACC and Weddell Gyre and spread over the southern and eastern Scotia Seas. Taken together, shelf Fe export witin top 500 m meets nearly all of the Fe demand of phytoplankton photosynthesis in the southern Scotia Sea. Waters with elevated Fe concentrations in the Scotia Sea are largely restricted to south of the Southern ACC Front.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton364845, volume = {119}, number = {6}, month = {June}, author = {Lo{\"i}c Jullion and Alberto C. Naveira Garabato and Sheldon Bacon and Michael P. Meredith and Pete J. Brown and Sinhu{\'e} Torres-Vald{\'e}s and Kevin G. Speer and Paul R. Holland and Jun Dong and Doroth{\'e}e Bakker and Mario Hoppema and Brice Loose and Hugh J. Venables and William J. Jenkins and Marie-Jos{\'e} Messias and Eberhard Fahrbach}, title = {The contribution of the Weddell Gyre to the lower limb of the global overturning circulation}, journal = {Journal of Geophysical Research: Oceans}, pages = {3357--3377}, year = {2014}, keywords = {Weddell Sea, Southern Ocean, meridional overturning circulation, oceanography, sea ice, climate}, url = {https://eprints.soton.ac.uk/364845/}, abstract = {The horizontal and vertical circulation of the Weddell Gyre is diagnosed using a box inverse model constructed with recent hydrographic sections and including mobile sea ice and eddy transports. The gyre is found to convey 42 {$\pm$} 8 Sv (1 Sv = 106 m3 s-1) across the central Weddell Sea and to intensify to 54{$\pm$}15 Sv further offshore. This circulation injects 36{$\pm$}13 TW of heat from the Antarctic Circumpolar Current to the gyre, and exports 51 {$\pm$} 23 mSv of freshwater, including 13 {$\pm$} 1 mSv as sea ice to the mid-latitude Southern Ocean. The gyre's overturning circulation has an asymmetric double-cell structure, in which 13 {$\pm$} 4 Sv of Circumpolar Deep Water (CDW) and relatively light Antarctic Bottom Water (AABW) are transformed into upper-ocean water masses by mid-gyre upwelling (at a rate of 2 {$\pm$} 2 Sv) and into denser AABW by downwelling focussed at the western boundary (8 {$\pm$} 2 Sv). The gyre circulation exhibits a substantial throughflow component, by which CDW and AABW enter the gyre from the Indian sector, undergo ventilation and densification within the gyre, and are exported to the South Atlantic across the gyre's northern rim. The relatively modest net production of AABW in the Weddell Gyre (6{$\pm$}2 Sv) suggests that the gyre's prominence in the closure of the lower limb of global oceanic overturning stems largely from the recycling and equatorward export of Indian-sourced AABW.} } @article{soton354485, volume = {26}, number = {20}, month = {October}, author = {Lo{\"i}c Jullion and Alberto C. Naveira Garabato and Michael P. Meredith and Paul R. Holland and Peggy Courtois and Brian A. King}, title = {Decadal freshening of the Antarctic Bottom Water exported from the Weddell Sea}, journal = {Journal of Climate}, pages = {8111--8125}, year = {2013}, keywords = {South Atlantic Ocean, Southern Ocean, Ocean circulation, Abyssal circulation, Bottom currents/bottom water, Trends}, url = {https://eprints.soton.ac.uk/354485/}, abstract = {Recent decadal changes in Southern Hemisphere climate have driven strong responses from the cryosphere. Concurrently, there has been a marked freshening of the shelf and bottom waters across a wide sector of the Southern Ocean, hypothesised to be caused by accelerated glacial melt in response to a greater flux of warm waters from the Antarctic Circumpolar Current onto the shelves of West Antarctica. However, the circumpolar pattern of changes has been incomplete: no decadal freshening in the deep layers of the Atlantic sector had been observed. In this study, we document a significant freshening of the Antarctic Bottom Water exported from the Weddell Sea, which is the source for the abyssal layer of the Atlantic overturning circulation, and we trace its possible origin to atmospheric-forced changes in the ice shelves and sea ice on the eastern flank of the Antarctic Peninsula that include an anthropogenic component. These findings suggest that the expansive and relatively cool Weddell gyre does not insulate the bottom water formation regions in the Atlantic sector from the ongoing changes in climatic forcing over the Antarctic region.} } @article{soton59901, volume = {107}, number = {2}, title = {Cytogenetic and molecular monitoring of residual disease in chronic myeloid leukaemia}, author = {J. Kaeda and A. Chase and J.M. Goldman}, year = {2002}, pages = {64--75}, journal = {Acta Haematologica}, keywords = {neoplasm proteins, stem cell transplantation, interferon-alpha, methods, review, rna, standards, therapy, bone, proteins, southern, london, western, neoplasm, bone marrow, residual, pathology, humans, cytogenetic analysis, polymerase chain reaction, protein, myeloid, analysis, cell transplantation, leukemia, fluorescence, transplantation, blotting, metaphase, diagnosis, tyrosine, chronic, patients, disease, reverse transcriptase polymerase chain reaction, genetics}, url = {https://eprints.soton.ac.uk/59901/}, abstract = {For patients with chronic myeloid leukaemia, methods for monitoring response to treatment have changed considerably in recent years. In the 1980s, the principal approach was repeated examination of bone marrow metaphases for the presence of the Ph chromosome in patients treated by interferon-alpha (IFN-alpha) or allogeneic stem cell transplantation. The use of fluorescence in situ hybridisation (FISH) techniques to detect the BCR-ABL fusion gene in Ph-positive leukaemia cells increased the sensitivity of cytogenetic studies to some degree. In the last 10 years, the reverse-transcriptase polymerase chain reaction (RT-PCR) has proved extremely valuable for assessing and monitoring minimal residual disease in patients who achieve Ph negativity after treatment with IFN-alpha or with the new Abl tyrosine kinase inhibitor imatinib mesylate or after allogeneic stem cell transplantation (SCT). Results are consistent with the notion that the majority of long-term survivors after allogeneic SCT are probably 'cured'; for other patients monitored serially in complete cytogenetic remission, rising numbers of BCR-ABL transcripts detected by RT-PCR can indicate the need for further therapy} } @article{soton468931, volume = {91}, number = {3}, month = {March}, author = {A Kampk{\"o}tter and I Ridgers and D A Johnston and D Rollinson and W Kunz and C G Grevelding}, title = {Schistosoma mansoni: cloning and characterization of the Ras homologue}, journal = {Experimental Parasitology}, pages = {280--3}, year = {1999}, keywords = {Amino Acid Sequence, Animals, Blotting, Southern, Cloning, Molecular, DNA, Helminth/analysis, Female, Humans, Male, Molecular Sequence Data, Schistosoma mansoni/chemistry, ras Proteins/chemistry}, url = {https://eprints.soton.ac.uk/468931/}, abstract = {In an attempt to identify and characterize molecules throught likely to play important roles during the development of schistosomes, we started to search for signal transductionmolecules in Schistosoma mansoni{\ensuremath{<}}br/{\ensuremath{>}}} } @article{soton477624, volume = {128}, number = {3}, month = {March}, author = {A. Klocker and A. C. Naveira Garabato and F. Roquet and C. De Lavergne and S. R. Rintoul}, note = {Funding Information: The authors thank the Consortium for Ocean?Sea Ice Modeling in Australia (COSIMA; www.cosima.org.au ) for making the ACCESS?OM2 suite of models available at github.com/COSIMA/access-om2 . Model runs were undertaken with the assistance of resources from the National Computational Infrastructure (NCI), which is supported by the Australian Government. This research was supported under Australian Research Council's Special Research Initiative for Antarctic Gateway Partnership (Project ID SR140300001). This project received grant funding from the Australian Government as part of the Antarctic Science Collaboration Initiative program. The work was supported in part by the Centre for Southern Hemisphere Oceans Research, a partnership between CSIRO, the Qingdao National Laboratory for Marine Science and Technology, the University of New South Wales and the University of Tasmania and by the Australian Antarctic Program Partnership. Publisher Copyright: {\copyright} 2023. American Geophysical Union. All Rights Reserved.}, title = {Generation of the internal pycnocline in the subpolar southern ocean by wintertime sea ice melting}, journal = {Journal of Geophysical Research: Oceans}, year = {2023}, keywords = {Southern Ocean, ice-ocean interaction, pycnocline, sea ice}, url = {https://eprints.soton.ac.uk/477624/}, abstract = {The ocean's internal pycnocline is a layer of elevated stratification that separates the well-ventilated upper ocean from the more slowly renewed deep ocean. Despite its pivotal role in organizing ocean circulation, the processes governing the formation of the internal pycnocline remain little understood. Classical theories on pycnocline formation have been couched in terms of temperature and it is not clear how the theory applies in the high-latitude Southern Ocean, where stratification is dominated by salinity. Here we assess the mechanisms generating the internal pycnocline at southern high latitudes through the analysis of a high-resolution, realistic, global sea ice?ocean model. We show evidence suggesting that the internal pycnocline's formation is associated with sea ice-ocean interactions in two distinct ice-covered regions, fringing the Antarctic continental slope and the winter sea-ice edge. In both areas, winter-persistent sea-ice melt creates strong, salinity-based stratification at the base of the winter mixed layer. The resulting sheets of high stratification subsequently descend into the ocean interior at fronts of the Antarctic Circumpolar Current, and connect seamlessly to the internal pycnocline in areas further north in which pycnocline stratification is determined by temperature. Our findings thus suggest an important role of localized sea ice-ocean interactions in configuring the vertical structure of the Southern Ocean.} } @article{soton174077, volume = {38}, title = {Mechanisms controlling warm water volume interannual variations in the Equatorial Pacific: Diabatic versus adiabatic processes}, author = {M. Lengaigne and U. Hausmann and G. Madec and C.E. Menkes and J. Vialard and J.M. Molines}, year = {2012}, pages = {1031--1046}, journal = {Climate Dynamics}, keywords = {El Nin?o/Southern Oscillation ? Warm water volume ? Equatorial Pacific ? Western boundary currents ? Solar penetration ? Vertical mixing}, url = {https://eprints.soton.ac.uk/174077/}, abstract = {Variations of the volume of warm water above the thermocline in the equatorial Pacific are a good predictor of ENSO (El Nin?o/Southern Oscillation) and are thought to be critical for its preconditioning and development. In this study, the Warm Water Volume (WWV) interannual variability is analysed using forced general circulation model experiments and an original method for diagnosing processes responsible for WWV variations. The meridional recharge/discharge to higher latitudes drives 60\% of the ENSO-related equatorial WWV variations, while diabatic processes in the eastern equatorial Pacific account for the remaining 40\%. Interior meridional transport is partially compensated by western boundary transports, especially in the southern hemisphere. Diabatic equatorial WWV formation (depletions) during La Nina (El Nino) are explained by enhanced (reduced) diathermal transport through enhanced (reduced) vertical mixing and penetrating solar forcing at the 20?C isotherm depth. The respective contribution of diabatic and adiabatic processes during build-ups/depletions strongly varies from event-toevent.{\ensuremath{<}}br/{\ensuremath{>}}The WWV build-up during neutral ENSO phases (e.g. 1980?1982) is almost entirely controlled by meridional recharge, providing a text-book example for the recharge/discharge oscillator?s theory. On the other hand, diabatic processes are particularly active during the strongest La Nina events (1984, 1988, 1999), contributing to more than 70\% of the WWV build-up, with heating by penetrative solar fluxes explaining as much as 30\% of the total build-up due to a very shallow thermocline in the eastern Pacific. This study does not invalidate the recharge/discharge oscillator theory but rather emphasizes the importance of equatorial diabatic processes and western boundary transports in controlling WWV changes.} } @article{soton363156, volume = {104}, month = {June}, title = {Submarine canyons of north-western Sicily (Southern Tyrrhenian Sea): Variability in morphology, sedimentary processes and evolution on a tectonically active margin}, author = {Claudio Lo Iacono and Attilio Sulli and Mauro Agate}, year = {2014}, pages = {93--105}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Submarine canyons, Tectonics, Landslides, Swath-bathymetry, Seismic data, Sicily, Southern Tyrrhenian Sea}, url = {https://eprints.soton.ac.uk/363156/}, abstract = {Swath-bathymetry, mono-channel and multi-channel seismic reflection records acquired during the last two decades on the northern Sicilian margin have unveiled a dense network of submarine canyons within the depth range of 80?2100 m. The canyons display a relevant variability in their geometry, morphology and sedimentary processes. The margin shows a young, tectonically active shelf to slope setting, linking the Sicilian?Maghrebian Thrust Belt to the Tyrrhenian oceanic realm, developed during the Neogene?Quaternary time span. The aim of this study is to highlight the main governing factors that contributed to the evolution and differentiation of the northern Sicilian canyons, mainly focusing on the Gulf of Palermo and on the Gulf of Castellammare. Tectonic control is more evident in the canyons of the Gulf of Palermo, with submarine landslides retrograding on a steep slope and mainly controlling their evolution. Otherwise, canyons, tributaries and gullies mapped in the Gulf of Castellammare developed on a less steep substrate and display sinuous to meandering paths, with a relevant role of coastal/shelf sedimentary inputs and downslope turbidity processes in their formation. Results suggest that, despite the geographically close proximity of the two study areas, the different structural settings of the Castellammare and Palermo Basins are mainly responsible for canyon variability. Data indicate likely on-going uplift and tilting movements along the Sicilian margin, influencing the development of the studied canyons, which have probably been more active during the Quaternary glacial maxima than they are in the present day.} } @article{soton49515, volume = {54}, number = {18-20}, title = {Nitrogen uptake responses to a naturally Fe-fertilised phytoplankton bloom during the 2004/2005 CROZEX study}, author = {M.I. Lucas and S. Seeyave and R. Sanders and C.M. Moore and R. Williamson and M. Stinchcombe}, year = {2007}, pages = {2138--2173}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Natural iron fertilisation, Southern Ocean, 15N uptake, Phytoplankton communities, Phaeocystis, Carbon export}, url = {https://eprints.soton.ac.uk/49515/}, abstract = {Annual phytoplankton blooms are observed around most sub-Antarctic islands during austral spring and summer, but are absent in the surrounding high-nutrient low-chlorophyll (HNLC) ocean. The CROZEX study (2004/2005) tested the hypothesis that annual blooms occurring immediately north of the Crozet islands in the Polar Frontal Zone (PFZ) develop because of natural iron fertilisation, while to their south in HNLC waters, there is insufficient iron (Fe) to promote blooms. Size-fractionated nitrogen uptake (?N) experiments using 15N-NO3?, NH4+ and urea addressed three major goals. Firstly, measurements of NO3? uptake (?NO3?) aimed to establish whether ?NO3? responds to natural Fe fertilisation. Secondly, we compared regional ?NO3? rates, hypothesising that in Fe-fertilised regions, ?NO3? should exceed that in HNLC regions. Thirdly, by using satellite imagery, we extrapolated ?NO3? measurements made during a declining bloom to reconstruct seasonal ?NO3? by the spring bloom. Finally, we estimated the ?new? Fe demand required to support ?NO3?, comparing this with estimated Fe fluxes.{\ensuremath{<}}br/{\ensuremath{>}}Diatoms and colonial Phaeocystis dominated phytoplankton communities north of the islands, while to the south, Phaeocystis was absent. Total ?N was elevated north of the islands (400 ?mol m?2 d?1) relative to south of the islands (250 ?mol m?2 d?1). Nitrate uptake showed a clear response to Fe fertilisation, exhibiting a strong north (198 ?mol m?2 d?1) to south (74 ?mol m?2 d?1) gradient, while neither ?NH4+ nor ?urea showed such significant latitudinal gradients. The N?S integrated f-ratio gradient was 0.47?0.28 while specific N uptake (VNO3 d?1) rates were significantly higher in the Fe-fertilised region relative to those in the southern HNLC region. The potential for NH4+ inhibition of ?NO3? did not appear to be significant. High PON:chl-a ratios combined with relatively low 14C:15N uptake ratios suggested that most phytoplankton were relatively chlorotic and carbon stressed, with the exception of those growing actively within a cyclonic eddy where neither Fe nor light appeared to be limiting. Size-fractionated ?NO3? and f-ratios exhibited a complex response to NH4+ and Fe availability, with f-ratios in the \>20-?m fraction being low (0.3) in the HNLC region, but significantly higher (0.7) in a localised diatom-dominated bloom in the northern Fe-fertilised region. In contrast, f-ratios in the \<2-?m size class were similar everywhere (0.44), indicative of Fe-limitation for large-celled diatoms in the southern HNLC region. As a result of Fe-regulated ?NO3?, new production showed a N?S gradient of 24 to 15 mmol C m?2 d?1, very similar to carbon export determined from NO3? ?draw-down? and from 234Th measurements. The estimated DFe demand required to support seasonal ?NO3? in the northern region, based on conservative cellular Fe:N quotas, required surface (to 100 m) pre spring-bloom DFe concentrations of 0.75 nmol l?1. Our results support the hypothesis that phytoplankton blooms north of the islands are stimulated by natural Fe fertilisation, with a direct impact on ?NO3?, particularly for larger cells, resulting in higher new production rates relative to those from the Fe-limited HNLC region south of the Crozet islands.} } @article{soton148813, volume = {292}, number = {1-2}, month = {June}, author = {Valeria Luciani and Luca Giusberti and Claudia Agnini and Eliana Fornaciari and Domenico Rio and David J.A. Spofforth and Heiko P{\"a}like}, title = {Ecological and evolutionary response of Tethyan planktonic foraminifera to the middle Eocene climatic optimum (MECO) from the Alano section (NE Italy)}, journal = {Palaeogeography, Palaeoclimatology, Palaeoecology}, pages = {82--95}, year = {2010}, keywords = {middle eocene climatic optimum, planktonic foraminifera, paleoecology, evolution, southern alps, italy}, url = {https://eprints.soton.ac.uk/148813/}, abstract = {The enigmatic middle Eocene climatic optimum (MECO) is a transient ({\texttt{\char126}}500kyr) warming event that significantly interrupted at {\texttt{\char126}}40 Ma the long-term cooling through the middle and late Eocene, eventually resulting in establishment of permanent Antarctic ice-sheet. This event is still poorly known and data on the biotic response are so far scarce. Here we present a detailed planktonic foraminiferal analysis of the MECO interval from a marginal basin of the central-western Tethys (Alano section, northeastern Italy). The expanded and continuous Alano section provides an excellent record of this event and offers an appealing opportunity to better understand the role of climate upon calcareous plankton evolution. A sapropel-like interval, characterized by excursions in both the carbon and oxygen bulk-carbonate isotope records, represents the lithological expression of the post-MECO event in the study area and follows the {\ensuremath{\delta}}{\ensuremath{<}}sup{\ensuremath{>}}18{\ensuremath{<}}/sup{\ensuremath{>}}O negative shift, interpreted as representing the MECO warming.{\ensuremath{<}}br/{\ensuremath{>}}High-resolution quantitative analysis performed on both \>38 {\ensuremath{\mu}}m and \>63 {\ensuremath{\mu}}m fractions reveals pronounced and complex changes in planktonic foraminiferal assemblages indicating a strong environmental perturbation that parallels the variations of the stable isotope curves corresponding to the MECO and post-MECO intervals. These changes consist primarily in a marked increase in abundance of the relatively eutrophic subbotinids and of the small, low-oxygen tolerant Streptochilus, Chiloguembelina and Pseudohas-tigerina. At the same time, the arrival of the abundant opportunist eutrophic Jenkinsina and Pseudoglobigerinella bolivariana, typical species of very high-productivity areas, also occurs. The pronounced shift from oligotrophic to more eutrophic, opportunist, low-oxygen tolerant planktonic foraminiferal assemblages suggests increased nutrient input and surface ocean productivity in response to the environmental perturbation associated with the MECO. Particularly critical environmental conditions have been reached during the deposition of the sapropel-like beds as testified by the presence of common giant and/or odd morphotypes. This is interpreted as evidence of transient alteration in the ocean chemistry.{\ensuremath{<}}br/{\ensuremath{>}}The enhanced surface water productivity inferred by planktonic foraminiferal assemblages at the onset of the event should have resulted in heavier {\ensuremath{\delta}}{\ensuremath{<}}sup{\ensuremath{>}}13{\ensuremath{<}}/sup{\ensuremath{>}}C values. The recorded lightening of the carbon stable isotope preceding the maximum warmth therefore represents a robust indication that it derives principally by a conspicuous increase of pCO2. The increased productivity of surface waters, also supported by geochemical data, may have acted as mechanism for pCO2 reduction and returned the climate system to the general Eocene cooling trend. The oxygen-depleted deep waters and the organic carbon burial following the peak of the MECO event represent the local response to the MECO warming and suggest that high sequestration of organic matter, if representing a widespread response to this event, might have contributed to the decrease of pCO2 as well. Though the true mechanisms are still obscure, several lines of evidence indicate a potential pressure on planktonic foraminiferal evolution during the MECO event including permanent changes besides transient and ecologically controlled variations.} } @article{soton49759, volume = {35}, number = {8}, month = {August}, author = {M. Lyle and S. Gibbs and T.C. Moore and D.K. Rea}, title = {Late Oligocene initiation of the Antarctic Circumpolar Current: evidence from the South Pacific}, journal = {Geology}, pages = {691--694}, year = {2007}, keywords = {paleoceanography, marine geology, Cenozoic, Antarctic Circumpolar Current, Southern Ocean, Pacific Ocean}, url = {https://eprints.soton.ac.uk/49759/}, abstract = {The Antarctic Circumpolar Current (ACC) is a key feature of the Southern Ocean. Its development may have helped cool Antarctica and initiate Southern Hemisphere glaciation. The deep circulation of the ACC must have been established after both the Tasman gateway (between Antarctica and Australia) and the Drake Passage (between South America and Antarctica) opened. However, estimates for ACC initiation range over 20 m.y., from the middle Eocene to early Miocene. A new piston core of upper Oligocene to Holocene sediments from the South Pacific has allowed us to delimit the formation of the ACC to the late Oligocene (ca. 25?23 Ma). Upper Oligocene, current-worked sediments and a hiatus to the upper Miocene result from the beginning of the modern ACC flow; i.e., when strong currents and mixing throughout the water column were established. Previously published Nd isotope data date the first intrusion of Pacific water into the Atlantic much earlier. The discrepancy with our results can be reconciled by the different methods measuring different flow regimes. Tracer methods such as Nd are sensitive to relatively small and shallow incursions of water, whereas pelagic erosional regimes require vigorous deep flow.{\ensuremath{<}}br/{\ensuremath{>}}{\ensuremath{<}}br/{\ensuremath{>}}} } @article{soton418399, volume = {9}, number = {4}, month = {March}, author = {D.J. Mackay and A.J. Mungall and C Polychronakos and R Siebert and J.P. Shield and I.K. Temple and D.O. Robinson}, title = {An imprinted locus associated with transient neonatal diabetes mellitus}, journal = {Human Molecular Genetics}, pages = {589--96}, year = {2000}, keywords = {Blotting, Southern, Chromosomes, Human, Pair 6, CpG Islands, DNA Methylation, Diabetes Mellitus, Expressed Sequence Tags, Fathers, Female, Gene Dosage, Gene Duplication, Genomic Imprinting, Humans, Infant, Newborn, Male, Mothers, Polymerase Chain Reaction, Restriction Mapping, Sequence Tagged Sites, Journal Article, Research Support, Non-U.S. Gov't}, url = {https://eprints.soton.ac.uk/418399/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Recently, we reported the localization of a gene for transient neonatal diabetes mellitus (TNDM), a rare form of childhood diabetes, to an approximately 5.4 Mb region of chromosome 6q24. We have also shown that TNDM is associated with both paternal uniparental disomy (UPD) of chromosome 6 and paternal duplications of the critical region. The sequencing of P1-derived artificial chromosome clones from within the region of interest has allowed us to further localize the gene and to investigate the methylation status of the region. The gene is now known to reside in a 300-400 kb region of 6q24 which contains several CpG islands. At one island we have demonstrated differential DNA methylation between patients with paternal UPD of chromosome 6 and normal controls. In addition, two patients with TNDM, in whom neither paternal UPD of chromosome 6 nor duplication of 6q24 have been found, show a DNA methylation pattern identical to that of patients with paternal UPD of chromosome 6. Control individuals show a hemizygous methylation pattern. These results show that TNDM can be associated with a methylation change and identify a novel methylation imprint on chromosome 6 associated with TNDM.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton339896, volume = {7}, number = {4}, title = {The untold story: the regulation of police labour rights and the quest for police democratisation}, author = {Monique Marks and Jenny Fleming}, year = {2006}, pages = {309--322}, journal = {Police Practice and Research: An International Journal}, keywords = {police, police unions, democratic policing, international labour organisation, argentina, southern africa}, url = {https://eprints.soton.ac.uk/339896/}, abstract = {This paper explores the struggles for labour and social rights on the part of police officers in democratising countries. The paper suggests that the rights of police officers and labour?management relations are important issues to be acknowledged if we are serious about deepening the democratic practices of police, particularly in democratising countries. These issues should be deliberated among policing scholars and police managers as well as important international regulatory organisations such as the ILO whose current regulatory frameworks inadvertently restrict police worker rights.{\ensuremath{<}}br/{\ensuremath{>}}} } @article{soton374229, volume = {84}, number = {4}, month = {July}, author = {Leigh Marsh and Paul Tyler and Jonathan Copley and Sven Thatje}, title = {In hot and cold water: differential life-history adaptations are key to success in contrasting thermal deep-sea environments}, journal = {Journal of Animal Ecology}, pages = {898--913}, year = {2015}, keywords = {hydrothermal vent, invertebrate reproduction, life-history biology, remotely operated vehicle, Southern Ocean, thermal adaptation}, url = {https://eprints.soton.ac.uk/374229/}, abstract = {1.Few species of reptant decapod crustaceans thrive in the cold-stenothermal waters of the Southern Ocean. However, abundant populations of a new species of anomuran crab, Kiwa tyleri, occur at hydrothermal vent fields on the East Scotia Ridge. {\ensuremath{<}}br/{\ensuremath{>}}2.As a result of local thermal conditions at the vents, these crabs are not restricted by the physiological limits that otherwise exclude reptant decapods south of the polar front. {\ensuremath{<}}br/{\ensuremath{>}}3.We reveal the adult life-history of this species by piecing together variation in microdistribution, body size-frequency, sex ratio, and ovarian and embryonic development, which indicates a pattern in the distribution of female Kiwaidae in relation to their reproductive development. {\ensuremath{<}}br/{\ensuremath{>}}4.High-density "Kiwa" assemblages observed in close proximity to sources of vent fluids are constrained by the thermal limit of elevated temperatures and the availability of resources for chemosynthetic nutrition. Although adult Kiwaidae depend on epibiotic chemosynthetic bacteria for nutrition, females move offsite after extrusion of their eggs to protect brooding embryos from the chemically harsh, thermally fluctuating vent environment. Consequently, brooding females in the periphery of the vent field are in turn restricted by low-temperature physiological boundaries of the deep-water Southern Ocean environment. Females have a high reproductive investment in few, large, yolky eggs, facilitating full lecithotrophy, with the release of larvae prolonged, and asynchronous. After embryos are released, larvae are reliant on locating isolated active areas of hydrothermal flow in order to settle and survive as chemosynthetic adults. Where the cold water restricts the ability of all adult stages to migrate over long distances, these low temperatures may facilitate the larvae in the location of vent sites by extending the larval development period through hypometabolism.{\ensuremath{<}}br/{\ensuremath{>}}5.These differential life-history adaptations to contrasting thermal environments lead to a disjunct life history among males and females of Kiwa tyleri, which is key to their success in the Southern Ocean vent environment.{\ensuremath{<}}br/{\ensuremath{>}}6.We highlight the complexity in understanding the importance of life-history biology, in combination with environmental, ecological and physiological factors contributing to the overall global distribution of vent endemic species.{\ensuremath{<}}br/{\ensuremath{>}}} } @article{soton340759, volume = {46}, number = {3}, title = {Tentaculitids in palynological preparations: New evidence from the Famennian (Late Devonian) of Southern Timan}, author = {J.E.A. Marshall and O.P. Telnova}, year = {2012}, pages = {228--230}, journal = {Paleontological Journal}, keywords = {Tentaculitids, Famennian, Southern Timan, Russia}, url = {https://eprints.soton.ac.uk/340759/}, abstract = {This is the first report of organic tentaculitid remains (zoomorphs) in palynological preparations of Famennian Age (Southern Timan, borehole Sosnovka-1). Earlier two similar finds have been described from the Frasnian of Poland as similar to embryonic and juvenile forms of dacryoconarids belonging to the orders Nowakiida and Stylionida.} } @article{soton350998, volume = {39}, number = {3-4}, month = {August}, author = {S{\'e}bastien Masson and Pascal Terray and Gurvan Madec and Jing-Jia Luo and Toshio Yamagata and Keiko Takahashi}, title = {Impact of intra-daily SST variability on ENSO characteristics in a coupled model}, journal = {Climate Dynamics}, pages = {681--707}, year = {2012}, keywords = {Diurnal cycle Coupled climate model El Ni{\~n}o-Southern Oscillation Ocean?atmosphere interactions}, url = {https://eprints.soton.ac.uk/350998/}, abstract = {This paper explores the impact of intra-daily Sea Surface Temperature (SST) variability on the tropical large-scale climate variability and differentiates it from the response of the system to the forcing of the solar diurnal cycle. Our methodology is based on a set of numerical experiments based on a fully global coupled ocean?atmosphere general circulation in which we alter (1) the frequency at which the atmosphere sees the SST variations and (2) the amplitude of the SST diurnal cycle. Our results highlight the complexity of the scale interactions existing between the intra-daily and inter-annual variability of the tropical climate system. Neglecting the SST intra-daily variability results, in our CGCM, to a systematic decrease of 15\% of El Ni{\~n}o{--}Southern Oscillation (ENSO) amplitude. Furthermore, ENSO frequency and skewness are also significantly modified and are in better agreement with observations when SST intra-daily variability is directly taken into account in the coupling interface of our CGCM. These significant modifications of the SST interannual variability are not associated with any remarkable changes in the mean state or the seasonal variability. They can therefore not be explained by a rectification of the mean state as usually advocated in recent studies focusing on the diurnal cycle and its impact. Furthermore, we demonstrate that SST high frequency coupling is systematically associated with a strengthening of the air-sea feedbacks involved in ENSO physics: SST/sea level pressure (or Bjerknes) feedback, zonal wind/heat content (or Wyrtki) feedback, but also negative surface heat flux feedbacks. In our model, nearly all these results (excepted for SST skewness) are independent of the amplitude of the SST diurnal cycle suggesting that the systematic deterioration of the air-sea coupling by a daily exchange of SST information is cascading toward the major mode of tropical variability, i.e. ENSO.} } @article{soton17483, volume = {6}, number = {6}, title = {Response of coral assemblages to the interaction between natural temperature variation and rare warm-water events in Kenyan reef lagoons}, author = {T.R. McClanahan and J. Mbui}, year = {2003}, pages = {551--563}, journal = {Ecosystems}, keywords = {bleaching, coral community structure, diversity, el ni{\~n}o?southern oscillation (enso), global climate change, resilience, stability, stress}, url = {https://eprints.soton.ac.uk/17483/}, abstract = {We examined changes in coral assemblages in four back-reef locations across the warm 1998 E1 Ni{\~n}o?Southern Oscillation (ENSO) event based on annually collected line-transect data from 3 years before and after this event. The physical locations of the reefs differed such that there was a 120\%?275\% warm-season range in the SDs of seawater temperatures but only minor differences in mean temperatures, based on 2 non-ENSO years. We tested the predictions that (a) rare warm-water events would produce fewer changes in eurythermal than stenothermal coral assemblages; and (b) after the disturbance, the stenothermal assemblages would more closely resemble the eurythermal ones. The 1998 event produced fewer changes in coral cover and community similarity among the assemblages in the reefs with high variation in temperature than in those with low variation in temperature. Despite the initially lower taxonomic richness in the eurythermal assemblage, there was an additional loss of taxonomic richness in the high and none in the stenothermal reefs. There was some evidence for taxonomic convergence, of the stenothermal towards the eurythermal reefs and a general loss of some of the branching taxa, such as branching Porites, Pavona, and Stylophora, and a relative increase in massive Porites and Favia. There was, however, moderate site specificity that did not produce true convergence. The eurythermal assemblages maintained the basic community structure but lost taxonomic richness, whereas the opposite was true for the stenothermal assemblages.} } @article{soton365127, volume = {399}, month = {August}, title = {Incursion of meteoric waters into the ductile regime in an active orogen}, author = {Catriona D. Menzies and Damon A.H. Teagle and Dave Craw and Simon C. Cox and Adrian J. Boyce and Craig D. Barrie and Stephen Roberts}, year = {2014}, pages = {1--13}, journal = {Earth and Planetary Science Letters}, keywords = {fluid flow, stable isotopes, alpine fault, fluid inclusions, southern alps, meteoric water}, url = {https://eprints.soton.ac.uk/365127/}, abstract = {Rapid tectonic uplift on the Alpine Fault, New Zealand, elevates topography, regional geothermal gradients, and the depth to the brittle ductile transition, and drives fluid flow that influences deformation and mineralisation within the orogen. Oxygen and hydrogen stable isotopes, fluid inclusion and Fourier Transform Infrared (FT-IR) analyses of quartz from veins which formed at a wide range of depths, temperatures and deformation regimes identify fluid sources and the depth of penetration of meteoric waters. Most veins formed under brittle conditions and with isotope signatures (?18OH2O = ?9.0 to +8.7?VSMOW and ?D=?73 to ?45?VSMOW?D=?73 to ?45?VSMOW) indicative of progressively rock-equilibrated meteoric waters. Two generations of quartz veins that post-date mylonitic foliation but endured further ductile deformation, and hence formation below the brittle to ductile transition zone (\>6?8 km\>6?8 km depth), preserve included hydrothermal fluids with ?D?D values between ?84 and ?52??52?, indicating formation from meteoric waters. FT-IR analyses of these veins show no evidence of structural hydrogen release, precluding this as a source of low ?D?D values. In contrast, the oxygen isotopic signal of these fluids has almost completely equilibrated with host rocks (?18OH2O = +2.3 to +8.7?). These data show that meteoric waters dominate the fluid phase in the rocks, and there is no stable isotopic requirement for the presence of metamorphic fluids during the precipitation of ductilely deformed quartz veins. This requires the penetration during orogenesis of meteoric waters into and possibly below the brittle to ductile transition zone.} } @article{soton351854, volume = {40}, number = {5}, month = {March}, author = {Michael P. Meredith and Peter J. Brown and Alberto C. Naveira Garabato and Lo{\"i}c Jullion and Hugh J. Venables and Marie-Jos{\'e} Messias}, title = {Dense bottom layers in the Scotia Sea, Southern Ocean: Creation, lifespan, and destruction}, journal = {Geophysical Research Letters}, pages = {933--936}, year = {2013}, keywords = {Dense bottom layers, Abyssal mixing, Southern Ocean, Overflows}, url = {https://eprints.soton.ac.uk/351854/}, abstract = {The lower limb of the Atlantic overturning circulation is renewed by dense waters from the Southern Ocean, a substantial portion of which flow through the Scotia Sea. We report dense bottom layers here, with gradients in temperature and salinity comparable to those seen near the surface of the Southern Ocean. These are overlain by layers with much weaker stratification, and are caused by episodic overflows of dense waters across the South Scotia Ridge, and topographic trapping within deep trenches. One such layer was found to be at least 3?4 years older than the water immediately above. The estimated vertical diffusivity to which this layer was subject is substantially less than the strong basin-average deep mixing reported previously. We conjecture that (a) vertical mixing in the Scotia Sea is strongly spatially inhomogeneous, and (b) the flushing of these layers, like their formation, is related to overflow events, and hence also strongly episodic.} } @article{soton373925, volume = {120}, number = {1}, month = {January}, author = {Michael P. Meredith and Andrew S. Meijers and Alberto C. Naveira Garabato and Peter J. Brown and Hugh J. Venables and E. Povl Abrahamsen and Lo{\"i}c Jullion and Marie-Jos{\'e} Messias}, title = {Circulation, retention, and mixing of waters within the Weddell-Scotia Confluence, Southern Ocean: The role of stratified Taylor columns}, journal = {Journal of Geophysical Research: Oceans}, pages = {547--562}, year = {2015}, keywords = {Weddell-Scotia Confluence, Taylor columns, Scotia Sea, Antarctic circumpolar current, Southern Ocean, mixing}, url = {https://eprints.soton.ac.uk/373925/}, abstract = {The waters of the Weddell-Scotia Confluence (WSC) lie above the rugged topography of the South Scotia Ridge in the Southern Ocean. Meridional exchanges across the WSC transfer water and tracers between the Antarctic Circumpolar Current (ACC) to the north and the subpolar Weddell Gyre to the south. Here, we examine the role of topographic interactions in mediating these exchanges, and in modifying the waters transferred. A case study is presented using data from a free-drifting, intermediate-depth float, which circulated anticyclonically over Discovery Bank on the South Scotia Ridge for close to 4 years. Dimensional analysis indicates that the local conditions are conducive to the formation of Taylor columns. Contemporaneous ship-derived transient tracer data enable estimation of the rate of isopycnal mixing associated with this column, with values of O(1000 m2/s) obtained. Although necessarily coarse, this is of the same order as the rate of isopycnal mixing induced by transient mesoscale eddies within the ACC. A picture emerges of the Taylor column acting as a slow, steady blender, retaining the waters in the vicinity of the WSC for lengthy periods during which they can be subject to significant modification. A full regional float data set, bathymetric data, and a Southern Ocean state estimate are used to identify other potential sites for Taylor column formation. We find that they are likely to be sufficiently widespread to exert a significant influence on water mass modification and meridional fluxes across the southern edge of the ACC in this sector of the Southern Ocean.} } @article{soton209177, volume = {25}, number = {1}, month = {January}, author = {Michael P. Meredith and Alberto C. Naveira Garabato and Andrew McC. Hogg and Riccardo Farneti}, title = {Sensitivity of the Overturning Circulation in the Southern Ocean to Decadal Changes in Wind Forcing}, journal = {Journal of Climate}, pages = {99--110}, year = {2012}, keywords = {Forcing, Ocean models, Decadal variability, Southern Ocean, Mixing}, url = {https://eprints.soton.ac.uk/209177/}, abstract = {The sensitivity of the overturning circulation in the Southern Ocean to the recent decadal strengthening of the overlying winds is being discussed intensely, with some works attributing an inferred saturation of the Southern Ocean CO2 sink to an intensification of the overturning circulation, while others have argued that this circulation is insensitive to changes in winds. Fundamental to reconciling these diverse views is to understand properly the role of eddies in counteracting the directly wind-forced changes in overturning. Here, the authors use novel theoretical considerations and fine-resolution ocean models to develop a new scaling for the sensitivity of eddy-induced mixing to changes in winds, and they demonstrate that changes in Southern Ocean overturning in response to recent and future changes in wind stress forcing are likely to be substantial, even in the presence of a decadally varying eddy field. This result has significant implications for the ocean?s role in the carbon cycle, and hence global climate.} } @article{soton49512, volume = {54}, number = {18-20}, title = {Iron?light interactions during the CROZet natural iron bloom and EXport experiment (CROZEX): II{--}Taxonomic responses and elemental stoichiometry}, author = {C.M. Moore and A.E. Hickman and A.J. Poulton and S. Seeyave and M.I. Lucas}, year = {2007}, pages = {2066--2084}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Phytoplankton, Iron limitation, Light, Southern Ocean}, url = {https://eprints.soton.ac.uk/49512/}, abstract = {The CROZet natural iron bloom and EXport experiment (CROZEX) investigated the annual phytoplankton bloom that occurs in the vicinity of the Crozet plateau in the Polar Frontal Zone (PFZ) of the Southern Ocean. Shipboard manipulation experiments designed to investigate potential responses of phytoplankton community structure and elemental stoichiometry to iron (Fe) and/or light perturbation are compared to in situ data collected during CROZEX. The outcome of individual experiments was strongly influenced by initial phytoplankton community structure. For example Fe amendment of high (\>8 ?M) silicic acid waters resulted in a strong response by medium-sized diatoms, including Eucampia antarctica. In contrast Phaeocystis antarctica dominated the community response to increased Fe within an experiment initiated during the early declining stage of the bloom. Conversely, small diatoms responded more strongly to increased irradiance, while the population of very large diatoms remained relatively static. Consistent with experimental results, the intense natural blooms north of the Crozet plateau were observed to be dominated by either P. antarctica or medium-sized diatoms while small phytoplankton and large diatoms dominated lower-chlorophyll waters in the south. In situ data and results from experiments supported previous observations of lower nitrate to phosphate removal ratios for diatoms compared to P. antarctica. Experimental and in situ data also supported previous work showing that silicic acid to nitrate removal ratios can be reduced under conditions of enhanced Fe availability. Higher irradiance decreased this ratio still further. Interactions between Fe and light were thus likely to have contributed to the observed decoupling of the major element cycles between the intense bloom that occurs north of Crozet and more typical PFZ conditions to the South. Specifically, silicic acid became exhausted in both systems, with drawdown in the south potentially resulting from co-limitation of diatom growth by Fe and light. In contrast, increased Fe supply in the north enhanced nitrogen, phosphorous and carbon drawdown in ratios that were dependent on the community composition of the resultant bloom. {\ensuremath{<}}br/{\ensuremath{>}}} } @article{soton49511, volume = {54}, number = {18-20}, title = {Iron?light interactions during the CROZet natural iron bloom and EXport experiment (CROZEX) I: Phytoplankton growth and photophysiology}, author = {C.M. Moore and S. Seeyave and A.E. Hickman and J.T. Allen and M.I. Lucas and H. Planquette and R.T. Pollard and A.J. Poulton}, year = {2007}, pages = {2045--2065}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Phytoplankton, Iron limitation, Light, Southern Ocean}, url = {https://eprints.soton.ac.uk/49511/}, abstract = {The CROZet natural iron bloom and EXport experiment (CROZEX) investigated phytoplankton blooms in the vicinity of the Crozet Plateau in the polar frontal zone (PFZ) of the Southern Ocean. Peak chlorophyll concentrations reached during an intense bloom within naturally iron (Fe)-fertilised regions north of the plateau were an order of magnitude higher than those observed in deeper mixed layers and low-Fe waters to the south. To establish the factors influencing phytoplankton dynamics, a suite of in situ phytoplankton physiological measurements and shipboard Fe?light perturbation experiments was performed. Addition of Fe in experiments performed during bloom decline north of the plateau resulted in increased accumulation of phytoplankton biomass and changes in a number of phytoplankton physiological characteristics. In particular photosystem II (PSII) photochemical efficiencies (Fv/Fm) measured by fast repetition rate fluorometry increased above in situ values within 24 h of Fe amendment, suggesting that Fe stress had contributed to bloom termination. In contrast, responses to Fe amendment were minor within an experiment initiated in low-silicic acid, post-bloom waters south of the Plateau. Within the intense bloom in the north, light limitation due to self-shading may have constrained the peak phytoplankton standing stock. However, in the absence of Fe amendment, incubation at higher than in situ irradiance levels had little influence on phytoplankton biomass accumulation for declining bloom populations. Instead reduced Fv/Fm, reflecting increased photoinhibitory damage to PSII, was observed in high-light incubations and was also apparent in situ. Interactions between Fe and light availability thus influenced phytoplankton physiology and growth and potentially contributed to bloom longevity during CROZEX. {\ensuremath{<}}br/{\ensuremath{>}}} } @article{soton49519, volume = {54}, number = {18-20}, title = {234Th-derived particulate organic carbon export from an island-induced phytoplankton bloom in the Southern Ocean}, author = {P.J. Morris and R. Sanders and R. Turnewitsch and S. Thomalla}, year = {2007}, pages = {2208--2232}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {CROZEX, Crozet, Southern Ocean, 234Th, Carbon export, POC}, url = {https://eprints.soton.ac.uk/49519/}, abstract = {It has long been recognised that some oceanic regions have persistently low-chlorophyll levels, even though there are abundant inorganic nutrients. Studies have shown that these high-nutrient low-chlorophyll (HNLC) areas are depleted in iron, an essential micronutrient. In these regions biological production can be enhanced with artificial mesoscale iron fertilisation. However, the ability of iron-induced blooms to efficiently sequester carbon to mesopelagic depths is still an open question. It is hypothesised that sub-Antarctic islands in the HNLC Southern Ocean are also a source of iron and thus fuel the natural phytoplankton blooms observed in their proximity, thereby enhancing levels of particulate organic carbon (POC) export. To test the third part of this hypothesis, POC export was measured in the Southern Ocean region of the Crozet Islands (52?E, 46?S) during the austral summer of 2004/2005 as part of the CROZEX project. Based on satellite imagery, a high-chlorophyll region (maximum concentration=4 ?g l?1) north and downstream of the islands was distinguished from a low-chlorophyll region (typical concentration=0.3 ?g l?1) south and upstream of the islands. POC export estimates were obtained by using the naturally occurring particle-reactive radionuclide tracer 234Th. POC export was initially 15 mmol C m?2 d?1 in the high-chlorophyll bloom region, compared with 5 mmol C m?2 d?1 in the low-chlorophyll, non-bloom region. After a moderately small bloom at the southern control stations (max concentration=0.7 ?g l?1) the spatial variability in POC export was lost, resulting in equally high levels of POC export (ca. 20 mmol C m?2 d?1) throughout the study region. Comparison of 234Th-derived POC export with estimates of new production, calculated from nitrate budgets, revealed evidence for a decoupling of new and export production, with this effect most apparent within the northern bloom area. In addition to methodological issues this apparent decoupling of new and export production could be due to a buildup of dissolved organic nitrogen within the bloom region, thus reducing the amount of POC available for export to mesopelagic depths.} } @article{soton477561, volume = {128}, number = {6}, month = {June}, title = {Zonal distribution of circumpolar deep water transformation rates and its relation to heat content on Antarctic shelves}, author = {Aditya Narayanan and Sarah T. Gille and Matthew R. Mazloff and Marcel D. du Plessis and K. Murali and Fabien Roquet}, year = {2023}, journal = {Journal of Geophysical Research: Oceans}, keywords = {Antarctica, Circumpolar Deep Water, Southern Ocean, ice shelves}, url = {https://eprints.soton.ac.uk/477561/}, abstract = {We analyze 15-year of observational data and a 5-year Southern Ocean model simulation to quantify the transformation rates of Circumpolar Deep Water (CDW) and the associated heat loss to the surface. This study finds that over the continental shelves of East Antarctica and the Weddell and Ross Seas, surface buoyancy fluxes transform {$\sim$}4.4 Sv of surface waters into CDW, providing a path for CDW to lose heat to the surface. In addition, {$\sim$}6.6 Sv of CDW are mixed with surface waters in the Weddell and Ross subpolar gyres. In contrast, enhanced stratification inhibits the outcropping of CDW isopycnals, reducing their transformation rates by a factor of {$\sim$}8 over the continental shelf and by a factor of {$\sim$}3 over the deeper ocean in the Amundsen and Bellingshausen Seas. The CDW retains its offshore warm properties as it intrudes over the continental shelves, resulting in elevated bottom temperatures there. This analysis demonstrates the importance of processes in subpolar gyres to erode CDW and to facilitate further transformation on the continental shelves, significantly reducing the heat able to access ice shelf fronts. This sheltering effect is strongest in the western Weddell Sea and tends to diminish toward the east, which helps explain the large zonal differences in continental-shelf bottom temperatures and the melt rates of Antarctic ice shelves.} } @article{soton350741, volume = {92}, month = {August}, title = {A new species of Eualus Thallwitz, 1891 and new record of Lebbeus antarcticus (Hale, 1941) (Crustacea: Decapoda: Caridea: Hippolytidae) from the Scotia Sea}, author = {Verity Nye and Jon Copley and Katrin Linse}, year = {2013}, pages = {145--156}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Biodiversity, Deep-Sea, Hydrothermal vents, Southern Ocean, Phylogenetics, Polar}, url = {https://eprints.soton.ac.uk/350741/}, abstract = {Eleven specimens representing two hippolytid genera, Eualus Thallwitz, 1891 and Lebbeus White, 1847, were sampled recently from the Scotia Sea (1517-2598 m). Seven specimens are described and illustrated as Eualus amandae sp. nov., and its morphology is compared with those of previously described species. Four female specimens, morphologically consistent with Lebbeus antarcticus (Hale, 1941), are described and illustrated to supplement previous descriptions of this rarely collected bathyal species. Partial COI mtDNA and 18S rDNA sequences were generated for both species. Only limited DNA sequences are available for species of Hippolytidae and the COI trees presented are used to illustrate that the new species is genetically distinct from other species for which COI sequences are available. The presence of fixed and unique mutations in the COI sequences of the new species indicates that they are genetically distinct from all other species in GenBank. This record enhances existing knowledge of Antarctic invertebrate biodiversity and species richness of decapod crustaceans in the Southern Ocean.} } @article{soton422496, month = {April}, title = {Evaluating the effects of climate change in the southern Benguela upwelling system using the Atlantis modelling framework}, author = {Kelly Ortega-Cisneros and Kevern L. Cochrane and Elizabeth A. Fulton and Rebecca Gorton and Ekaterina Popova}, year = {2018}, pages = {1--15}, journal = {Fisheries Oceanography}, keywords = {Climate change, Ecosystem impacts, Fishing, Southern Benguela}, url = {https://eprints.soton.ac.uk/422496/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}The ocean is affected by multiple anthropogenic stressors including climate change, the effects of which are already evident in many ocean ecosystems. The ABACuS v2 end-to-end model together with climate projections from the NEMO-MEDUSA 2.0 model were used to evaluate the effects of fishing, warming and horizontal and vertical mixing on the southern Benguela upwelling system. Of the drivers examined in this study, warming had the greatest effect on species biomass, with mainly negative effects. The magnitude of the impacts of warming intensified from the RCP 2.6 to the 8.5 emission scenario. Fishing negatively affected demersal and large pelagic fish, which in turn resulted in a biomass increase of forage fish due to a decrease in predation pressure. Water mixing was found to have minor indirect effects on zooplankton biomass and fish. The responses of species and species groups to the combined effects of fishing and warming were approximately equally divided between additive, synergistic and antagonistic. Interpretation of our model results suggests that the southern Benguela system is likely to be affected by climate change, including substantial changes in the abundance of some species important to the region's fisheries. Future planning for fisheries needs to take this into account, including through management that strives to maintain the resilience of key species and the system as a whole. In line with previous studies on the southern Benguela, the results reinforce the importance of including consideration of the indirect and combined impacts of climate change and fishing in management and planning.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton475018, volume = {47}, number = {1}, title = {Growth rates and ages of some key tree species from subantarctic Auckland and Campbell Islands}, author = {Jonathan G. Palmer and Chris S.M. Turney and Zo{\"e} A. Thomas and Pavla Fenwick and Sarah J. Richardson and Janet M. Wilmshurst and Matt S. McGlone}, year = {2023}, note = {Funding Information: We wish to express our thanks to the captain and crew of the MV Akademik Shokalskiy and Henk Haazen and Kali Kahn on the Tiama for help in the field. This work was supported by the Australasian Antarctic Expedition 2013?2014, the Australian Research Council (CE170100015; FL100100195, Funding Information: FT120100004, and DP130104156) and the University of New South Wales. SJR, JMW and MSM were supported by SSIF funding for Crown Research Institutes from the New Zealand Ministry of Business, Innovation and Employment?s Science and Innovation Group. Research on the New Zealand subantarctic Auckland and Campbell Islands was undertaken under Department of Conservation National Authorisation Numbers 37687-FAU and 39761-RES. Funding Information: We wish to express our thanks to the captain and crew of the MV Akademik Shokalskiy and Henk Haazen and Kali Kahn on the Tiama for help in the field. This work was supported by the Australasian Antarctic Expedition 2013?2014, the Australian Research Council (CE170100015; FL100100195, FT120100004, and DP130104156) and the University of New South Wales. SJR, JMW and MSM were supported by SSIF funding for Crown Research Institutes from the New Zealand Ministry of Business, Innovation and Employment?s Science and Innovation Group. Research on the New Zealand subantarctic Auckland and Campbell Islands was undertaken under Department of Conservation National Authorisation Numbers 37687-FAU and 39761-RES.}, journal = {New Zealand Journal of Ecology}, keywords = {forest conservation, radiocarbon dating, remote islands, Southern Ocean, southern tree limit, World Heritage Area}, url = {https://eprints.soton.ac.uk/475018/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Interspecific variation in tree growth rate and maximum age is central to understanding and predicting the dynamics of forest ecosystems. While there are abundant sources of this information for economically important New Zealand timber species and other common tree species, data for trees from subantarctic environments are almost entirely lacking. Here we present measurements of growth from Auckland and Campbell Islands for three species: Metrosideros umbellata (southern r{\=a}t{\=a}; Myrtaceae, n = 1 site), a canopy dominant; Dracophyllum sp. (inaka; Ericaceae, n = 5 sites), a widespread small tree; and Olearia lyallii (t{\=u}pare, subantarctic tree daisy; Asteraceae, n = 2 sites), a species native to Snares Island that has naturalised on the Auckland Islands. Our data showed large differences in tree growth rates among and within species across islands. Growth rates varied eight-fold (i.e. from 0.34 mm yr{\ensuremath{<}}sup{\ensuremath{>}}?1{\ensuremath{<}}/sup{\ensuremath{>}} to 2.78 mm yr{\ensuremath{<}}sup{\ensuremath{>}}?1{\ensuremath{<}}/sup{\ensuremath{>}}), being greatest in Olearia lyallii, least in Dracophyllum sp. and intermediate in Metrosideros umbellata. Comparisons of the five Dracophyllum sites suggest that these trees experience reduced growth rates and reach older ages when in competition with the bigger southern r{\=a}t{\=a} (M. umbellata) trees, possibly due to the larger southern r{\=a}t{\=a} providing protection from wind-throw. Measurements of resprouted southern r{\=a}t{\=a} trees showed a variable juvenile-phase radial growth rate, highlighting the need for caution in extrapolating the likely ages of bigger trees. Remeasured individuals of Olearia lyallii growing among taller southern r{\=a}t{\=a} trees showed slow growth rates compared to much faster rates seen in a nearby monospecific stand. Overall, the variability in growth seen by all three species illustrates that tree size cannot be used to indicate age in these subantarctic islands.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton476220, volume = {266}, number = {8}, month = {August}, author = {Panayiotis Panaretos and Paul G. Albert and Zo{\"e} A. Thomas and Chris S.M. Turney and Charles R. Stern and G. Jones and Alan N. Williams and Victoria C. Smith and Alan G. Hogg and Christina J. Manning}, note = {Funding Information: This project was supported by the Australian Research Council (grant no. DE200100907 and DP130104156). P. Panaretos was supported by a UNSW Summer Vacation Research Scholarship. P.G.A and G.J are funded through a UK Research and Innovation Future Leaders Fellowship (MR/S035478/1). We thank Rebecca Smith for providing constructive comments on an earlier version of this manuscript. We thank the Falkland Islands Government for permission to undertake sampling on the island (permit number: R07/2011). Funding Information: This project was supported by the Australian Research Council (grant no. DE200100907 and DP130104156 ). P. Panaretos was supported by a UNSW Summer Vacation Research Scholarship. P.G.A and G.J are funded through a UK Research and Innovation Future Leaders Fellowship ( MR/S035478/1 ). We thank Rebecca Smith for providing constructive comments on an earlier version of this manuscript. We thank the Falkland Islands Government for permission to undertake sampling on the island (permit number: R07/2011). Publisher Copyright: {\copyright} 2021}, title = {Distal ash fall from the mid-Holocene eruption of Mount Hudson (H2) discovered in the Falkland Islands: New possibilities for Southern Hemisphere archive synchronisation}, journal = {Quaternary Science Reviews}, year = {2021}, keywords = {Antarctic, Cryptotephra, Hudson, Patagonia, South America, South Atlantic, Southern Ocean, Southern volcanic zone, Tephrochronology}, url = {https://eprints.soton.ac.uk/476220/}, abstract = {Cryptotephra deposits (microscopic volcanic ash) are important geochronological tools that can be used to synchronize records of past environmental change. Here we report a distal cryptotephra from a Holocene peat sequence (Canopus Hill) in the Falkland Islands, in the South Atlantic. Using geochemical analysis (major- and trace-element) of individual volcanic glass shards, we provide a robust correlation between this cryptotephra and the large mid-Holocene explosive eruption of Mt. Hudson in Patagonia, Chile (H2; {$\sim$}3.9 ka cal BP). The occurrence of H2 as a cryptotephra in the Falkland Islands significantly increases the known distribution of this marker horizon to more than 1200 km from the volcano, a threefold increase of its previous known extent. A high-resolution radiocarbon chronology, based on terrestrial plant macrofossils, dates the H2 tephra to 4265 {$\pm$} 65 cal yr BP, suggesting that the eruption may have occurred slightly earlier than previously reported. The refined age and new geochemical reference dataset will facilitate the identification of the H2 tephra in other distal locations. The high concentration of glass shards in our peat sequence indicates that the H2 tephra may extend well beyond the Falkland Islands and we recommend future studies search for its presence across the sub-Antarctic islands and Antarctic Peninsula as a potentially useful chronological marker.} } @article{soton44170, volume = {22}, number = {3}, title = {Coherent coastal sea level variability at inter-decadal and inter-annual scales from tide gauges}, author = {A. Papadopoulos and M.N. Tsimplis}, year = {2006}, pages = {625--639}, journal = {Journal of Coastal Research}, keywords = {teleconnections, indices, regional sea level, North Atlantic Oscillation, El Ni{\~n}o?Southern Oscillation, Southern Oscillation Index, Arctic Oscillation, Pacific Decadal Oscillation}, url = {https://eprints.soton.ac.uk/44170/}, abstract = {Coastal sea level measured from tide gauges exhibits coherent variability at interannual and decadal scales. We investigate sea-level variability of large geographic areas using annual mean sea-level values obtained from the longest available records of coastal observations. Eight sea-level regional indices are constructed for the Atlantic and the Pacific Ocean basins. High coherency of sea-level variability at the decadal timescales between different oceanic regions is observed. The role of large-scale atmospheric forcing is then examined by comparison with the El Ni{\~n}o?Southern Oscillation (ENSO) and the North Atlantic Oscillation (NAO). Strong correlation between the NAO and the second empirical orthogonal function (EOF) of the northwest Atlantic data set was observed. The second EOF is also significantly correlated with the latitudinal position of Gulf Stream and the Arctic Oscillation (AO). Sea-level changes in the northeast Atlantic are driven by the NAO. Correlation with the AO was also observed. In the Pacific Ocean, ENSO dominates sea-level variability along the eastern and southwest sides of the basin. ENSO signatures appear also in the southwest Atlantic, indicating teleconnection patterns. It is proposed that ENSO-related variability in this region is forced through the Pacific?South American teleconnection mechanism. The correlation between southwest Atlantic sea level and ENSO increased after 1980. Sea-level variability on decadal scales in the northwest Pacific region is influenced by the Pacific Decadal Oscillation.{\ensuremath{<}}br/{\ensuremath{>}}} } @article{soton49374, volume = {54}, number = {16-17}, title = {A note on the genetic similarity between shallow- and deep-water Epistominella vitrea (Foraminifera) in the Antarctic}, author = {J. Pawlowski and S.S. Bowser and A.J. Gooday}, year = {2007}, pages = {1720--1726}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Genetic diversity, rRNA, Foraminifera, Protists, Southern Ocean}, url = {https://eprints.soton.ac.uk/49374/}, abstract = {Many Antarctic species are known to have large bathymetric ranges. However, little is known about the genetic diversity of populations living at different depths. In certain microfauna- and meiofauna-sized taxa, some morphospecies can be divided into several cryptic genetic species. To test whether cryptic diversity is linked with depth of occurrence in Southern Ocean foraminifera, we compared ribosomal DNA sequences of selected calcareous foraminiferal species from shallow localities in McMurdo Sound and deep ones in the Weddell Sea. We found that at least one species, Epistominella vitrea, was genetically almost identical between the two localities, having a bathymetric range of over 1000 m. Our study provides molecular evidence for an extraordinarily large depth migration of Antarctic shelf foraminifera. It also suggests a relationship between populations of foraminifera from widely separated geographic regions of the Southern Ocean.} } @article{soton345901, volume = {55}, number = {5}, month = {November}, author = {R. Pinhasi and B. Gasparian and K. Wilkinson and R. Bailey and G. Bar-Oz and A. Bruch and C. Chataigner and D. Hoffmann and R. Hovsepyan and S. Nahapetyan and A.W.G. Pike and D. Schreve and M. Stephens}, title = {Hovk 1 and the Middle and Upper Palaeolithic of Armenia}, journal = {Journal of Human Evolution}, pages = {803--816}, year = {2008}, keywords = {neandertals, chronology, middle-upper paleolithic transition, southern caucasus, levallois, paleoenvironment}, url = {https://eprints.soton.ac.uk/345901/}, abstract = {The territory of present day Armenia is a geographic contact zone between the Near East and the northern Caucasus. Armenian Middle and Upper Paleolithic records are both few and patchy as a result of the historical paucity of systematic archaeological research in the country. Consequently, it is currently difficult to correlate the Armenian Middle and Upper Paleolithic records with those from other neighboring regions. We present new archaeological and chronometric data (luminescence, U-Th, and 14C) from our ongoing research at Hovk 1 Cave in northeast Armenia. We discuss in particular two activity phases in Hovk 1 Cave for which we have outline chronometric data: (1) an early Middle Paleolithic occupational phase, dated by optically stimulated luminescence (OSL) to 104 {$\pm$} 9.8 ka BPOSL; and (2) a Paleolithic occupational phase characterized by microlithic flakes dated by AMS 14C to 39,109 {$\pm$} 1,324 calibrated years BPHulu. The two phases are separated by a hiatus in hominin occupation corresponding to MIS 4 and an episode in early MIS 3. These chronometric data, taken together with the preliminary paleoenvironmental reconstruction of the Hovk 1 Cave and environment, suggest that these activity phases represent short-lived and seasonal use of the cave presumably by small groups of hunters during episodes of mild climate. Neither tool manufacture nor butchery appears to have taken place within the cave, and consequently, the archaeological record included, for the most part, finished tools and blanks. We address the chronology and techno-typological aspects of Hovk 1 lithics in relation to: (1) the Paleolithic records of Armenia, and (2) the broader interregional context of early Middle Paleolithic hominin occupation and the Middle-Upper Paleolithic transition in the Caucasus} } @article{soton468686, volume = {35}, number = {11}, month = {November}, author = {P. A. Pistorius and M. A. Me{\"y}er and R. R. Reisinger and S. P. Kirkman}, note = {Funding Information: Acknowledgments We would like to thank the Department of Environmental Affairs who provided logistic and financial support for the Prince Edward Island autumn survey. We are grateful for the insightful comments received from two anonymous reviewers. Copyright: Copyright 2012 Elsevier B.V., All rights reserved.}, title = {Killer whale predation on subantarctic fur seals at Prince Edward Island, Southern Indian Ocean}, year = {2012}, journal = {Polar Biology}, pages = {1767--1772}, keywords = {Apex predators, Feeding ecology, Population regulation, Southern Ocean}, url = {https://eprints.soton.ac.uk/468686/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Killer whales at subantarctic Marion Island have been subjected to several scientific studies. In contrast, up until recently, there has been only one record of these animals documented for neighbouring Prince Edward Island. We here report on killer whale observations at Prince Edward Island during March 2012. During 3 days of opportunistic observations at a fur seal colony on the island, killer whales were sighted on six occasions. These probably represented three different pods numbering 11 individuals in total. During all sightings, individuals were seen hunting subantarctic fur seal pups, with four successful predatory events observed.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton455663, volume = {7}, number = {11}, month = {June}, author = {Pierre Pistorius and Mark Hindell and Robert Crawford and Azwianewi Makhado and Bruce Dyer and Ryan Reisinger}, title = {At-sea distribution and habitat use in king penguins at sub-Antarctic Marion Island}, journal = {Ecology and Evolution}, pages = {3894--3903}, year = {2017}, keywords = {foraging, habitat selection, movement, seabirds, Southern Ocean}, url = {https://eprints.soton.ac.uk/455663/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}King penguins make up the bulk of avian biomass on a number of sub-Antarctic islands where they have a large functional effect on terrestrial and marine ecosystems. The same applies at Marion Island where a substantial proportion of the world population breeds. In spite of their obvious ecological importance, the at-sea distribution and behavior of this population has until recently remained entirely unknown. In addressing this information deficiency, we deployed satellite-linked tracking instruments on 15 adult king penguins over 2 years, April 2008 and 2013, to study their post-guard foraging distribution and habitat preferences. Uniquely among adult king penguins, individuals by and large headed out against the prevailing Antarctic Circumpolar Current, foraging to the west and southwest of the island. On average, individuals ventured a maximum distance of 1,600 km from the colony, with three individuals foraging close to, or beyond, 3,500 km west of the colony. Birds were mostly foraging south of the Antarctic Polar Front and north of the southern boundary of the Antarctic Circumpolar Current. Habitat preferences were assessed using boosted regression tree models which indicated sea surface temperate, depth, and chorophyll a concentration to be the most important predictors of habitat selection. Interestingly, king penguins rapidly transited the eddy-rich area to the west of Marion Island, associated with the Southwest Indian Ocean Ridge, which has been shown to be important for foraging in other marine top predators. In accordance with this, the king penguins generally avoided areas with high eddy kinetic energy. The results from this first study into the behavioral ecology and at-sea distribution of king penguins at Marion Island contribute to our broader understanding of this species.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton49509, volume = {54}, number = {18-20}, title = {Dissolved iron in the vicinity of the Crozet Islands, Southern Ocean}, author = {H. Planquette and P.J. Statham and G.R. Fones and M.A. Charette and C.M. Moore and I. Salter and F.H. Nedelec and S.L. Taylor and M. French and A.R. Baker and N. Mahowald and T.D. Jickells}, year = {2007}, pages = {1999--2019}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Dissolved iron, Crozet Islands, Southern Ocean, HNLC}, url = {https://eprints.soton.ac.uk/49509/}, abstract = {The annual phytoplankton bloom occurring north of the Crozet Plateau provides a rare opportunity to examine the hypothesis that natural iron fertilization can alleviate high-nutrient low-chlorophyll (HNLC) conditions normally associated with the Southern Ocean. Therefore, during CROZet natural iron bloom and EXport experiment (CROZEX), a large multidisciplinary study performed between November 2004 and January 2005, measurements of total dissolved iron (DFe0.2 ?m) were made on seawater from around the islands and atmospheric iron deposition estimated from rain and aerosol samples.{\ensuremath{<}}br/{\ensuremath{>}}{\ensuremath{<}}br/{\ensuremath{>}}DFe concentrations were determined by flow injection analysis with N,N-dimethyl-p-phenylenediamine dihydrochloride (DPD) catalytic spectrophotometric detection. DFe concentrations varied between 0.086 and 2.48 nM, with low values in surface waters. Enrichment of dissolved iron (\>1 nM) at close proximity to the islands suggests that the plateau and the associated sediments are a source of iron. Waters farther north also appear to be affected by this input of coastal and shelf origin, although dissolved iron concentrations decrease as a function of distance to the north of the plateau with a gradient of 0.07 nM km?1 at the time of sampling. Using lateral and vertical diffusion coefficients derived from Ra isotope profiles and also estimates of atmospheric inputs, it was then possible to estimate a DFe concentration of 0.55 nM to the north of the islands prior to the bloom event, which is sufficient to initiate the bloom, the lateral island source being the largest component. A similar situation is observed for other Sub-Antarctic Islands such as Kerguelen, South Georgia, that supply dissolved iron to their surrounding waters, thus enhancing chlorophyll concentrations.} } @article{soton68673, volume = {115}, number = {1-2}, month = {June}, author = {H{\'e}l{\`e}ne Planquette and Gary R. Fones and Peter J. Statham and Paul J. Morris}, title = {Origin of iron and aluminium in large particles (\> 53 ?m) in the Crozet region, Southern Ocean}, journal = {Marine Chemistry}, pages = {31--42}, year = {2009}, keywords = {Suspended particulate matter, Iron, Aluminium, HNLC, CROZEX, Southern Ocean, Crozet Islands}, url = {https://eprints.soton.ac.uk/68673/}, abstract = {Natural iron fertilization processes are occurring around the Crozet Islands (46?26?S?52?18?E), thus relieving the water masses from the normally encountered High Nutrients Low Chlorophyll (HNLC) conditions of the Southern Ocean. During austral summers 2004/2005 and 2005/2006, iron and aluminium concentrations were investigated in large particles (\> 53 ?m) collected from just below the mixed layer at stations under the influence of island inputs, and also in adjacent HNLC waters. These large particles are anticipated to sink out of the mixed layer, and to reflect the net effects of input and cycling of these elements in the overlying mixed layer. Labile and refractory fractions were determined by a two-stage leaching technique. Data showed that water masses downstream of the islands were enriched in total iron and aluminium (0.25?2.68 nmol L? 1 and 0.34?3.28 nmol L? 1 respectively), relative to the southern HNLC control sites (0.15?0.29 nmol L? 1 for Fe and 0.12?0.29 nmol L? 1 for Al), with only a small fraction (typically \< 1\%) being acid leachable in both environments. Particulate iron predominantly derived from the island system represents a significant fraction of the total water column iron inventory and may complement dissolved Fe inputs that help support the high summer productivity around the Crozet islands.} } @article{soton49119, volume = {54}, number = {18-20}, month = {October}, author = {R. Pollard and R. Sanders and M. Lucas and P. Statham}, title = {The Crozet natural iron bloom and export experiment (CROZEX)}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, pages = {1905--1914}, year = {2007}, keywords = {natural iron fertilization, ocean circulation, primary production, carbon fixation, nutrient cycles, southern ocean}, url = {https://eprints.soton.ac.uk/49119/}, abstract = {This special issue describes the findings of the first planned natural iron fertilisation experiment in the Southern Ocean, the CROZet natural iron bloom and EXport experiment (CROZEX), which took place from November 2004 to January 2005. The bloom that occurs annually north of the Crozet Islands and Plateau (Crozet) was surveyed and compared with a high-nutrient low-chlorophyll (HNLC) region south of Crozet. Papers in this volume confirm that iron from Crozet fertilised the bloom and that phytoplankton production rates and most export flux estimates were much larger in the bloom area than in the HNLC control area. This introductory paper summarises the reasons for choosing the Crozet area, and provides an overview of the two cruises that comprised CROZEX and their major findings.} } @article{soton6097, volume = {49}, number = {16}, title = {Physical controls on biogeochemical zonation in the Southern Ocean}, author = {R.T. Pollard and M.I. Lucas and J.F. Read}, year = {2002}, pages = {3289--3305}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {southern ocean, antarctic circumpolar current, nitrate, silicate}, url = {https://eprints.soton.ac.uk/6097/}, abstract = {The primary control on the N?S zonation of the Southern Ocean is the wind-induced transport of the Antarctic Circumpolar Current (ACC). The ACC divides the Southern Ocean into three major zones: the Subantarctic Zone (SAZ) north of the ACC; the ACC transport zone; and the zone south of the ACC (SACCZ). The zone of ACC transport is most often subdivided into two zones, the Polar Frontal Zone (PFZ) and the Antarctic Zone (AAZ), but it may be appropriate to define more subzones or indeed only one at some longitudes. To maintain geostrophic balance, isopycnals must slope upwards to the south across the ACC, thus raising nutrient-rich deep water closer to the surface as one goes polewards. In addition, silicate concentrations increase polewards along isopycnals because of diapycnic mixing with silicate-rich bottom water. Surface silicate concentrations therefore decrease northwards from high levels in the SACCZ to low levels in the SAZ. Within the SAZ and PFZ and even in the northern part of the AAZ, silicate levels may drop to limiting levels for siliceous phytoplankton production during summer. Nitrate concentrations also decrease northwards, but only become limiting in the Subtropical Zone north of the SAZ. The second circumpolar control is the changing balance of stratification, with temperature dominating near-surface stratification in the SAZ and salinity dominating further south because of fresh water input to the surface from melting ice. This results in circumpolar features such as the subsurface 2?C temperature minimum and the subduction of the salinity minimum of Antarctic Intermediate Water, which are often but not always associated with frontal jets and large transports. The transport of the ACC is dynamically constrained into narrow bands, the number and latitudinal location of which are controlled by the bathymetry and so vary with longitude. Thus it is not the fronts that are circumpolar, but the total ACC transport and scalar properties of the salinity and temperature fields. Evidence of summer silicate and nitrate uptake in all zones (SAZ, PFZ and AAZ) shows that there is productivity despite their high-nutrient low-chlorophyll status. Blooms covering large areas (say 400 km across) in the PFZ and AAZ are found in the vicinity of submarine plateaux, which suggest benthic iron fertilization.} } @techreport{soton21034, type = {Project Report}, title = {RRS "Discovery" cruises 285-286, 3 Nov - 10 Dec 2004; 13 Dec 2004 - 21 Jan 2005. CROZet circulation, iron fertilization and EXport production experiment (CROZEX)}, author = {R.T. Pollard and R. Sanders}, publisher = {Southampton Oceanography Centre, University of Southampton}, year = {2006}, series = {60}, keywords = {acronym, circulation, Crozet Plateau, CROZEX, cruise 285 2004, cruise 286 2004-05, Discovery, export production, natural iron fertilization, phytoplankton productivity, Southern Ocean}, url = {https://eprints.soton.ac.uk/21034/}, abstract = {CROZEX (CROZet circulation, iron fertilization and EXport production experiment) is a complex, multidisciplinary project to examine the causes and consequences of the annual bloom that forms north of the Crozet Plateau in the southwest Indian Ocean sector of the Southern Ocean. The CROZEX cruises took place between 3 Nov 2004 and 21 Jan 2005. Much of the cruise was planned around a series of Major Stations every two or three days at each of which a series of CTD casts was made to sample physical parameters, currents, nutrients, phytoplankton, iron and phytoplankton productivity, 234Th and SAPS. Other work at each Major Station included zooplankton nets, radium samples, Pelagra deployment and occasionally other sampling such as LHPR tows, neodynium, mooring deployment, coring, Argo float deployment and water collection{\ensuremath{<}}br/{\ensuremath{>}}for bioassay experiments. Five moorings were deployed, one of which was recovered at the end of the cruise. The other four, with 6 sediment traps in total were deployed for a year. In between Major Stations there were some additional sCTD casts to fill in hydrographic details and SeaSoar tows. Underway measurements included thermosalinograph and fluorimeter, hull-mounted ADCP, surface nutrients, iron from a special TMS (trace metal) fish, CO2, analytical flow cytometry, aerosols and rain.} } @article{soton49505, volume = {54}, number = {18-20}, title = {Large-scale circulation around the Crozet Plateau controls an annual phytoplankton bloom in the Crozet Basin}, author = {R.T. Pollard and H.J. Venables and J.F. Read and J.T. Allen}, year = {2007}, pages = {1915--1929}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Circulation, Hydrography, Drifters, Subsurface drifters, Altimetry, Algal blooms, Southern Ocean, Polar Frontal Zone, Crozet Plateau, 40?50?S, 40?60?E}, url = {https://eprints.soton.ac.uk/49505/}, abstract = {The circulation in the vicinity of the Crozet Plateau in the Southwest Indian Ocean sector of the Southern Ocean is examined using hydrographic sections, Argo floats, surface drifters, and satellite altimetry. All four techniques confirm that a major branch of the Antarctic Circumpolar Current, the SubAntarctic Front (SAF), flows anticyclonically round the Del Ca{\~n}o Rise west of the Crozet Plateau, i.e. eastward to the south of the Del Ca{\~n}o Rise, then northward and sometimes northwestward into the Crozet Basin, before turning back eastward in a combined front with the Agulhas Return Current and the SubTropical Front. This S-bend in the SAF is a permanent feature, controlled by the bathymetry, as has been inferred previously by Pollard and Read [Pollard, R.T., Read, J.F., 2001. Circulation pathways and transports of the Southern Ocean in the vicinity of the Southwest Indian Ridge. Journal of Geophysical Research, 106(C2), 2881?2898]. Similar, but much weaker, anticyclonic flow is found round the Crozet Plateau itself, with no more than 5?10{$\times$}106 m3 s?1 turning north to the east of the Crozet Islands. Circulation north of the Crozet Plateau, between the Plateau and the S-bend of the SAF, is extremely weak, fed only by anticyclonic meanders breaking off the SAF into the area from the west or north, and occasional input from the northward, partially wind-driven (i.e. Ekman) flow south and east of the islands. In consequence of the weak circulation, dissolved iron from the land or sediments of the Crozet Plateau and Islands can build up during the winter in the Polar Frontal Zone between Crozet and the SAF, which gives rise to an annual bloom in this area. Biological evidence from satellite images, and from phytoplankton and zooplankton distributions, supports the circulation pattern we develop. This pattern confirms that patchiness of productivity in the bloom area results from close juxtaposition of water that has entered the area from the west from the SAF and from the south and east after flowing past the islands. Flow from the south and east has had a chance to entrain iron from the islands and sediments whereas flow from the west has not.} } @article{soton40714, volume = {111}, number = {C5}, month = {May}, author = {Raymond Pollard and Paul Tr{\'e}guer and Jane Read}, title = {Quantifying nutrient supply to the Southern Ocean}, journal = {Journal of Geophysical Research}, pages = {C05011--[9pp]}, year = {2006}, keywords = {nutrient supply, southern ocean}, url = {https://eprints.soton.ac.uk/40714/}, abstract = {Using nutrient concentrations on neutral density surfaces in the Southern Ocean and climatological winds, both of which are fairly well constrained, we have estimated the long-term average of net export from the upper ocean (i.e., the net supply of nutrients in Circumpolar Deep Water and Antarctic Intermediate Water to the surface layer) over the whole of the Southern Ocean south of the wind stress maximum at an average latitude of 50?S. We calculate net new production (equivalent to export production) values of 51 {$\pm$} 3 Tmol Si yr{\ensuremath{<}}sup{\ensuremath{>}}-1{\ensuremath{<}}/sup{\ensuremath{>}} and 14 {$\pm$} 3 Tmol N yr{\ensuremath{<}}sup{\ensuremath{>}}-1{\ensuremath{<}}/sup{\ensuremath{>}}. The latter is equivalent to 1.1 {$\pm$} 0.2 Pg C yr{\ensuremath{<}}sup{\ensuremath{>}}-1{\ensuremath{<}}/sup{\ensuremath{>}} when scaled with the Redfield ratio of C to N. These values are in good agreement with recent observational and modeling estimates and are reasonably in line with inverse model calculations. Interpolating the high-quality data from meridional World Ocean Circulation Experiment sections onto the neutral density surfaces revealed remarkable constancy of nutrient concentrations at all longitudes and depths below about 340 {$\pm$} 100 m, which we call the surface-influenced depth. This indicates that isopycnic stirring by eddies in the Southern Ocean is efficient at homogenizing nutrient concentrations and removing any signature of remineralization. The large depth of the surface-influenced depth, over twice the winter mixed layer depth, also indicates that eddies must be responsible for transferring nutrient deficits resulting from drawdown in the surface layer across the pycnocline to several hundred meters deep.} } @article{soton49508, volume = {54}, number = {18-20}, title = {Real-time forecasting of ecosystem dynamics during the CROZEX experiment and the roles of light, iron, silicate, and circulation}, author = {E.E. Popova and R.T. Pollard and M.I. Lucas and H.J. Venables and T.R. Anderson}, year = {2007}, pages = {1966--1988}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Ecosystem modelling, Operational forecast, Primary productivity, Southern Ocean, Iron limitation}, url = {https://eprints.soton.ac.uk/49508/}, abstract = {Real-time coupled physical and biological forecasting was conducted prior to and during the CROZet natural bloom and EXport experiment (CROZEX) programme in the Southern Ocean (SO) between November 2004 and January 2005. The programme was aimed at investigating, through both measurements and modelling, the origin and fate of an intense and long-lasting phytoplankton bloom that is unusual for the otherwise high-nutrient low-chlorophyll conditions that characterise the SO. It was hypothesised that dissolved iron supplied to the system from shallow sediments accumulates downstream of the Crozet Islands during winter and creates conditions that favour phytoplankton production.{\ensuremath{<}}br/{\ensuremath{>}}Regular 14-day forecasts and reanalysis of the biogeochemical fields were issued on a weekly basis using a 3D primitive equation model coupled with an 11-component ecosystem model, along with assimilation of remotely sensed and in situ data. Real-time modelling assisted not only in optimisation of the cruise strategy, but also provided an ongoing synthesis of observations and test of the working hypotheses proposed to explain bloom dynamics in the study area.The model results indicated that a complex interplay between light, iron, and silicate limitation on primary production and grazing control determined the spatial extent and dynamics of the phytoplankton bloom. The model suggested that natural fertilisation of the area by dissolved iron was insufficient on its own to initiate a phytoplankton bloom. The persistence of deep mixing in the southern part of the iron-enriched waters was delaying, or in some areas preventing, the development of the bloom.} } @article{soton439266, volume = {84}, number = {2}, month = {December}, author = {Nathan Porath}, title = {The "Hikayat Patani": the kingdom of Patani in the Malay and Thai political world}, journal = {Journal of the Malay Branch of the Royal Asiatic Society}, pages = {45--65}, year = {2011}, keywords = {Patani Kingdom, Southern Thai History}, url = {https://eprints.soton.ac.uk/439266/}, abstract = {This paper looks at the Hikayat Patani as a mimetic text. It tries to capture Patani's power relations with neighbouring kingdoms. From the perspective of mimesis the text expresses similarity with Ayutthaya even as it describes the Patani sultan and sultana's rebellions against Ayutthaya. In relation to the surrounding Malay kingdoms and fiefdoms the text expresses Patani's superiority. In relation to Johor it fractures mimetic similarity Building upon previous works on the Hikayat Patani, this paper offers some interpretations of the text that have been overlooked by previous scholars.} } @article{soton7866, volume = {215}, title = {Effect of sperm concentration and sperm ageing on fertilisation success in the Antarctic soft-shelled clam Laternula elliptica and the Antarctic limpet Nacella concinna}, author = {D.K. Powell and P.A. Tyler and L.S. Peck}, year = {2001}, pages = {191--200}, journal = {Marine Ecology Progress Series}, keywords = {SPERM, FERTILIZATION, ANTARCTIC OCEAN, SOUTHERN OCEAN, LIMPETS, REPRODUCTION, BIOLOGY}, url = {https://eprints.soton.ac.uk/7866/} } @incollection{soton447545, booktitle = {The Palgrave Handbook of Cold War Literature}, editor = {Andrew Hammond}, month = {October}, title = {Gwebede?s Wars: Anglophone black novels in Southern Africa 1965-1989}, author = {Ranka Primorac and Stephen Chan}, publisher = {Palgrave Macmillan}, year = {2020}, keywords = {Africa, Cold War, Literature, Politics, Southern,}, url = {https://eprints.soton.ac.uk/447545/}, abstract = {The Cold War is often described in general terms as a single homogenous event, even though it had distinct ?hot? phases ? the Korean war of the 1950s and the Vietnam war of the 1960s and early 1970s, for example. There were points when the Cold War seemed on the verge of becoming thermonuclear, as in the case of the Cuban missile crisis in 1962. Metropolitan history routinely omits Africa as a site of superpower struggle. Yet Africa, from the dawn of decolonisation, was impacted by rivalry and manoeuvring for position on the part of the USA and the Soviet Union, with Chinese interventions also being a feature of the continent?s politics. Certainly, a period of intense violence and superpower intervention was inaugurated with Congo?s independence in 1960; it lasted until Southern Rhodesia?s Unilateral Declaration of Independence in 1965, when the level of conflict and violence escalated. For Africans all over the continent, and (arguably) particularly in its southern region, the era of decolonisation was marked by intense hope and expectation, as well as by senses of often acute crisis ? what Mbembe and Roitman describe, in a different context, as ?upheavals and tribulations, instabilities, fluctuations and ruptures of all sorts?. Literature registers the social and political uncertainties of this periods complexly and unevenly. This chapter selects for close consideration a set of novels that, in one way or another, address the topics of politics and war as their key concerns. Although anything like a full survey of how southern African cold-war politics relates to its literatures is next to impossible in a chapter of this length (in part because of a set of disciplinary limitations we touch on below), this chapter sets a scholarly precedent in its cross-disciplinary approach, as well as its combination of broad comparative coverage and precise analytical detail.} } @article{soton1365, volume = {19}, number = {3/4}, title = {Palaeoenvironment and taphonomy of dinosaur tracks in the Vectis Formation (Lower Cretaceous) of the Wessex sub-basin, southern England}, author = {J.D. Radley and M.J. Barker and I.C. Harding}, year = {1998}, pages = {471--487}, journal = {Cretaceous Research}, keywords = {Vectis Formation, Lower Cretaceous, southern England, dinosaur tracks, palaeoenvironments, taphonomy.}, url = {https://eprints.soton.ac.uk/1365/}, abstract = {Reptilian ichnofossils are documented from three levels within the coastal lagoonal Vectis Formation (Wealden Group, Lower Cretaceous) of the Wessex Sub-basin, southern England (coastal exposures of the Isle of Wight). Footprints attributable toIguanodonoccur in arenaceous, strongly trampled, marginal lagoonal deposits at the base of the formation, indicating relatively intense ornithopod activity. These were rapidly buried by influxes of terrestrial and lagoonal sediment. Poorly-preserved footcasts within the upper part of the Barnes High Sandstone Member are tentatively interpreted as undertracks. In the stratigraphically higher Shepherd's Chine Member, footcasts of a small to medium-sized theropod and a small ornithopod originally constituted two or more trackways and are preserved beneath a distinctive, laterally persistent bioclastic limestone bed, characterised by hypichnialDiplocraterion. These suggest relatively low rates of dinosaurian activity on a low salinity, periodically wetted mudflat. Trackway preservation in this case is due to storm-induced shoreward water movements which generated influxes of distinctive bioclastic lithologies from marginal and offshore lagoonal settings. The rapidly-deposited footprint-fills occasionally contain fully articulated shallow burrowing bivalves. {\ensuremath{<}}br/{\ensuremath{>}}} } @article{soton468925, volume = {126}, number = {2}, month = {February}, author = {Nithya Raghavan and Andre N Miller and Malcolm Gardner and Peter C FitzGerald and Anthony R Kerlavage and David A Johnston and Fred A Lewis and Matty Knight}, title = {Comparative gene analysis of Biomphalaria glabrata hemocytes pre- and post-exposure to miracidia of Schistosoma mansoni}, journal = {Molecular and Biochemical Parasitology}, pages = {181--91}, year = {2003}, keywords = {Amino Acid Sequence, Animals, Biomphalaria/enzymology, Blotting, Southern, Cell Line, Ciona intestinalis/enzymology, Expressed Sequence Tags, Hemocytes/parasitology, Molecular Sequence Data, RNA-Directed DNA Polymerase/chemistry, Reverse Transcriptase Polymerase Chain Reaction, Schistosoma mansoni/pathogenicity, Sequence Alignment, Sequence Homology, Amino Acid, Transcription, Genetic}, url = {https://eprints.soton.ac.uk/468925/}, abstract = {The internal defense mechanism of the snail Biomphalaria glabrata during a schistosome infection is activated and mediated via the immune effector cells known as hemocytes. Since resistance and susceptibility to schistosome infection is known to be genetically determined, our interest was to use the EST approach as a gene discovery tool to examine transcription profiles in hemocytes of resistant snails pre- and post-exposure to Schistosoma mansoni. Comparative analysis of the transcripts suggested that parasite exposure caused an active metabolic response in the hemocytes. The most abundant transcripts were those showing 23-74\% similarity to known reverse transcriptases (RT). Further characterization by RT-PCR indicated the RT transcripts were expressed in normal snails, parasite exposed snails, and the embryonic cell line Bge. To determine whether the occurrence of RT transcripts correlates to the presence of functional enzyme activity in the snails, RT assays were performed from both resistant and susceptible snails, pre- and post-exposure to miracidia, using protein extracts from the head-foot and posterior region tissues. Results indicated that in the resistant snail, RT activity was greater in the posterior region than in the head-foot. After exposure, however, RT activity increased dramatically in the head-foot, with peak activity at 24 h post-exposure. The detection of RT activity in B. glabrata was unexpected and the role of this enzyme in the hemocyte-mediated killing of parasites is not yet known. However, identification of this and other transcripts from these cells by the EST approach provides a useful resource towards elucidating the molecular basis of resistance/susceptibility in this snail-host parasite relationship.} } @article{soton433858, volume = {226}, month = {October}, title = {Drivers of mangrove distribution at the high-energy, wave-dominated, southern African range limit}, author = {Jacqueline L. Raw and Jasmin A. Godbold and Lara van Niekerk and Janine B. Adams}, year = {2019}, journal = {Estuarine, Coastal and Shelf Science}, keywords = {Biogeographic patterns, Climatic drivers, Estuaries, Geomorphological drivers, Southern Africa, Structural equation modelling}, url = {https://eprints.soton.ac.uk/433858/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Mangrove distribution patterns at regional scales are influenced by additional factors besides temperature and rainfall regimes. This study identified abiotic drivers of mangrove area cover along the high-energy, wave-dominated coastline of South Africa. This is one of the southernmost locations globally for mangroves. A structural equation model (SEM) was used to delineate relationships between multiple variables that represented climatic and geomorphological drivers of current mangrove distribution patterns. Floodplain area, inlet stability, and the flow regime of the estuary were identified as significant predictors of mangrove area. The results of this study confirm that for this region mangrove distribution is controlled by coastal topographical features and estuarine dynamics rather than temperature minima. This is similar to other high-energy, wave-dominated coasts of Australia, Brazil, and New Zealand. Future research should, therefore, incorporate regional-scale factors that restrict current distributions as they could inform on potential limitations to expansion, particularly for southern hemisphere range limits.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton49506, volume = {54}, number = {18-20}, title = {Sub-mesoscale structure and the development of an eddy in the Subantarctic Front north of the Crozet Islands}, author = {J.F. Read and R.T. Pollard and J.T. Allen}, year = {2007}, pages = {1930--1948}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Mesoscale features, Oceanic eddies, Ocean circulation, Algal bloom, Subantarctic Front, Southern Ocean, Indian Ocean, Polar Frontal Zone, 45?S, 50?E}, url = {https://eprints.soton.ac.uk/49506/}, abstract = {Two stations only 20 km apart were observed to have quite different biological and biogeochemical characteristics. The first site had low concentrations of chlorophyll and sufficient nutrients to support phytoplankton growth. The second site had high concentrations of chlorophyll, depleted nutrient concentrations and significant export of phytodetrital material had taken place. The two sites were located in the Polar Frontal Zone of the Southern Ocean to the northwest of the Crozet Islands. The main physical difference between the two sites was in the depth of the mixed layer. At the first site, the mixed layer was deep and well mixed, whereas the second site had a shallow, stratified layer; otherwise the horizontal gradients of physical properties were weak. Survey data from the surrounding area showed that the productive site was located on the edge of a filament of water drawn into a developing meander of the Subantarctic Front. Remotely sensed data provided a history of the growth of the meander in the Subantarctic Front and its development into an eddy in the Polar Frontal Zone. The dynamics associated with the filament in the meander were clearly important in driving the primary productivity, as an intrusion of saline water into adjacent fresher water generated a shallow mixed layer and conditions suitable for phytoplankton growth. The dynamics promoting conditions favourable to phytoplankton growth continued to operate as chlorophyll was enhanced in the eddy after the main bloom had died away. Later measurements suggested that the surface layer had changed from diatom dominated to a coccolithophore or calcite-rich community.} } @article{soton354007, volume = {81}, month = {November}, title = {Plasticity in shell morphology and growth among deep-sea protobranch bivalves of the genus Yoldiella (Yoldiidae) from contrasting Southern Ocean regions}, author = {Adam Reed and J.P. Morris and K. Linse and S. Thatje}, year = {2013}, pages = {14--24}, journal = {Deep Sea Research Part I: Oceanographic Research Papers}, keywords = {antarctic, bivalve, plasticity, growth, morphology, southern ocean}, url = {https://eprints.soton.ac.uk/354007/}, abstract = {The ecology of Antarctic deep-sea fauna is poorly understood and few studies have gone beyond assessing biodiversity when comparing deep regions of the Southern Ocean. Protobranch bivalves are ubiquitous in the deep ocean and are widely distributed in the Southern Ocean. This paper examines the potential responses to environmental differences in the common protobranchs Yoldiella valettei, Yoldiella ecaudata, and Yoldiella sabrina from contrasting deep-sea environments of the Weddell Sea, Scotia Sea, Amundsen Sea, and South Atlantic. There are significant differences in morphology between deep-sea regions in all species and a significant difference in shell weight in Y. valettei between the Amundsen Sea and Weddell Seas. Growth rates of Y. valettei and Y. ecaudata in the Amundsen Sea are also higher than elsewhere and Y. valettei have heaviest shells in the Amundsen Sea, suggesting more favourable conditions for calcification and growth. The plasticity observed among deep-sea regions in the Southern Ocean is likely to be driven by different oceanographic influences affecting temperature and food fluxes to the benthos, and demonstrate the species? ability to differentially adapt between cold-stenothermal environments. This study suggests that subtle changes in the environment may lead to a divergence in the ecology of invertebrate populations and showcases the protobranch bivalves as a future model group for the study of speciation and radiation processes through cold-stenothermal environments.} } @article{soton469008, volume = {33}, number = {1}, month = {April}, author = {R. R. Reisinger and P. J.N. de Bruyn and C. A. Tosh and W. C. Oosthuizen and N. T. Mufanadzo and M. N. Bester}, title = {Prey and seasonal abundance of killer whales at sub-Antarctic Marion Island}, journal = {African Journal of Marine Science}, pages = {99--105}, year = {2011}, keywords = {Diet, Foraging, Orcinus orca, Seals, Seasonal occurrence, Southern ocean}, url = {https://eprints.soton.ac.uk/469008/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}The diet of killer whales Orcinus orca was investigated from 48 predation events observed during 823 sightings at sub-Antarctic Marion Island between 2006 and 2009. From these events, there were 10 cases where prey could be identified. Killer whales fed on fur seals Arctocephalus tropicalis, elephant seals Mirounga leonina and penguins. Constant effort (dedicated) observations (259 hours, 2008-2009) showed that the peak in killer whale abundance was between September and December with a secondary peak between April and May, which coincided with peaks in the abundance of seals and penguins.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton469010, volume = {33}, number = {9}, title = {Long distance breeding dispersal of a southern elephant seal}, author = {Ryan R. Reisinger and Marth{\'a}n N. Bester}, year = {2010}, pages = {1289--1291}, journal = {Polar Biology}, keywords = {Emigration, Gene flow, Gough Island, Marion Island, Mirounga leonina, Movement, Natal dispersal, Southern Ocean}, url = {https://eprints.soton.ac.uk/469010/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Southern elephant seals range extensively during regular foraging excursions. Despite this they are highly philopatric and long range dispersal is rare. At Gough Island, southern Atlantic Ocean, we observed a breeding adult male elephant seal during September 2009, which had been tagged on its natal beach at Marion Island, southern Indian Ocean, in November 1998. The individual was resighted only once on Marion Island, 6 months after tagging. This 3,860 km movement represents dispersal (and likely gene flow) between distinct populations from different elephant seal geographical provinces. Given the polygynous breeding system of this species, the presence of this single male may have a disproportionate genetic effect on the small number of southern elephant seals breeding at Gough Island.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton455442, volume = {37}, number = {1}, month = {April}, title = {Overlap and temporal variation in the diets of sympatric Antarctic and Subantarctic fur seals ({\ensuremath{<}}i{\ensuremath{>}}Arctocephalus spp.{\ensuremath{<}}/i{\ensuremath{>}}) at Marion Island, Prince Edward Islands}, author = {Ryan R. Reisinger and Marietjie Landman and Nonkoliso Mgibantaka and Malcolm J. Smale and Marth{\'a}n N. Bester and P. J.Nico De Bruyn and Pierre A. Pistorius}, year = {2018}, journal = {Polar Research}, keywords = {foraging, marine mammal, pinniped, Prey, scats, Southern Ocean}, url = {https://eprints.soton.ac.uk/455442/}, abstract = {Antarctic ({\ensuremath{<}}i{\ensuremath{>}}Arctocephalus gazella{\ensuremath{<}}/i{\ensuremath{>}}) and Subantarctic ({\ensuremath{<}}i{\ensuremath{>}}A. tropicalis{\ensuremath{<}}/i{\ensuremath{>}}) fur seals are important predators in the Southern Ocean. Marion Island (southern Indian Ocean) hosts the largest sympatric breeding populations of these two species. Environmental and population changes here over two decades may have influenced their diet and trophic interactions. To quantify diet, we analysed prey remains in scat samples from Antarctic (661 scats) and Subantarctic (750 scats) fur seals collected at Marion Island (2006?2010). We assessed diet composition over time and calculated dietary overlap. The diet of both species was dominated by fish prey (98.2\% and 99.4\% of prey items), mainly myctophids. Antarctic fur seals consumed small numbers of penguins, cephalopods and crustaceans. In Subantarctic fur seal scats, crustaceans and cephalopods were rare and penguin remains were absent. The diets of the two species overlapped substantially (Pianka?s index = 0.98), however, small but significant differences in the relative proportions of prey were evident. Seasonal and annual diet changes suggest that their diet is similarly influenced by patterns of local prey availability and abundance. Despite substantial changes in the population size and trajectory of Antarctic and Subantarctic fur seals ? which would be expected to influence trophic interactions between them ? comparing our data to those from earlier studies (1989?2000) did not reveal significant long-term dietary changes in either species.} } @article{soton469013, volume = {33}, number = {4}, month = {April}, author = {Ryan R. Reisinger and Trevor McIntyre and Marth{\'a}n N. Bester}, title = {Goose barnacles hitchhike on satellite-tracked southern elephant seals}, journal = {Polar Biology}, pages = {561--564}, year = {2010}, keywords = {Lepas australis, Southern elephant seal, Southern Ocean, Species transport}, url = {https://eprints.soton.ac.uk/469013/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Goose barnacles (Lepas australis) attached to satellite-relay data loggers were carried by three southern elephant seals (Mirounga leonina) from Marion Island. Their movements across the Polar Frontal Zone are presented, providing further evidence that megafauna are potential vectors for the transport of species into the Southern Ocean.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton469006, volume = {12}, number = {2}, author = {Ryan R. Reisinger and P. J.N. de Bruyn and Marth{\'a}n N. Bester}, note = {Copyright: Copyright 2012 Elsevier B.V., All rights reserved.}, title = {Abundance estimates of killer whales at subantarctic Marion Island}, journal = {Aquatic Biology}, pages = {177--185}, year = {2011}, keywords = {Count, Mark-recapture, Orcinus orca, Photo-identification, Population size, Southern ocean}, url = {https://eprints.soton.ac.uk/469006/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Killer whales Orcinus orca are apex predators known to have important effects on marine ecosystems. A fundamental step towards understanding their role in ecosystems, and vital for their informed management and conservation, is the rigorous estimation of their abundance. Studies concerning this species have used mark-recapture analytical techniques to estimate abundance, but enumeration of identifiable individuals is more common. This study estimated the abundance of killer whales occurring inshore at subantarctic Marion Island. Mark-recapture analyses were performed using nearly 10 000 photographs taken from 2006 to 2009. Using careful quality control criteria, we identified 37 ind. The evident capture heterogeneity violates the underlying assumptions of the open population POPAN parameterization in the software program MARK we initially used. We thus used the simpler Chapman modified Lincoln-Petersen estimator, calculating a population size of 37 ind. (95\% CI = 29 to 44) for the period 2006 to 2007 and 32 ind. (95\% CI = 30 to 33) for 2007 to 2008. Both estimates are close to the catalogue size, suggesting that enumeration is an accurate measure of abundance in this study. Our results are comparable to recent abundance estimates for the neighbouring Crozet Archipelago ({\texttt{\char126}}1000 km due east). No rigorous approach has been used previously to estimate the abundance of killer whales at Marion Island. This estimate provides a foundation for further research related to the sociality and potential ecological impact of this population of killer whales in the Southern Ocean.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton41430, volume = {93}, number = {2-4}, title = {The influence of UV irradiation on the photoreduction of iron in the Southern Ocean}, author = {M.J.A. Rijkenberg and A.C. Fischer and J.J. Kroon and L.J.A. Gerringa and K.R. Timmermans and H.Th. Wolterbeek and H.J.W. de Baar}, year = {2005}, pages = {119--129}, journal = {Marine Chemistry}, keywords = {iron, photoreduction, UV, Southern Ocean, EisenEx}, url = {https://eprints.soton.ac.uk/41430/}, abstract = {An iron enrichment experiment, EisenEx, was performed in the Atlantic sector of the Southern Ocean during the Antarctic spring of 2000. Deck incubations of open ocean water were performed to investigate the influence of ultraviolet B (UVB: 280-315 nm) and ultraviolet A (UVA: 315-400 nm) on the speciation of iron in seawater, using an addition of the radioisotopes Fe-59(III) (1.25 nM) or Fe-55(III) (0.5 nM). Seawater was sampled inside and outside the iron-enriched region. The radioisotopic Fe(II) concentration was monitored during daylight under three different light conditions: the full solar spectrum (total), total minus UVB, and total minus UVB+UVA. A distinct diel cycle was observed with a clear distinction between the three different light regimes. A clear linear relationship was found for the concentration of radioisotopic Fe(II) versus irradiance. UVB produced most of the Fe(II) followed by UVA and visible light (VIS: 400-700 nm), respectively. UVB produced 4.89 and 0.69 pM m(2) W-1 radioisotopic Fe(II) followed by UVA with 0.33 and 0.10 pM M-2 W-1 radioisotopic Fe(II) and VIS with 0.04 and 0.03 pM m(2) W-1 radioisotopic Fe(II).} } @article{soton41433, volume = {70}, number = {11}, month = {June}, author = {Micha J.A. Rijkenberg and Loes J.A. Gerringa and Vicky E. Carolus and Ilona Velzeboer and Hein J.W. de Baar}, title = {Enhancement and inhibition of iron photoreduction by individual ligands in open ocean seawater}, journal = {Geochimica et Cosmochimica Acta}, pages = {2790--2805}, year = {2006}, keywords = {diatom thalassiosira-weissflogii, cathodic stripping voltammetry, thiol-containing compounds, equatorial pacific-ocean, natural organic-ligands, open southern-ocean, atlantic-ocean, dissolved iron, inositol hexaphosphate, siderophore production}, url = {https://eprints.soton.ac.uk/41433/}, abstract = {In laboratory experiments, we investigated the effect of five individual Fe-binding ligands: phaeophytin, ferrichrome, desferrioxamine B (DFOB), inositol hexaphosphate (phytic acid), and protoporphyrin IX (PPIX) on the Fe(II) photoproduction using seawater of the open Southern Ocean. Addition of 10-100 nM Fe(III) to open Southern Ocean seawater without the model ligands and containing; 1.1 nM dissolved Fe(III), 1.75 +/- 0.28 equivalents of nM Fe of natural ligands with a conditional stability constant (log K) of 21.75 +/- 0.34 and a concentration DOC of 86.8 +/- 1.13 M C leads to the formation of amorphous Fe(III) hydroxides. These amorphous Fe(III) hydroxides are the major source for the photoproduction of Fe(II). The addition of the model ligands changed the Fe(II) photoproduction considerably and in various ways. Phaeophytin showed higher Fe(II) photoproduction than ferrichrome and the control, i.e., amorphous Fe(III) hydroxides. Additions of phytic acid between 65 and 105 nM increased the concentration of photoproduced Fe(II) with 0.16 nM Fe(II) per nM phytic acid, presumably due to the co-aggregation of Fe(III) and phytic acid leading via an increasing colloidal surface to an increasing photoreducible Fe(III) fraction. DFOB and PPIX strongly decreased the photoproduced Fe(II) concentration. The low Fe(II) photoproduction with DFOB confirmed reported observations that Fe(III) complexed to DFOB is photo-stable. The PPIX hardly binds Fe(III) in the open Southern Ocean seawater but decreased the photoproduced Fe(II) concentration by complexing the Fe(II) with a binding rate constant of k(Fe(II)PPIX) = 1.04 x 10(-4) 1.53 x 10(-5) s(-1) nM(-1) PPIX. Subsequently, PPIX is suggested to act as a photo sensitizing producer of superoxide, thus increasing the dark reduction of Fe(III) to Fe(II). Our research shows that the photochemistry of Fe(III) and the resulting photoproduced Fe(II) concentration is strongly depending on the identity of the Fe-binding organic ligands and that a translation to natural conditions is not possible without further characterization of the natural occurring ligands.} } @article{soton50855, volume = {109}, number = {1-2}, month = {February}, author = {Micha J.A. Rijkenberg and Loes J.A. Gerringa and Klaas R. Timmermans and Astrid C. Fischer and Koos J. Kroon and Anita G.J. Buma and Bert Th. Wolterbeek and Hein J.W. de Baar}, title = {Enhancement of the reactive iron pool by marine diatoms}, journal = {Marine Chemistry}, pages = {29--44}, year = {2008}, keywords = {photoreduction, phytoplankton, diatoms, iron limitation, bioavailability, climate change, southern ocean}, url = {https://eprints.soton.ac.uk/50855/}, abstract = {Short term (2 days) laboratory experiments were performed to study the change in irradiance induced production of Fe(II) in{\ensuremath{<}}br/{\ensuremath{>}}seawater in the presence of two open oceanic Southern Ocean diatom species, Thalassiosira sp. and Chaetoceros brevis. Three irradiance conditions were applied: 1) UVB+UVA+VIS, 2) UVA+VIS, and 3) VIS, and Fe concentrations of 0 and 5 nM Fe were added to natural Southern Ocean seawater (containing 0.32 nM dissolved Fe and 1.69 equivalents of nM L?1 Fe dissolved organic ligands, log K?=22.03). The photoproduced concentration of Fe(II) showed no relationship with the concentration of total dissolved Fe or the concentration of strongly chelated iron. During incubations with the diatoms an increase in the Fe(II) concentration during the second day suggested a modification of the Fe speciation. In the presence of Thalassiosira sp. photoreduction of Fe(III) was observed, whereas in the presence of C. brevis irradiance independent Fe(III) reduction played an important role in the Fe(II) production. Furthermore, a decrease in the strongly chelated Fe concentration, in concert with a decrease in the conditional stability constant, suggested a modification of the strongly chelated Fe fraction in the experiments with C. brevis. The chelated Fe fraction did not change in cultures with Thalassiosira sp. Overall, the presence of diatoms appeared to{\ensuremath{<}}br/{\ensuremath{>}}enhance the reactive Fe pool improving the biological availability of Fe.} } @article{soton354675, volume = {2754}, month = {February}, title = {A revision of the Pyura stolonifera species complex (Tunicata, Ascidiacea), with a description of a new species from Australia}, author = {Marc Rius and Peter R. Teske}, year = {2011}, pages = {27--40}, journal = {Zootaxa}, keywords = {pyuridae, pyura dalbyin. sp., ascidian, taxonomy, pyura herdmani, pyura praeputialis, disjunct distribution, southern africa, chile, morocco}, url = {https://eprints.soton.ac.uk/354675/}, abstract = {Pyura stolonifera is a large solitary ascidian found in Africa, Australasia and South America. The taxonomic status of different populations of this species is disputed, especially since there is evidence for several distinct morphological and genetic units that point towards the existence of multiple cryptic species. While some researchers still recognize P. stolonifera as a single species, others treat the different populations as distinct species. Here, we present a revision of the P. stolonifera species complex based on the examination of samples from all regions where there are reliable reports of this taxon. We recognize four species that are both morphologically and genetically distinct, one of which is new to science and is formally described here. This species is morphologically distinct from the other three members of the species complex in terms of the colour and texture of the tunic, the arrangement of the gonads within the gut and the shape of the dorsal tubercle, among other characters. We name the new species Pyura dalbyi after Dr. J.E. Dalby Jr., whose research on its ecology and distribution provided the incentive for examining this species more closely.} } @article{soton364276, volume = {41}, number = {7}, month = {April}, author = {J. Robinson and E.E. Popova and A. Yool and M. Srokosz and R.S. Lampitt and J.R. Blundell}, title = {How deep is deep enough? Ocean iron fertilization and carbon sequestration in the Southern Ocean}, journal = {Geophysical Research Letters}, pages = {2489--2495}, year = {2014}, keywords = {ocean iron fertilization, Lagrangian particle tracking, deep circulation, Southern Ocean}, url = {https://eprints.soton.ac.uk/364276/}, abstract = {Artificial ocean iron fertilization (OIF) enhances phytoplankton productivity and is being explored as a means of sequestering anthropogenic carbon within the deep ocean. To be considered successful, carbon should be exported from the surface ocean and isolated from the atmosphere for an extended period (e.g., the Intergovernmental Panel on Climate Change's standard 100 year time horizon). This study assesses the impact of deep circulation on carbon sequestered by OIF in the Southern Ocean, a high-nutrient low-chlorophyll region known to be iron stressed. A Lagrangian particle-tracking approach is employed to analyze water mass trajectories over a 100 year simulation. By the end of the experiment, for a sequestration depth of 1000 m, 66\% of the carbon had been reexposed to the atmosphere, taking an average of 37.8 years. Upwelling occurs predominately within the Antarctic Circumpolar Current due to Ekman suction and topography. These results emphasize that successful OIF is dependent on the physical circulation, as well as the biogeochemistry.} } @incollection{soton34290, booktitle = {WFS comparative studies: cross-national summaries (World Fertility Surveys)}, month = {May}, title = {A comparative analysis of determinants of birth intervals}, author = {G. Rodriguez and J. Hobcraft and J. McDonald and J. Menken and J. Trussell}, publisher = {International Statistical Institute}, year = {1984}, pages = {31pp.}, keywords = {Korea, Bangladesh, Indonesia, Sri Lanka, Colombia, Jamaica, Jordan, Kenya, Mexico, Asia, Eastern Asia, Southern Asia, South America, Caribbean, Central America, birth intervals, fertility measurements, measurement, models, ethical research methodology, birth order, family characteristics, family and household, age factors, population characteristics, population educational status, sex preference, ideal family size, developed countries Asia, developing countries South America, Northern Latin America, Americas, Middle East, Africa, Eastern Africa, South of the Sahara, North America, fertility, population dynamics, demographic factors, family relationships, socioeconomic status, socioeconomic factors, economic factors, value orientation, psychological factors, behavior, family size}, url = {https://eprints.soton.ac.uk/34290/}, abstract = {The life-table approach is particularly appropriate to the analysis of birth intervals because a major pitfall of measurement can be avoided. If only intervals beginning with the birth of 1 child and ending with the next birth are considered, there is a major bias in any results because all information is omitted for women who stopped childbearing within that interval -- those who never had a subsequent birth or, in the case of data obtained from surveys, those whose reproductive histories may be incomplete at the time of the interview. New methods have become available that permit simultaneous analysis of life tables according to several covariates and produce more readily interpretable summary and comparative statistics. It is important to develop efficient ways of determining which hazard models are most likely to describe a particular data set well, so that exact estimation procedures are applied to only a small number of candidates for the final model. Thus, this discussion of the birth interval analysis is conducted in 2 parts: screening and final estimation. This is preceded by a brief discussion of the information used in the analysis. The decision was made to work with the 9 countries used by Hobcraft and Casterline (1983) and again by Gilks (1982) in his work on birth intervals. These include: Bangladesh, Colombia, Indonesia, Jamaica, Jordan, Kenya, Korea, Mexico, and Sri Lanka. The advantages of comparability with other work outweighed the marginal benefits of choosing a set of countries with optimal variability in terms of patterns of birth interval distributions. Even after controlling for all the factors in the final model, the adjusted quintums showed large variations between subgroups. For age at start of the interval, the differences in the adjusted quintums between the youngest and oldest groups was in excess of 0.2 for all countries except Kenya and, marginally, Jordan and was around 0.3 for Korea, Mexico, and Sri Lanka. At the other extreme differences between adjusted quintums by birth order exceeded 0.05 only for Korea, which had a large range of 0.20. These findings suggest that age is of far greater importance in determining fertility behavior than is birth order, even where there is known to be substantial fertility control, although Korea is a striking exception. A partial explanation of the unusual pattern of Korea is the impact of sex preference.} } @article{soton27821, volume = {109}, number = {F2}, title = {The cross-sectional shape of tidal sandbanks: modeling and observations}, author = {Pieter C. Roos and Suzanne J.M.H. Hulscher and Michiel A.F. Knaapen and Ruud M.J. Van Damme}, year = {2004}, pages = {F02003}, journal = {Journal of Geophysical Research}, keywords = {morphodynamics, tidal sandbanks, equilibrium profiles, southern North Sea, connected sand ridges, dynamics, banks, transport, bed, waves}, url = {https://eprints.soton.ac.uk/27821/}, abstract = {To improve our understanding of tidal sandbank dynamics, we have developed a nonlinear morphodynamic model. A crucial property of the model is that it fully resolves the dynamics on the fast ( tidal) timescale, allowing for asymmetric tidal flow with an M-0, M-2, and M-4 component. This approach, extending earlier research on the formation of tidal sandbanks, leads to equilibrium profiles. Their heights ( 60 - 90\% of the water depth) and shapes are controlled by the mode of sediment transport and the hydrodynamic conditions. Bed load transport under symmetrical tidal conditions leads to high spiky banks. Several mechanisms tend to lower and smooth these profiles, such as the relaxation of suspended sediment, wind wave stirring, and tidal asymmetry. This last causes the profiles to be asymmetric, as well. The morphodynamic equilibrium expresses a tidally averaged balance between a destabilizing flux due to fluid drag and the downslope transport induced by both tidal flow and wind wave stirring. The modeled profiles are in fair agreement with observations from the North Sea.} } @article{soton49520, volume = {54}, number = {18-20}, title = {Estimating carbon, silica and diatom export from a naturally fertilised phytoplankton bloom in the Southern Ocean using PELAGRA: a novel drifting sediment trap}, author = {I. Salter and R.S. Lampitt and R. Sanders and A. Poulton and A.E.S. Kemp and B. Boorman and K. Saw and R. Pearce}, year = {2007}, pages = {2233--2259}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {PELAGRA, Diatom flux, Eucampia antarctica, POC export, Iron-fertilisation, Southern Ocean}, url = {https://eprints.soton.ac.uk/49520/}, abstract = {During the austral summer of 2004?2005, a large multi-disciplinary research cruise investigated the development and fate of a naturally iron-fertilised phytoplankton bloom in the Southern Ocean (Crozet Plateau). As part of this extensive process study, a neutrally buoyant sediment trap (PELAGRA) was deployed to constrain the magnitude, composition, and variability of upper-ocean particle export. In the productive regime north of the plateau we observed depth-normalised (100-m) organic carbon fluxes between 11 and 440 mg C m?2 d?1, and in the HNLC control region to the south similarly normalised fluxes between 28 and 46 mg C m?2 d?1. Mass balance calculations indicate that the high levels of carbon export north of the plateau would need to be maintained for at least 30 days in order to account for estimated seasonal depletion of dissolved silicic acid in surface waters. This would imply that the flux of organic carbon is ?15 g C m?2 for the period of the bloom north of the plateau. A range of export ratios (proportion of surface production lost to downward flux) was calculated using both contemporaneous and retrospective estimates of integrated production, and these highlight the temporal decoupling between production and export. Calculated export ratios were at their highest north of the plateau and correlate strongly with the selective export of large, heavily silicified diatoms, particularly Eucampia antarctica, relative to the surface community structure. By normalising the molar elemental ratios measured in the exported particles to the molar elemental ratios of the upper-ocean particle field we also observed a strong decoupling of Si:C and Si:N. This suggests that the decoupling of the global silica and carbon cycles, which is well known as a defining feature of the Southern Ocean, has its origins in the upper ocean.} } @article{soton7939, volume = {46}, number = {1}, title = {Nutrients and chlorophyll at two sites in the Thames plume and southern North Sea}, author = {R. Sanders and T. Jickells and D. Mills}, year = {2001}, pages = {13--28}, journal = {Journal of Sea Research}, keywords = {NUTRIENTS, THAMES PLUME, ESTUARIES, PHYTOPLANKTON, CHLOROPHYLL, SILICATE, PHOSPHATE, SOUTHERN NORTH SEA}, url = {https://eprints.soton.ac.uk/7939/}, abstract = {The Thames plume is a moderately turbid (suspended load up to 80 mg dm?3), high nutrient (summer NO3? concentrations \>10 M, summer PO43? concentrations \>2.5 M) and well-mixed aquatic ecosystem which connects the Thames estuary to the southern North Sea. Six cruises were undertaken to investigate the response of an inshore site in this system to these high nutrient levels via a comparison with a site in the seasonally nutrient-depleted southern North Sea. The seasonal cycle of chlorophyll concentrations in both environments was similar, consisting of higher chlorophyll a levels in spring than in summer. A spring bloom of diatoms occurs in both environments; in the plume it is succeeded by low chlorophyll levels and a diatom-dominated community at low silicate levels and at the offshore site by a non-siliceous community at similar silicate levels. The low summer chlorophyll levels and diatom dominance, which occur at the inshore site despite an abundance of nitrate and phosphate may be due to a simultaneous inhibition of non-siliceous growth and silicate limitation of diatom growth. We hypothesise that this is caused by the high turbidity at the inshore site reducing water column light levels such that they become adequate for diatom growth but inadequate for non-siliceous growth; however, we have inadequate data to confirm this suggestion. The benthic silicate flux cannot support the inferred diatom silicate requirement at the inshore site suggesting that silicate mineralisation in the water column may occur and control diatom growth. Nutrient/salinity plots suggest that the net effect of this complex biogeochemistry is a semi-conservative transport of NO3? and PO43? through the plume to the offshore region.} } @article{soton49518, volume = {54}, number = {18-20}, title = {New production and the f ratio around the Crozet Plateau in austral summer 2004?2005 diagnosed from seasonal changes in inorganic nutrient levels}, author = {R. Sanders and P.J. Morris and M. Stinchcombe and S. Seeyave and H. Venables and M. Lucas}, year = {2007}, pages = {2191--2207}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {CROZEX, Southern Ocean, New production, Export production, Nitrate, Chlorophyll}, url = {https://eprints.soton.ac.uk/49518/}, abstract = {Recent mesoscale iron-fertilisation experiments suggest that iron may be an important micronutrient in HNLC regions but estimates of carbon export from such experiments are inconclusive. An alternative strategy to estimate export from such environments is to observe naturally productive ecosystems associated with topography. One such system is the Crozet islands and associated plateau (Crozet), at 46?S, 52?E. Each year a large bloom of phytoplankton occurs to the north of Crozet with a reduced bloom occurring to the south. We use nitrate data from the Crozet region collected during austral summer 2004?2005 to estimate new production (NP) via the Redfield ratio. Peak integrated values of up to 50 g C m?2 to the north of the plateau and up to 15 g C m?2 to the south are inferred. We estimate total integrated primary production (TP) using satellite techniques and calculate f for each station. Overall NP is linearly related to TP. However, f declines at very high levels of TP because nitrate usage ceases despite continuing PP and because nitrate levels increased from their postbloom low. This results either from a resupply of nitrate from beneath the thermocline due to mixing processes or to the mixed-layer ammonification and nitrification of accumulated organic nitrogen. We discount the first possibility because our estimates of the mixing flux of nitrate appear to be inadequate to cause the entire recovery in nitrate levels, and because any mixing flux of nitrate would likely be accompanied by a resupply of iron, which would induce NP to occur and erode the resupply of nitrate. Instead we consider the recycling of accumulated organic nitrogen to be a more likely explanation based on our observation of high organic nitrogen levels in the mixed layer north of Crozet during the cruise. The implications of this conclusion are that euphotic zone nitrification is a significant process, and that in this system new and export production are not equivalent. This recycling is sufficiently large that it reduces our estimate of NP north of the plateau to a level where it is equivalent to NP in the south. Whether a similar refertilisation of the mixed layer occurred in the south of the study region, which would be consistent with a meridional gradient in carbon export, is unknown due to the limited duration of the shipboard programme.} } @article{soton377475, volume = {504}, month = {May}, title = {East Weddell Sea echinoids from the JR275 expedition}, author = {Thomas Sauc{\`e}de and Huw Griffiths and Camille Moreau and Jennifer A. Jackson and Chester Sands and Rachel Downey and Adam Reed and Melanie Mackenzie and Paul Geissler and Katrin Linse}, year = {2015}, pages = {1--10}, journal = {ZooKeys}, keywords = {Echinoidea, Southern Ocean, Biodiversity}, url = {https://eprints.soton.ac.uk/377475/}, abstract = {Information regarding the echinoids in this dataset is based on the Agassiz Trawl (AGT) and epibenthic sledge (EBS) samples collected during the British Antarctic Survey cruise JR275 on the RRS James Clark Ross in the austral summer 2012. A total of 56 (1 at the South Orkneys and 55 in the Eastern Weddell Sea) Agassiz Trawl and 18 (2 at the South Orkneys and 16 in the Eastern Weddell Sea) epibenthic sledge deployments were performed at depths ranging from {\texttt{\char126}}280 to {\texttt{\char126}}2060 m. This presents a unique collection for the Antarctic benthic biodiversity assessment of an important group of benthic invertebrates. In total 487 specimens belonging to six families, 15 genera, and 22 morphospecies were collected. The species richness per station varied between one and six. Total species richness represents 27\% of the 82 echinoid species ever recorded in the Southern Ocean (David et al. 2005b, Pierrat et al. 2012, Sauc{\`e}de et al. 2014). The Cidaridae (sub-family Ctenocidarinae) and Schizasteridae are the two most speciose families in the dataset. They comprise seven and nine species respectively. This is illustrative of the overall pattern of echinoid diversity in the Southern Ocean where 65\% of Antarctic species belong to the families Schizasteridae and Cidaridae (Pierrat et al. 2012).} } @article{soton478107, volume = {34}, number = {8}, month = {October}, author = {Robert G. Scaife and Antony J. Long and Alistair J. Monteath and Paul D.M. Hughes and Michael J. Bentley and Philip Stone}, note = {Funding Information: The Hooker's Point sequence, in conjunction with Holocene pollen records (Barrow,; Turney et al.,; and Thomas et al.,), show that the Falkland Islands have remained treeless for a least the last c. 16 500 years. The landscape of the Falkland Islands is, therefore, an unusual example of a maritime environment that has developed without trees and higher shrubs. This rare environmental history provides an interesting ecological control site that may be used for the study of fluvial development under temperate, treeless, conditions. Peatlands in the Falkland Islands have previously been considered to be relic systems that formed during wetter conditions in the past (Otley et al.,). However, continued organic accumulation at Hooker's Point throughout the Late-glacial demonstrates that Falkland Island peatlands have developed under dry conditions in the past, and may continue to do so today. This finding suggests that some peatlands in marginal environments can remain valuable carbon sinks even under low precipitation regimes. The vegetation of Hooker's Point appears insensitive to the regional cooling during the ACR, but shifted toward a dwarf shrub-dominated community during the latter half of the Younger Dryas time period and Southern Hemisphere Early Holocene Thermal Maximum. The decline of tussac grass dominance under warming has implications for future vegetation communities in the Falkland Islands which are expected to be subjected to a warmer climate. The first appearance of long-distance Nothofagus pollen in the Hooker's Point sequence c. 13 330 cal a bp is likely to be wind-dependant, and occurs late in the ACR. This time period is associated with changes in the strength and/or position of the Southern Westerly Wind Belt, and shifts in wind proxies in Laguna Potrok Aike (Mayr et al.,) and Tierra del Fuego (Mansilla et al.,) closely overlap the Nothofagus pollen record from Hooker's Point. Acknowledgements. We thank the Shackleton Scholarship Fund for a grant to enable fieldwork in the islands, as well as NE/1022981/1. We are grateful to the Falkland Islands Department of Mineral Resources who provided project support. Alex Blake assisted in sample collection from Hooker's Point. We would also like to thank Professor V. Jones (University College, London) who kindly examined diatoms from selected levels of the peat sequence. The comments of two anonymous reviews helped to improve the focus and clarity of this manuscript. Publisher Copyright: {\copyright} 2019 The Authors. Journal of Quaternary Science Published by John Wiley \& Sons Ltd.}, title = {The Falkland Islands? palaeoecological response to millennial-scale climate perturbations during the Pleistocene?Holocene transition: implications for future vegetation stability in the southern ocean islands}, year = {2019}, journal = {Journal of Quaternary Science}, pages = {609--620}, keywords = {Falkland Islands, island conservation, palaeoecology, peatland, Southern Westerly Wind Belt}, url = {https://eprints.soton.ac.uk/478107/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Oceanic island flora is vulnerable to future climate warming, which is likely to promote changes in vegetation composition, and invasion of non-native species. Sub-Antarctic islands are predicted to experience rapid warming during the next century; therefore, establishing trajectories of change in vegetation communities is essential for developing conservation strategies to preserve biological diversity. We present a Late-glacial-early Holocene (16 500?6450 cal a bp) palaeoecological record from Hooker's Point, Falkland Islands (Islas Malvinas), South Atlantic. This period spans the Pleistocene-Holocene transition, providing insight into biological responses to abrupt climate change. Pollen and plant macrofossil records appear insensitive to climatic cooling during the Late-glacial, but undergo rapid turnover in response to regional warming. The absence of trees throughout the Late-glacial-early Holocene enables the recognition of far-travelled pollen from southern South America. The first occurrence of Nothofagus (southern beech) may reflect changes in the strength and/or position of the Southern Westerly Wind Belt during the Late-glacial period. Peat inception and accumulation at Hooker's Point is likely to be promoted by the recalcitrant litter of wind-adapted flora. This recalcitrant litter helps to explain widespread peatland development in a comparatively dry environment, and suggests that wind-adapted peatlands can remain carbon sinks even under low precipitation regimes.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton49510, volume = {54}, number = {18-20}, title = {Phytoplankton productivity and community structure in the vicinity of the Crozet Plateau during austral summer 2004/2005}, author = {S. Seeyave and M.I. Lucas and C.M. Moore and A.J. Poulton}, year = {2007}, pages = {2020--2044}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Southern Ocean, Polar Frontal Zone (PFZ), Crozet Islands, Phytoplankton, Primary productivity, Iron limitation}, url = {https://eprints.soton.ac.uk/49510/}, abstract = {The CROZet natural iron bloom and EXport experiment (CROZEX) was carried out around the Crozet Plateau (Southern Ocean) in late austral spring-early summer 2004/2005. The primary aim of this study was to test the hypothesis that natural Fe fertilisation from the islands enhanced primary production to the north of the plateau, leading to elevated carbon export. During the 12-week shipboard study (November?January), size-fractionated chlorophyll-a (chl-a), primary productivity and phytoplankton pigments were determined at 20 stations around the Crozet Plateau, both inside and outside the expected bloom region. Satellite-derived chl-a data from August 2004 to April 2005 revealed that the cruise period covered the declining stage of a large phytoplankton bloom north of the Crozet Plateau. Productivity derived from satellite chl-a data showed a strong north?south gradient, with productivity reaching a maximum of 1.9 g C m?2 d?1 in the north (late October), 0.6 over the plateau (late March) and 0.4 in the south (early December). From November to early December, measured chl-a and productivity were still relatively high northwest of the plateau (54?74 mg chl-a m?2 and 0.5?1.1 g C m?2 d?1), the assemblage being dominated by Phaeocystis sp. and microplankton representing 50\% of total chl-a. Declining biomass and productivity to the northwest in mid-December was associated with a picoplankton (52\%) dominated community (19?38 mg chl-a m?2 and 0.1?0.4 g C m?2 d?1). In contrast, at the north eastern edge of the plateau, a mixed diatom/Phaeocystis dominated bloom (229 mg chl-a m?2 and 3 g C m?2 d?1) developed in mid-January. South of the plateau in the control high-nutrient low-chlorophyll (HNLC) region, biomass and productivity were always significantly lower, with only a small chl-a peak in December, and a community composed of microflagellates, cyanobacteria and some giant diatoms. Particulate organic carbon (POC):chl-a ratios provided physiological evidence for the impact of Fe fertilisation north of the plateau. The assimilation rate (i.e. integrated productivity normalised to integrated chl-a, ?P/?chl-a) did not show significant differences between the north and south, probably due to the late sampling period relative to the bloom peak. Overall, measurements of primary productivity during CROZEX supported the hypothesis of enhanced biomass and production due to natural iron enrichment of the region north of the Crozet Plateau, while south of the plateau, low biomass and productivity resulted primarily from Fe limitation.} } @article{soton43307, volume = {10}, number = {1}, month = {April}, author = {Dale Serjeantson}, title = {?Science is measurement'; ABMAP, a database of domestic animal bone measurements}, journal = {Environmental Archaeology}, pages = {95--103}, year = {2005}, keywords = {zooarchaeology, bone measurements, southern britain, prehistoric, historic}, url = {https://eprints.soton.ac.uk/43307/}, abstract = {A database of animal bone measurements, the Animal Bone Metrical Archive Project (ABMAP), is now available on the Web at http://ads.ahds.ac.uk/catalogue/specColl/abmap. The measurements can be downloaded and imported into a spreadsheet. They are of bones of domestic animals from the Neolithic to the 19 th century AD from assemblages in England, most from southern England. An example is given of the retrieval of measurements of cattle metacarpals and their application in a scatter diagram. The database is a resource for zooarchaeologists and others concerned with research into prehistoric and early historic domestic livestock and animal husbandry. {\ensuremath{<}}br/{\ensuremath{>}}} } @article{soton376616, volume = {42}, number = {9}, month = {May}, author = {K.L. Sheen and J.A. Brearley and A.C. Naveira Garabato and D.A. Smeed and L. St. Laurent and M.P. Meredith and A.M. Thurnherr and S.N. Waterman}, title = {Modification of turbulent dissipation rates by a deep Southern Ocean eddy}, journal = {Geophysical Research Letters}, pages = {3450--3457}, year = {2015}, keywords = {mixing, eddy, turbulent dissipation, internal waves, southern ocean, ray tracing}, url = {https://eprints.soton.ac.uk/376616/}, abstract = {The impact of a mesoscale eddy on the magnitude and spatial distribution of diapycnal ocean mixing is investigated using a set of hydrographic and microstructure measurements collected in the Southern Ocean. These data sampled a baroclinic, mid-depth eddy formed during the disintegration of a deep boundary current. Turbulent dissipation is suppressed within the eddy, but is elevated by up to an order of magnitude along the upper and lower eddy boundaries. A ray-tracing approximation is employed asa heuristic device to elucidate how the internal wave field evolves in the ambient velocity and stratification conditions accompanying the eddy. These calculations are consistent with the observations, suggesting reflection of internal wave energy from the eddy center and enhanced breaking through critical layer processes along the eddy boundaries. These results have important implications for understanding where and how internal wave energy is dissipated in the presence of energetic deep geostrophic flows.} } @article{soton429512, volume = {38}, number = {4}, month = {October}, author = {Yujing Shi and Shengjie Lai and Qiulan Chen and Di Mu and Yu Li and Xinxu Li and Wentvu Yin and Hongjie Yu}, title = {Analysis on the epidemiological features of human brucellosis in northern and southern areas of China, 2015-2016}, journal = {Chinese Journal of Endemiology}, pages = {435--440}, year = {2018}, keywords = {Bruceuosis, China, Epidemiology, Northern and southern}, url = {https://eprints.soton.ac.uk/429512/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Objective To analyze the epidemiological characteristics of human brucellosis in northern and southern areas of China, and to develop national strategies for bruceUosis prevention and control. Methods Individual data on human bruceUosis was collected from the National Notifiable Infectious Disease Reporting Information System to describe the situation of bruceUosis in China during 2015-2016. Epidemiological features of the disease in northern and southern areas of China were analyzed. Results A total of 104 125 cases were reported in mainland China during 2015-2016, with an average incidence rate as 3.81/100 000. The overall incidence rate from the northern provinces was 7.77/100 000 in 2016, a 18.6\% decrease from 2015 (9.55/100 000), whereas the incidence rate in the southern provinces was 0.27/100 000 in 2016, with an increase of 28.6\%\% than 0.21/100 000 in 2015. 90.0\% of the newly infected counties mainly distributed in southern China. As for the locations of reporting cases, most of them were in the same counties in the northern areas (52.3\%) while most cases in the southern areas (59.6\%) were imported from other counties. The median age of the cases was 48 (IQR: 38-58) years, with male-to-female ratios as 2.7 \# 1 in the north and 2.2 : 1 in the south. Majority of the cases were occupation-related, from both the northern (86.8\%) and southern (62.7\%) areas. Human brucellosis occurred every month throughout the year but with an obvious seasonal increase between March and July. Conclusions Different epidemiological features of human bruceUosis appeared in both northern and southern areas of China. The disease was seen endemic in the northern and dispersal in the southern provinces. Appropriate strategies for bruceUosis prevention and control should be developed, according to the diiferent epidemiological characteristics in the northern or southern areas.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton446395, volume = {554}, month = {January}, title = {Early deglacial CO2 release from the Sub-Antarctic Atlantic and Pacific oceans}, author = {R. Shuttleworth and H.C. Bostock and T.B. Chalk and E. Calvo and S.L. Jaccard and C. Pelejero and A. Garcia Martinez and G. Foster}, year = {2021}, note = {Funding Information: We would like to thank the captains, crew and scientists that were involved in collecting the cores used in this study, specifically captain Doug Monks and the crew of the RV Tangaroa who helped collect the TAN1106-28 core. The funding for the TAN1106 voyage was from the Coasts and Oceans Physical Resources program awarded to the National Institute of Water and Atmospheric Research, New Zealand (grant number COPR1703). We thank Bryn Taiapa and Geraldine Jacobsen (ANSTO) for additional radiocarbon data for core TAN1106-28, this work was funded by AINSE grant number ALNGRA15502 and Dr Samuel Toucanne (Ifremer) for providing a further radiocarbon date to improve the age modelling of the deglaciation. We also thank Andy Milton, Matt Cooper, and Megan Spencer as well as the rest of the Foster lab for laboratory assistance. This project was supported by the Natural Environment Research Council [NE/L002531/1] to R.S. and [NE/J021075/1] to G.L.F. Spanish Ministry of Science and Innovation [CGL2015-68194-R] to E.C. and C.P. S.L.J. acknowledges financial support from the Swiss National Science Foundation (SNSF grant PP00P2\_172915), and A.M.-G. acknowledges funding from the Max Planck Society. Funding Information: We would like to thank the captains, crew and scientists that were involved in collecting the cores used in this study, specifically captain Doug Monks and the crew of the RV Tangaroa who helped collect the TAN1106-28 core. The funding for the TAN1106 voyage was from the Coasts and Oceans Physical Resources program awarded to the National Institute of Water and Atmospheric Research , New Zealand (grant number COPR1703 ). We thank Bryn Taiapa and Geraldine Jacobsen (ANSTO) for additional radiocarbon data for core TAN1106-28, this work was funded by AINSE grant number ALNGRA15502 and Dr Samuel Toucanne (Ifremer) for providing a further radiocarbon date to improve the age modelling of the deglaciation. We also thank Andy Milton, Matt Cooper, and Megan Spencer as well as the rest of the Foster lab for laboratory assistance. This project was supported by the Natural Environment Research Council [ NE/L002531/1 ] to R.S. and [ NE/J021075/1 ] to G.L.F., Spanish Ministry of Science and Innovation [ CGL2015-68194-R ] to E.C. and C.P., S.L.J. acknowledges financial support from the Swiss National Science Foundation (SNSF grant PP00P2\_172915 ), and A.M.-G. acknowledges funding from the Max Planck Society . Publisher Copyright: {\copyright} 2020 Elsevier B.V.}, journal = {Earth and Planetary Science Letters}, keywords = {CO flux, Heinrich Stadial 1, Southern Ocean, Sub-Antarctic, boron isotopes, deglaciation}, url = {https://eprints.soton.ac.uk/446395/}, abstract = {Over the last deglaciation there were two transient intervals of pronounced atmospheric CO2 rise; Heinrich Stadial 1 (17.5-15 kyr) and the Younger Dryas (12.9-11.5 kyr). Leading hypotheses accounting for the increased accumulation of CO2 in the atmosphere at these times invoke deep ocean carbon being released from the Southern Ocean and an associated decline in the global efficiency of the biological carbon pump. Here we present new deglacial surface seawater pH and CO2sw records from the Sub-Antarctic regions of the Atlantic and Pacific oceans using boron isotopes measured on the planktic foraminifera Globigerina bulloides. These new data support the hypothesis that upwelling of carbon-rich water in the Sub-Antarctic occurred during Heinrich Stadial 1, and contributed to the initial increase in atmospheric CO2. The increase in CO2sw is coeval with a decline in biological productivity at both the Sub-Antarctic Atlantic and Pacific sites. However, there is no evidence for a significant outgassing of deep ocean carbon from the Sub-Antarctic during the rest of the deglacial, including the second period of atmospheric CO2 rise coeval with the Younger Dryas. This suggests that the second rapid increase in atmospheric CO2 is driven by processes operating elsewhere in the Southern Ocean, or another region.} } @misc{soton485726, volume = {10}, title = {Observing Antarctic Bottom Water in the Southern Ocean}, author = {Alessandro Silvano and Sarah Purkey and Arnold L. Gordon and Pasquale Castagno and Andrew Stewart and Stephen Rintoul and Annie Foppert and Kathryn L. Gunn and Laura Herraiz-Borreguero and Shigeru Aoki and Yoshihiro Nakayama and Alberto Naveira Garabato and Carl Spingys and Camille Akhoudas and Jean Baptiste Sallee and Casimir de Lavergne and Povl Abrahamsen and Andrew Meijers and Michael P. Meredith and Shenjie Zhou and Takeshi Tamura and Kaihe Yamazaki and Kay Ohshima and Pierpaolo Falco and Giorgio Budillon and Tore Hattermann and Markus A. Janout and Pedro Llanillo and Melissa Bowen and Elin Darelius and Svein {\O}sterhus and Keith Nicholls and Craig Stevens and Denise Fernandez and Laura Cimoli and Stanley S. Jacobs and Adele Morrison and Andy Hogg and Alexander Haumann and Ali Mashayek and Zhaomin Wang and Rodrigo Kerr and Guy D. Williams and Won Sang Lee}, year = {2023}, note = {Funding Information: The author(s) declare financial support was received for the research, authorship, and/or publication of this article. ASi acknowledges funding from NERC (NE/V014285/1). MB, CSt, and DF acknowledge funding from the New Zealand Strategic Science Investment Fund: Antarctic Science Platform Contract ANTA1801. SR and AF were supported by the Australian Antarctic Program Partnership (AAPP) through grant funding from the Australian Government as part of the Antarctic Science Collaboration Initiative program. AKM was supported by the Australian Research Council (ARC) Australian Centre for Excellence in Antarctic Science (SR200100008) and by the ARC Discovery Project DP190100494. EA, AJSM, MM acknowledge NERC grants NE/N018095/1 (ORCHESTRA), NE/V013254/1 (ENCORE), and NE/W004933/1 (BIOPOLE). This project has received funding from the European Union?s Horizon 2020 research and innovation program under grant agreement no. 821001. This research was supported by OCEAN:ICE, which is co-funded by the European Union, Horizon Europe Funding Programme for research and innovation under grant agreement no. 101060452 and by UK Research and Innovation. O:I Contribution number 1. FH was supported by the European Union (ERC, VERTEXSO, 101041743) and the Initiative and Networking Fund of the Helmholtz Association (Grant Number: VH-NG-19-33). WL was supported by the Korea Institute of Marine Science \& Technology Promotion (KIMST) funded by the Ministry of Oceans and Fisheries (RS-2023-00256677; PM23020). Acknowledgments Publisher Copyright: Copyright {\copyright} 2023 Silvano, Purkey, Gordon, Castagno, Stewart, Rintoul, Foppert, Gunn, Herraiz-Borreguero, Aoki, Nakayama, Naveira Garabato, Spingys, Akhoudas, Sall{\'e}e, de Lavergne, Abrahamsen, Meijers, Meredith, Zhou, Tamura, Yamazaki, Ohshima, Falco, Budillon, Hattermann, Janout, Llanillo, Bowen, Darelius, {\O}sterhus, Nicholls, Stevens, Fernandez, Cimoli, Jacobs, Morrison, Hogg, Haumann, Mashayek, Wang, Kerr, Williams and Lee.}, journal = {Frontiers in Marine Science}, keywords = {Antarctic Bottom Water (AABW), Antarctic sea ice, ice shelves, observations, ocean freshening, ocean warming, Southern Ocean}, url = {https://eprints.soton.ac.uk/485726/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Dense, cold waters formed on Antarctic continental shelves descend along the Antarctic continental margin, where they mix with other Southern Ocean waters to form Antarctic Bottom Water (AABW). AABW then spreads into the deepest parts of all major ocean basins, isolating heat and carbon from the atmosphere for centuries. Despite AABW?s key role in regulating Earth?s climate on long time scales and in recording Southern Ocean conditions, AABW remains poorly observed. This lack of observational data is mostly due to two factors. First, AABW originates on the Antarctic continental shelf and slope where in situ measurements are limited and ocean observations by satellites are hampered by persistent sea ice cover and long periods of darkness in winter. Second, north of the Antarctic continental slope, AABW is found below approximately 2 km depth, where in situ observations are also scarce and satellites cannot provide direct measurements. Here, we review progress made during the past decades in observing AABW. We describe 1) long-term monitoring obtained by moorings, by ship-based surveys, and beneath ice shelves through bore holes; 2) the recent development of autonomous observing tools in coastal Antarctic and deep ocean systems; and 3) alternative approaches including data assimilation models and satellite-derived proxies. The variety of approaches is beginning to transform our understanding of AABW, including its formation processes, temporal variability, and contribution to the lower limb of the global ocean meridional overturning circulation. In particular, these observations highlight the key role played by winds, sea ice, and the Antarctic Ice Sheet in AABW-related processes. We conclude by discussing future avenues for observing and understanding AABW, impressing the need for a sustained and coordinated observing system.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton348329, volume = {349}, number = {2}, month = {October}, author = {Dan A. Smale and David K.A. Barnes and Keiron P.P. Fraser and Paul J. Mann and Matt P. Brown}, title = {Scavenging in Antarctica: intense variation between sites and seasons in shallow benthic necrophagy}, journal = {Journal of Experimental Marine Biology and Ecology}, pages = {405--417}, year = {2007}, keywords = {baited camera, consumption rates, necrophagy, scavengers, southern ocean}, url = {https://eprints.soton.ac.uk/348329/}, abstract = {The response of scavengers to a feeding cue at Adelaide Island, West Antarctic Peninsula was investigated using a baited video camera system. Fourteen experimental deployments, each lasting 72 h were conducted at two contrasting sites during the winter and summer of 2005. The rate of bait consumption varied between sites but not between seasons, and was low in comparison with studies at lower latitudes and greater depths. At the Hangar Cove site, the nemertean Parborlasia corrugatus was out-competed at the bait and displaced by the lysianassid amphipod Cheirmedon femoratus during winter. However, C. femoratus did not feed on the bait during summer, allowing P. corrugatus to monopolise the feeding opportunity. At the South Cove site the asteroid Odontaster validus dominated the bait in both seasons but sporadic feeding by the nototheniid fish Notothenia coriiceps considerably affected consumption rates during two of the six deployments. Scavengers were attracted to the bait in very high numbers and opportunistic necrophagy seems to be a successful strategy in an environment that is intensely disturbed by ice.} } @article{soton15822, volume = {109}, number = {C5}, title = {Upper ocean temperature and the baroclinic transport stream function relationship in Drake Passage}, author = {S. Sokolov and B.A. King and S.R. Rintoul and R.L. Rojas}, year = {2004}, pages = {C05001}, journal = {Journal of Geophysical Research}, keywords = {Antarctic Circumpolar Current, baroclinic transport, Southern Ocean}, url = {https://eprints.soton.ac.uk/15822/}, abstract = {Repeat hydrographic sections across the Antarctic Circumpolar Current (ACC) in Drake Passage are used to derive an empirical relationship between upper ocean temperature and the baroclinic transport stream function. Cross validation shows this relationship can be used to infer baroclinic transport (above and relative to 2500 m) from expendable bathythermograph (XBT) temperature measurements with an error of a few per cent. Transport errors of less than 2 Sv are obtained if temperature at depths between 600 and 1600 m is used to define the relationship. Temperature at depths above 300 m provides an unreliable index of transport because of variability in temperature-salinity (T-S) properties produced by air-sea interaction. The scatter in the relationship between temperature and stream function from repeat observations along a single line is similar in magnitude to the scatter observed when data from the broader Drake Passage area are considered. In both cases, variability about the mean temperature-stream function relationship reflects advection of water with anomalous T-S properties. The tight relationship between temperature and stream function in Drake Passage and south of Australia suggests baroclinic transports can be inferred from XBT temperatures with high accuracy in the Southern Ocean, providing a cost-effective means of monitoring ACC variability. However, care must be taken at the end points, particularly in the Drake Passage where the strong flow of the Subantarctic Front sometimes lies over the continental slope.} } @techreport{soton15511, type = {Project Report}, title = {RRS James Clark Ross Cruise 115, 01 Dec-19 Dec 2004. Drake Passage repeat hydrography: WOCE Southern Repeat Section 1b - Burdwood Bank to Elephant Island}, author = {M. Sparrow and E.J. Hawker}, publisher = {Southampton Oceanography Centre, University of Southampton}, year = {2005}, series = {56}, keywords = {Antarctic Circumpolar Current, Antarctic Ocean, ADCP, Acoustic Doppler Current Profiler, cruise 115 2004, CTD Observations, Drake Passage, James Clark Ross, Lowered ADCP, LADCP, Southern Ocean, Vessel-Mounted ADCP, WOCE, World Ocean Circulation Experiment}, url = {https://eprints.soton.ac.uk/15511/}, abstract = {This report describes the tenth occupation of the Drake Passage section, established during the World Ocean Circulation Experiment as repeat section SR1b. It was first occupied by Southampton Oceanography Centre in collaboration with the British Antarctic Survey in 1993, and has been re-occupied most years. Thirty-five full depth stations were completed, and 2 repeat shallow stations for biogeochemical sampling only. The full depth stations included a test station, the 30 stations for the SR1b Drake Passage section, with three repeat stations south of Burdwood Bank and one station in the ice in the Bellingshausen Sea for Dr. Mark Brandon. The CTD was a Sea-Bird 911plus with dual temperature and conductivity sensors, an altimeter, an oxygen sensor, a PAR (photosynthetically active radiation) sensor and a fluorometer. For 27 of the 30 SR1b stations LADCP data was also collected. The LADCP was a downward looking RDI Workhorse WH300 ADCP (WH) unit. Various underway measurements included navigation, VM-ADCP, sea surface temperature and salinity, water depth and meteorological parameters.} } @article{soton347640, volume = {42}, number = {12}, title = {Turbulence and Diapycnal Mixing in Drake Passage}, author = {L. St. Laurent and A.C. Naveira Garabato and J.R. Ledwell and A.M. Thurnherr and J.M. Toole and A.J. Watson}, year = {2012}, pages = {2143--2152}, journal = {Journal of Physical Oceanography}, keywords = {Southern Ocean, Turbulence, Diapycnal mixing}, url = {https://eprints.soton.ac.uk/347640/}, abstract = {Direct measurements of turbulence levels in the Drake Passage region of the Southern Ocean show a marked enhancement over the Phoenix Ridge. At this site, the Antarctic Circumpolar Current (ACC) is constricted in its flow between the southern tip of South America and the northern tip of the Antarctic Peninsula. Observed turbulent kinetic energy dissipation rates are enhanced in the regions corresponding to the ACC frontal zones where strong flow reaches the bottom. In these areas, turbulent dissipation levels reach 10?8 W kg?1 at abyssal and middepths. The mixing enhancement in the frontal regions is sufficient to elevate the diapycnal turbulent diffusivity acting in the deep water above the axis of the ridge to 1 {$\times$} 10?4 m2 s?1. This level is an order of magnitude larger than the mixing levels observed upstream in the ACC above smoother bathymetry. Outside of the frontal regions, dissipation rates are O(10?10) W kg?1, comparable to the background levels of turbulence found throughout most mid- and low-latitude regions of the global ocean.} } @techreport{soton50065, month = {January}, type = {Project Report}, title = {RRS James Clark Ross Cruise 139, 05 Dec-12 Dec 2005. Drake Passage Repeat Hydrography: WOCE Southern Repeat Section 1b ? Burdwood Bank to Elephant Island}, author = {K. Stansfield and M. Meredith}, publisher = {National Oceanography Centre}, year = {2008}, series = {24}, keywords = {ADCP, Antarctic Circumpolar Current, Antarctic Ocean, Acoustic Doppler Current Profiler, cruise 139 2005, CTD Observations, Drake Passage, James Clark Ross, Lowered ADCP, LADCP, Southern Ocean, Vessel Mounted ADCP, WOCE, World Ocean Circulation Experiment}, url = {https://eprints.soton.ac.uk/50065/}, abstract = {This report describes the eleventh occupation of the Drake Passage section, established{\ensuremath{<}}br/{\ensuremath{>}}during the World Ocean Circulation Experiment as repeat section SR1b. It was first occupied{\ensuremath{<}}br/{\ensuremath{>}}by Southampton Oceanography Centre in collaboration with the British Antarctic Survey in{\ensuremath{<}}br/{\ensuremath{>}}1993, and has been re-occupied most years. Thirty full depth stations were completed. The{\ensuremath{<}}br/{\ensuremath{>}}CTD was a Sea-Bird 911plus with dual temperature and conductivity sensors, an altimeter, an{\ensuremath{<}}br/{\ensuremath{>}}oxygen sensor, a transmissometer and a fluorometer. In addition, a SBE35 temperature{\ensuremath{<}}br/{\ensuremath{>}}sensor and a downward looking RDI Workhorse WH300 ADCP (WH) unit were attached to{\ensuremath{<}}br/{\ensuremath{>}}the CTD frame. On each station, the SBE35 collected data when the water sample bottles{\ensuremath{<}}br/{\ensuremath{>}}were fired and a LADCP profile was logged. The underway measurements included{\ensuremath{<}}br/{\ensuremath{>}}navigation, VM-ADCP, sea surface temperature and salinity, water depth and meteorological{\ensuremath{<}}br/{\ensuremath{>}}parameters.} } @article{soton368776, volume = {317-318}, month = {February}, title = {The hafnium and neodymium isotope composition of seawater in the Atlantic sector of the Southern Ocean}, author = {Torben Stichel and Martin Frank and J{\"o}rg Rickli and Brian A. Haley}, year = {2012}, pages = {282--294}, journal = {Earth and Planetary Science Letters}, keywords = {hafnium, neodymium, seawater, Southern Ocean, radiogenic isotopes}, url = {https://eprints.soton.ac.uk/368776/}, abstract = {We present the first combined dissolved hafnium (Hf) and neodymium (Nd) concentrations and isotope compositions of deep water masses from the Atlantic sector of the Southern Ocean. Eight full depth profiles were analyzed for Hf and twelve for Nd. Hafnium concentrations are generally depleted in the upper few hundred meters ranging between 0.2 pmol/kg and 0.4 pmol/kg and increase to relatively constant values of around 0.6 pmol/kg in the deeper water column. At the stations north of the Polar Front (PF), Nd concentrations increase linearly from about 10 pmol/kg at depths of {\texttt{\char126}} 200 m to up to 31 pmol/kg close to the bottom indicating particle scavenging and release. Within the Weddell Gyre (WG), however, Nd concentrations are essentially constant at 25 pmol/kg at depths greater than {\texttt{\char126}} 1000 m. The distributions of both elements show a positive correlation with dissolved silicon implying a close linkage to diatom biogeochemistry.{\ensuremath{<}}br/{\ensuremath{>}}{\ensuremath{<}}br/{\ensuremath{>}}Hafnium essentially shows invariant isotope compositions with values averaging at ?Hf = + 4.6, whereas Nd isotopes mark distinct differences between water masses, such as modified North Atlantic Deep Water (NADW, ?Nd = ? 11 to ? 10) and Antarctic Bottom Water (AABW, ?Nd = ? 8.6 to ? 9.6), but also waters locally advected via the Agulhas Current can be identified by their unradiogenic Nd isotope compositions. Mixing calculations suggest that a small fraction of Nd is removed by particle scavenging during mixing of water masses north of the PF. Nevertheless, the Nd isotope composition has apparently not been significantly affected by uptake and release of Nd from particles, as indicated by mixing calculations. A mixing envelope of an approximated North Pacific and a North Atlantic end-member shows that Nd isotope and concentration patterns in the Lower Circumpolar Deep Water (LCDW) can be fully explained by {\texttt{\char126}} 30:70 percentage contributions of these respective end-members.} } @article{soton49871, volume = {74}, number = {1}, month = {July}, author = {E. Sultan and H. Mercier and R.T. Pollard}, title = {An inverse model of the large scale circulation in the South Indian Ocean}, journal = {Progress in Oceanography}, pages = {71--94}, year = {2007}, keywords = {Southern Indian Ocean, Inverse model, Antarctic Circumpolar Current, Weddell Gyre, Meridional overturning circulation, Mean circulation}, url = {https://eprints.soton.ac.uk/49871/}, abstract = {An overview of the large-scale circulation of the South Indian Ocean (SIO) (10?S?70?S/20?E?120?E) is proposed based on historical hydrographic data (1903?1996) synthesized with a finite-difference inverse model. The in situ density, potential temperature and salinity fields of selected hydrographic stations are projected on the basis of EOFs. Then the EOF coefficients (the projected values) are interpolated on the model grid (1? in latitude, 2? in longitude) using an objective analysis whose spatial correlation functions are fitted to the data set. The resulting fields are the input of the inverse model. This procedure filters out the small-scale features. Twelve modes are needed to keep the vertical structures of the fields but the first three modes are sufficient to reproduce the large-scale horizontal features of the SIO: the Subtropical Gyre, the Weddell Gyre, the different branches of the Antarctic Circumpolar Current.{\ensuremath{<}}br/{\ensuremath{>}}The dynamics is steady state. The estimated circulation is in geostrophic balance and satisfies mass, heat and potential vorticity conservation. The wind and air-sea heat forcing are annual means from ERS1 and ECMWF, respectively.{\ensuremath{<}}br/{\ensuremath{>}}The main features of the various current systems of the SIO are quantified and reveal topographic control of the deep and bottom circulation. The cyclonic Weddell Gyre, mainly barotropic, transports 45 Sv (1 Sv = 106m3/s), and has an eastern extension limited by the southern part of the Antarctic Circumpolar Current.{\ensuremath{<}}br/{\ensuremath{>}}The bottom circulation north of 50?S is complex. The Deep Western Boundary Currents are identified as well as cyclonic recirculations. South east of the Kerguelen Plateau, the bottom circulation is in good agreement with previous water mass analysis. The comparison between some recent regional analysis and the inverse estimation is limited by the model resolution and lack of deep data.{\ensuremath{<}}br/{\ensuremath{>}}The meridional overturning circulation (MOC) is estimated from the finite difference inverse model. Between 26?S and 32?S the reversal of the current deepens and reaches 1400 m at 32?S. The major part of the deep meridional transport at 32?S is located between the African coast and the Madagascar Ridge, carried by the Agulhas Undercurrent. The mean value for this meridional thermohaline recirculation is 8.8 {$\pm$} 4.4 Sv between 26?S and 32?S. The Agulhas Undercurrent (11 Sv) is associated with a weak Agulhas Current (55 Sv). The MOC is thus trapped in the western margin of the Southwest Indian Ridge. The corresponding vertical velocity along 32?S between 30?E and 42?E is 7.2 {$\times$} 10?5 {$\pm$} 8.9 {$\times$} 10?5 cm s?1. The net meridional heat flux represents ?0.53 PW at 18?S and ?0.33 PW at 32?S (negative values for southward transports). The intensity of the meridional heat flux is linked to the intensity of the Agulhas Current and to the vertical mixing.} } @article{soton378815, volume = {45}, number = {9}, month = {September}, author = {F. S{\'e}vellec and A.C. Naveira Garabato and J.A. Brearley and K.L. Sheen}, title = {Vertical flow in the Southern Ocean estimated from individual moorings}, journal = {Journal of Physical Oceanography}, pages = {2209--2220}, year = {2015}, keywords = {Geographic location/entity, Southern Ocean, Circulation/ Dynamics, Vertical motion, Observational techniques and algorithms, Buoy observations}, url = {https://eprints.soton.ac.uk/378815/}, abstract = {In this study, we demonstrate that oceanic vertical velocities can be estimated from individual mooring measurements, even for non-stationary flow. This result is obtained under three assumptions: i. weak diffusion (P{\'e}clet number ?1), ii. weak friction (Reynolds number ?1), and iii. small inertial terms (Rossby number ?1). The theoretical framework is applied to a set of 4 moorings located in the Southern Ocean. For this site, the diagnosed vertical velocities are highly variable in time, their standard deviation being one-to-two orders of magnitude greater than their mean. We demonstrate that the time-averaged vertical velocities are largely induced by geostrophic flow, and can be estimated from the time-averaged density and horizontal velocities. This suggests that local time-mean vertical velocities are primarily forced by the time-mean ocean dynamics, rather than by e.g. transient eddies or internal waves. We also show that, in the context of these four moorings, the time-mean vertical flow is consistent with stratified Taylor column dynamics in the presence of a topographic obstacle.} } @article{soton430530, volume = {46}, number = {7}, month = {April}, author = {F. S{\'e}vellec and A.C. Naveira Garabato and C. Vic and N. Ducousso}, title = {Observing the local emergence of the Southern Ocean residual-mean circulation}, journal = {Geophysical Research Letters}, pages = {3862--3870}, year = {2019}, keywords = {Eulerian circulation, meridional overturning, mesoscale turbulence, mooring measurements, residual-mean circulation, Southern Ocean}, url = {https://eprints.soton.ac.uk/430530/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}} The role of mesoscale turbulence in maintaining the mean buoyancy structure and overturning circulation of the Southern Ocean is investigated through a 2-year-long, single-mooring record of measurements in Drake Passage. The buoyancy budget of the area is successively assessed within the Eulerian and the Temporal-Residual-Mean frameworks. We find that a regime change occurs on time scales of 1 to 100 days, characteristic of mesoscale dynamics, whereby the eddy-induced turbulent horizontal advection balances the vertical buoyancy advection by the mean flow. We use these diagnostics to reconstruct the region's overturning circulation, which is found to entail an equatorward downwelling of Antarctic Intermediate and Bottom Waters and a poleward upwelling of Circumpolar Deep Water. The estimated eddy-induced flow can be accurately parameterized via the Gent-McWilliams closure by adopting a diffusivity of {$\sim$}2,000 m {\ensuremath{<}}sup{\ensuremath{>}}2{\ensuremath{<}}/sup{\ensuremath{>}}  s {\ensuremath{<}}sup{\ensuremath{>}}?1{\ensuremath{<}}/sup{\ensuremath{>}} with a middepth increase to 2,500 m {\ensuremath{<}}sup{\ensuremath{>}}2{\ensuremath{<}}/sup{\ensuremath{>}}  s {\ensuremath{<}}sup{\ensuremath{>}}?1{\ensuremath{<}}/sup{\ensuremath{>}} at 2,100 m, immediately underneath the maximum interior stratification. {\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton339742, volume = {58}, number = {17-18}, month = {September}, author = {Florian S{\'e}vellec and Alexey V. Fedorov}, title = {Stability of the Atlantic meridional overturning circulation and stratification in a zonally averaged ocean model: Effects of freshwater flux, Southern Ocean winds, and diapycnal diffusion}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, pages = {1927--1943}, year = {2011}, keywords = {cean circulation, amoc, southern ocean, stability, hysteresis, freshwater fluxes}, url = {https://eprints.soton.ac.uk/339742/}, abstract = {The Atlantic Meridional Overturning Circulation (AMOC) is a crucial component of the global climate system. In this study, using a zonally averaged ocean model, we reexamine the sensitivity of this circulation, and ocean density structure in general, to several types of external forcing. The basin of the model extends from northern high latitudes to Antarctica and includes an implicit representation of a circumpolar channel in the South, and ocean circulation is driven by surface buoyancy fluxes and wind forcing. In contrast to earlier two-dimensional studies of the AMOC, our approach involves a careful treatment of the residual mean circulation (comprising the Eulerian-mean and eddy-induced flows), which is especially important for the Southern Ocean dynamics. Using boundary conditions consistent with present-day observations the model reproduces realistic ocean stratification and meridional overturning. The structure, intensity, and stability of the overturning are then extensively studied using three control parameters: the strength of westerly wind stress over the Southern Ocean, the magnitude of freshwater fluxes imposed on the northern Atlantic, and ocean diapycnal diffusivity. In a realistic parameter range, we estimate the AMOC sensitivity to changes in the Southern Ocean winds on the order of 1 Sv per 20\% increase in the wind stress. The overturning also increases with diapycnal diffusivity, but the dependence is weaker than in the absence of the winds. The model can undergo a shutdown of the overturning (subject to a hysteresis) when either the freshwater forcing gradually increases or the wind stress decreases. The hysteresis loop disappears for large values of isopycnal diffusivity. Changes in the AMOC intensity are accompanied by changes in the volume transport of the Antarctic Circumpolar Current. Specifically, the AMOC collapse leads to a strengthening of this transport. Ultimately, our calculations produce stability maps for the steady states of the meridional overturning circulation and provide a general framework that potentially can be used to compare different models, or to understand past abrupt climate changes related to reorganization of the AMOC.} } @article{soton476752, volume = {305}, month = {April}, title = {Mid-Holocene intensification of Southern Hemisphere westerly winds and implications for regional climate dynamics}, author = {Jamie Tamhane and Zo{\"e} A. Thomas and Haidee Cadd and Matthew R.P. Harris and Chris Turney and Christopher E. Marjo and Huixin Wang and Rabeya Akter and Panayiotis Panaretos and Amalia Halim and Patricia S. Gadd and Stefanie Carter and Paul Brickle}, year = {2023}, note = {Funding Information: We acknowledge Dr Bill Hiscock and Juee Vohra of UNSW MWAC for their work with radiocarbon dating. We would also like to acknowledge the families of Weddell Island, specifically Lewis Clifton, Stephen Clifton, Robert Short and Jo Turner, for facilitating and assisting with field work in the Falkland Islands. This work was supported by an ARC DECRA Fellowship (DE200100907) awarded to Dr Z. Thomas.}, journal = {Quaternary Science Reviews}, keywords = {Amundsen Sea Low, cryptotephra, dust, Falkland Islands, HYSPLIT, Itrax, peat, radiocarbon dating, rare earth elements, Southern Hemisphere westerly winds}, url = {https://eprints.soton.ac.uk/476752/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}The Southern Hemisphere westerly winds (SWW), a belt of strong zonal winds in the mid-latitudes, play a key role in Southern Hemisphere climate variability. Recent intensification and southwards migration of the SWW is projected to continue due to anthropogenic climate change and despite a recovering Antarctic ozone hole, impacting regional hydroclimate, ocean circulation and carbon cycling. Despite the importance of the SWW, our understanding of their behaviour on centennial to millennial timescales is limited by the inherently short observational record and limited palaeo-archive agreement on the wind belt's Holocene dynamics. Here we utilise dust flux, Itrax core scanning, rare earth element composition and HYSPLIT particle modelling to present a 8700-year (10,500?1700 cal yr BP) reconstruction of local SWW intensity from a Falkland Islands (Islas Malvinas) peat sediment core which, along with other reconstructions, we interpret in a regional South Atlantic and hemispheric context. We find increased dust deposition and variability from ca. 5700 cal yr BP, signalling an intensification and possible southwards shift of the SWW, though Patagonia likely remains the primary distal dust source throughout our record. Additionally, we identify asymmetric behaviour in the SWW belt from 3000 to 1700 cal yr BP over southern South America and the southwest Atlantic. In alignment with these findings, we propose a possible eastwards projection of the Amundsen Sea Low (ASL) into the South Atlantic during this period. Two volcanic eruptions, likely from Mt Burney (ca. 9700 cal yr BP) and Mt Hudson (ca. 4100 cal yr BP), are captured as cryptotephra deposits in the record. Our precisely dated, high-resolution multiproxy record of South Atlantic wind-blown transport provides an important new dataset that accurately constrains SWW Holocene variability over the Falkland Islands.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton336382, volume = {59-60}, month = {January}, title = {Seasonal trophic structure of the Scotia Sea pelagic ecosystem considered through biomass spectra and stable isotope analysis}, author = {G.A. Tarling and G. Stowasser and P. Ward and A.J. Poulton and M. Zhou and H.J. Venables and R.A.R. McGill and E.J. Murphy}, year = {2012}, pages = {222--236}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Southern Ocean, Phytoplankton, Zooplankton, Nekton, Myctophids, Predator?prey interactions}, url = {https://eprints.soton.ac.uk/336382/}, abstract = {The biomass size structure of pelagic communities provides a system level perspective that can be instructive when considering trophic interactions. Such perspectives can become even more powerful when combined with taxonomic information and stable isotope analysis. Here we apply these approaches to the pelagic community of the Scotia Sea (Southern Ocean) and consider the structure and development of trophic interactions over different years and seasons. Samples were collected from three open-ocean cruises during the austral spring 2006, summer 2008 and autumn 2009. Three main sampling techniques were employed: sampling bottles for microplankton (0?50 m), vertically hauled fine meshed nets for mesozooplankton (0?400 m) and coarse-meshed trawls for macrozooplankton and nekton (0?1000 m). All samples were identified to the lowest practicable taxonomic level and their abundance, individual body weight and biomass (in terms of carbon) estimated. Slopes of normalised biomass spectrum versus size showed a significant but not substantial difference between cruises and were between ?1.09 and ?1.06. These slopes were shallower than expected for a community at equilibrium and indicated that there was an accumulation of biomass in the larger size classes (101?105 mg C ind?1). A secondary structure of biomass domes was also apparent, with the domes being 2.5?3 log10 intervals apart in spring and summer and 2 log10 intervals apart in autumn. The recruitment of copepod-consuming macrozooplankton, Euphausia triacantha and Themisto gaudichaudii into an additional biomass dome was responsible for the decrease in the inter-dome interval in autumn. Predator to prey mass ratios estimated from stable isotope analysis reached a minimum in autumn while the estimated trophic level of myctophid fish was highest in that season. This reflected greater amounts of internal recycling and increased numbers of trophic levels in autumn compared to earlier times of the year. The accumulation of biomass in larger size classes throughout the year in the Scotia Sea may reflect the prevalence of species that store energy and have multiyear life-cycles.} } @article{soton351002, volume = {39}, number = {3-4}, month = {August}, author = {Pascal Terray and Kakitha Kamala and S{\'e}bastien Masson and Gurvan Madec and A.K. Sahai and Jing-Jia Luo and Toshio Yamagata}, title = {The role of the intra-daily SST variability in the Indian monsoon variability and monsoon-ENSO?IOD relationships in a global coupled model}, journal = {Climate Dynamics}, pages = {729--754}, year = {2012}, keywords = {Indian summer monsoon El Ni{\~n}o-Southern Oscillation Intra-daily SST variability Ocean?atmosphere interactions Coupled climate model}, url = {https://eprints.soton.ac.uk/351002/}, abstract = {The impact of diurnal SST coupling and vertical oceanic resolution on the simulation of the Indian Summer Monsoon (ISM) and its relationships with El Ni{\~n}o-Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) events are studied through the analysis of four integrations of a high resolution Coupled General Circulation Model (CGCM), but with different configurations. The only differences between the four integrations are the frequency of coupling between the ocean and atmosphere for the Sea Surface Temperature (SST) parameter (2 vs. 24 h coupling) and/or the vertical oceanic resolution (31 vs. 301 levels) in the CGCM. Although the summer mean tropical climate is reasonably well captured with all the configurations of the CGCM and is not significantly modified by changing the frequency of SST coupling from once to twelve per day, the ISM?ENSO teleconnections are rather poorly simulated in the two simulations in which SST is exchanged only once per day, independently of the vertical oceanic resolution used in the CGCM. Surprisingly, when 2 h SST coupling is implemented in the CGCM, the ISM?ENSO teleconnection is better simulated, particularly, the complex lead-lag relationships between the two phenomena, in which a weak ISM occurs during the developing phase of an El Ni{\~n}o event in the Pacific, are closely resembling the observed ones. Evidence is presented to show that these improvements are related to changes in the characteristics of the model?s El Ni{\~n}o which has a more realistic evolution in its developing and decaying phases, a stronger amplitude and a shift to lower frequencies when a 2-hourly SST coupling strategy is implemented without any significant changes in the basic state of the CGCM. As a consequence of these improvements in ENSO variability, the lead relationships between Indo-Pacific SSTs and ISM rainfall resemble the observed patterns more closely, the ISM?ENSO teleconnection is strengthened during boreal summer and ISM rainfall power spectrum is in better agreement with observations. On the other hand, the ISM?IOD teleconnection is sensitive to both SST coupling frequency and the vertical oceanic resolution, but increasing the vertical oceanic resolution is degrading the ISM?IOD teleconnection in the CGCM. These results highlight the need of a proper assessment of both temporal scale interactions and coupling strategies in order to improve current CGCMs. These results, which must be confirmed with other CGCMs, have also important implications for dynamical seasonal prediction systems or climate change projections of the monsoon.} } @article{soton38985, volume = {301}, number = {2}, month = {April}, author = {S. Thatje and G.A. Lovrich and G. Torres and W. Hagen and K. Anger}, title = {Changes in biomass, lipid, fatty acid and elemental composition during the abbreviated larval development of the subantarctic shrimp Campylonotus vagans}, journal = {Journal of Experimental Marine Biology and Ecology}, pages = {159--174}, year = {2004}, keywords = {Abbreviated larval development, Fatty acids, Lipids, Protein, Shrimp, Southern Ocean}, url = {https://eprints.soton.ac.uk/38985/}, abstract = {Ontogenetic changes in biomass and chemical composition were studied in the laboratory during the abbreviated larval and early juvenile development of the caridean shrimp Campylonotus vagans from the subantarctic Beagle Channel, Argentina. At 7{$\pm$}0.5 ?C, development from hatching to metamorphosis took about 44 days. The larvae started feeding on Artemia nauplii immediately after hatching, although larval resistance to starvation was high (average 18 days, maximum 29 days). Dry mass (DM), carbon (C), nitrogen (N) and hydrogen (H) contents increased about a fourfold from hatching to metamorphosis, while the C:N mass ratio increased from about 3.7 to 4.3. The protein and total lipid contents increased gradually from hatching to the first juvenile stage, the former from 190 to 640 ?g/individual, the latter from 37 to 95 ?g/individual. The lipid mass fraction was low throughout larval development (3?9\% of DM), while the protein content was much higher and almost constant (30?40\%). The dominating fatty acids were 18:1(n-9), 16:0, 20:5(n-3), 18:1(n-7), 18:3(n-3), 18:0, 16:1(n-7). Except for 20:5(n-3), these resulted mainly from food uptake (Artemia nauplii). Exuvial losses of C, H and N (all larval stages combined) accounted for only 7\%, 1\% and 1\% of the initial values at hatching. In contrast, 37\% of initial DM was lost. Partially food-independent (endotrophic) larval development is discussed as an adaptation to food scarcity at high latitudes, while the abbreviated planktotrophic larval development appears to be synchronised with seasonal peaks in primary production, allowing for an optimal resource exploitation in a food-limited environment. {\ensuremath{<}}br/{\ensuremath{>}}} } @article{soton38011, volume = {260}, month = {September}, title = {Developmental trade-offs in Subantarctic meroplankton communities and the enigma of low decapod diversity in high southern latitudes}, author = {S. Thatje and S. Schnack-Schiel and W.E. Arntz}, year = {2003}, pages = {195--207}, journal = {Marine Ecology Progress Series}, keywords = {decapoda, reproductive strategies, southern ocean, abbreviated larval development, magellan region, antarctic}, url = {https://eprints.soton.ac.uk/38011/}, abstract = {Developmental modes, occurrence and distribution patterns of invertebrate larvae were studied in the Subantarctic Magellan region of South America on the basis of quantitative plankton hauls obtained during the ?Victor Hensen? campaign in November 1994. The meroplankton community was found to be numerically dominated by decapod crustacean larvae (47\%), followed by polychaetes (20\%), echinoderms (16\%), cirripedes (8\%) and molluscs (7\%). A rich decapod community was detected, with 2 thalassinid, 5 brachyuran, 4 anomuran, 6 caridean, 1 astacid and 1 palinurid species/morphotypes identified. {\ensuremath{<}}br/{\ensuremath{>}}Cluster analyses clearly distinguished deep-water stations (250 to 400 m) south of the Straits of Magellan from shallow-water stations (30 to 100 m) in the Beagle Channel, where meroplankton was dominated by decapod larvae (\>90\%). Three main larval developmental modes, characterised by morphogenesis, mode of larval nutrition and site of larval development, were observed in Magellan decapods: (1) Extended, planktotrophic development of planktonic larvae; (2) abbreviated, planktotrophic development of planktonic larvae; and (3) abbreviated, endotrophic (lecithotrophic) development of demersally living larvae. {\ensuremath{<}}br/{\ensuremath{>}}Several caridean shrimps with abbreviated larval development, which have congeners in the Antarctic, suggest a strong synchronisation between abbreviated planktotrophic larval development and short periods of primary production. This seems to be an essential factor in early life history adaptation for the colonisation of the Antarctic environment. The impoverished Antarctic decapod fauna, with only a few representatives of caridean shrimp species left, may be related to the lack in flexibility of reptant decapods in distributing energy resources between adults and their offspring, which would allow abbreviated planktotrophic larval development.} } @article{soton444769, volume = {101}, number = {11}, month = {November}, author = {Sven Thatje and Kathryn E. Smith and James B. Mcclintock and Richard B. Aronson}, note = {Funding Information: We would like to thank John Pastor and Martin Thiel for constructively commenting on the manuscript. This research was supported by National Science Foundation grants ANT-0838846 and ANT-1141877 to RBA and ANT-0838844 and ANT-1141896 to JBM. This is contribution 320 from the Institute for Global Ecology at the Florida Institute of Technology.}, title = {From deep to shallow seas: Antarctic king crab on the move}, journal = {Ecology}, year = {2020}, keywords = {Crustacea, Lithodidae, Southern Ocean, Western Antarctic Peninsula, benthos, cold adaptation, food web, predator, reproduction, temperature}, url = {https://eprints.soton.ac.uk/444769/}, abstract = {The fauna of decapod crustaceans in the Southern Ocean has historically been considered impoverished, with only about a dozen species of decapod shrimp overall, of which only three species are common and abundant on the Antarctic continental shelf. Crabs and lobsters were assumed to be absent or very rare in the Southern Ocean, mainly ascribed to the physiological constraint of cold polar waters. Polar temperatures have been hypothesized to reduce decapod activity, especially in combination with high magnesium levels in the hemolymph ([Mg2+]HL), as [Mg2+] has a relaxant effect. Mg2+ is abundant in seawater and in combination with polar temperatures causes a relaxant effect in Crustacea (Frederich et al. 2001). Because most crabs are capable of regulating [Mg2+]HL only slightly below the [Mg2+] of seawater, their ability to maintain activity should be hampered (Frederich et al. 2001, Aronson et al. 2015a). In contrast, caridean shrimp regulate [Mg2+]HL to very low levels. The combined effect of low temperatures and high [Mg2+]HL might explain the limits of cold tolerance in decapods and has been put forward as the principal reason for the absence of crabs and lobsters from the high?polar regions (Frederich et al. 2001, Aronson et al. 2015a). These large, benthic, shell?crushing decapods, along with shell?crushing teleosts and elasmobranchs, are important in structuring benthic communities at lower latitudes.} } @article{soton476221, volume = {61}, number = {4}, month = {August}, author = {Zo{\"e} A. Thomas and Chris S.M. Turney and Alan Hogg and Alan N. Williams and Chris J. Fogwill}, note = {Funding Information: CSMT and CF acknowledge the support of the Australian Research Council (FL100100195, FT120100004 and DP130104156). We thank the captain and crew of the Fishery Patrol Vessel The Pharos for travel to and from South Georgia, and the Government of South Georgia and the South Sandwich Islands, and the Falkland Islands Government for permission to undertake sampling on the island (permit numbers SGEP0110/11 and R07/2011, respectively). Darren Christie kindly assisted with the fieldwork on the Falkland Islands, and Charlotte Cook helped prepare the samples in the laboratory. We would like to thank two anonymous reviewers and Associate Editor Pieter Grootes for their thorough reviews and helpful comments, which helped to improve the manuscript. Publisher Copyright: {\copyright} 2019 by the Arizona Board of Regents on behalf of the University of Arizona.}, title = {Investigating Subantarctic {\ensuremath{<}}sup{\ensuremath{>}}14{\ensuremath{<}}/sup{\ensuremath{>}}C Ages of different peat components: site and sample selection for developing robust age models in dynamic landscapes}, year = {2019}, journal = {Radiocarbon}, pages = {1009--1027}, keywords = {age modeling, climate change, reworking, Southern Ocean, terrestrial}, url = {https://eprints.soton.ac.uk/476221/}, abstract = {Precise radiocarbon (14C) dating of sedimentary sequences is important for developing robust chronologies of environmental change, but sampling of suitable components can be challenging in highly dynamic landscapes. Here we investigate radiocarbon determinations of different peat size fractions from six peat sites, representing a range of geomorphological contexts on the South Atlantic subantarctic islands of the Falklands and South Georgia. To investigate the most suitable fraction for dating, 112 measurements were obtained from three components within selected horizons: a fine fraction \<0.2 mm, a coarse fraction \>0.2 mm, and bulk material. We find site selection is critical, with locations surrounded by high-ground and/or relatively slowly accumulating sites more susceptible to the translocation of older carbon. Importantly, in locations with reduced potential for redeposition of material, our results show that there is no significant or systematic difference between ages derived from bulk material, fine or coarse (plant macrofossil) material, providing confidence in the resulting age model. Crucially, in areas comprising complex terrain with extreme relief, we recommend dating macrofossils or bulk carbon rather than a fine fraction, or employing comprehensive dating of multiple sedimentary fractions to determine the most reliable fraction(s) for developing a robust chronological framework.} } @article{soton367960, volume = {44}, number = {7}, month = {July}, author = {Andrew F. Thompson and Alberto C. Naveira Garabato}, title = {Equilibration of the Antarctic Circumpolar Current by standing meanders}, journal = {Journal of Physical Oceanography}, pages = {1811--1828}, year = {2014}, keywords = {Geographic location/entity, Southern Ocean, Circulation/ Dynamics, Fluxes, Mesoscale processes, Stationary waves, Topographic effects, Physical Meteorology and Climatology, Vorticity}, url = {https://eprints.soton.ac.uk/367960/}, abstract = {The insensitivity of the Antarctic Circumpolar Current (ACC)?s prominent isopycnal slope to changes in wind stress is thought to stem from the action of mesoscale eddies that counterbalance the wind-driven Ekman overturning{--}a framework verified in zonally symmetric circumpolar flows. Substantial zonal variations in eddy characteristics suggest that local dynamics may modify this balance along the path of the ACC. Analysis of an eddy-resolving ocean GCM shows that the ACC can be broken into broad regions of weak eddy activity, where surface winds steepen isopycnals, and a small number of standing meanders, across which the isopycnals relax. Meanders are coincident with sites of (i) strong eddy-induced modification of the mean flow and its vertical structure as measured by the divergence of the Eliassen?Palm flux and (ii) enhancement of deep eddy kinetic energy by up to two orders of magnitude over surrounding regions. Within meanders, the vorticity budget shows a balance between the advection of relative vorticity and horizontal divergence, providing a mechanism for the generation of strong vertical velocities and rapid changes in stratification. Temporal fluctuations in these diagnostics are correlated with variability in both the Eliassen?Palm flux and bottom speed, implying a link to dissipative processes at the ocean floor. At larger scales, bottom pressure torque is spatially correlated with the barotropic advection of planetary vorticity, which links to variations in meander structure. From these results, it is proposed that the ?flexing? of standing meanders provides an alternative mechanism for reducing the sensitivity of the ACC?s baroclinicity to changes in forcing, separate from an ACC-wide change in transient eddy characteristics.} } @article{soton24569, volume = {329}, number = {2}, title = {Sewage effects on the food sources and diet of benthic foraminifera living in oxic sediment: a microcosm experiment}, author = {J.N. Topping and J.W. Murray and D.W. Pond}, year = {2006}, pages = {239--250}, journal = {Journal of Experimental Marine Biology and Ecology}, keywords = {feeding ecology, foraminifera, lipids, microcosm experiment, sewage, southern UK}, url = {https://eprints.soton.ac.uk/24569/}, abstract = {A microcosm experiment was conducted to investigate the effects of sewage-derived particulate organic matter (POM) on the food sources and diets of two species of intertidal benthic foraminifera, Ammonia beccarii and Haynesina germanica, using lipid biomarkers to determine trophic relationships. The lipid content of the sediment and associated micro-organisms was a guide to potential food sources while that of the foraminifera was a guide to what they had actually eaten. Six microcosm tanks were established, with constant salinity, temperature and oxygen content, and each with a thin layer of sediment containing living foraminifera. Three microcosms were used as controls and three were treatments to which the POM from secondary treated sewage was added. Each microcosm was treated as a single replicate (to avoid pseudoreplication). The experiment was run for 38 days. The results showed that the food sources (from the sediment) and the diet of the foraminifera did not significantly differ in the controls or the treatments, but quantities of fatty acids decreased in both the sediment system and the foraminifera over the duration of the experiment. It is concluded that sewage-POM (secondary treatment) does not have a direct effect on the food sources of the foraminifera or their diet. The foraminifera did not feed directly on the sewage-derived POM, nor did the addition of sewage stimulate growth of micro-organisms associated with the sediment system. However, recent field data collected by the authors provides evidence that season plays an important role in foraminiferal response to organic pollution (OP), and microcosm sediment might have been unknowingly collected at a time when foraminifera are now known not to respond to OP, i.e. in summer.} } @article{soton455441, volume = {41}, number = {11}, month = {November}, author = {Toby Travers and John van den Hoff and Mary Anne Lea and Kris Carlyon and Ryan Reisinger and P. J.Nico de Bruyn and Margie Morrice}, title = {Aspects of the ecology of killer whale ({\ensuremath{<}}i{\ensuremath{>}}Orcinus orca Linn.{\ensuremath{<}}/i{\ensuremath{>}}) groups in the near-shore waters of Sub-Antarctic Macquarie Island}, journal = {Polar Biology}, pages = {2249--2259}, year = {2018}, keywords = {Diet, Feeding behaviour, Group size, Southern elephant seal}, url = {https://eprints.soton.ac.uk/455441/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Occurrences of killer whales ({\ensuremath{<}}i{\ensuremath{>}}Orcinus orca{\ensuremath{<}}/i{\ensuremath{>}}) in the waters surrounding Sub-Antarctic Macquarie Island have been recorded since the 1820s; however, their presence only became the focus of scientific research in the mid-1990s. The analyses of sightings data collected from the island between 1986 and 2015 are presented herein. The study provides evidence of a relationship between killer whale sighting probability and seasonal prey availability. Killer whales were present at the island year-round with a distinct seasonal peak in November?December, and coincident with a peak in occurrence of southern elephant seals ({\ensuremath{<}}i{\ensuremath{>}}Mirounga leonina{\ensuremath{<}}/i{\ensuremath{>}}) due to breeding season activity, particularly the dispersal of weaned pups. Supporting this association and killer whales? top-down influence on the survival of juvenile and adult southern elephant seals, pinnipeds accounted for 79\% of prey identified, with weaned southern elephant seal pups contributing over a quarter of feeding events observed in the near-shore environment. Fur seals and penguins were also identified as prey. Killer whale groups had a median group size of three individuals, and groups of three to five individuals were most often observed feeding/milling in near-shore waters. The largest range in group sizes were observed during their peak occurrence in early summer, particularly in the number of sub-adult and female whales per group. Adult males made up 75\% of single occurrences, and singletons were most often observed travelling. Overall, the ecology of killer whales at Macquarie Island was similar to that of killer whales studied at other Sub-Antarctic locations, with comparable seasonality, behaviour, diet, and group structure. Much remains to be learnt regarding the seasonal movements of whales and their diet at other times of year, their relationship to killer whales sighted in coastal Australian, New Zealand and Antarctic ecosystems, and impact on diet from commercial fisheries operations and fluctuating prey populations.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton476049, volume = {159}, number = {3}, month = {March}, author = {C. S.M. Turney and J. M. Wilmshurst and R. T. Jones and J. R. Wood and J. G. Palmer and A. G. Hogg and P. Fenwick and S. F. Crowley and K. Privat and Z. Thomas}, note = {Publisher Copyright: {\copyright} 2016 Elsevier Ltd}, title = {Reconstructing atmospheric circulation over southern New Zealand: Establishment of modern westerly airflow 5500 years ago and implications for Southern Hemisphere Holocene climate change}, year = {2017}, journal = {Quaternary Science Reviews}, pages = {77--87}, keywords = {Jet stream, Roaring Forties, Southern Annular Mode (SAM), Southern Hemisphere westerly winds, Southern Ocean, Wind-blown sediments}, url = {https://eprints.soton.ac.uk/476049/}, abstract = {Late-twentieth century changes in the intensity and migration of Southern Hemisphere westerly winds have been implicated in spatially complex variability in atmospheric and ocean circulation, and ice-sheet dynamics, across the mid- to high-latitudes. A major uncertainty, however, is whether present day hemispheric-wide symmetrical airflow is representative of past behaviour. Here we report a multi-proxy study from Stewart Island and southern Fiordland, New Zealand (46?47?S) reconstructing Holocene changes at the northern limit of westerly airflow. Increased minerogenic input and a pronounced shift in cool-loving vegetation around 5500 years ago is consistent with the establishment of westerly airflow at this latitude in the southwest Pacific. In marked contrast, stronger winds are reported further south over the subantarctic Auckland (50?S) and Campbell (52?S) Islands from 8000 years ago. Intriguingly, reconstructions from the east Pacific suggest a weakening of core westerly airflow after 8500 years ago, but an expansion along the northern limits sometime after 5500 years ago. Our results suggest similar atmospheric circulation changes have been experienced in the Pacific since 5500 years ago, but indicate an expanded network of sites is needed to comprehensively test the driver(s) and impact(s) of Holocene mid-latitude westerly winds across the Southern Hemisphere.} } @article{soton476046, volume = {11}, number = {6}, month = {June}, author = {Chris S.M. Turney and Richard T. Jones and David Lister and Phil Jones and Alan N. Williams and Alan Hogg and Zo{\"e} A. Thomas and Gilbert P. Compo and Xungang Yin and Christopher J. Fogwill and Jonathan Palmer and Steve Colwell and Rob Allan and Martin Visbeck}, note = {Publisher Copyright: {\copyright} 2016 IOP Publishing Ltd.}, title = {Anomalous mid-twentieth century atmospheric circulation change over the South Atlantic compared to the last 6000 years}, journal = {Environmental Research Letters}, year = {2016}, keywords = {anthropogenic climate change, climate reanalysis, El Ni{\~n}o-Southern Oscillation (ENSO), southern annular mode (SAM), Southern Hemisphere westerlies, subantarctic climate extremes, temperature}, url = {https://eprints.soton.ac.uk/476046/}, abstract = {Determining the timing and impact of anthropogenic climate change in data-sparse regions is a considerable challenge. Arguably, nowhere is this more difficult than the Antarctic Peninsula and the subantarctic South Atlantic where observational records are relatively short but where high rates of warming have been experienced since records began. Here we interrogate recently developed monthly-resolved observational datasets from the Falkland Islands and South Georgia, and extend the records back using climate-sensitive peat growth over the past 6000 years. Investigating the subantarctic climate data with ERA-Interim and Twentieth Century Reanalysis, we find that a stepped increase in precipitation across the 1940s is related to a change in synoptic atmospheric circulation: a westward migration of quasi-permanent positive pressure anomalies in the South Atlantic has brought the subantarctic islands under the increased influence of meridional airflow associated with the Amundsen Sea Low. Analysis of three comprehensively multi-dated (using 14C and 137Cs) peat sequences across the two islands demonstrates unprecedented growth rates since the mid-twentieth century relative to the last 6000 years. Comparison to observational and reconstructed sea surface temperatures suggests this change is linked to a warming tropical Pacific Ocean. Our results imply 'modern' South Atlantic atmospheric circulation has not been under this configuration for millennia.} } @article{soton479325, volume = {31}, number = {1}, month = {January}, author = {Chris S.M. Turney and Matt McGlone and Jonathan Palmer and Christopher Fogwill and Alan Hogg and Zo{\"e} A. Thomas and Mathew Lipson and Janet M. Wilmshurst and Pavla Fenwick and Richard T. Jones and Ben Hines and Graeme F. Clark}, note = {Publisher Copyright: {\copyright} 2016 John Wiley \& Sons, Ltd.}, title = {Intensification of Southern Hemisphere westerly winds 2000-1000 years ago: Evidence from the subantarctic Campbell and Auckland Islands (52-50?S)}, year = {2016}, journal = {Journal of Quaternary Science}, pages = {12--19}, keywords = {Southern Hemisphere westerlies, Southern Ocean, Subantarctic islands, Subfossil trees, Tree line}, url = {https://eprints.soton.ac.uk/479325/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}The Southern Ocean plays a significant role in driving global climate-ocean-carbon dynamics. Unfortunately, a relative dearth of datasets across the region limits our ability to understand past and future mechanisms of change. Here we report a new dataset from the south-west Pacific: radiocarbon-dated subfossil tree stumps (Dracophyllum) eroding out from peat exposures on Campbell and Auckland Islands (52-50?S). Dracophyllum are the southernmost growing trees in the south-west Pacific and their growth on exposed sites and at altitude is strongly controlled by the prevailing westerly airflow, providing a unique measure of past changes in zonal wind strength. Here we demonstrate a significant collapse in the altitudinal limit of growth between approximately 2000 and 1000 years ago (hereafter 2-1ka), consistent with other records across the Southern Hemisphere that indicate westerly airflow was significantly enhanced. Importantly, this period in the late Holocene was one of marked change across the broader region, suggesting westerly airflow played a key role in driving Southern Ocean variability at this time.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton476055, volume = {30}, number = {2}, month = {February}, author = {Chris S.M. Turney and Jonathan Palmer and Alan Hogg and Christopher J. Fogwill and Richard T. Jones and Christopher Bronk Ramsey and Pavla Fenwick and Pauline Grierson and Janet Wilmshurst and Alison O'Donnell and Zo{\"e} A. Thomas and Mathew Lipson}, note = {Funding Information: C.S.M.T., C.F., and P.G. acknowledge the support of the Australian Research Council (FL100100195, FT120100004, and DP130104156). Publisher Copyright: {\copyright}2016. American Geophysical Union. All Rights Reserved.}, title = {Multidecadal variations in Southern Hemisphere atmospheric {\ensuremath{<}}sup{\ensuremath{>}}14{\ensuremath{<}}/sup{\ensuremath{>}}C: Evidence against a Southern Ocean sink at the end of the Little Ice Age CO{\ensuremath{<}}sub{\ensuremath{>}}2{\ensuremath{<}}/sub{\ensuremath{>}} anomaly}, year = {2016}, journal = {Global Biogeochemical Cycles}, pages = {211--218}, keywords = {interhemispheric gradient (IHG), Little Ice Age (LIA), radiocarbon (C), Southern Hemisphere carbon dioxide (CO), Southern Ocean, tree rings}, url = {https://eprints.soton.ac.uk/476055/}, abstract = {Northern Hemisphere-wide cooling during the Little Ice Age (LIA; 1650-1775 Common Era, C.E.) was associated with a {\texttt{\char126}}5 ppmv decrease in atmospheric carbon dioxide. Changes in terrestrial and ocean carbon reservoirs have been postulated as possible drivers of this relatively large shift in atmospheric CO2, potentially providing insights into the mechanisms and sensitivity of the global carbon cycle. Here we report decadally resolved radiocarbon (14C) levels in a network of tree-ring series spanning 1700-1950 C.E. located along the northern boundary of, and within, the Southern Ocean. We observe regional dilutions in atmospheric radiocarbon (relative to the Northern Hemisphere) associated with upwelling of 14CO2-depleted abyssal waters. We find the interhemispheric 14C offset approaches zero during increasing global atmospheric CO2 at the end of the LIA, with reduced ventilation in the Southern Ocean and a Northern Hemisphere source of old carbon (most probably originating from deep Arctic peat layers). The coincidence of the atmospheric CO2 increase and reduction in the interhemispheric 14C offset imply a common climate control. Possible mechanisms of synchronous change in the high latitudes of both hemispheres are discussed.} } @techreport{soton19296, editor = {A. Villwock and J. Gould}, month = {December}, type = {Project Report}, title = {CLIVAR Exchanges No. 22. Special issue on: Southern Ocean Climate Variability}, publisher = {International CLIVAR Project Office}, year = {2001}, series = {No. 22 (Vol. 6(4)}, keywords = {CLIVAR, WCRP, Exchanges, Newsletter, Southern Ocean Climate Variability}, url = {https://eprints.soton.ac.uk/19296/} } @article{soton174075, volume = {36}, number = {9-10}, title = {Interannual variability of the South Pacific Convergence Zone and implications for tropical cyclone genesis}, author = {Emmanuel M. Vincent and Matthieu Lengaigne and Christophe E. Menkes and Nicolas C. Jourdain and Patrick Marchesiello and Gurvan Madec}, year = {2011}, pages = {1881--1896}, journal = {Climate Dynamics}, keywords = {South Pacific Convergence Zone, Interannual variability, Tropical cyclone, El Ni{\~n}o Southern Oscillation}, url = {https://eprints.soton.ac.uk/174075/}, abstract = {The interannual variability of the South Pacific Convergence Zone (SPCZ) and its influence on tropical cyclone (TC) genesis in the South Pacific are investigated using observations and ERA40 reanalysis over the 1979?2002 period. In austral summer, the SPCZ displays four typical structures at interannual timescales. The first three are characterized by a diagonal orientation of the SPCZ and account for 85\% of the summer seasons. One is close to climatology and the other two exhibit a 3? northward or southward departure from the SPCZ climatological position. In contrast, the fourth one, that only encompasses three austral summer seasons (the extreme 1982/1983 and 1997/1998 El Ni{\~n}o events and the moderate 1991/1992 El Ni{\~n}o event), displays very peculiar behaviour where the SPCZ largely departs from its climatological position and is zonally oriented. Variability of the western/central Pacific equatorial sea surface temperature (SST) is shown to modulate moisture transport south of the equator, thereby strongly constraining the location of the SPCZ. The SPCZ location is also shown to strongly modulate the atmospheric circulation variability in the South Pacific with specific patterns for each class. However, independently of its wide year-to-year excursions, the SPCZ is always collocated with the zero relative vorticity at low levels while the maximum vorticity axis lies 6? to the south of the SPCZ position. This coherent atmospheric organisation in the SPCZ region is shown to constrain tropical cyclogenesis to occur preferentially within 10? south of the SPCZ location as this region combines all the large-scale atmospheric conditions that favour the breeding of TCs. This analysis also reveals that cyclogenesis in the central Pacific (in the vicinity of French Polynesia) only occurs when the SPCZ displays a zonal orientation while this observation was previously attributed to El Ni{\~n}o years in general. Different characteristics of El Ni{\~n}o Southern Oscillation (ENSO)-related Pacific equatorial warming are shown to impact differently on the SPCZ position, suggesting that for regional scales, such as the South Pacific, the SPCZ classification is more appropriate than a simple ENSO index to characterize TC interannual variability. These findings suggest that forecasting the strength of El Ni{\~n}o through SST variations in the eastern Pacific may not be sufficient to accurately predict cyclogenesis in the South Pacific, especially east of the dateline.} } @article{soton340156, volume = {103}, number = {7}, month = {October}, author = {David V{\"o}lker and Jacob Geersen and Eduardo Contreras-Reyes and Javier Sellanes and Silvio Pantoja and Wolfgang Rabbel and Martin Thorwart and Christian Reichert and Martin Block and Wilhelm Reimer Weinrebe}, title = {Morphology and geology of the continental shelf and upper slope of southern Central Chile (33?S?43?S)}, journal = {International Journal of Earth Sciences}, pages = {1765--1787}, year = {2014}, keywords = {Southern Central Chile, Bathymetry, Shelf sedimentation, Shelf basins, Submarine faults, Seismicity, Fluid seepage}, url = {https://eprints.soton.ac.uk/340156/}, abstract = {The continental shelf and slope of southern Central Chile have been subject to a number of international as well as Chilean research campaigns over the last 30 years. This work summarizes the geologic setting of the southern Central Chilean Continental shelf (33?S?43?S) using recently published geophysical, seismological, sedimentological and bio-geochemical data. Additionally, unpublished data such as reflection seismic profiles, swath bathymetry and observations on biota that allow further insights into the evolution of this continental platform are integrated. The outcome is an overview of the current knowledge about the geology of the southern Central Chilean shelf and upper slope. We observe both patches of reduced as well as high recent sedimentation on the shelf and upper slope, due to local redistribution of fluvial input, mainly governed by bottom currents and submarine canyons and highly productive upwelling zones. Shelf basins show highly variable thickness of Oligocene-Quaternary sedimentary units that are dissected by the marine continuations of upper plate faults known from land. Seismic velocity studies indicate that a paleo-accretionary complex that is sandwiched between the present, relatively small active accretionary prism and the continental crust forms the bulk of the continental margin of southern Central Chile.} } @article{soton363144, volume = {103}, number = {7}, month = {October}, author = {David V{\"o}lker and Heidi Wehrmann and Steffen Kutterolf and Karthik Iyer and Wolfgang Rabbel and Jacob Geersen and Kaj Hoernle}, title = {Constraining input and output fluxes of the southern-central Chile subduction zone: water, chlorine and sulfur}, journal = {International Journal of Earth Sciences}, pages = {2129--2153}, year = {2014}, keywords = {Subduction input, Forearc dewatering, Arc magmatism, Volcanic volatile output rates, Subduction fluids, Southern volcanic zone of Chile}, url = {https://eprints.soton.ac.uk/363144/}, abstract = {In this paper, we constrain the input and output fluxes of H2O, Cl and S into the southern-central Chilean subduction zone (31?S?46?S). We determine the input flux by calculating the amounts of water, chlorine and sulfur that are carried into the subduction zone in subducted sediments, igneous crust and hydrated lithospheric mantle. The applied models take into account that latitudinal variations in the subducting Nazca plate impact the crustal porosity and the degree of upper mantle serpentinization and thus water storage in the crust and mantle. In another step, we constrain the output fluxes of the subduction zone both to the subcontinental lithospheric mantle and to the atmosphere?geosphere?ocean by the combined use of gas flux determinations at the volcanic arc, volume calculations of volcanic rocks and the combination of mineralogical and geothermal models of the subduction zone. The calculations indicate that about 68 Tg/m/Ma of water enters the subduction zone, as averaged over its total length of 1,480 km. The volcanic output on the other hand accounts for 2 Tg/m/Ma or 3 \% of that input. We presume that a large fraction of the volatiles that are captured within the subducting sediments (which accounts for roughly one-third of the input) are cycled back into the ocean through the forearc. This assumption is however questioned by the present lack of evidence for major venting systems of the submarine forearc. The largest part of the water that is carried into the subduction zone in the crust and hydrated mantle (accounting for two-thirds of the input) appears to be transported beyond the volcanic arc.} } @inproceedings{soton455079, month = {January}, title = {Submerged Palaeolandscapes of the Southern Hemisphere (SPLOSH) - What is emerging from the Southern Hemisphere}, author = {Ingrid Ward and Alex Bastos and Diego Carabias and Hayley Cawthra and Helen Farr and Andrew Green and Fraser Sturt}, year = {2022}, keywords = {Submerged Palaeolandscape, Southern Hemisphere}, url = {https://eprints.soton.ac.uk/455079/}, abstract = {The potential of submerged palaeolandscapes to address questions about global migrations, broad-scale climate and landscape change, and human response to this has to date been concentrated in the Northern Hemisphere (NH). The Southern Hemisphere (SH) has less land, more water and water barriers, higher floral and faunal endemicity, lower population but with Indigenous populations that have maintained a connection with coastal and offshore landscapes for at least 40,000 years in Australasia, and almost 170,000 years in South Africa. We provide an overview of current knowledge in South America, Southern Africa and Australasia and explore how new palaeogeographic and palaeoecological research, alongside related coastal archaeology, is helping to map out future directions for submerged cultural landscape research in these regions. A common theme across is the need to raise awareness of submerged cultural resources and Indigenous knowledge of these as well as the multi-disciplinary approach needed to understand the unique landscapes in which they are preserved.} } @article{soton190541, volume = {277}, number = {3-4}, month = {January}, author = {Sebastian F.L. Watt and David M. Pyle and Tamsin A. Mather}, title = {The influence of Great Earthquakes on volcanic eruption rate along the Chilean subduction zone}, journal = {Earth and Planetary Science Letters}, pages = {399--407}, year = {2009}, keywords = {seismic triggering, volcanic eruption, Chile, Andean southern volcanic zone, great earthquake, eruption rates}, url = {https://eprints.soton.ac.uk/190541/}, abstract = {Seismic activity has been postulated as a trigger of volcanic eruption on a range of timescales, but demonstrating the occurrence of triggered eruptions on timescales beyond a few days has proven difficult using global datasets. Here, we use the historic earthquake and eruption records of Chile and the Andean southern volcanic zone to investigate eruption rates following large earthquakes. We show a significant increase in eruption rate following earthquakes of MW \> 8, notably in 1906 and 1960, with similar occurrences further back in the record. Eruption rates are enhanced above background levels for {\texttt{\char126}} 12 months following the 1906 and 1960 earthquakes, with the onset of 3?4 eruptions estimated to have been seismically influenced in each instance. Eruption locations suggest that these effects occur from the near-field to distances of {\texttt{\char126}} 500 km or more beyond the limits of the earthquake rupture zone. This suggests that both dynamic and static stresses associated with large earthquakes are important in eruption-triggering processes and have the potential to initiate volcanic eruption in arc settings over timescales of several months.} } @article{soton419070, volume = {19}, number = {1}, month = {January}, author = {T. Westerhold and U. R{\"o}hl and B. Donner and T. Frederichs and W.E.C. Kordesch and S.M. Bohaty and D.A. Hodell and J. Laskar and R.E. Zeebe}, title = {Late Lutetian thermal maximum{--}crossing a thermal threshold in Earth's climate system?}, journal = {Geochemistry, Geophysics, Geosystems}, pages = {73--82}, year = {2018}, keywords = {2?C warming of the deep ocean in the southern South Atlantic, Eocene transient (30 kyr) warming event at 41.52 Ma, Late Lutetian Thermal Maximum (LLTM) occurs within magnetochron C19r, LLTM coincidences with exceptionally high insolation, potential thermal threshold of Earth's climate system}, url = {https://eprints.soton.ac.uk/419070/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Recognizing and deciphering transient global warming events triggered by massive release of carbon into Earth's ocean-atmosphere climate system in the past are important for understanding climate under elevated pCO{\ensuremath{<}}sub{\ensuremath{>}}2{\ensuremath{<}}/sub{\ensuremath{>}} conditions. Here we present new high-resolution geochemical records including benthic foraminiferal stable isotope data with clear evidence of a short-lived (30 kyr) warming event at 41.52 Ma. The event occurs in the late Lutetian within magnetochron C19r and is characterized by a {$\sim$}2?C warming of the deep ocean in the southern South Atlantic. The magnitudes of the carbon and oxygen isotope excursions of the Late Lutetian Thermal Maximum are comparable to the H2 event (53.6 Ma) suggesting a similar response of the climate system to carbon cycle perturbations even in an already relatively cooler climate several million years after the Early Eocene Climate Optimum. Coincidence of the event with exceptionally high insolation values in the Northern Hemisphere at 41.52 Ma might indicate that Earth's climate system has a thermal threshold. When this tipping point is crossed, rapid positive feedback mechanisms potentially trigger transient global warming. The orbital configuration in this case could have caused prolonged warm and dry season leading to a massive release of terrestrial carbon into the ocean-atmosphere system initiating environmental change.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton481648, volume = {196}, month = {June}, title = {{\ensuremath{<}}i{\ensuremath{>}}Eurythenes sigmiferus{\ensuremath{<}}/i{\ensuremath{>}} and {\ensuremath{<}}i{\ensuremath{>}}Eurythenes andhakarae{\ensuremath{<}}/i{\ensuremath{>}} (Crustacea Amphipoda) are sympatric at the abyssal Agulhas Fracture Zone, South Atlantic Ocean, and notes on their distributions}, author = {Johanna N.J. Weston and Eva C.D. Stewart and Paige J. Maroni and Heather A. Stewart and Alan J. Jamieson}, year = {2023}, note = {Funding Information: Sea time and logistics for the Five Deeps Expedition were supported and funded by Victor Vescovo of Caladan Oceanic LLC (United States). DNA barcoding was funded by the ?Hadal Zones of Our Overseas Territories? by the Darwin Initiative funded by the UK Government ( DPLUS093 ) awarded to HAS . AJJ and PJM are supported by the Minderoo-UWA Deep-Sea Research Centre funded by the Minderoo Foundation , Australia, and JNJW through the Townsend Postdoctoral Scholarship Fund through the Woods Hole Oceanographic Institution , USA.}, journal = {Deep-Sea Research Part I: Oceanographic Research Papers}, keywords = {Amphipoda, Antarctic polar front, Cryptic species, Deep sea, DNA barcoding, Historical collections, New records, Southern ocean}, url = {https://eprints.soton.ac.uk/481648/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Cryptic species in the deep ocean are rapidly being identified with molecular evidence and as a result, new species are being described. Consequently, our understanding of distributions among the revised landscape of species needs to be reassessed. A model example is the large scavenging amphipod, Eurythenes gryllus (Lichtenstein in Mandt, 1882), which historically was thought to have a eurybathic and cosmopolitan distribution. Molecular evidence has since led to the separation of E. gryllus into ten named species and truncating its range to bi-polar bathyal depths. This study focuses on two species; Eurythenes sigmiferus and Eurythenes andhakarae d'Udekem d'Acoz and Havermans, 2015, and presents new records of both species from 5,493 m in the previously unsampled Agulhas Fracture Zone, South Atlantic Ocean (42.77?S, 10.05?E). We paired morphology with DNA barcoding at two mitochondrial regions to achieve robust identification and assessed their wider geographic range by reassessing historical records. Their overlapping presence at the Agulhas Fracture Zone expands their known ranges to the non-polar South Atlantic Ocean. Specifically, for E. sigmiferus, the data suggests this species has a multi-ocean tropical to temperate distribution from abyssal to shallow hadal depths (3,410?6,097 m). Eurythenes andhakarae is not restricted to the Southern Ocean but is distributed across the Antarctic Polar Front to the temperate South Atlantic Ocean between abyssal and hadal depths (3,069?7,099 m), with a presence at bathyal depths requiring molecular confirmation. This study highlights that pairing new expeditions with a re-inspection of rich historical collections exploration can fill in data gaps across species ranges and, ultimately, biogeography.{\ensuremath{<}}/p{\ensuremath{>}}} } @techreport{soton50085, month = {January}, author = {A.P. Williams and R.E. Hadfield}, series = {25}, editor = {G.D. Quartly}, title = {RRS James Clark Ross Cruise 163, 07 Dec-15 Dec 2006. Drake Passage Repeat Hydrography: WOCE Southern Repeat Section 1b - Burdwood Bank to Elephant Island}, type = {Project Report}, publisher = {National Oceanography Centre}, year = {2008}, keywords = {ADCP, Antarctic Ocean, Acoustic Doppler Current Profiler, cruise 163 2006, CTD Observations, Drake Passage, James Clark Ross, Lowered ADCP, LADCP, oxygen isotopes, particulate carbon, phytoplankton, Southern Ocean, WOCE, World Ocean Circulation Experiment}, url = {https://eprints.soton.ac.uk/50085/}, abstract = {This report describes the twelfth repeat hydrography section across Drake Passage, first{\ensuremath{<}}br/{\ensuremath{>}}established during the World Ocean Circulation Experiment. For this work NOC made use{\ensuremath{<}}br/{\ensuremath{>}}of the regular BAS supply trip to Rothera from the Falklands using the RRS James Clark{\ensuremath{<}}br/{\ensuremath{>}}Ross. Thirty CTD/LADCP stations were carried out across the 753 km section from{\ensuremath{<}}br/{\ensuremath{>}}Burdwood Bank to Elephant Island, plus one test station in the deep waters to the north of{\ensuremath{<}}br/{\ensuremath{>}}Burdwood Bank. Maximum station spacing on the section was 33 km, with stations closer{\ensuremath{<}}br/{\ensuremath{>}}together on the continental shelves. Water samples were drawn for salinity analysis, for{\ensuremath{<}}br/{\ensuremath{>}}subsequent CTD conductivity calibration. Samples were also drawn for analysis of oxygen{\ensuremath{<}}br/{\ensuremath{>}}isotope fraction ?18O, for later analysis back at NOC. The CTD was a SeaBird 911plus with{\ensuremath{<}}br/{\ensuremath{>}}dual temperature and conductivity sensors. There were two LADCP instruments, but no{\ensuremath{<}}br/{\ensuremath{>}}useful data were collected with them. Various underway measurements were also collected,{\ensuremath{<}}br/{\ensuremath{>}}including navigation, vessel-mounted ADCP, sea surface temperature and salinity, water{\ensuremath{<}}br/{\ensuremath{>}}depth and meteorological parameters. Water samples were also collected for subsequent{\ensuremath{<}}br/{\ensuremath{>}}analysis for chlorophyll, particulate carbon and biogenic silica.} } @article{soton372680, volume = {120}, number = {1}, month = {January}, author = {Chris Wilson and Christopher W. Hughes and Jeffrey R. Blundell}, title = {Forced and intrinsic variability in the response to increased wind stress of an idealized Southern Ocean}, journal = {Journal of Geophysical Research: Oceans}, pages = {113--130}, year = {2015}, keywords = {Southern Ocean, intrinsic variability, nonlinear dynamics, wind stress, eddy saturation, decadal}, url = {https://eprints.soton.ac.uk/372680/}, abstract = {We use ensemble runs of a three-layer, quasigeostrophic idealized Southern Ocean model to explore the roles of forced and intrinsic variability in response to a linear increase of wind stress imposed over a 30-year period. We find no increase of eastward circumpolar volume transport in response to the increased wind stress. A large part of the resulting time series can be explained by a response in which the eddy kinetic energy is linearly proportional to the wind stress with a possible time lag, but no statistically significant lag is found. However, this simple relationship is not the whole story: several intrinsic timescales also influence the response. We find an e-folding timescale for growth of small perturbations of 1-2 weeks. The energy budget for intrinsic variability at periods shorter than a year is dominated by exchange between kinetic and potential energy. At longer timescales, we find an intrinsic mode with period in the region of 15 years, which is dominated by changes in potential energy and frictional dissipation in a manner consistent with that seen by Hogg and Blundell [2006]. A similar mode influences the response to changing wind stress. This influence, robust to perturbations, is different from the supposed linear relationship between wind stress and eddy kinetic energy, and persists for 5-10 years in this model, suggestive of a forced oscillatory mode with period of around 15 years. If present in the real ocean, such a mode would imply a degree of predictability of Southern Ocean dynamics on multi-year timescales.} } @article{soton337101, volume = {326-328}, month = {April}, title = {Enhanced siliceous plankton productivity in response to middle Eocene warming at Southern Ocean ODP Sites 748 and 749}, author = {Jakub Witkowski and Steven M. Bohaty and Kevin McCartney and David M. Harwood}, year = {2012}, pages = {78--94}, journal = {Palaeogeography Palaeoclimatology Palaeoecology}, keywords = {Eocene, Southern Ocean, Middle Eocene Climatic Optimum, Ebridians, Silicoflagellates, Diatoms, Ocean Drilling Program}, url = {https://eprints.soton.ac.uk/337101/}, abstract = {The Middle Eocene Climatic Optimum (MECO) is a major transient warming event that occurred at {\texttt{\char126}} 40 Ma and reversed a long-term cooling trend through the early and middle Eocene. We report the results of a high-resolution, quantitative study of siliceous microfossils at Ocean Drilling Program Sites 748 and 749 (Southern Kerguelen Plateau, Southern Ocean, {\texttt{\char126}} 58?S) across a {\texttt{\char126}} 1.4 myr interval spanning the MECO event. At both sites, a significant increase in biosiliceous sedimentation is associated with the MECO event. Rich siliceous planktonic microfossil assemblages in this interval are unusual in that they are dominated by ebridians, with radiolarians as a secondary major component. Silicoflagellates and diatoms comprise only a minor fraction of the assemblage, in contrast to siliceous microfossil assemblages that characterize modern Southern Ocean sediments. Based on our new siliceous microfossil records, we interpret two {\texttt{\char126}} 300 kyr periods of elevated nutrient availability in Southern Ocean surface waters which span the peak warming interval of the MECO and the post-MECO cooling interval. A diverse assemblage of large silicoflagellates belonging to the Dictyocha grandis plexus is linked to the rapid rise in sea-surface temperatures immediately prior to peak warmth, and a pronounced turnover is observed in both ebridian and silicoflagellate assemblages at the onset of peak warming. The interval of peak warmth is also characterized by high abundance of cosmopolitan ebridians (e.g., Ammodochium spp.) and silicoflagellates (e.g., Naviculopsis spp.), and increased abundance of tropical and subtropical diatom genera (e.g., Asterolampra and Azpeitia). These observations confirm the relative pattern of temperature change interpreted from geochemical proxy data at multiple Southern Ocean sites. Furthermore, rapid assemblage changes in both autotrophic and heterotrophic siliceous microfossil groups indicate a reorganization of Southern Ocean plankton communities in response to greenhouse warming during the MECO event.} } @article{soton418084, month = {February}, title = {No change in Southern Ocean circulation in the Indian Ocean from the Eocene through Late Oligocene}, author = {Nicky M. Wright and Howie D. Scher and Maria Seton and Claire E. Huck and Brian D. Duggan}, year = {2018}, journal = {Paleoceanography and Paleoclimatology}, keywords = {Eocene-Oligocene transition, Kerguelen Plateau, Neodymium isotopes, Southern Ocean}, url = {https://eprints.soton.ac.uk/418084/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Deciphering the evolution of Southern Ocean circulation during the Eocene and Oligocene has important implications for understanding the development of the Antarctic Circumpolar Current and transition to Earth's "icehouse" climate. To better understand ocean circulation patterns in the Indian Ocean sector of the Southern Ocean, we generated a new fossil fish tooth neodymium isotope record ({\ensuremath{\epsilon}}{\ensuremath{<}}sub{\ensuremath{>}}Nd{\ensuremath{<}}/sub{\ensuremath{>}}) from the upper Eocene to upper Oligocene sections (36-23 Ma) of Ocean Drilling Program Sites 744 and 748 (Kerguelen Plateau, Indian Ocean). Reconstructed seawater {\ensuremath{\epsilon}}{\ensuremath{<}}sub{\ensuremath{>}}Nd{\ensuremath{<}}/sub{\ensuremath{>}} values from fossil fish teeth are used to trace changes in water masses across ocean basins. The records from Site 748 and Site 744 reveal a gradual shift from {\ensuremath{\epsilon}}{\ensuremath{<}}sub{\ensuremath{>}}Nd{\ensuremath{<}}/sub{\ensuremath{>}} values around -6.5 to -7.5 in the late Eocene to {\ensuremath{\epsilon}}{\ensuremath{<}}sub{\ensuremath{>}}Nd{\ensuremath{<}}/sub{\ensuremath{>}} values between -7.5 and -8.3 by the late Oligocene, consistent with a Circumpolar Deep Water (CDW) influence at the Kerguelen Plateau throughout the Oligocene. We interpret the shift to less radiogenic values to reflect the increased export of Northern Component Water to the Southern Ocean, likely into the proto-CDW. However, the records show no major change in water mass composition around the Kerguelen Plateau that would accompany an increase in Pacific throughflow related to the opening of Drake Passage and imply that Pacific throughflow via the Drake Passage occurred by the late Eocene. High-frequency variability in e{\ensuremath{<}}sub{\ensuremath{>}}Nd{\ensuremath{<}}/sub{\ensuremath{>}} values at Site 744 is interpreted as an imprint of Oligocene glacial activity, with a particularly pronounced excursion at 32.6 Ma roughly coinciding with other glacial weathering indicators around Antarctica.{\ensuremath{<}}/p{\ensuremath{>}}} } @techreport{soton71791, month = {December}, type = {Project Report}, title = {RRS James Clark Ross Cruise 195, 18-29 Nov 2009. Drake Passage repeat hydrography of WOCE section SR1b: a beginners? guide}, author = {M.J. Yelland}, publisher = {National Oceanography Centre}, year = {2009}, series = {45}, keywords = {Antarctic Circumpolar Current, Antarctic Ocean, ADCP, Acoustic Doppler Current Profiler, Cruise 195 2009, CTD Observations, Drake Passage, James Clark Ross, Lowered ADCP, LADCP, Southern Ocean, SR1b, Vessel-Mounted ADCP, WOCE, World Ocean Circulation Experiment}, url = {https://eprints.soton.ac.uk/71791/}, abstract = {This report describes the 16th occupation of the Drake Passage CTD section, established during{\ensuremath{<}}br/{\ensuremath{>}}the World Ocean Circulation Experiment as repeat section SR1b. It was first occupied by{\ensuremath{<}}br/{\ensuremath{>}}National Oceanography Centre (previously IOSDL and then SOC) in collaboration with the{\ensuremath{<}}br/{\ensuremath{>}}British Antarctic Survey in 1993, and has been re-occupied most years since then. Thirty one{\ensuremath{<}}br/{\ensuremath{>}}full depth stations were performed during JR195: two test stations, and 29 of the 30 nominal{\ensuremath{<}}br/{\ensuremath{>}}stations for the SR1b Drake Passage section. Two 500 m stations were added as part of POL's{\ensuremath{<}}br/{\ensuremath{>}}cruise JR198.{\ensuremath{<}}br/{\ensuremath{>}}The CTD was an underwater SBE 9 plus unit equipped with the following sensors: dual{\ensuremath{<}}br/{\ensuremath{>}}temperature and conductivity sensors, a pressure sensor encased in the SBE underwater unit, a{\ensuremath{<}}br/{\ensuremath{>}}SBE-43 oxygen probe, an Aquatracka MKIII fluorometer, a transmissometer, an upwardlooking{\ensuremath{<}}br/{\ensuremath{>}}downwelling PAR sensor, and an altimeter. A downward-looking LADCP (RDI{\ensuremath{<}}br/{\ensuremath{>}}Workhorse Monitor 300 kHz) was deployed on all stations, except for the two 500 m stations{\ensuremath{<}}br/{\ensuremath{>}}when it was replaced by a 600 kHz LADCP from Bangor University.{\ensuremath{<}}br/{\ensuremath{>}}Various underway measurements were obtained, including navigation, VM-ADCP, sea surface{\ensuremath{<}}br/{\ensuremath{>}}temperature and salinity, water depth and various meteorological parameters.} } @techreport{soton208991, month = {December}, author = {M.J. Yelland and et al}, series = {10}, note = {New series incorporating reports from NOC Liverpool and Southampton Sites}, title = {RRS James Clark Ross Cruises JR265 and JR254D, 27 Nov-24 Dec 2011. Part 1: The Drake Passage hydrographic repeat section SR1b}, type = {Project Report}, publisher = {National Oceanography Centre}, year = {2011}, keywords = {Acoustic Doppler Current Profiler, ADCP, air-sea flux, Antarctic Circumpolar Current, cruise 265 2011, CTD observations, Drake Passage, gas exchange, James Clark Ross, JR265, LADCP, lowered ADCP, sea-spray aerosol, SOLAS, Southern Ocean, SR1b, Valkyrie, vessel-mounted ADCP, WAGES, wave breaking, waves, whitecap, WOCE, World OceanCirculation Experiment}, url = {https://eprints.soton.ac.uk/208991/}, abstract = {This report describes the 17th complete occupation of the Drake Passage CTD section, established during the World Ocean Circulation Experiment as repeat section SR1b. It was{\ensuremath{<}}br/{\ensuremath{>}}first occupied by National Oceanography Centre (previously IOSDL and then SOC) in collaboration with the British Antarctic Survey in 1993, and has been re-occupied most years since then. Thirty two full depth stations were performed during JR265: two test stations, and all 30 of the nominal stations for the SR1b Drake Passage section. An initial result is that the estimated total transport measured across the section was 133 Sv which compares well to an average transport measured from the 16 previous UK cruises of 135 Sv (standard deviation of 7 Sv). {\ensuremath{<}}br/{\ensuremath{>}}{\ensuremath{<}}br/{\ensuremath{>}}In conjunction with the hydrographic cruise, a "Waves Aerosol and Gas Exchange Study" (WAGES) intensive observation cruise JR245D was also carried out. WAGES involves continuous measurement of the air-sea turbulent fluxes of CO2, sea spray aerosol, momentum and sensible and latent heat fluxes, plus directional sea-state and whitecap parameters using systems installed on the ship in May 2010. In addition to the continuous measurements, a number of intensive observation periods (IOPs) have been carried out by WAGES staff on board the ship. These involve deployments of a spar buoy to measure wave breaking and an aerial camera system to measure whitecap fraction. The activities of JR254D are summarised here, but are described in detail in a separate cruise report. Cruise JR264 was carried out by NOC-L staff at the same time as JR265 and JR254D. JR264 is also the subject of a separate cruise report. {\ensuremath{<}}br/{\ensuremath{>}}{\ensuremath{<}}br/{\ensuremath{>}}The CTD was an underwater SBE 9 plus unit equipped with the following sensors: dual temperature and conductivity sensors, a pressure sensor encased in the SBE underwater unit, a SBE-43 oxygen probe, an Aquatracka MKIII fluorometer, a transmissometer, an upwardlooking downwelling PAR sensor, and an altimeter. A downward-looking LADCP (RDI Workhorse Monitor 300 kHz) was deployed on all stations. Various underway measurements were obtained, including navigation, VM-ADCP, sea surface temperature and salinity, water depth and various meteorological parameters. A practical aim during this cruise was to update the detailed guides for each of the hydrographic data streams which were first written during{\ensuremath{<}}br/{\ensuremath{>}}JR195 in 2009. The hydrographic data analysis was performed using "MSTAR", a suite of Matlab programs developed at NOCS by Brian King and used on the JCR for the first time during JR195.} } @article{soton448924, volume = {26}, number = {15}, month = {August}, author = {Jane L. Younger and Gemma V. Clucas and Damian Kao and Alex D. Rogers and Karim Gharbi and Tom Hart and Karen J. Miller}, title = {The challenges of detecting subtle population structure and its importance for the conservation of emperor penguins}, journal = {Molecular Ecology}, pages = {3883--3897}, year = {2017}, keywords = {Antarctica, dispersal, population genomics, RAD-seq, Ross Sea, Southern Ocean}, url = {https://eprints.soton.ac.uk/448924/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}Understanding the boundaries of breeding populations is of great importance for conservation efforts and estimates of extinction risk for threatened species. However, determining these boundaries can be difficult when population structure is subtle. Emperor penguins are highly reliant on sea ice, and some populations may be in jeopardy as climate change alters sea-ice extent and quality. An understanding of emperor penguin population structure is therefore urgently needed. Two previous studies have differed in their conclusions, particularly whether the Ross Sea, a major stronghold for the species, is isolated or not. We assessed emperor penguin population structure using 4,596 genome-wide single nucleotide polymorphisms (SNPs), characterized in 110 individuals (10?16 per colony) from eight colonies around Antarctica. In contrast to a previous conclusion that emperor penguins are panmictic around the entire continent, we find that emperor penguins comprise at least four metapopulations, and that the Ross Sea is clearly a distinct metapopulation. Using larger sample sizes and a thorough assessment of the limitations of different analytical methods, we have shown that population structure within emperor penguins does exist and argue that its recognition is vital for the effective conservation of the species. We discuss the many difficulties that molecular ecologists and managers face in the detection and interpretation of subtle population structure using large SNP data sets, and argue that subtle structure should be taken into account when determining management strategies for threatened species, until accurate estimates of demographic connectivity among populations can be made.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton453803, month = {November}, title = {Timing and tectonic setting of tin mineralization in southern Myanmar: constraints from cassiterite and wolframite U?Pb ages}, author = {Qiang Zhang and Kui-dong Zhao and Wen-qian Li and Martin R. Palmer and Shao-yong Jiang and Hai Jiang and Wei Zhang and Di Zhang and Amjad Hussain}, year = {2021}, note = {Funding Information: This study is supported by the National Natural Science Foundation of China Project (No. 91755208, No. 41673043) and the National Key R \& D Plan (No. 2017YFC0601404). Publisher Copyright: {\copyright} 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature. Copyright: Copyright 2021 Elsevier B.V., All rights reserved.}, journal = {Mineralium Deposita}, keywords = {Cassiterite, Southeast Asia tin belt, Southern Myanmar, Tin deposits, U?Pb geochronology, Wolframite}, url = {https://eprints.soton.ac.uk/453803/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}The southern Myanmar tin ore district is an important part of the well-known Southeast Asia tin belt (SATB), and hosts numerous economically important primary tin-tungsten ore deposits. However, the timing of formation of these deposits is unclear due to the scarcity of robust age data. The tectonic setting of tin mineralization in this area also needs to be further constrained. Most of the primary tin-tungsten ore deposits in southern Myanmar are typical hydrothermal quartz vein?type, with cassiterite and wolframite as the main ore minerals. Here, we present in situ U?Pb ages of cassiterite and wolframite from nine granite-related hydrothermal Sn?W deposits in southern Myanmar. Cassiterite samples from the Hermyingyi, Thitkhatoe, Thaling Taung, Kalonta, Taungphila, Pagaye, Bawapin, Kanbauk, and Letha Taung deposits yield common lead-corrected weighted mean {\ensuremath{<}}sup{\ensuremath{>}}206{\ensuremath{<}}/sup{\ensuremath{>}}Pb/ {\ensuremath{<}}sup{\ensuremath{>}}238{\ensuremath{<}}/sup{\ensuremath{>}}U ages of 61.6 {$\pm$} 0.8 Ma, 61.9 {$\pm$} 0.6 Ma, 60.4 {$\pm$} 0.9 Ma, 63.0 {$\pm$} 0.6 Ma, 62.9 {$\pm$} 0.6 Ma, 69.5 {$\pm$} 0.5 Ma, 63.6 {$\pm$} 0.6 Ma, 61.3 {$\pm$} 0.6 Ma, and 84.9 {$\pm$} 0.5 Ma, respectively. Wolframite samples collected from these deposits also yield consistent ages with the cassiterite samples. These ages, combined with available tin mineralization ages from other deposits in the western part of the SATB, define three epochs of Sn metallogeny related to three contrasting geodynamic settings: (1) Early Cretaceous ({\texttt{\char126}} 125?110 Ma) mineralization is related to post-collision slab break-off after collision between the West Burma terrane and the Sibumasu-Tengchong terrane; (2) Late Cretaceous to Paleocene ({\texttt{\char126}} 90?60 Ma) mineralization developed in an Andean-type accretionary setting during subduction of the Neo-Tethys oceanic lithosphere; (3) Early Eocene ({\texttt{\char126}} 50?40 Ma) mineralization may have formed in a post-collision setting after the India-Asia collision. {\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton353984, volume = {43}, number = {5}, month = {May}, author = {Jan D. Zika and Julien Le Sommer and Carolina O. Dufour and Jean-Marc Molines and Bernard Barnier and Pierre Brasseur and Rapha{\"e}l Dussin and Thierry Penduff and Daniele Iudicone and Andrew Lenton and Gurvan Madec and Pierre Mathiot and James Orr and Emily Shuckburgh and Frederic Vivier}, title = {Vertical Eddy Fluxes in the Southern Ocean}, journal = {Journal of Physical Oceanography}, pages = {941--955}, year = {2013}, keywords = {Southern Ocean, Density currents, Eddies, Meridional overturning circulation, Upwelling/downwelling, Coordinate systems}, url = {https://eprints.soton.ac.uk/353984/}, abstract = {The overturning circulation of the Southern Ocean has been investigated using eddying coupled ocean?sea ice models. The circulation is diagnosed in both density?latitude coordinates and in depth?density coordinates. Depth?density coordinates follow streamlines where the Antarctic Circumpolar Current is equivalent barotropic, capture the descent of Antarctic Bottom Water, follow density outcrops at the surface, and can be interpreted energetically. In density?latitude coordinates, wind-driven northward transport of light water and southward transport of dense water are compensated by standing meanders and to a lesser degree by transient eddies, consistent with previous results. In depth?density coordinates, however, wind-driven upwelling of dense water and downwelling of light water are compensated more strongly by transient eddy fluxes than fluxes because of standing meanders. Model realizations are discussed where the wind pattern of the southern annular mode is amplified. In density?latitude coordinates, meridional fluxes because of transient eddies can increase to counter changes in Ekman transport and decrease in response to changes in the standing meanders. In depth?density coordinates, vertical fluxes because of transient eddies directly counter changes in Ekman pumping.} } @article{soton337462, volume = {39}, number = {11}, month = {November}, author = {Jan D. Zika and Bernadette M. Sloyan and Trevor J. McDougall}, title = {Diagnosing the Southern Ocean Overturning from Tracer Fields}, journal = {Journal of Physical Oceanography}, pages = {2926--2940}, year = {2009}, keywords = {Southern Ocean, Ocean circulation, Meridional Overturning Circulation, Tracers, Southern Hemisphere}, url = {https://eprints.soton.ac.uk/337462/}, abstract = {The strength and structure of the Southern Hemisphere meridional overturning circulation (SMOC) is related to the along-isopycnal and vertical mixing coefficients by analyzing tracer and density fields from a hydrographic climatology. The meridional transport of Upper Circumpolar Deep Water (UCDW) across the Antarctic Circumpolar Current (ACC) is expressed in terms of the along-isopycnal (K) and diapycnal (D) tracer diffusivities and in terms of the along-isopycnal potential vorticity mixing coefficient (KPV). Uniform along-isopycnal (\<600 m2 s?1) and low vertical mixing (10?5 m2 s?1) can maintain a southward transport of less than 60 Sv (Sv = 106 m2 s?1) of UCDW across the ACC, which is distributed largely across the South Pacific and east Indian Ocean basins. For vertical mixing rates of O(10?4 m2 s?1) or greater, the inferred transport is significantly enhanced. The transports inferred from both tracer and density distributions suggest a ratio K to D of O(2 {$\times$} 106) particularly on deeper layers of UCDW. Given the range of observed southward transports of UCDW, it is found that K = 300 {$\pm$} 150 m2 s?1 and D = 10?4 {$\pm$} 0.5 {$\times$} 10?4 m2 s?1 in the Southern Ocean interior. A view of the SMOC is revealed where dense waters are converted to lighter waters not only at the ocean surface, but also on depths below that of the mixed layer with vertical mixing playing an important role.} } @article{soton49516, volume = {54}, number = {18-20}, title = {Microbial abundance, activity and iron uptake in vicinity of the Crozet Isles in November 2004-January 2005}, author = {M.V. Zubkov and R.J. Holland and P.H. Burkill and I.W. Croudace and P.E. Warwick}, year = {2007}, pages = {2126--2137}, journal = {Deep Sea Research Part II: Topical Studies in Oceanography}, keywords = {Ultraplankton, Microbial bioassay, Bacterioplankton production, Iron tracer uptake, Southern Ocean, HNLC regions}, url = {https://eprints.soton.ac.uk/49516/}, abstract = {Iron leached from volcanic islands was hypothesised to naturally fertilise the high-nutrient low-chlorophyll (HNLC) waters of the Antarctic Circum Polar Current and to cause recurrent phytoplankton blooms or high-chlorophyll (HC) areas in the wake of the Crozet Islands. As part of CROZEX, the effect of Fe-fertilisation on microbial community was examined by comparing microbial standing stocks and microbial turnover rates of dissolved organic molecules and iron in the HNLC and HC waters in the vicinity of the Crozet Isles. Bacterioplankton and ultraplanktonic algae were enumerated by flow cytometry. Microbial turnover and ambient concentrations of amino acids and glucose in surface waters were bioassayed using an isotopic dilution technique. Microbial uptake of iron was estimated using a carrier-free 55Fe tracer approach. The data set generated did not reveal statistically significant seasonal changes above the observed high spatial variability in the studied area. Statistically significant higher biomass (1.5 times) of heterotrophic bacterioplankton (HB) as well as higher microbial turnover of organic molecules (10 times) were observed in the HC waters relative to the HNLC waters, while relative iron uptake was nearly eight times lower in the HC waters. However, the difference in HB standing stocks in the 100?200 m water layer between the two compared water types was statistically insignificant. Hence, the HC surface waters in austral summer showed higher microbial activity with decreased iron dependency relative to the HNLC waters of the Southern Ocean, in agreement with higher productivity of the waters to the north of the Crozet Islands.} } @article{soton41431, volume = {110}, number = {C9}, title = {Synthesis of iron fertilization experiments: From the Iron Age in the Age of Enlightenment}, author = {Hein J.W. de Baar and Philip W. Boyd and Kenneth H. Coale and Michael R. Landry and Atsushi Tsuda and Philipp Assmy and Dorothee C.E. Bakker and Yann Bozec and Richard T. Barber and Mark A. Brzezinski and Ken O. Buesseler and Marie Boye and Peter L. Croot and Frank Gervais and Maxim Y. Gorbunov and Paul J. Harrison and William T. Hiscock and Patrick Laan and Christiane Lancelot and Cliff S. Law and Maurice Levasseur and Adrian Marchetti and Frank J. Millero and Jun Nishioka and Yukihiro Nojiri and Tim van Oijen and Ulf Riebesell and Micha J.A. Rijkenberg and Hiroaki Saito and Shigenobu Takeda and Klaas R. Timmermans and Marcel J.W. Veldhuis and Anya M. Waite and Chi-Shing Wong}, year = {2005}, pages = {C09S16}, journal = {Journal of Geophysical Research}, keywords = {equatorial Pacific Ocean, release experiment soiree, sub-Arctic Pacific, Austral spring 1992, open Southern Ocean, phytoplankton growth, enrichment experiment, experiment SOFEX, sulfur hexafluoride, carbon dioxide}, url = {https://eprints.soton.ac.uk/41431/}, abstract = {Comparison of eight iron experiments shows that maximum Chl a, the maximum DIC removal, and the overall DIC/ Fe efficiency all scale inversely with depth of the wind mixed layer (WML) defining the light environment. Moreover, lateral patch dilution, sea surface irradiance, temperature, and grazing play additional roles. The Southern Ocean experiments were most influenced by very deep WMLs. In contrast, light conditions were most favorable during SEEDS and SERIES as well as during IronEx-2. The two extreme experiments, EisenEx and SEEDS, can be linked via EisenEx bottle incubations with shallower simulated WML depth. Large diatoms always benefit the most from Fe addition, where a remarkably small group of thriving diatom species is dominated by universal response of Pseudo-nitzschia spp. Significant response of these moderate ( 10 - 30 mu m), medium ( 30 - 60 mu m), and large (\> 60 mu m) diatoms is consistent with growth physiology determined for single species in natural seawater. The minimum level of "dissolved'' Fe ( filtrate \< 0.2 mu m) maintained during an experiment determines the dominant diatom size class. However, this is further complicated by continuous transfer of original truly dissolved reduced Fe(II) into the colloidal pool, which may constitute some 75\% of the "dissolved'' pool. Depth integration of carbon inventory changes partly compensates the adverse effects of a deep WML due to its greater integration depths, decreasing the differences in responses between the eight experiments. About half of depth-integrated overall primary productivity is reflected in a decrease of DIC. The overall C/Fe efficiency of DIC uptake is DIC/Fe similar to 5600 for all eight experiments. The increase of particulate organic carbon is about a quarter of the primary production, suggesting food web losses for the other three quarters. Replenishment of DIC by air/sea exchange tends to be a minor few percent of primary CO2 fixation but will continue well after observations have stopped. Export of carbon into deeper waters is difficult to assess and is until now firmly proven and quite modest in only two experiments.} } @article{soton422422, volume = {492}, month = {June}, title = {On the origin of the marine zinc?silicon correlation}, author = {Gregory F. de Souza and Samar P. Khatiwala and Mathis P. Hain and Susan H. Little and Derek Vance}, year = {2018}, pages = {22--34}, journal = {Earth and Planetary Science Letters}, keywords = {diatoms, GEOTRACES, ocean biogeochemistry, Southern Ocean}, url = {https://eprints.soton.ac.uk/422422/}, abstract = {{\ensuremath{<}}p{\ensuremath{>}}The close linear correlation between the distributions of dissolved zinc (Zn) and silicon (Si) in seawater has puzzled chemical oceanographers since its discovery almost forty years ago, due to the apparent lack of a mechanism for coupling these two nutrient elements. Recent research has shown that such a correlation can be produced in an ocean model without any explicit coupling between Zn and Si, via the export of Zn-rich biogenic particles in the Southern Ocean, consistent with the observation of elevated Zn quotas in Southern Ocean diatoms. Here, we investigate the physical and biological mechanisms by which Southern Ocean uptake and export control the large-scale marine Zn distribution, using suites of sensitivity simulations in an ocean general circulation model (OGCM) and a box-model ensemble. These simulations focus on the sensitivity of the Zn distribution to the stoichiometry of Zn uptake relative to phosphate (PO{\ensuremath{<}}sub{\ensuremath{>}}4{\ensuremath{<}}/sub{\ensuremath{>}}), drawing directly on observations in culture. Our analysis reveals that OGCM model variants that produce a well-defined step between relatively constant, high Zn:PO{\ensuremath{<}}sub{\ensuremath{>}}4{\ensuremath{<}}/sub{\ensuremath{>}} uptake ratios in the Southern Ocean and low Zn:PO{\ensuremath{<}}sub{\ensuremath{>}}4{\ensuremath{<}}/sub{\ensuremath{>}} ratios at lower latitudes fare best in reproducing the marine Zn?Si correlation at both the global and the regional Southern Ocean scale, suggesting the presence of distinct Zn-biogeochemical regimes in the high- and low-latitude oceans that may relate to differences in physiology, ecology or (micro-)nutrient status. Furthermore, a study of the systematics of both the box model and the OGCM reveals that regional Southern Ocean Zn uptake exerts control over the global Zn distribution via its modulation of the biogeochemical characteristics of the surface Southern Ocean. Specifically, model variants with elevated Southern Ocean Zn:PO{\ensuremath{<}}sub{\ensuremath{>}}4{\ensuremath{<}}/sub{\ensuremath{>}} uptake ratios produce near-complete Zn depletion in the Si-poor surface Subantarctic Zone, where upper-ocean water masses with key roles in the global oceanic circulation are formed. By setting the main preformed covariation trend within the ocean interior, the subduction of these Zn- and Si-poor water masses produces a close correlation between the Zn and Si distributions that is barely altered by their differential remineralisation during low-latitude cycling. We speculate that analogous processes in the high-latitude oceans may operate for other trace metal micronutrients as well, splitting the ocean into two fundamentally different biogeochemical, and thus biogeographic, regimes.{\ensuremath{<}}/p{\ensuremath{>}}} } @article{soton385962, volume = {26}, number = {3}, month = {March}, author = {S. van Bellen and D. Mauquoy and P. Hughes and T.P. Roland and T.J. Daley and N.J. Loader and F.A. Street-Perrott and E.M. Rice and V.A. Pancotto and R.J. Payne}, title = {Late-Holocene climate dynamics recorded in the peat bogs of Tierra del Fuego, South America}, journal = {The Holocene}, pages = {489--501}, year = {2016}, keywords = {assulina muscorum, palaeoSig, patagonia, southern annular mode, southern westerly wind, uv-B}, url = {https://eprints.soton.ac.uk/385962/}, abstract = {The ombrotrophic peat bogs of Tierra del Fuego are located within the southern westerly wind belt (SWWB), which dominates climate variability in this region. We have reconstructed late-Holocene water-table depths from three peat bogs and aimed to relate these records to shifts in regional climate. Water-table depths were quantified by the analysis of testate amoeba assemblages, and a regional transfer function was used to infer past water-table depths. During the last 2000?years, testate amoeba assemblages have been relatively stable, with a dominance of Difflugia pulex and Difflugia pristis type, and an increase in Assulina muscorum and other Euglyphida at the top of each section. Multivariate analyses show that water-table depth remained the main environmental variable explaining assemblages along the TiA12 core, but reconstructions were not significant for the two other cores. In line with the low variability in assemblages, water tables were relatively stable during the last 2000?years. Slightly wetter conditions were found between {\texttt{\char126}}1400 and 900 cal. BP and a pronounced recent dry shift was reconstructed in all of the three peat profiles. Considering the regional climatic context, this recent shift may have been forced by a decrease in precipitation and warmer conditions linked to an increase in the importance of the SWWB. Nevertheless, we cannot exclude the influence of higher UV-B radiation resulting from the local degradation of the ozone layer since the late 1970s, which may have had an additional effect on the relative presence of A. muscorum in the southern Patagonian region.} } @article{soton368654, volume = {81}, month = {September}, title = {A realistic freshwater forcing protocol for ocean-coupled climate models}, author = {J. van den Berk and S.S. Drijfhout}, year = {2014}, pages = {36--48}, journal = {Ocean Modelling}, keywords = {Surface freshwater flux, Global ocean model, North Atlantic, Southern ocean}, url = {https://eprints.soton.ac.uk/368654/}, abstract = {A high-end scenario of polar ice loss from the Greenland and Antarctic ice sheet is presented with separate projections for different mass-loss sites up to the year 2100. For each large ice sheet three potential sources of freshwater release to the ocean are considered: run-off from surface melt, basal melt through heat exchange with the ocean, and iceberg calving and subsequent mass loss through melt of drifting icebergs. The location and relative magnitude of freshwater forcing due to drifting icebergs is calculated from a separate iceberg drift simulation. We assume fixed annual spatial patterns with magnitudes varying in time. These magnitudes are based on a severe warming scenario based on expert elicitation. The resultant freshwater forcing is applied to a global climate model and the effects on sea-level rise are discussed. The simulations show strong sea level rise on the Antarctic continental shelves. The effect on the Atlantic overturning circulation is very small, however.} }