The University of Southampton
University of Southampton Institutional Repository

Precession-driven changes in Iceland–Scotland Overflow Water penetration and bottom water circulation on Gardar Drift since ~200ka

Precession-driven changes in Iceland–Scotland Overflow Water penetration and bottom water circulation on Gardar Drift since ~200ka
Precession-driven changes in Iceland–Scotland Overflow Water penetration and bottom water circulation on Gardar Drift since ~200ka
Benthic foraminiferal stable isotopic records from a transect of sediment cores south of the Iceland–Scotland Ridge reveal that the penetration depth of Iceland–Scotland Overflow Water (ISOW) varied on orbital timescales with precessional pacing over the past ~ 200 kyr. Similar, higher benthic foraminiferal ?13C values (~ 1.0‰) were recorded at all transect sites downstream of the Iceland–Scotland Ridge during interglacial periods (Marine Isotope Chrons 5 and 1), indicating a deeply penetrating ISOW. During glacial periods (Marine Isotope Chrons 6, 4, and 2), benthic foraminiferal ?13C values from the deeper (2700–3300 m), southern sites within this transect were significantly lower (~ 0.5‰) than values from the northern (shallower) portion of the transect (~ 1.0‰), reflecting a shoaling of ISOW and greater influence of glacial Southern Component Water (SCW) in the deep Northeast Atlantic. Particularly during intermediate climate states, ISOW strength is driven by precessional cycles, superimposed on the large-scale glacial–interglacial ISOW variability. Millennial-scale variability in the penetration of ISOW, likely caused by high-frequency Heinrich and Dansgaard–Oeschger events, is most pronounced during intermediate climate states.
North Atlantic Deep Water, Gardar Drift, Insolation
0031-0182
551-563
Elmore, A.C.
47fc0a23-649a-4cd8-b732-fa6cc74ea2d3
Wright, J.D.
20fe2a0a-bfa6-4067-93d9-3713044e84f1
Chalk, T.B.
0021bbe6-6ab1-4a30-8542-654d0f2d1a0a
Elmore, A.C.
47fc0a23-649a-4cd8-b732-fa6cc74ea2d3
Wright, J.D.
20fe2a0a-bfa6-4067-93d9-3713044e84f1
Chalk, T.B.
0021bbe6-6ab1-4a30-8542-654d0f2d1a0a

Elmore, A.C., Wright, J.D. and Chalk, T.B. (2015) Precession-driven changes in Iceland–Scotland Overflow Water penetration and bottom water circulation on Gardar Drift since ~200ka. Palaeogeography, Palaeoclimatology, Palaeoecology, 440, 551-563. (doi:10.1016/j.palaeo.2015.09.042).

Record type: Article

Abstract

Benthic foraminiferal stable isotopic records from a transect of sediment cores south of the Iceland–Scotland Ridge reveal that the penetration depth of Iceland–Scotland Overflow Water (ISOW) varied on orbital timescales with precessional pacing over the past ~ 200 kyr. Similar, higher benthic foraminiferal ?13C values (~ 1.0‰) were recorded at all transect sites downstream of the Iceland–Scotland Ridge during interglacial periods (Marine Isotope Chrons 5 and 1), indicating a deeply penetrating ISOW. During glacial periods (Marine Isotope Chrons 6, 4, and 2), benthic foraminiferal ?13C values from the deeper (2700–3300 m), southern sites within this transect were significantly lower (~ 0.5‰) than values from the northern (shallower) portion of the transect (~ 1.0‰), reflecting a shoaling of ISOW and greater influence of glacial Southern Component Water (SCW) in the deep Northeast Atlantic. Particularly during intermediate climate states, ISOW strength is driven by precessional cycles, superimposed on the large-scale glacial–interglacial ISOW variability. Millennial-scale variability in the penetration of ISOW, likely caused by high-frequency Heinrich and Dansgaard–Oeschger events, is most pronounced during intermediate climate states.

Full text not available from this repository.

More information

Accepted/In Press date: 23 September 2015
Published date: 15 December 2015
Keywords: North Atlantic Deep Water, Gardar Drift, Insolation
Organisations: Geochemistry

Identifiers

Local EPrints ID: 401831
URI: http://eprints.soton.ac.uk/id/eprint/401831
ISSN: 0031-0182
PURE UUID: 1ad3cd64-7355-4166-a68e-efbe5ff9c8af
ORCID for T.B. Chalk: ORCID iD orcid.org/0000-0002-2880-3847

Catalogue record

Date deposited: 20 Oct 2016 09:48
Last modified: 01 Oct 2019 00:28

Export record

Altmetrics

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×