Distinct roles of the Southern Ocean and North Atlantic in the deglacial atmospheric radiocarbon decline
Distinct roles of the Southern Ocean and North Atlantic in the deglacial atmospheric radiocarbon decline
In the context of the atmospheric CO214C/C (?Catm14) changes since the last ice age, two episodes of sharp ?Catm14 decline have been related to either the venting of deeply sequestered low-14C CO2 through the Southern Ocean surface or the abrupt onset of North Atlantic Deep Water (NADW) formation. In model simulations using an improved reconstruction of 14C production, Atlantic circulation change and Southern Ocean CO2 release both contribute to the overall deglacial ?Catm14 decline, but only the onset of NADW can reproduce the sharp ?Catm14 declines. To fully simulate ?Catm14 data requires an additional process that immediately precedes the onsets of NADW. We hypothesize that these “early” ?Catm14 declines record the thickening of the ocean's thermocline in response to reconstructed transient shutdown of NADW and/or changes in the southern hemisphere westerly winds. Such thermocline thickening may have played a role in triggering the NADW onsets.
198-208
Hain, Mathis P.
d31486bc-c473-4c34-a814-c0834640876c
Sigman, Daniel M.
b7945f7b-3945-4082-9204-feb1eb8cfed7
Haug, Gerald H.
b6d161a0-4bdc-44d3-8a88-8de0e3517ca8
15 May 2014
Hain, Mathis P.
d31486bc-c473-4c34-a814-c0834640876c
Sigman, Daniel M.
b7945f7b-3945-4082-9204-feb1eb8cfed7
Haug, Gerald H.
b6d161a0-4bdc-44d3-8a88-8de0e3517ca8
Hain, Mathis P., Sigman, Daniel M. and Haug, Gerald H.
(2014)
Distinct roles of the Southern Ocean and North Atlantic in the deglacial atmospheric radiocarbon decline.
Earth and Planetary Science Letters, 394, .
(doi:10.1016/j.epsl.2014.03.020).
Abstract
In the context of the atmospheric CO214C/C (?Catm14) changes since the last ice age, two episodes of sharp ?Catm14 decline have been related to either the venting of deeply sequestered low-14C CO2 through the Southern Ocean surface or the abrupt onset of North Atlantic Deep Water (NADW) formation. In model simulations using an improved reconstruction of 14C production, Atlantic circulation change and Southern Ocean CO2 release both contribute to the overall deglacial ?Catm14 decline, but only the onset of NADW can reproduce the sharp ?Catm14 declines. To fully simulate ?Catm14 data requires an additional process that immediately precedes the onsets of NADW. We hypothesize that these “early” ?Catm14 declines record the thickening of the ocean's thermocline in response to reconstructed transient shutdown of NADW and/or changes in the southern hemisphere westerly winds. Such thermocline thickening may have played a role in triggering the NADW onsets.
This record has no associated files available for download.
More information
Accepted/In Press date: 10 March 2014
e-pub ahead of print date: 3 April 2014
Published date: 15 May 2014
Organisations:
Paleooceanography & Palaeoclimate
Identifiers
Local EPrints ID: 364156
URI: http://eprints.soton.ac.uk/id/eprint/364156
ISSN: 0012-821X
PURE UUID: a6fe43f3-b314-43d3-8cbb-57206089f816
Catalogue record
Date deposited: 07 Apr 2014 09:59
Last modified: 14 Mar 2024 16:31
Export record
Altmetrics
Contributors
Author:
Daniel M. Sigman
Author:
Gerald H. Haug
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