A salty deep ocean as a prerequisite for glacial termination
Deglacial transitions of the middle to late Pleistocene (terminations) are linked to gradual changes in insolation accompanied by abrupt shifts in ocean circulation. However, the reason these deglacial abrupt events are so special compared with their sub-glacial-maximum analogues, in particular with...
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ftawi:oai:epic.awi.de:55092 2023-05-15T13:45:22+02:00 A salty deep ocean as a prerequisite for glacial termination Knorr, Gregor Barker, Stephen Zhang, Xu Lohmann, Gerrit Gong, Xun Gierz, Paul Stepanek, Christian Stap, Lennert B. 2021-12-03 https://epic.awi.de/id/eprint/55092/ https://doi.org/10.1038/s41561-021-00857-3 https://hdl.handle.net/10013/epic.d0fc4dff-4e73-4967-87c2-7ea133735763 unknown NATURE PUBLISHING GROUP Knorr, G. orcid:0000-0002-8317-5046 , Barker, S. , Zhang, X. orcid:0000-0003-1833-9689 , Lohmann, G. orcid:0000-0003-2089-733X , Gong, X. orcid:0000-0001-9308-4431 , Gierz, P. orcid:0000-0002-4512-087X , Stepanek, C. orcid:0000-0002-3912-6271 and Stap, L. B. orcid:0000-0002-2108-3533 (2021) A salty deep ocean as a prerequisite for glacial termination , Nature Geoscience, 14 , pp. 930-936 . doi:10.1038/s41561-021-00857-3 <https://doi.org/10.1038/s41561-021-00857-3> , hdl:10013/epic.d0fc4dff-4e73-4967-87c2-7ea133735763 EPIC3Nature Geoscience, NATURE PUBLISHING GROUP, 14, pp. 930-936, ISSN: 1752-0894 Article isiRev 2021 ftawi https://doi.org/10.1038/s41561-021-00857-3 2022-01-17T00:09:45Z Deglacial transitions of the middle to late Pleistocene (terminations) are linked to gradual changes in insolation accompanied by abrupt shifts in ocean circulation. However, the reason these deglacial abrupt events are so special compared with their sub-glacial-maximum analogues, in particular with respect to the exaggerated warming observed across Antarctica, remains unclear. Here we show that an increase in the relative importance of salt versus temperature stratification in the glacial deep South Atlantic decreases the potential cooling effect of waters that may be upwelled in response to abrupt perturbations in ocean circulation, as compared with sub-glacial-maximum conditions. Using a comprehensive coupled atmosphere–ocean gen-eral circulation model, we then demonstrate that an increase in deep-ocean salinity stratification stabilizes relatively warm waters in the glacial deep ocean, which amplifies the high southern latitude surface ocean temperature response to an abrupt weakening of the Atlantic meridional overturning circulation during deglaciation. The mechanism can produce a doubling in the net rate of warming across Antarctica on a multicentennial timescale when starting from full glacial conditions (as compared with interglacial or subglacial conditions) and therefore helps to explain the large magnitude and rapidity of glacial termina-tions during the late Quaternary. Article in Journal/Newspaper Antarc* Antarctica Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Nature Geoscience 14 12 930 936 |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
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ftawi |
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Deglacial transitions of the middle to late Pleistocene (terminations) are linked to gradual changes in insolation accompanied by abrupt shifts in ocean circulation. However, the reason these deglacial abrupt events are so special compared with their sub-glacial-maximum analogues, in particular with respect to the exaggerated warming observed across Antarctica, remains unclear. Here we show that an increase in the relative importance of salt versus temperature stratification in the glacial deep South Atlantic decreases the potential cooling effect of waters that may be upwelled in response to abrupt perturbations in ocean circulation, as compared with sub-glacial-maximum conditions. Using a comprehensive coupled atmosphere–ocean gen-eral circulation model, we then demonstrate that an increase in deep-ocean salinity stratification stabilizes relatively warm waters in the glacial deep ocean, which amplifies the high southern latitude surface ocean temperature response to an abrupt weakening of the Atlantic meridional overturning circulation during deglaciation. The mechanism can produce a doubling in the net rate of warming across Antarctica on a multicentennial timescale when starting from full glacial conditions (as compared with interglacial or subglacial conditions) and therefore helps to explain the large magnitude and rapidity of glacial termina-tions during the late Quaternary. |
format |
Article in Journal/Newspaper |
author |
Knorr, Gregor Barker, Stephen Zhang, Xu Lohmann, Gerrit Gong, Xun Gierz, Paul Stepanek, Christian Stap, Lennert B. |
spellingShingle |
Knorr, Gregor Barker, Stephen Zhang, Xu Lohmann, Gerrit Gong, Xun Gierz, Paul Stepanek, Christian Stap, Lennert B. A salty deep ocean as a prerequisite for glacial termination |
author_facet |
Knorr, Gregor Barker, Stephen Zhang, Xu Lohmann, Gerrit Gong, Xun Gierz, Paul Stepanek, Christian Stap, Lennert B. |
author_sort |
Knorr, Gregor |
title |
A salty deep ocean as a prerequisite for glacial termination |
title_short |
A salty deep ocean as a prerequisite for glacial termination |
title_full |
A salty deep ocean as a prerequisite for glacial termination |
title_fullStr |
A salty deep ocean as a prerequisite for glacial termination |
title_full_unstemmed |
A salty deep ocean as a prerequisite for glacial termination |
title_sort |
salty deep ocean as a prerequisite for glacial termination |
publisher |
NATURE PUBLISHING GROUP |
publishDate |
2021 |
url |
https://epic.awi.de/id/eprint/55092/ https://doi.org/10.1038/s41561-021-00857-3 https://hdl.handle.net/10013/epic.d0fc4dff-4e73-4967-87c2-7ea133735763 |
genre |
Antarc* Antarctica |
genre_facet |
Antarc* Antarctica |
op_source |
EPIC3Nature Geoscience, NATURE PUBLISHING GROUP, 14, pp. 930-936, ISSN: 1752-0894 |
op_relation |
Knorr, G. orcid:0000-0002-8317-5046 , Barker, S. , Zhang, X. orcid:0000-0003-1833-9689 , Lohmann, G. orcid:0000-0003-2089-733X , Gong, X. orcid:0000-0001-9308-4431 , Gierz, P. orcid:0000-0002-4512-087X , Stepanek, C. orcid:0000-0002-3912-6271 and Stap, L. B. orcid:0000-0002-2108-3533 (2021) A salty deep ocean as a prerequisite for glacial termination , Nature Geoscience, 14 , pp. 930-936 . doi:10.1038/s41561-021-00857-3 <https://doi.org/10.1038/s41561-021-00857-3> , hdl:10013/epic.d0fc4dff-4e73-4967-87c2-7ea133735763 |
op_doi |
https://doi.org/10.1038/s41561-021-00857-3 |
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Nature Geoscience |
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14 |
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12 |
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