Coupled atmosphere-ocean response of the southwest Pacific to deglacial changes in Atlantic meridional overturning circulation

The last glacial termination was characterised by millennial-scale episodes of warming and cooling that appear offset between the hemispheres. It has been proposed that this bi-polar seesaw is the result of climate system feedbacks. A key debate, which remains unresolved, concerns the relative roles...

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Published in:Earth and Planetary Science Letters
Main Authors: Eaves, Shaun R., Mackintosh, Andrew N., Pedro, Joel B., Bostock, Helen C., Ryan, Matthew T., Norton, Kevin P., Hayward, Bruce W., Anderson, Brian M., He, Feng, Jones, Richard S., Lorrey, Andrew M., Newnham, Rewi M., Tims, Stephen G., Vandergoes, Marcus J.
Format: Article in Journal/Newspaper
Language:English
Published: Elsevier BV 2024
Subjects:
Online Access:https://archimer.ifremer.fr/doc/00893/100533/110959.pdf
https://archimer.ifremer.fr/doc/00893/100533/110960.docx
https://doi.org/10.1016/j.epsl.2024.118802
https://archimer.ifremer.fr/doc/00893/100533/
id ftarchimer:oai:archimer.ifremer.fr:100533
record_format openpolar
spelling ftarchimer:oai:archimer.ifremer.fr:100533 2024-06-23T07:47:09+00:00 Coupled atmosphere-ocean response of the southwest Pacific to deglacial changes in Atlantic meridional overturning circulation Eaves, Shaun R. Mackintosh, Andrew N. Pedro, Joel B. Bostock, Helen C. Ryan, Matthew T. Norton, Kevin P. Hayward, Bruce W. Anderson, Brian M. He, Feng Jones, Richard S. Lorrey, Andrew M. Newnham, Rewi M. Tims, Stephen G. Vandergoes, Marcus J. 2024-09 application/pdf https://archimer.ifremer.fr/doc/00893/100533/110959.pdf https://archimer.ifremer.fr/doc/00893/100533/110960.docx https://doi.org/10.1016/j.epsl.2024.118802 https://archimer.ifremer.fr/doc/00893/100533/ eng eng Elsevier BV https://archimer.ifremer.fr/doc/00893/100533/110959.pdf https://archimer.ifremer.fr/doc/00893/100533/110960.docx doi:10.1016/j.epsl.2024.118802 https://archimer.ifremer.fr/doc/00893/100533/ info:eu-repo/semantics/openAccess restricted use Earth and Planetary Science Letters (0012-821X) (Elsevier BV), 2024-09 , Vol. 641 , P. 118802 (12p.) Mountain glacier Last glacial termination Southern hemisphere Sea surface temperature Bipolar seesaw Southern westerly winds text Article info:eu-repo/semantics/article 2024 ftarchimer https://doi.org/10.1016/j.epsl.2024.118802 2024-06-12T00:05:55Z The last glacial termination was characterised by millennial-scale episodes of warming and cooling that appear offset between the hemispheres. It has been proposed that this bi-polar seesaw is the result of climate system feedbacks. A key debate, which remains unresolved, concerns the relative roles of the atmosphere and oceans in transmitting these climate responses between the hemispheres. In this study we present quantitative climate proxy data to show that air temperatures in New Zealand, as recorded by mountain glaciers, tracked millennial-scale warming and cooling of local surface temperatures of the adjacent Tasman Sea throughout the last glacial termination. Both realms were dominated by warming between 18 ka and 12 ka, interrupted by a multi-centennial to millennial-scale cooling event centred on 14 ka, coincident with the Antarctic Cold Reversal. Reconciling our climate proxy evidence with a transient climate model simulation of the glacial termination, we find that the timing and amplitude of temperature changes are consistent with changing Atlantic meridional overturning circulation (AMOC). The southwest Pacific region displays a particularly sensitive response to AMOC intensity changes, despite its far-field situation from the North Atlantic. This sensitivity represents the combined impact of fast-acting oceanic teleconnections and regional atmosphere-ocean response associated with changes to the southern westerly winds. Our findings highlight that recent hypotheses promoting the role of southern westerlies as a critical component of deglaciation may be complementary to, rather than competitive with, the bipolar seesaw paradigm. Article in Journal/Newspaper Antarc* Antarctic North Atlantic Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer) Antarctic New Zealand Pacific The Antarctic Earth and Planetary Science Letters 641 118802
institution Open Polar
collection Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer)
op_collection_id ftarchimer
language English
topic Mountain glacier
Last glacial termination
Southern hemisphere
Sea surface temperature
Bipolar seesaw
Southern westerly winds
spellingShingle Mountain glacier
Last glacial termination
Southern hemisphere
Sea surface temperature
Bipolar seesaw
Southern westerly winds
Eaves, Shaun R.
Mackintosh, Andrew N.
Pedro, Joel B.
Bostock, Helen C.
Ryan, Matthew T.
Norton, Kevin P.
Hayward, Bruce W.
Anderson, Brian M.
He, Feng
Jones, Richard S.
Lorrey, Andrew M.
Newnham, Rewi M.
Tims, Stephen G.
Vandergoes, Marcus J.
Coupled atmosphere-ocean response of the southwest Pacific to deglacial changes in Atlantic meridional overturning circulation
topic_facet Mountain glacier
Last glacial termination
Southern hemisphere
Sea surface temperature
Bipolar seesaw
Southern westerly winds
description The last glacial termination was characterised by millennial-scale episodes of warming and cooling that appear offset between the hemispheres. It has been proposed that this bi-polar seesaw is the result of climate system feedbacks. A key debate, which remains unresolved, concerns the relative roles of the atmosphere and oceans in transmitting these climate responses between the hemispheres. In this study we present quantitative climate proxy data to show that air temperatures in New Zealand, as recorded by mountain glaciers, tracked millennial-scale warming and cooling of local surface temperatures of the adjacent Tasman Sea throughout the last glacial termination. Both realms were dominated by warming between 18 ka and 12 ka, interrupted by a multi-centennial to millennial-scale cooling event centred on 14 ka, coincident with the Antarctic Cold Reversal. Reconciling our climate proxy evidence with a transient climate model simulation of the glacial termination, we find that the timing and amplitude of temperature changes are consistent with changing Atlantic meridional overturning circulation (AMOC). The southwest Pacific region displays a particularly sensitive response to AMOC intensity changes, despite its far-field situation from the North Atlantic. This sensitivity represents the combined impact of fast-acting oceanic teleconnections and regional atmosphere-ocean response associated with changes to the southern westerly winds. Our findings highlight that recent hypotheses promoting the role of southern westerlies as a critical component of deglaciation may be complementary to, rather than competitive with, the bipolar seesaw paradigm.
format Article in Journal/Newspaper
author Eaves, Shaun R.
Mackintosh, Andrew N.
Pedro, Joel B.
Bostock, Helen C.
Ryan, Matthew T.
Norton, Kevin P.
Hayward, Bruce W.
Anderson, Brian M.
He, Feng
Jones, Richard S.
Lorrey, Andrew M.
Newnham, Rewi M.
Tims, Stephen G.
Vandergoes, Marcus J.
author_facet Eaves, Shaun R.
Mackintosh, Andrew N.
Pedro, Joel B.
Bostock, Helen C.
Ryan, Matthew T.
Norton, Kevin P.
Hayward, Bruce W.
Anderson, Brian M.
He, Feng
Jones, Richard S.
Lorrey, Andrew M.
Newnham, Rewi M.
Tims, Stephen G.
Vandergoes, Marcus J.
author_sort Eaves, Shaun R.
title Coupled atmosphere-ocean response of the southwest Pacific to deglacial changes in Atlantic meridional overturning circulation
title_short Coupled atmosphere-ocean response of the southwest Pacific to deglacial changes in Atlantic meridional overturning circulation
title_full Coupled atmosphere-ocean response of the southwest Pacific to deglacial changes in Atlantic meridional overturning circulation
title_fullStr Coupled atmosphere-ocean response of the southwest Pacific to deglacial changes in Atlantic meridional overturning circulation
title_full_unstemmed Coupled atmosphere-ocean response of the southwest Pacific to deglacial changes in Atlantic meridional overturning circulation
title_sort coupled atmosphere-ocean response of the southwest pacific to deglacial changes in atlantic meridional overturning circulation
publisher Elsevier BV
publishDate 2024
url https://archimer.ifremer.fr/doc/00893/100533/110959.pdf
https://archimer.ifremer.fr/doc/00893/100533/110960.docx
https://doi.org/10.1016/j.epsl.2024.118802
https://archimer.ifremer.fr/doc/00893/100533/
geographic Antarctic
New Zealand
Pacific
The Antarctic
geographic_facet Antarctic
New Zealand
Pacific
The Antarctic
genre Antarc*
Antarctic
North Atlantic
genre_facet Antarc*
Antarctic
North Atlantic
op_source Earth and Planetary Science Letters (0012-821X) (Elsevier BV), 2024-09 , Vol. 641 , P. 118802 (12p.)
op_relation https://archimer.ifremer.fr/doc/00893/100533/110959.pdf
https://archimer.ifremer.fr/doc/00893/100533/110960.docx
doi:10.1016/j.epsl.2024.118802
https://archimer.ifremer.fr/doc/00893/100533/
op_rights info:eu-repo/semantics/openAccess
restricted use
op_doi https://doi.org/10.1016/j.epsl.2024.118802
container_title Earth and Planetary Science Letters
container_volume 641
container_start_page 118802
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