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

Shaun R. Eaves; Andrew N. Mackintosh; Joel B. Pedro; Helen C. Bostock; Matthew T. Ryan; Kevin P. Norton; Bruce W. Hayward; Brian M. Anderson; Feng He; Richard S. Jones; Andrew M. Lorrey; Rewi M. Newnham; Stephen G. Tims; Marcus J. Vandergoes

doi:10.1016/j.epsl.2024.118802

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

Shaun R. Eaves
, Andrew N. Mackintosh
, Joel B. Pedro
, Helen C. Bostock
, Matthew T. Ryan
, Kevin P. Norton
, Bruce W. Hayward
, Brian M. Anderson
, Feng He
, Richard S. Jones
, Andrew M. Lorrey
, Rewi M. Newnham
, Stephen G. Tims
, Marcus J. Vandergoes

Research output: Contribution to journal › Article › Research › peer-review

1 Citation (Scopus)

Abstract

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.

Original language	English
Article number	118802
Number of pages	12
Journal	Earth and Planetary Science Letters
Volume	641
DOIs	https://doi.org/10.1016/j.epsl.2024.118802
Publication status	Published - 1 Sept 2024

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

SDG 13 Climate Action

Keywords

Bipolar seesaw
Last glacial termination
Mountain glacier
Sea surface temperature
Southern hemisphere
Southern westerly winds

Access to Document

10.1016/j.epsl.2024.118802Licence: CC BY

Cite this

Eaves, S. R., Mackintosh, A. N., Pedro, J. B., Bostock, H. C., Ryan, M. T., Norton, K. P., Hayward, B. W., Anderson, B. M., He, F., Jones, R. S., Lorrey, A. M., Newnham, R. M., Tims, S. G., & Vandergoes, M. J. (2024). Coupled atmosphere-ocean response of the southwest Pacific to deglacial changes in Atlantic meridional overturning circulation. Earth and Planetary Science Letters, 641, Article 118802. https://doi.org/10.1016/j.epsl.2024.118802

@article{3f575d654d7b41cb9e8691f582051eb9,

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

abstract = "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.",

keywords = "Bipolar seesaw, Last glacial termination, Mountain glacier, Sea surface temperature, Southern hemisphere, Southern westerly winds",

author = "Eaves, \{Shaun R.\} and Mackintosh, \{Andrew N.\} and Pedro, \{Joel B.\} and Bostock, \{Helen C.\} and Ryan, \{Matthew T.\} and Norton, \{Kevin P.\} and Hayward, \{Bruce W.\} and Anderson, \{Brian M.\} and Feng He and Jones, \{Richard S.\} and Lorrey, \{Andrew M.\} and Newnham, \{Rewi M.\} and Tims, \{Stephen G.\} and Vandergoes, \{Marcus J.\}",

note = "Funding Information: This work was funded by a New Zealand Antarctic Research Institute (NZARI), Royal Society of New Zealand Marsden Fund (contract VUW1701 ), Australian Institute of Nuclear Science and Engineering (AINSE) Award No. ALNGRA1116 , and a Leverhulme Study Abroad Studentship. JBP received funding from the Carlsberg Chrono-Climate project and from the Australian Government. ANM and RSJ were partly supported by Australian Research Council (ARC) SRIEAS grant SR200100005 , Securing Antarctica's Environmental Future. We would like to acknowledge Dr Helen Neil at NIWA for access to the MD06-2991 core, which was funded by a joint New Zealand/French collaboration on the RV Marion Dufresne (MATACORE). F.H. was supported by the US NSF ( OPP-1834667 ) and the Climate, People, and the Environment Program. Support for this research was also provided by the University of Wisconsin-Madison Office of the Vice Chancellor for Research and Graduate Education with funding from the Wisconsin Alumni Research Foundation. We would like to acknowledge high-performance computing support from Yellowstone (ark:/85065/d7wd3xhc) and Cheyenne (doi:10.5065/D6RX99HX) provided by NCAR's Computational and Information Systems Laboratory, sponsored by the National Science Foundation. This research used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC05-00OR22725 . Publisher Copyright: {\textcopyright} 2024 The Author(s)",

year = "2024",

month = sep,

day = "1",

doi = "10.1016/j.epsl.2024.118802",

language = "English",

volume = "641",

journal = "Earth and Planetary Science Letters",

issn = "0012-821X",

publisher = "Elsevier BV",

}

Eaves, SR, Mackintosh, AN, Pedro, JB, Bostock, HC, Ryan, MT, Norton, KP, Hayward, BW, Anderson, BM, He, F, Jones, RS, Lorrey, AM, Newnham, RM, Tims, SG & Vandergoes, MJ 2024, 'Coupled atmosphere-ocean response of the southwest Pacific to deglacial changes in Atlantic meridional overturning circulation', Earth and Planetary Science Letters, vol. 641, 118802. https://doi.org/10.1016/j.epsl.2024.118802

TY - JOUR

T1 - Coupled atmosphere-ocean response of the southwest Pacific to deglacial changes in Atlantic meridional overturning circulation

AU - Eaves, Shaun R.

AU - Mackintosh, Andrew N.

AU - Pedro, Joel B.

AU - Bostock, Helen C.

AU - Ryan, Matthew T.

AU - Norton, Kevin P.

AU - Hayward, Bruce W.

AU - Anderson, Brian M.

AU - He, Feng

AU - Jones, Richard S.

AU - Lorrey, Andrew M.

AU - Newnham, Rewi M.

AU - Tims, Stephen G.

AU - Vandergoes, Marcus J.

N1 - Funding Information: This work was funded by a New Zealand Antarctic Research Institute (NZARI), Royal Society of New Zealand Marsden Fund (contract VUW1701 ), Australian Institute of Nuclear Science and Engineering (AINSE) Award No. ALNGRA1116 , and a Leverhulme Study Abroad Studentship. JBP received funding from the Carlsberg Chrono-Climate project and from the Australian Government. ANM and RSJ were partly supported by Australian Research Council (ARC) SRIEAS grant SR200100005 , Securing Antarctica's Environmental Future. We would like to acknowledge Dr Helen Neil at NIWA for access to the MD06-2991 core, which was funded by a joint New Zealand/French collaboration on the RV Marion Dufresne (MATACORE). F.H. was supported by the US NSF ( OPP-1834667 ) and the Climate, People, and the Environment Program. Support for this research was also provided by the University of Wisconsin-Madison Office of the Vice Chancellor for Research and Graduate Education with funding from the Wisconsin Alumni Research Foundation. We would like to acknowledge high-performance computing support from Yellowstone (ark:/85065/d7wd3xhc) and Cheyenne (doi:10.5065/D6RX99HX) provided by NCAR's Computational and Information Systems Laboratory, sponsored by the National Science Foundation. This research used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC05-00OR22725 . Publisher Copyright: © 2024 The Author(s)

PY - 2024/9/1

Y1 - 2024/9/1

N2 - 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.

AB - 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.

KW - Bipolar seesaw

KW - Last glacial termination

KW - Mountain glacier

KW - Sea surface temperature

KW - Southern hemisphere

KW - Southern westerly winds

UR - https://www.scopus.com/pages/publications/85195311766

U2 - 10.1016/j.epsl.2024.118802

DO - 10.1016/j.epsl.2024.118802

M3 - Article

AN - SCOPUS:85195311766

SN - 0012-821X

VL - 641

JO - Earth and Planetary Science Letters

JF - Earth and Planetary Science Letters

M1 - 118802

ER -

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

Abstract

UN SDGs

Keywords

Access to Document

Other files and links

SAEF: Securing Antarctica’s Environmental Future – An Evidence-Based, Informatics Approach

Cite this

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

Abstract

UN SDGs

Keywords

Access to Document

Other files and links

Projects

SAEF: Securing Antarctica’s Environmental Future – An Evidence-Based, Informatics Approach

Cite this