On the stability of the Atlantic meridional overturning circulation during the last deglaciation
Using a generalized stability indicator L, we explore the stability of the Atlantic meridional overturning circulation (AMOC) during the last deglaciation based on a paleoclimate simulation. From the last glacial maximum, as forced by various external climate forcings, notably the meltwater forcing,...
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climate dynamics
2015
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Online Access: | https://hdl.handle.net/20.500.11897/206108 https://doi.org/10.1007/s00382-014-2153-1 |
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ftpekinguniv:oai:localhost:20.500.11897/206108 2023-05-15T15:44:17+02:00 On the stability of the Atlantic meridional overturning circulation during the last deglaciation Liu, Wei Liu, Zhengyu Cheng, Jun Hu, Haibo Liu, W (reprint author), Univ Calif San Diego, Scripps Inst Oceanog, CASPO, La Jolla, CA 92093 USA. N Carolina State Univ, Cooperat Inst Climate & Satellites, Raleigh, NC 27695 USA. NOAA, Natl Climat Data Ctr, Asheville, NC USA. Univ Calif San Diego, Scripps Inst Oceanog, CASPO, La Jolla, CA 92093 USA. Peking Univ, Lab Climate Ocean & Atmosphere Studies, Beijing 100871, Peoples R China. Univ Wisconsin, Ctr Climat Res, Madison, WI USA. Nanjing Univ Informat Sci & Technol, Sch Marine Sci, Minist Educ, Key Lab Meteorol Disaster, Nanjing, Jiangsu, Peoples R China. Nanjing Univ, Sch Atmospher Sci, Nanjing 210008, Jiangsu, Peoples R China. 2015 https://hdl.handle.net/20.500.11897/206108 https://doi.org/10.1007/s00382-014-2153-1 en eng climate dynamics CLIMATE DYNAMICS.2015,44,(5-6),1257-1275. 748132 0930-7575 http://hdl.handle.net/20.500.11897/206108 1432-0894 doi:10.1007/s00382-014-2153-1 WOS:000350364500006 SCI AMOC Stability indicator Freshwater transport Feedback The last deglaciation OCEAN-ATMOSPHERE MODEL MULTIPLE EQUILIBRIA REGIME AIR-SEA INTERACTIONS PAST 20,000 YEARS THERMOHALINE CIRCULATION GLACIAL MAXIMUM SOUTH-ATLANTIC CENTRAL GREENLAND CLIMATE CHANGES BERING STRAIT Journal 2015 ftpekinguniv https://doi.org/20.500.11897/206108 https://doi.org/10.1007/s00382-014-2153-1 2021-08-01T08:30:06Z Using a generalized stability indicator L, we explore the stability of the Atlantic meridional overturning circulation (AMOC) during the last deglaciation based on a paleoclimate simulation. From the last glacial maximum, as forced by various external climate forcings, notably the meltwater forcing, the AMOC experiences a collapse and a subsequent rapid recovery in the early stage of deglaciation. This change of the AMOC induces an anomalous freshwater divergence and later convergence across the Atlantic and therefore leads to a positive L, suggesting a negative basin-scale salinity advection feedback and, in turn, a mono-stable deglacial AMOC. Further analyses show that most anomalous freshwater is induced by the AMOC via the southern boundary of the Atlantic at 34 degrees S where the freshwater transport (M-ovS) is about equally controlled by the upper branch of the AMOC and the upper ocean salinity along 34 degrees S. From 19 to 17 ka, as a result of multiple climate feedbacks associated with the AMOC change, the upper ocean at 34 degrees S is largely salinified, which helps to induce a switch in M-ovS, from import to export. Our study has important implications to the deglacial simulations by climate models. A decomposition of L shows that the AMOC stability is mostly determined by two terms, the salinity stratification at 34 degrees S and the change of stratification with the AMOC. Both terms appear positive in model. However, the former is likely to be distorted towards positive, as associated with a common bias existing over the South Atlantic in climate models. Therefore, the AMOC is potentially biased towards mono-stability in most paleoclimate simulations. Meteorology & Atmospheric Sciences SCI(E) 2 ARTICLE wliu5wisc@gmail.com 5-6 1257-1275 44 Journal/Newspaper Bering Strait Greenland Peking University Institutional Repository (PKU IR) Bering Strait Greenland Climate Dynamics 44 5-6 1257 1275 |
institution |
Open Polar |
collection |
Peking University Institutional Repository (PKU IR) |
op_collection_id |
ftpekinguniv |
language |
English |
topic |
AMOC Stability indicator Freshwater transport Feedback The last deglaciation OCEAN-ATMOSPHERE MODEL MULTIPLE EQUILIBRIA REGIME AIR-SEA INTERACTIONS PAST 20,000 YEARS THERMOHALINE CIRCULATION GLACIAL MAXIMUM SOUTH-ATLANTIC CENTRAL GREENLAND CLIMATE CHANGES BERING STRAIT |
spellingShingle |
AMOC Stability indicator Freshwater transport Feedback The last deglaciation OCEAN-ATMOSPHERE MODEL MULTIPLE EQUILIBRIA REGIME AIR-SEA INTERACTIONS PAST 20,000 YEARS THERMOHALINE CIRCULATION GLACIAL MAXIMUM SOUTH-ATLANTIC CENTRAL GREENLAND CLIMATE CHANGES BERING STRAIT Liu, Wei Liu, Zhengyu Cheng, Jun Hu, Haibo On the stability of the Atlantic meridional overturning circulation during the last deglaciation |
topic_facet |
AMOC Stability indicator Freshwater transport Feedback The last deglaciation OCEAN-ATMOSPHERE MODEL MULTIPLE EQUILIBRIA REGIME AIR-SEA INTERACTIONS PAST 20,000 YEARS THERMOHALINE CIRCULATION GLACIAL MAXIMUM SOUTH-ATLANTIC CENTRAL GREENLAND CLIMATE CHANGES BERING STRAIT |
description |
Using a generalized stability indicator L, we explore the stability of the Atlantic meridional overturning circulation (AMOC) during the last deglaciation based on a paleoclimate simulation. From the last glacial maximum, as forced by various external climate forcings, notably the meltwater forcing, the AMOC experiences a collapse and a subsequent rapid recovery in the early stage of deglaciation. This change of the AMOC induces an anomalous freshwater divergence and later convergence across the Atlantic and therefore leads to a positive L, suggesting a negative basin-scale salinity advection feedback and, in turn, a mono-stable deglacial AMOC. Further analyses show that most anomalous freshwater is induced by the AMOC via the southern boundary of the Atlantic at 34 degrees S where the freshwater transport (M-ovS) is about equally controlled by the upper branch of the AMOC and the upper ocean salinity along 34 degrees S. From 19 to 17 ka, as a result of multiple climate feedbacks associated with the AMOC change, the upper ocean at 34 degrees S is largely salinified, which helps to induce a switch in M-ovS, from import to export. Our study has important implications to the deglacial simulations by climate models. A decomposition of L shows that the AMOC stability is mostly determined by two terms, the salinity stratification at 34 degrees S and the change of stratification with the AMOC. Both terms appear positive in model. However, the former is likely to be distorted towards positive, as associated with a common bias existing over the South Atlantic in climate models. Therefore, the AMOC is potentially biased towards mono-stability in most paleoclimate simulations. Meteorology & Atmospheric Sciences SCI(E) 2 ARTICLE wliu5wisc@gmail.com 5-6 1257-1275 44 |
author2 |
Liu, W (reprint author), Univ Calif San Diego, Scripps Inst Oceanog, CASPO, La Jolla, CA 92093 USA. N Carolina State Univ, Cooperat Inst Climate & Satellites, Raleigh, NC 27695 USA. NOAA, Natl Climat Data Ctr, Asheville, NC USA. Univ Calif San Diego, Scripps Inst Oceanog, CASPO, La Jolla, CA 92093 USA. Peking Univ, Lab Climate Ocean & Atmosphere Studies, Beijing 100871, Peoples R China. Univ Wisconsin, Ctr Climat Res, Madison, WI USA. Nanjing Univ Informat Sci & Technol, Sch Marine Sci, Minist Educ, Key Lab Meteorol Disaster, Nanjing, Jiangsu, Peoples R China. Nanjing Univ, Sch Atmospher Sci, Nanjing 210008, Jiangsu, Peoples R China. |
format |
Journal/Newspaper |
author |
Liu, Wei Liu, Zhengyu Cheng, Jun Hu, Haibo |
author_facet |
Liu, Wei Liu, Zhengyu Cheng, Jun Hu, Haibo |
author_sort |
Liu, Wei |
title |
On the stability of the Atlantic meridional overturning circulation during the last deglaciation |
title_short |
On the stability of the Atlantic meridional overturning circulation during the last deglaciation |
title_full |
On the stability of the Atlantic meridional overturning circulation during the last deglaciation |
title_fullStr |
On the stability of the Atlantic meridional overturning circulation during the last deglaciation |
title_full_unstemmed |
On the stability of the Atlantic meridional overturning circulation during the last deglaciation |
title_sort |
on the stability of the atlantic meridional overturning circulation during the last deglaciation |
publisher |
climate dynamics |
publishDate |
2015 |
url |
https://hdl.handle.net/20.500.11897/206108 https://doi.org/10.1007/s00382-014-2153-1 |
geographic |
Bering Strait Greenland |
geographic_facet |
Bering Strait Greenland |
genre |
Bering Strait Greenland |
genre_facet |
Bering Strait Greenland |
op_source |
SCI |
op_relation |
CLIMATE DYNAMICS.2015,44,(5-6),1257-1275. 748132 0930-7575 http://hdl.handle.net/20.500.11897/206108 1432-0894 doi:10.1007/s00382-014-2153-1 WOS:000350364500006 |
op_doi |
https://doi.org/20.500.11897/206108 https://doi.org/10.1007/s00382-014-2153-1 |
container_title |
Climate Dynamics |
container_volume |
44 |
container_issue |
5-6 |
container_start_page |
1257 |
op_container_end_page |
1275 |
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1766378575568568320 |