Non-monotonic feedback dependence under abrupt CO2 forcing due to a North Atlantic pattern effect
Effective climate sensitivity (EffCS), commonly estimated from model simulations with abrupt 4xCO(2) for 150 years, has been shown to depend on the CO2 forcing level. To understand this dependency systematically, we performed a series of simulations with a range of abrupt CO2 forcing in two climate...
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ftncar:oai:drupal-site.org:articles_26502 2023-10-01T03:57:45+02:00 Non-monotonic feedback dependence under abrupt CO2 forcing due to a North Atlantic pattern effect Mitevski, Ivan (author) Dong, Yue (author) Polvani, Lorenzo M. (author) Rugenstein, Maria (author) Orbe, Clara (author) 2023-07-28 https://doi.org/10.1029/2023GL103617 en eng Geophysical Research Letters--Geophysical Research Letters--0094-8276--1944-8007 articles:26502 doi:10.1029/2023GL103617 ark:/85065/d7rn3cwv Copyright author(s). This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. article Text 2023 ftncar https://doi.org/10.1029/2023GL103617 2023-09-04T18:18:44Z Effective climate sensitivity (EffCS), commonly estimated from model simulations with abrupt 4xCO(2) for 150 years, has been shown to depend on the CO2 forcing level. To understand this dependency systematically, we performed a series of simulations with a range of abrupt CO2 forcing in two climate models. Our results indicate that normalized EffCS values in these simulations are a non-monotonic function of the CO2 forcing, decreasing between 3x and 4xCO(2) in CESM1-LE (2x and 3xCO(2) in GISS-E2.1-G) and increasing at higher CO2 levels. The minimum EffCS value, caused by anomalously negative radiative feedbacks, arises mainly from sea-surface temperature (SST) relative cooling in the tropical and subtropical North Atlantic. This cooling is associated with the formation of the North Atlantic Warming Hole and Atlantic Meridional Overturning Circulation collapse under CO2 forcing. Our findings imply that understanding changes in North Atlantic SST patterns is important for constraining near-future and equilibrium global warming. Article in Journal/Newspaper North Atlantic OpenSky (NCAR/UCAR - National Center for Atmospheric Research/University Corporation for Atmospheric Research) Geophysical Research Letters 50 14 |
institution |
Open Polar |
collection |
OpenSky (NCAR/UCAR - National Center for Atmospheric Research/University Corporation for Atmospheric Research) |
op_collection_id |
ftncar |
language |
English |
description |
Effective climate sensitivity (EffCS), commonly estimated from model simulations with abrupt 4xCO(2) for 150 years, has been shown to depend on the CO2 forcing level. To understand this dependency systematically, we performed a series of simulations with a range of abrupt CO2 forcing in two climate models. Our results indicate that normalized EffCS values in these simulations are a non-monotonic function of the CO2 forcing, decreasing between 3x and 4xCO(2) in CESM1-LE (2x and 3xCO(2) in GISS-E2.1-G) and increasing at higher CO2 levels. The minimum EffCS value, caused by anomalously negative radiative feedbacks, arises mainly from sea-surface temperature (SST) relative cooling in the tropical and subtropical North Atlantic. This cooling is associated with the formation of the North Atlantic Warming Hole and Atlantic Meridional Overturning Circulation collapse under CO2 forcing. Our findings imply that understanding changes in North Atlantic SST patterns is important for constraining near-future and equilibrium global warming. |
author2 |
Mitevski, Ivan (author) Dong, Yue (author) Polvani, Lorenzo M. (author) Rugenstein, Maria (author) Orbe, Clara (author) |
format |
Article in Journal/Newspaper |
title |
Non-monotonic feedback dependence under abrupt CO2 forcing due to a North Atlantic pattern effect |
spellingShingle |
Non-monotonic feedback dependence under abrupt CO2 forcing due to a North Atlantic pattern effect |
title_short |
Non-monotonic feedback dependence under abrupt CO2 forcing due to a North Atlantic pattern effect |
title_full |
Non-monotonic feedback dependence under abrupt CO2 forcing due to a North Atlantic pattern effect |
title_fullStr |
Non-monotonic feedback dependence under abrupt CO2 forcing due to a North Atlantic pattern effect |
title_full_unstemmed |
Non-monotonic feedback dependence under abrupt CO2 forcing due to a North Atlantic pattern effect |
title_sort |
non-monotonic feedback dependence under abrupt co2 forcing due to a north atlantic pattern effect |
publishDate |
2023 |
url |
https://doi.org/10.1029/2023GL103617 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_relation |
Geophysical Research Letters--Geophysical Research Letters--0094-8276--1944-8007 articles:26502 doi:10.1029/2023GL103617 ark:/85065/d7rn3cwv |
op_rights |
Copyright author(s). This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. |
op_doi |
https://doi.org/10.1029/2023GL103617 |
container_title |
Geophysical Research Letters |
container_volume |
50 |
container_issue |
14 |
_version_ |
1778529754555613184 |