Exploring AMOC Regime Change over the Past Four Decades through Ocean Reanalyses
We examine North Atlantic climate variability using an ensemble of ocean reanalysis datasets to study the Atlantic Meridional Overturning Circulation (AMOC) from 1979 to 2018. The dataset intercomparison shows good agreement for the latest period (1995–2018) for AMOC dynamics, characterized by a wea...
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Online Access: | https://www.openaccessrepository.it/record/142217 https://doi.org/10.3390/cli10040059 |
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ftopenaccessrep:oai:zenodo.org:142217 2023-10-29T02:37:43+01:00 Exploring AMOC Regime Change over the Past Four Decades through Ocean Reanalyses Vincenzo de Toma Vincenzo Artale Chunxue Yang 2022-04-08 https://www.openaccessrepository.it/record/142217 https://doi.org/10.3390/cli10040059 eng eng url:https://www.openaccessrepository.it/communities/itmirror https://www.openaccessrepository.it/record/142217 doi:10.3390/cli10040059 info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by/4.0/ Atmospheric Science info:eu-repo/semantics/article publication-article 2022 ftopenaccessrep https://doi.org/10.3390/cli10040059 2023-10-03T22:21:00Z We examine North Atlantic climate variability using an ensemble of ocean reanalysis datasets to study the Atlantic Meridional Overturning Circulation (AMOC) from 1979 to 2018. The dataset intercomparison shows good agreement for the latest period (1995–2018) for AMOC dynamics, characterized by a weaker overturning circulation after 1995 and a more intense one during 1979–1995, with varying intensity across the various datasets. The correlation between leading empirical orthogonal functions suggests that the AMOC weakening has connections with cooler (warmer) sea surface temperature (SST) and lower (higher) ocean heat content in the subpolar (subtropical) gyre in the North Atlantic. Barotropic stream function and Gulf Stream index reveal a shrinking subpolar gyre and an expanding subtropical gyre during the strong-AMOC period and vice versa, consistently with Labrador Sea deep convection reduction. We also observed an east–west salt redistribution between the two periods. Additional analyses show that the AMOC variability is related to the North Atlantic Oscillation phase change around 1995. One of the datasets included in the comparison shows an overestimation of AMOC variability, notwithstanding the model SST bias reduction via ERA-Interim flux adjustments: further studies with a set of numerical experiments will help explain this behavior. Article in Journal/Newspaper Labrador Sea North Atlantic North Atlantic oscillation Istituto Nazionale di Fisica Nucleare (INFN): Open Access Repository Climate 10 4 59 |
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Open Polar |
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Istituto Nazionale di Fisica Nucleare (INFN): Open Access Repository |
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ftopenaccessrep |
language |
English |
topic |
Atmospheric Science |
spellingShingle |
Atmospheric Science Vincenzo de Toma Vincenzo Artale Chunxue Yang Exploring AMOC Regime Change over the Past Four Decades through Ocean Reanalyses |
topic_facet |
Atmospheric Science |
description |
We examine North Atlantic climate variability using an ensemble of ocean reanalysis datasets to study the Atlantic Meridional Overturning Circulation (AMOC) from 1979 to 2018. The dataset intercomparison shows good agreement for the latest period (1995–2018) for AMOC dynamics, characterized by a weaker overturning circulation after 1995 and a more intense one during 1979–1995, with varying intensity across the various datasets. The correlation between leading empirical orthogonal functions suggests that the AMOC weakening has connections with cooler (warmer) sea surface temperature (SST) and lower (higher) ocean heat content in the subpolar (subtropical) gyre in the North Atlantic. Barotropic stream function and Gulf Stream index reveal a shrinking subpolar gyre and an expanding subtropical gyre during the strong-AMOC period and vice versa, consistently with Labrador Sea deep convection reduction. We also observed an east–west salt redistribution between the two periods. Additional analyses show that the AMOC variability is related to the North Atlantic Oscillation phase change around 1995. One of the datasets included in the comparison shows an overestimation of AMOC variability, notwithstanding the model SST bias reduction via ERA-Interim flux adjustments: further studies with a set of numerical experiments will help explain this behavior. |
format |
Article in Journal/Newspaper |
author |
Vincenzo de Toma Vincenzo Artale Chunxue Yang |
author_facet |
Vincenzo de Toma Vincenzo Artale Chunxue Yang |
author_sort |
Vincenzo de Toma |
title |
Exploring AMOC Regime Change over the Past Four Decades through Ocean Reanalyses |
title_short |
Exploring AMOC Regime Change over the Past Four Decades through Ocean Reanalyses |
title_full |
Exploring AMOC Regime Change over the Past Four Decades through Ocean Reanalyses |
title_fullStr |
Exploring AMOC Regime Change over the Past Four Decades through Ocean Reanalyses |
title_full_unstemmed |
Exploring AMOC Regime Change over the Past Four Decades through Ocean Reanalyses |
title_sort |
exploring amoc regime change over the past four decades through ocean reanalyses |
publishDate |
2022 |
url |
https://www.openaccessrepository.it/record/142217 https://doi.org/10.3390/cli10040059 |
genre |
Labrador Sea North Atlantic North Atlantic oscillation |
genre_facet |
Labrador Sea North Atlantic North Atlantic oscillation |
op_relation |
url:https://www.openaccessrepository.it/communities/itmirror https://www.openaccessrepository.it/record/142217 doi:10.3390/cli10040059 |
op_rights |
info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.3390/cli10040059 |
container_title |
Climate |
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10 |
container_issue |
4 |
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59 |
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1781062766015021056 |