The modern and glacial overturning circulation in the Atlantic ocean in PMIP coupled model simulations
This study analyses the response of the Atlantic meridional overturning circulation (AMOC) to LGM forcings and boundary conditions in nine PMIP coupled model simulations, including both GCMs and Earth system Models of Intermediate Complexity. Model results differ widely. The AMOC slows down consider...
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2007
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ftsouthampton:oai:eprints.soton.ac.uk:349156 2023-07-30T03:57:56+02:00 The modern and glacial overturning circulation in the Atlantic ocean in PMIP coupled model simulations Weber, S.L. Drijfhout, S.S. Abe-Ouchi, A. Crucifix, M. Eby, M. Ganopolski, A. Murakami, S. Otto-Bliesner, B. Peltier, W.R. 2007 https://eprints.soton.ac.uk/349156/ unknown Weber, S.L., Drijfhout, S.S., Abe-Ouchi, A., Crucifix, M., Eby, M., Ganopolski, A., Murakami, S., Otto-Bliesner, B. and Peltier, W.R. (2007) The modern and glacial overturning circulation in the Atlantic ocean in PMIP coupled model simulations. Climate of the Past, 3 (1), 51-64. (doi:10.5194/cp-3-51-2007 <http://dx.doi.org/10.5194/cp-3-51-2007>). Article PeerReviewed 2007 ftsouthampton https://doi.org/10.5194/cp-3-51-2007 2023-07-09T21:44:43Z This study analyses the response of the Atlantic meridional overturning circulation (AMOC) to LGM forcings and boundary conditions in nine PMIP coupled model simulations, including both GCMs and Earth system Models of Intermediate Complexity. Model results differ widely. The AMOC slows down considerably (by 20–40%) during the LGM as compared to the modern climate in four models, there is a slight reduction in one model and four models show a substantial increase in AMOC strength (by 10–40%). It is found that a major controlling factor for the AMOC response is the density contrast between Antarctic Bottom Water (AABW) and North Atlantic Deep Water (NADW) at their source regions. Changes in the density contrast are determined by the opposing effects of changes in temperature and salinity, with more saline AABW as compared to NADW consistently found in all models and less cooling of AABW in all models but one. In only two models is the AMOC response during the LGM directly related to the response in net evaporation over the Atlantic basin. Most models show large changes in the ocean freshwater transports into the basin, but this does not seem to affect the AMOC response. Finally, there is some dependence on the accuracy of the control state. Article in Journal/Newspaper Antarc* Antarctic NADW North Atlantic Deep Water North Atlantic University of Southampton: e-Prints Soton Antarctic Climate of the Past 3 1 51 64 |
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University of Southampton: e-Prints Soton |
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ftsouthampton |
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unknown |
description |
This study analyses the response of the Atlantic meridional overturning circulation (AMOC) to LGM forcings and boundary conditions in nine PMIP coupled model simulations, including both GCMs and Earth system Models of Intermediate Complexity. Model results differ widely. The AMOC slows down considerably (by 20–40%) during the LGM as compared to the modern climate in four models, there is a slight reduction in one model and four models show a substantial increase in AMOC strength (by 10–40%). It is found that a major controlling factor for the AMOC response is the density contrast between Antarctic Bottom Water (AABW) and North Atlantic Deep Water (NADW) at their source regions. Changes in the density contrast are determined by the opposing effects of changes in temperature and salinity, with more saline AABW as compared to NADW consistently found in all models and less cooling of AABW in all models but one. In only two models is the AMOC response during the LGM directly related to the response in net evaporation over the Atlantic basin. Most models show large changes in the ocean freshwater transports into the basin, but this does not seem to affect the AMOC response. Finally, there is some dependence on the accuracy of the control state. |
format |
Article in Journal/Newspaper |
author |
Weber, S.L. Drijfhout, S.S. Abe-Ouchi, A. Crucifix, M. Eby, M. Ganopolski, A. Murakami, S. Otto-Bliesner, B. Peltier, W.R. |
spellingShingle |
Weber, S.L. Drijfhout, S.S. Abe-Ouchi, A. Crucifix, M. Eby, M. Ganopolski, A. Murakami, S. Otto-Bliesner, B. Peltier, W.R. The modern and glacial overturning circulation in the Atlantic ocean in PMIP coupled model simulations |
author_facet |
Weber, S.L. Drijfhout, S.S. Abe-Ouchi, A. Crucifix, M. Eby, M. Ganopolski, A. Murakami, S. Otto-Bliesner, B. Peltier, W.R. |
author_sort |
Weber, S.L. |
title |
The modern and glacial overturning circulation in the Atlantic ocean in PMIP coupled model simulations |
title_short |
The modern and glacial overturning circulation in the Atlantic ocean in PMIP coupled model simulations |
title_full |
The modern and glacial overturning circulation in the Atlantic ocean in PMIP coupled model simulations |
title_fullStr |
The modern and glacial overturning circulation in the Atlantic ocean in PMIP coupled model simulations |
title_full_unstemmed |
The modern and glacial overturning circulation in the Atlantic ocean in PMIP coupled model simulations |
title_sort |
modern and glacial overturning circulation in the atlantic ocean in pmip coupled model simulations |
publishDate |
2007 |
url |
https://eprints.soton.ac.uk/349156/ |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic NADW North Atlantic Deep Water North Atlantic |
genre_facet |
Antarc* Antarctic NADW North Atlantic Deep Water North Atlantic |
op_relation |
Weber, S.L., Drijfhout, S.S., Abe-Ouchi, A., Crucifix, M., Eby, M., Ganopolski, A., Murakami, S., Otto-Bliesner, B. and Peltier, W.R. (2007) The modern and glacial overturning circulation in the Atlantic ocean in PMIP coupled model simulations. Climate of the Past, 3 (1), 51-64. (doi:10.5194/cp-3-51-2007 <http://dx.doi.org/10.5194/cp-3-51-2007>). |
op_doi |
https://doi.org/10.5194/cp-3-51-2007 |
container_title |
Climate of the Past |
container_volume |
3 |
container_issue |
1 |
container_start_page |
51 |
op_container_end_page |
64 |
_version_ |
1772820315502542848 |