Role of CO2 and Southern Ocean winds in glacial abrupt climate change
The study of Greenland ice cores revealed two decades ago the abrupt character of glacial millennial-scale climate variability. Several triggering mechanisms have been proposed and confronted against growing proxy-data evidence. Although the implication of North Atlantic deep water (NADW) formation...
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ftcsic:oai:digital.csic.es:10261/61185 2024-02-11T10:04:19+01:00 Role of CO2 and Southern Ocean winds in glacial abrupt climate change Banderas, Rubén Álvarez-Solas, J. Montoya, Marisa 2012-06-01 http://hdl.handle.net/10261/61185 https://doi.org/10.5194/cp-8-1011-2012 en eng Copernicus Publications Publisher’s version BANDERAS, R., ÁLVAREZ-SOLAS, J., MONTOYA, M. (2012). Role of CO2 and Southern Ocean winds in glacial abrupt climate change. Climate of the Past, 8, 1011-1021. 10.5194/cp-8-1011-2012 http://hdl.handle.net/10261/61185 doi:10.5194/cp-8-1011-2012 open Climate change Winds CO2 artículo http://purl.org/coar/resource_type/c_6501 2012 ftcsic https://doi.org/10.5194/cp-8-1011-2012 2024-01-16T09:42:52Z The study of Greenland ice cores revealed two decades ago the abrupt character of glacial millennial-scale climate variability. Several triggering mechanisms have been proposed and confronted against growing proxy-data evidence. Although the implication of North Atlantic deep water (NADW) formation reorganisations in glacial abrupt climate change seems robust nowadays, the final cause of these reorganisations remains unclear. Here, the role of CO2 and Southern Ocean winds is investigated using a coupled model of intermediate complexity in an experimental setup designed such that the climate system resides close to a threshold found in previous studies. An initial abrupt surface air temperature (SAT) increase over the North Atlantic by 4K in less than a decade, followed by a more gradual warming greater than 10K on centennial timescales, is simulated in response to increasing atmospheric CO2 levels and/or enhancing southern westerlies. The simulated peak warming shows a similar pattern and amplitude over Greenland as registered in ice core records of Dansgaard-Oeschger (D/O) events. This is accompanied by a strong Atlantic meridional overturning circulation (AMOC) intensification. The AMOC strengthening is found to be caused by a northward shift of NADW formation sites into the Nordic Seas as a result of a northward retreat of the sea-ice front in response to higher temperatures. This leads to enhanced heat loss to the atmosphere as well as reduced freshwater fluxes via reduced seaice import into the region. In this way, a new mechanism that is consistent with proxy data is identified by which abrupt climate change can be promoted Peer reviewed Article in Journal/Newspaper Greenland Greenland ice cores ice core NADW Nordic Seas North Atlantic Deep Water North Atlantic Sea ice Southern Ocean Digital.CSIC (Spanish National Research Council) Greenland Southern Ocean Climate of the Past 8 3 1011 1021 |
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Open Polar |
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Digital.CSIC (Spanish National Research Council) |
op_collection_id |
ftcsic |
language |
English |
topic |
Climate change Winds CO2 |
spellingShingle |
Climate change Winds CO2 Banderas, Rubén Álvarez-Solas, J. Montoya, Marisa Role of CO2 and Southern Ocean winds in glacial abrupt climate change |
topic_facet |
Climate change Winds CO2 |
description |
The study of Greenland ice cores revealed two decades ago the abrupt character of glacial millennial-scale climate variability. Several triggering mechanisms have been proposed and confronted against growing proxy-data evidence. Although the implication of North Atlantic deep water (NADW) formation reorganisations in glacial abrupt climate change seems robust nowadays, the final cause of these reorganisations remains unclear. Here, the role of CO2 and Southern Ocean winds is investigated using a coupled model of intermediate complexity in an experimental setup designed such that the climate system resides close to a threshold found in previous studies. An initial abrupt surface air temperature (SAT) increase over the North Atlantic by 4K in less than a decade, followed by a more gradual warming greater than 10K on centennial timescales, is simulated in response to increasing atmospheric CO2 levels and/or enhancing southern westerlies. The simulated peak warming shows a similar pattern and amplitude over Greenland as registered in ice core records of Dansgaard-Oeschger (D/O) events. This is accompanied by a strong Atlantic meridional overturning circulation (AMOC) intensification. The AMOC strengthening is found to be caused by a northward shift of NADW formation sites into the Nordic Seas as a result of a northward retreat of the sea-ice front in response to higher temperatures. This leads to enhanced heat loss to the atmosphere as well as reduced freshwater fluxes via reduced seaice import into the region. In this way, a new mechanism that is consistent with proxy data is identified by which abrupt climate change can be promoted Peer reviewed |
format |
Article in Journal/Newspaper |
author |
Banderas, Rubén Álvarez-Solas, J. Montoya, Marisa |
author_facet |
Banderas, Rubén Álvarez-Solas, J. Montoya, Marisa |
author_sort |
Banderas, Rubén |
title |
Role of CO2 and Southern Ocean winds in glacial abrupt climate change |
title_short |
Role of CO2 and Southern Ocean winds in glacial abrupt climate change |
title_full |
Role of CO2 and Southern Ocean winds in glacial abrupt climate change |
title_fullStr |
Role of CO2 and Southern Ocean winds in glacial abrupt climate change |
title_full_unstemmed |
Role of CO2 and Southern Ocean winds in glacial abrupt climate change |
title_sort |
role of co2 and southern ocean winds in glacial abrupt climate change |
publisher |
Copernicus Publications |
publishDate |
2012 |
url |
http://hdl.handle.net/10261/61185 https://doi.org/10.5194/cp-8-1011-2012 |
geographic |
Greenland Southern Ocean |
geographic_facet |
Greenland Southern Ocean |
genre |
Greenland Greenland ice cores ice core NADW Nordic Seas North Atlantic Deep Water North Atlantic Sea ice Southern Ocean |
genre_facet |
Greenland Greenland ice cores ice core NADW Nordic Seas North Atlantic Deep Water North Atlantic Sea ice Southern Ocean |
op_relation |
Publisher’s version BANDERAS, R., ÁLVAREZ-SOLAS, J., MONTOYA, M. (2012). Role of CO2 and Southern Ocean winds in glacial abrupt climate change. Climate of the Past, 8, 1011-1021. 10.5194/cp-8-1011-2012 http://hdl.handle.net/10261/61185 doi:10.5194/cp-8-1011-2012 |
op_rights |
open |
op_doi |
https://doi.org/10.5194/cp-8-1011-2012 |
container_title |
Climate of the Past |
container_volume |
8 |
container_issue |
3 |
container_start_page |
1011 |
op_container_end_page |
1021 |
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1790600891322073088 |