Southern Ocean buoyancy forcing of ocean ventilation and glacial atmospheric CO2
Published Atmospheric CO2 concentrations over glacial-interglacial cycles closely correspond to Antarctic temperature patterns. These are distinct from temperature variations in the mid to northern latitudes, so this suggests that the Southern Ocean is pivotal in controlling natural CO2 concentratio...
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ftunivexeter:oai:ore.exeter.ac.uk:10871/20008 2024-09-15T17:47:39+00:00 Southern Ocean buoyancy forcing of ocean ventilation and glacial atmospheric CO2 Watson, Andrew J. Vallis, Geoffrey K. Nikurashin, Maxim 2015 http://hdl.handle.net/10871/20008 https://doi.org/10.1038/ngeo2538 en eng Nature Publishing Group http://www.nature.com/ngeo/journal/v8/n11/full/ngeo2538.html Nature Geoscience, 2015, Vol. 8, pp. 861 - 864 doi:10.1038/ngeo2538 http://hdl.handle.net/10871/20008 1752-0894 Nature Geoscience Copyright © 2015, Rights Managed by Nature Publishing Group 2016-03-28 Publisher's policy Article 2015 ftunivexeter https://doi.org/10.1038/ngeo2538 2024-07-29T03:24:15Z Published Atmospheric CO2 concentrations over glacial-interglacial cycles closely correspond to Antarctic temperature patterns. These are distinct from temperature variations in the mid to northern latitudes, so this suggests that the Southern Ocean is pivotal in controlling natural CO2 concentrations. Here we assess the sensitivity of atmospheric CO2 concentrations to glacial-interglacial changes in the ocean's meridional overturning circulation using a circulation model for upwelling and eddy transport in the Southern Ocean coupled with a simple biogeochemical description. Under glacial conditions, a broader region of surface buoyancy loss results in upwelling farther to the north, relative to interglacials. The northern location of upwelling results in reduced CO2 outgassing and stronger carbon sequestration in the deep ocean: we calculate that the shift to this glacial-style circulation can draw down 30 to 60ppm of atmospheric CO2. We therefore suggest that the direct effect of temperatures on Southern Ocean buoyancy forcing, and hence the residual overturning circulation, explains much of the strong correlation between Antarctic temperature variations and atmospheric CO2 concentrations over glacial-interglacial cycles. Article in Journal/Newspaper Antarc* Antarctic Southern Ocean University of Exeter: Open Research Exeter (ORE) Nature Geoscience 8 11 861 864 |
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University of Exeter: Open Research Exeter (ORE) |
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English |
description |
Published Atmospheric CO2 concentrations over glacial-interglacial cycles closely correspond to Antarctic temperature patterns. These are distinct from temperature variations in the mid to northern latitudes, so this suggests that the Southern Ocean is pivotal in controlling natural CO2 concentrations. Here we assess the sensitivity of atmospheric CO2 concentrations to glacial-interglacial changes in the ocean's meridional overturning circulation using a circulation model for upwelling and eddy transport in the Southern Ocean coupled with a simple biogeochemical description. Under glacial conditions, a broader region of surface buoyancy loss results in upwelling farther to the north, relative to interglacials. The northern location of upwelling results in reduced CO2 outgassing and stronger carbon sequestration in the deep ocean: we calculate that the shift to this glacial-style circulation can draw down 30 to 60ppm of atmospheric CO2. We therefore suggest that the direct effect of temperatures on Southern Ocean buoyancy forcing, and hence the residual overturning circulation, explains much of the strong correlation between Antarctic temperature variations and atmospheric CO2 concentrations over glacial-interglacial cycles. |
format |
Article in Journal/Newspaper |
author |
Watson, Andrew J. Vallis, Geoffrey K. Nikurashin, Maxim |
spellingShingle |
Watson, Andrew J. Vallis, Geoffrey K. Nikurashin, Maxim Southern Ocean buoyancy forcing of ocean ventilation and glacial atmospheric CO2 |
author_facet |
Watson, Andrew J. Vallis, Geoffrey K. Nikurashin, Maxim |
author_sort |
Watson, Andrew J. |
title |
Southern Ocean buoyancy forcing of ocean ventilation and glacial atmospheric CO2 |
title_short |
Southern Ocean buoyancy forcing of ocean ventilation and glacial atmospheric CO2 |
title_full |
Southern Ocean buoyancy forcing of ocean ventilation and glacial atmospheric CO2 |
title_fullStr |
Southern Ocean buoyancy forcing of ocean ventilation and glacial atmospheric CO2 |
title_full_unstemmed |
Southern Ocean buoyancy forcing of ocean ventilation and glacial atmospheric CO2 |
title_sort |
southern ocean buoyancy forcing of ocean ventilation and glacial atmospheric co2 |
publisher |
Nature Publishing Group |
publishDate |
2015 |
url |
http://hdl.handle.net/10871/20008 https://doi.org/10.1038/ngeo2538 |
genre |
Antarc* Antarctic Southern Ocean |
genre_facet |
Antarc* Antarctic Southern Ocean |
op_relation |
http://www.nature.com/ngeo/journal/v8/n11/full/ngeo2538.html Nature Geoscience, 2015, Vol. 8, pp. 861 - 864 doi:10.1038/ngeo2538 http://hdl.handle.net/10871/20008 1752-0894 Nature Geoscience |
op_rights |
Copyright © 2015, Rights Managed by Nature Publishing Group 2016-03-28 Publisher's policy |
op_doi |
https://doi.org/10.1038/ngeo2538 |
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Nature Geoscience |
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8 |
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11 |
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861 |
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864 |
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1810497116687040512 |