Changes to Indian Ocean subantarctic mode water in a coupled climate model as CO2 forcing increases
Subantarctic mode water (SAMW) has been shown to be a good indicator of anthropogenic climate change in coupled climate models. SAMW in a coupled climate model and the response of modeled SAMW to increasing CO2 are examined in detail. How SAMW adjusts from climatological values toward a new equilibr...
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ftunivreading:oai:centaur.reading.ac.uk:19456 2024-06-23T07:47:27+00:00 Changes to Indian Ocean subantarctic mode water in a coupled climate model as CO2 forcing increases Banks, H. T. Wood, R. A. Gregory, Jonathan M. 2002 https://centaur.reading.ac.uk/19456/ unknown American Meteorological Society Banks, H. T., Wood, R. A. and Gregory, J. M. <https://centaur.reading.ac.uk/view/creators/90000874.html> orcid:0000-0003-1296-8644 (2002) Changes to Indian Ocean subantarctic mode water in a coupled climate model as CO2 forcing increases. Journal of Physical Oceanography, 32 (10). pp. 2816-2827. ISSN 0022-3670 doi: https://doi.org/10.1175/1520-0485(2002)032<2816:CTIOSM>2.0.CO;2 <https://doi.org/10.1175/1520-0485(2002)032<2816:CTIOSM>2.0.CO;2> Article PeerReviewed 2002 ftunivreading https://doi.org/10.1175/1520-0485(2002)032<2816:CTIOSM>2.0.CO;2 2024-06-11T14:54:05Z Subantarctic mode water (SAMW) has been shown to be a good indicator of anthropogenic climate change in coupled climate models. SAMW in a coupled climate model and the response of modeled SAMW to increasing CO2 are examined in detail. How SAMW adjusts from climatological values toward a new equilibrium in the coupled model, with different climatological temperature and salinity properties, is shown. The combined formation rate of SAMW and Antarctic intermediate water is calculated as approximately 18 Sv (Sv ≡ 106 m3 s−1) in the Indian sector of the Southern Ocean, slightly lower than climatological values would suggest. When forced with increasing CO2, SAMW is produced at a similar rate but at lower densities. This result suggests that the rate of heat uptake in this part of the ocean will be unchanged by anthropogenic forcing. The important signal in the response of SAMW is the shift to colder and fresher values on isopycnals that is believed to be related to changes in thermodynamic surface forcing. It is shown that, given uniform forcing, SAMW is expected to enhance the signal relative to other water masses. Independent increases in surface heating or freshwater forcing can produce changes similar to those observed, but the two different types of forcing are distinguishable using separate forcing experiments, hodographs, and passive anomaly tracers. The changes in SAMW forced by increasing CO2 are dominated by surface heating, but changes to freshwater fluxes are also important. Article in Journal/Newspaper Antarc* Antarctic Southern Ocean CentAUR: Central Archive at the University of Reading Antarctic Indian Southern Ocean |
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CentAUR: Central Archive at the University of Reading |
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ftunivreading |
language |
unknown |
description |
Subantarctic mode water (SAMW) has been shown to be a good indicator of anthropogenic climate change in coupled climate models. SAMW in a coupled climate model and the response of modeled SAMW to increasing CO2 are examined in detail. How SAMW adjusts from climatological values toward a new equilibrium in the coupled model, with different climatological temperature and salinity properties, is shown. The combined formation rate of SAMW and Antarctic intermediate water is calculated as approximately 18 Sv (Sv ≡ 106 m3 s−1) in the Indian sector of the Southern Ocean, slightly lower than climatological values would suggest. When forced with increasing CO2, SAMW is produced at a similar rate but at lower densities. This result suggests that the rate of heat uptake in this part of the ocean will be unchanged by anthropogenic forcing. The important signal in the response of SAMW is the shift to colder and fresher values on isopycnals that is believed to be related to changes in thermodynamic surface forcing. It is shown that, given uniform forcing, SAMW is expected to enhance the signal relative to other water masses. Independent increases in surface heating or freshwater forcing can produce changes similar to those observed, but the two different types of forcing are distinguishable using separate forcing experiments, hodographs, and passive anomaly tracers. The changes in SAMW forced by increasing CO2 are dominated by surface heating, but changes to freshwater fluxes are also important. |
format |
Article in Journal/Newspaper |
author |
Banks, H. T. Wood, R. A. Gregory, Jonathan M. |
spellingShingle |
Banks, H. T. Wood, R. A. Gregory, Jonathan M. Changes to Indian Ocean subantarctic mode water in a coupled climate model as CO2 forcing increases |
author_facet |
Banks, H. T. Wood, R. A. Gregory, Jonathan M. |
author_sort |
Banks, H. T. |
title |
Changes to Indian Ocean subantarctic mode water in a coupled climate model as CO2 forcing increases |
title_short |
Changes to Indian Ocean subantarctic mode water in a coupled climate model as CO2 forcing increases |
title_full |
Changes to Indian Ocean subantarctic mode water in a coupled climate model as CO2 forcing increases |
title_fullStr |
Changes to Indian Ocean subantarctic mode water in a coupled climate model as CO2 forcing increases |
title_full_unstemmed |
Changes to Indian Ocean subantarctic mode water in a coupled climate model as CO2 forcing increases |
title_sort |
changes to indian ocean subantarctic mode water in a coupled climate model as co2 forcing increases |
publisher |
American Meteorological Society |
publishDate |
2002 |
url |
https://centaur.reading.ac.uk/19456/ |
geographic |
Antarctic Indian Southern Ocean |
geographic_facet |
Antarctic Indian Southern Ocean |
genre |
Antarc* Antarctic Southern Ocean |
genre_facet |
Antarc* Antarctic Southern Ocean |
op_relation |
Banks, H. T., Wood, R. A. and Gregory, J. M. <https://centaur.reading.ac.uk/view/creators/90000874.html> orcid:0000-0003-1296-8644 (2002) Changes to Indian Ocean subantarctic mode water in a coupled climate model as CO2 forcing increases. Journal of Physical Oceanography, 32 (10). pp. 2816-2827. ISSN 0022-3670 doi: https://doi.org/10.1175/1520-0485(2002)032<2816:CTIOSM>2.0.CO;2 <https://doi.org/10.1175/1520-0485(2002)032<2816:CTIOSM>2.0.CO;2> |
op_doi |
https://doi.org/10.1175/1520-0485(2002)032<2816:CTIOSM>2.0.CO;2 |
_version_ |
1802651546828144640 |