Assessment of surface winds over the Atlantic, Indian, and Pacific Ocean sectors of the Southern Ocean in CMIP5 models: historical bias, forcing response, and state dependence
An assessment of the fifth Coupled Models Intercomparison Project (CMIP5) models' simulation of the near-surface westerly wind jet position and strength over the Atlantic, Indian and Pacific sectors of the Southern Ocean is presented. Compared with reanalysis climatologies there is an equatorwa...
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Online Access: | http://nora.nerc.ac.uk/id/eprint/502096/ https://nora.nerc.ac.uk/id/eprint/502096/1/jgrd50153.pdf https://doi.org/10.1002/jgrd.50153 |
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ftnerc:oai:nora.nerc.ac.uk:502096 2023-05-15T18:25:12+02:00 Assessment of surface winds over the Atlantic, Indian, and Pacific Ocean sectors of the Southern Ocean in CMIP5 models: historical bias, forcing response, and state dependence Bracegirdle, Thomas J. Shuckburgh, Emily Sallee, Jean-Baptiste Wang, Zhaomin Meijers, Andrew J.S. Bruneau, Nicolas Phillips, Tony Wilcox, Laura J. 2013-01-30 text http://nora.nerc.ac.uk/id/eprint/502096/ https://nora.nerc.ac.uk/id/eprint/502096/1/jgrd50153.pdf https://doi.org/10.1002/jgrd.50153 en eng Wiley https://nora.nerc.ac.uk/id/eprint/502096/1/jgrd50153.pdf Bracegirdle, Thomas J. orcid:0000-0002-8868-4739 Shuckburgh, Emily orcid:0000-0001-9206-3444 Sallee, Jean-Baptiste; Wang, Zhaomin; Meijers, Andrew J.S. orcid:0000-0003-3876-7736 Bruneau, Nicolas; Phillips, Tony orcid:0000-0002-3058-9157 Wilcox, Laura J. 2013 Assessment of surface winds over the Atlantic, Indian, and Pacific Ocean sectors of the Southern Ocean in CMIP5 models: historical bias, forcing response, and state dependence. Journal of Geophysical Research: Atmospheres, 118 (2). 547-562. https://doi.org/10.1002/jgrd.50153 <https://doi.org/10.1002/jgrd.50153> Chemistry Publication - Article PeerReviewed 2013 ftnerc https://doi.org/10.1002/jgrd.50153 2023-02-04T19:37:04Z An assessment of the fifth Coupled Models Intercomparison Project (CMIP5) models' simulation of the near-surface westerly wind jet position and strength over the Atlantic, Indian and Pacific sectors of the Southern Ocean is presented. Compared with reanalysis climatologies there is an equatorward bias of 3.3° (inter-model standard deviation of ± 1.9°) in the ensemble mean position of the zonal mean jet. The ensemble mean strength is biased slightly too weak, with the largest biases over the Pacific sector (−1.4 ± 1.2 m/s, −19%). An analysis of atmosphere-only (AMIP) experiments indicates that 28% of the zonal mean position bias comes from coupling of the ocean/ice models to the atmosphere. The response to future emissions scenarios (RCP4.5 and RCP8.5) is characterized by two phases: (i) the period of most rapid ozone recovery (2000–2049) during which there is insignificant change in summer; and (ii) the period 2050–2098 during which RCP4.5 simulations show no significant change but RCP8.5 simulations show poleward shifts (0.33, 0.18 and 0.27°/decade over the Atlantic, Indian and Pacific sectors, respectively), and increases in strength (0.07, 0.08 and 0.15 m/s/decade, respectively). The models with larger equatorward position biases generally show larger poleward shifts (i.e. state dependence). This inter-model relationship is strongest over the Pacific sector (r = −0.91) and weakest over the Atlantic sector (r = −0.39). An assessment of jet structure shows that over the Atlantic sector jet shift is not clearly linked to indices of jet structure whereas over the Pacific sector the distance between the sub-polar and sub-tropical westerly jets appears to be important. Article in Journal/Newspaper Southern Ocean Natural Environment Research Council: NERC Open Research Archive Southern Ocean Pacific Indian Journal of Geophysical Research: Atmospheres 118 2 547 562 |
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Open Polar |
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Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
topic |
Chemistry |
spellingShingle |
Chemistry Bracegirdle, Thomas J. Shuckburgh, Emily Sallee, Jean-Baptiste Wang, Zhaomin Meijers, Andrew J.S. Bruneau, Nicolas Phillips, Tony Wilcox, Laura J. Assessment of surface winds over the Atlantic, Indian, and Pacific Ocean sectors of the Southern Ocean in CMIP5 models: historical bias, forcing response, and state dependence |
topic_facet |
Chemistry |
description |
An assessment of the fifth Coupled Models Intercomparison Project (CMIP5) models' simulation of the near-surface westerly wind jet position and strength over the Atlantic, Indian and Pacific sectors of the Southern Ocean is presented. Compared with reanalysis climatologies there is an equatorward bias of 3.3° (inter-model standard deviation of ± 1.9°) in the ensemble mean position of the zonal mean jet. The ensemble mean strength is biased slightly too weak, with the largest biases over the Pacific sector (−1.4 ± 1.2 m/s, −19%). An analysis of atmosphere-only (AMIP) experiments indicates that 28% of the zonal mean position bias comes from coupling of the ocean/ice models to the atmosphere. The response to future emissions scenarios (RCP4.5 and RCP8.5) is characterized by two phases: (i) the period of most rapid ozone recovery (2000–2049) during which there is insignificant change in summer; and (ii) the period 2050–2098 during which RCP4.5 simulations show no significant change but RCP8.5 simulations show poleward shifts (0.33, 0.18 and 0.27°/decade over the Atlantic, Indian and Pacific sectors, respectively), and increases in strength (0.07, 0.08 and 0.15 m/s/decade, respectively). The models with larger equatorward position biases generally show larger poleward shifts (i.e. state dependence). This inter-model relationship is strongest over the Pacific sector (r = −0.91) and weakest over the Atlantic sector (r = −0.39). An assessment of jet structure shows that over the Atlantic sector jet shift is not clearly linked to indices of jet structure whereas over the Pacific sector the distance between the sub-polar and sub-tropical westerly jets appears to be important. |
format |
Article in Journal/Newspaper |
author |
Bracegirdle, Thomas J. Shuckburgh, Emily Sallee, Jean-Baptiste Wang, Zhaomin Meijers, Andrew J.S. Bruneau, Nicolas Phillips, Tony Wilcox, Laura J. |
author_facet |
Bracegirdle, Thomas J. Shuckburgh, Emily Sallee, Jean-Baptiste Wang, Zhaomin Meijers, Andrew J.S. Bruneau, Nicolas Phillips, Tony Wilcox, Laura J. |
author_sort |
Bracegirdle, Thomas J. |
title |
Assessment of surface winds over the Atlantic, Indian, and Pacific Ocean sectors of the Southern Ocean in CMIP5 models: historical bias, forcing response, and state dependence |
title_short |
Assessment of surface winds over the Atlantic, Indian, and Pacific Ocean sectors of the Southern Ocean in CMIP5 models: historical bias, forcing response, and state dependence |
title_full |
Assessment of surface winds over the Atlantic, Indian, and Pacific Ocean sectors of the Southern Ocean in CMIP5 models: historical bias, forcing response, and state dependence |
title_fullStr |
Assessment of surface winds over the Atlantic, Indian, and Pacific Ocean sectors of the Southern Ocean in CMIP5 models: historical bias, forcing response, and state dependence |
title_full_unstemmed |
Assessment of surface winds over the Atlantic, Indian, and Pacific Ocean sectors of the Southern Ocean in CMIP5 models: historical bias, forcing response, and state dependence |
title_sort |
assessment of surface winds over the atlantic, indian, and pacific ocean sectors of the southern ocean in cmip5 models: historical bias, forcing response, and state dependence |
publisher |
Wiley |
publishDate |
2013 |
url |
http://nora.nerc.ac.uk/id/eprint/502096/ https://nora.nerc.ac.uk/id/eprint/502096/1/jgrd50153.pdf https://doi.org/10.1002/jgrd.50153 |
geographic |
Southern Ocean Pacific Indian |
geographic_facet |
Southern Ocean Pacific Indian |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_relation |
https://nora.nerc.ac.uk/id/eprint/502096/1/jgrd50153.pdf Bracegirdle, Thomas J. orcid:0000-0002-8868-4739 Shuckburgh, Emily orcid:0000-0001-9206-3444 Sallee, Jean-Baptiste; Wang, Zhaomin; Meijers, Andrew J.S. orcid:0000-0003-3876-7736 Bruneau, Nicolas; Phillips, Tony orcid:0000-0002-3058-9157 Wilcox, Laura J. 2013 Assessment of surface winds over the Atlantic, Indian, and Pacific Ocean sectors of the Southern Ocean in CMIP5 models: historical bias, forcing response, and state dependence. Journal of Geophysical Research: Atmospheres, 118 (2). 547-562. https://doi.org/10.1002/jgrd.50153 <https://doi.org/10.1002/jgrd.50153> |
op_doi |
https://doi.org/10.1002/jgrd.50153 |
container_title |
Journal of Geophysical Research: Atmospheres |
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118 |
container_issue |
2 |
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547 |
op_container_end_page |
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1766206471749500928 |