The effect of windstress change on future sea level change in the Southern Ocean

• Published in: Geophysical research letters Vol. 39; no. 23
• Main Authors: Bouttes, N., Gregory, J. M., Kuhlbrodt, T., Suzuki, T.
• Format: Journal Article
• Language: English
• Published: Washington, DC Blackwell Publishing Ltd 16.12.2012; American Geophysical Union; John Wiley & Sons, Inc
• Subjects: CMIP5; Earth Sciences; Earth, ocean, space; Exact sciences and technology; Geophysics; Indian; Marine; Mathematical models; Ocean, Atmosphere; Oceanography; Oceans; Phases; Physical oceanography; Sciences of the Universe; Sea level; Sea level changes; Sea level rise; Southern Ocean; Spreads; Strengthening; windstress; Antarctic Ocean; Arctic Ocean; Pacific Ocean; Asia; India; North Pacific; Multimodel; projects; Westerly wind; General circulation models; Regional scope; Climate models; global; digital simulation; Ocean-atmosphere model; Dipole; Polar region; Comparative study; sea level
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/2012GL054207

AOGCMs of the two latest phases (CMIP3 and CMIP5) of the Coupled Model Intercomparison Project, like earlier AOGCMs, predict large regional variations in future sea level change. The model‐mean pattern of change in CMIP3 and CMIP5 is very similar, and its most prominent feature is a zonal dipole in the Southern Ocean: sea level rise is larger than the global mean north of 50°S and smaller than the global mean south of 50°S in most models. The individual models show widely varying patterns, although the inter‐model spread in local sea level change is smaller in CMIP5 than in CMIP3. Here we investigate whether changes in windstress can explain the different patterns of projected sea level change, especially the Southern Ocean feature, using two AOGCMs forced by the changes in windstress from the CMIP3 and CMIP5 AOGCMs. We show that the strengthening and poleward shift of westerly windstress accounts for the most of the large spread among models in magnitude of this feature. In the Indian, North Pacific and Arctic Oceans, the windstress change is influential, but does not completely account for the projected sea level change. Key Points The model mean pattern of sea level change is very similar in CMIP3 and CMIP5 The sea level spread in the Southern Ocean is mainly due to windstress change Windstress change is influential in some other regions but not the only factor