Model Studies of the Effects of Global Warming and Antarctic Sea Ice Changes on Antarctic and Global Climates

• Main Authors: Simmonds, Ian, Budd, W. F.
• Other Authors: MELBOURNE UNIV PARKVILLE (AUSTRALIA)
• Format: Text
• Language: English
• Published: 1992
• Subjects: Meteorology; Snow; Ice and Permafrost; *SEA ICE; *ENVIRONMENTAL IMPACT; *ANTARCTIC REGIONS; CIRCULATION; CLIMATE; GLOBAL; ICE; MODELS; OCEANS; REDUCTION; SOUTHERN HEMISPHERE; TEMPERATURE; VARIATIONS; WIND; GREENHOUSE EFFECT; *Global climate change; Component Reports; *Global warming; Antarctic; Fairbanks; Antarc*; Ice; permafrost; Sea ice; Alaska
• Online Access: http://www.dtic.mil/docs/citations/ADP007296; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADP007296

We discuss the results obtained in three experiments by changing the global ocean temperatures and the concentration and distribution of Antarctic sea ice in a General Circulation Model of July climate, with a view to determining the local and global impacts of Antarctic sea ice variations alone, as distinct with those coupled with global scale temperature changes which may be associated with global warming. In all cases there were significant changes in the upward flux of sensible heat over the sea ice zone associated with the reductions of sea ice. The response of weaker westerlies between 40 and 65 deg S was common to all three experiments. Our analyses suggest that a significant proportion of this is a response to the change in sea ice concentration alone. (Not surprisingly, further north of this region most of the changes induced in the wind structure in the global forcing experiment can be seen as due unambiguously to the differential changes in ocean temperatures.). This weakening of the westerlies means there is less mechanical forcing of the ocean in this region. From this we suggest that when consideration is given to the possible impact of feedbacks not considered in these experiments, sea ice changes alone, and particularly those in the Southern Hemisphere, have the potential to induce changes on a hemispheric scale. This article is from 'Proceedings of the International Conference on the Role of the Polar Regions in Global Change Held in Fairbanks, Alaska on 11-15 June 1990. Volume 1', AD-A253 027, p256-262. See also Volume 2, AD-A253 028.