Geophysical Research Letters, 36, L08502; doi:10.1029/2009GL037524.
Non‐annular atmospheric circulation change induced by stratospheric ozone depletion and its role in the recent increase of Antarctic sea ice extent
John Turner (British Antarctic Survey, National Environment Research Council, Cambridge, U.K.), Josefino C. Comiso (NASA Goddard Space Flight Center, Greenbelt, MD, U.S.A.), Gareth J. Marshall, Tom A. Lachlan‐Cope, Tom Bracegirdle, Ted Maksym, Michael P. Meredith, Zhaomin Wang, and Andrew Orr (British Antarctic Survey, National Environment Research Council, Cambridge, U.K.)
Abstract
Based on a new analysis of passive microwave satellite data, we demonstrate that the annual mean extent of Antarctic sea ice has increased at a statistically significant rate of 0.97% dec−1 since the late 1970s. The largest increase has been in autumn when there has been a dipole of significant positive and negative trends in the Ross and Amundsen‐Bellingshausen Seas respectively. The autumn increase in the Ross Sea sector is primarily a result of stronger cyclonic atmospheric flow over the Amundsen Sea. Model experiments suggest that the trend towards stronger cyclonic circulation is mainly a result of stratospheric ozone depletion, which has strengthened autumn wind speeds around the continent, deepening the Amundsen Sea Low through flow separation around the high coastal orography. However, statistics derived from a climate model control run suggest that the observed sea ice increase might still be within the range of natural climate variability.
(Received 29 January 2009, accepted 25 March 2009, published 23 April 2009.)
(2009), Non‐annular atmospheric circulation change induced by stratospheric ozone depletion and its role in the recent increase of Antarctic sea ice extent, Geophysical Research Letters, 36, L08502; doi:10.1029/2009GL037524.
Link to abstract: http://www.agu.org/pubs/crossref/2009/2009GL037524.shtml
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