| Summary: | This paper is an attempt to extract an average picture of the response of the Southern Annular Mode (SAM) to increasing greenhouse gases (GHG) forcing from a multimodel ensemble of simulations conducted in the framework of the IPCC 4th assessment experiments. Our analysis confirms that the climate change signal in the mid-to high southern latitudes projects strongly into the positive phase (PP) of the SAM. Over the present climate time slice (1970-1999), multimodel ensemble mean reproduce the regional warming around the Antarctic Peninsula (AP) associated with the SAM. When increasing GHG (future time slice, 2070-2099), warming in the neighborhoods of the AP and decreasing sea-ice volume in the sea-ice edge region in the Amundsen and Weddell Seas intensifies, suggesting that recent observed sea-ice trends around AP could be associated to anthropogenic forcings. Changes in surface temperature and sea-ice are consistent with anomalous atmospheric heat transport associated with circulation anomalies. Copyright 2005 by the American Geophysical Union.
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