%0 Journal Article
%T Mechanisms causing reduced Arctic sea ice loss in a coupled climate model
%A A. E. West
%A A. B. Keen
%A H. T. Hewitt
%J The Cryosphere Discussions
%D 2012
%I Copernicus Publications
%R 10.5194/tcd-6-2653-2012
%X The fully-coupled climate model HadGEM1 produces one of the most accurate simulations of the historical record of Arctic sea ice seen in the IPCC AR4 multi-model ensemble. In this study, we examine projections of sea ice decline out to 2030, produced by two ensembles of HadGEM1 with natural and anthropogenic forcings included. These ensembles project a significant slowing of the rate of ice loss to occur after 2010, with some integrations even simulating a small increase in ice area. We use an energy budget of the Arctic to examine the causes of this slowdown. A negative feedback effect by which rapid reductions in ice thickness north of Greenland reduce ice export is found to play a major role. A slight reduction in ocean-to-ice heat flux in the relevant period, caused by changes in the MOC and subpolar gyre in some integrations, is also found to play a part. Finally, we assess the likelihood of a slowdown occurring in the real world due to these causes.
%U http://www.the-cryosphere-discuss.net/6/2653/2012/tcd-6-2653-2012.pdf