The Cryosphere Discussions www.the-cryosphere-discuss.net 1994-0432 1994-0440 2 5 2008 10.5194/tcd-2-759-2008 http://www.the-cryosphere-discuss.net/2/759/2008/ http://www.the-cryosphere-discuss.net/2/759/2008/tcd-2-759-2008.html http://www.the-cryosphere-discuss.net/2/759/2008/tcd-2-759-2008.pdf 759 776 2008-10-28 Model resolution influence on simulated sea ice decline J. O. Sewall jos@vt.edu Department of Geosciences, Virginia Tech, Blacksburg, VA, USA Satellite observations and model predictions of recent and future Arctic sea ice decline have raised concerns over the timing and potential impacts of a seasonally ice-free Arctic Ocean. Model predictions of seasonally ice-free Arctic conditions are, however, highly variable. Here I present results from fourteen climate system models from the World Climate Research Programme's (WCRP's) Coupled Model Intercomparison Project phase 3 (CMIP3) multi-model dataset that indicate modeled Arctic sea ice sensitivity to increased atmospheric CO₂ forcing is strongly correlated with ice/ocean model horizontal resolution. Based on coupled model analyses and ice only simulations with the Los Alamos National Lab sea ice model (CICE), the correlation between declining Arctic sea ice cover and ice/ocean model resolution appears to depend largely on ocean model resolution and its influence on ocean heat transport into the Arctic basin. The correlation between model resolution, northward ocean heat transport, and the degree of Arctic ice loss is independent of ice model physics and complexity. 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