The Cryosphere Discussions www.the-cryosphere-discuss.net 1994-0432 1994-0440 3 3 2009 10.5194/tcd-3-729-2009 http://www.the-cryosphere-discuss.net/3/729/2009/ http://www.the-cryosphere-discuss.net/3/729/2009/tcd-3-729-2009.html http://www.the-cryosphere-discuss.net/3/729/2009/tcd-3-729-2009.pdf 729 764 2009-09-11 An efficient regional energy-moisture balance model for simulation of the Greenland ice sheet response to climate change A. Robinson robinson@pik-potsdam.de R. Calov A. Ganopolski Potsdam Institute for Climate Impact Research, Potsdam, Germany University of Potsdam, Potsdam, Germany In order to explore the response of the Greenland ice sheet (GIS) to climate change on long (centennial to multi-millennial) time scales, a regional energy-moisture balance model has been developed. This model simulates seasonal variations of temperature and precipitation over Greenland and explicitly accounts for elevation and albedo feedbacks. These fields are used to force a high resolution ice sheet model through the annual mean surface temperature and mass balance. The melt component of the mass balance is computed here using both a conventional positive degree day approach and a more physically-based alternative. As a validation of the model, we first simulated temperature and precipitation over Greenland for the prescribed, present-day topography of Greenland and compared them with empirical data. For the present-day climate, simulated surface boundary conditions for the GIS do not differ significantly from those of a simple parameterization used in many previous simulations. However, for a prescribed, ice-free state, the differences in simulated climatology and surface mass balance between the regional energy-moisture balance model and the conventional approach become significant, with our model showing much stronger summer warming. 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