MODELLING THE IMPACT OF SEA ICE AND LAND ICE ON EURASIAN CLIMATE

The new ice sheet reconstructions by the QUEEN group make substantial changes to previous estimates used by the Palaeoclimate Model Intercomparison project (PMIP) for their simulations of the Last Glacial Maximum (LGM). Similarly there are considerable uncertainties about the extent of North Atlantic sea ice and the magnitude of sea surface temperature (SST) cooling. These uncertainties are potentially strongly linked since changes in sea ice and SST will substantially impact on the accumulation over the ice sheets. We present a series of climate model simulations which contrast the role of SST, sea ice, and ice sheet in determining the climate over Europe. We find that changes in SST and sea ice can substantially alter the storm tracks and hence the precipitation over the Fennoscandinavian ice sheet. Changes in the height of the ice sheet cause only modest change in climate much beyond the immediate vicinity of the ice.