Sensitivity experiments with a numerical ice sheet model including full thermo-mechanical coupling
An efficient numerical ice sheet model, including time dependence and full thermo-mechanical coupling, has been developed to investigate the thermal regime and overall configuration of apolar ice sheet with respect to changing environmental conditions. From basic sensitivity experiments, in which a schematic East-Antarctic Ice Sheet is forced with a typicalglacial-interglacial climatic shift, it is found that (i):the mutual interaction of temperature and deformation has a stabilizing effect on its steady state configuration and (ii) in the transientmode, this climatic transition initially leads to increased ice thickness due to enhanced accumulation, whereafter this trend is reversed due to a warmer base. Time scales for this reversal areof the order of 10 3 years in marginal zones and of 10 4 years in interior parts. Time-dependent modelling of the Vostok flowline, indicates that the Vostok Station area has risen about 95m since the beginning of the present interglacial due to thermo-mechanical effects, which is of particular interest in interpreting the palaeoclimatic signal of the obtained ice core there.