Published: Sep 1, 2013 by The PISM Authors
Antarctic climate scenarios and forcing experiments from the 31 member Sea-level Response to Ice Sheet Evolution (SeaRISE) project are applied to six three-dimensional thermomechanical ice-sheet models, including a PISM model lead by M. Martin at PIK. This paper assesses the century-scale model sensitivity revealed by these experiments. Results indicate (i) growth with warming, except within low-latitude basins (where inland thickening is outpaced by marginal thinning); (ii) mass loss with enhanced sliding (with basins dominated by high driving stresses affected more than basins with low-surface-slope streaming ice); and (iii) mass loss with enhanced ice shelf melting (with changes in West Antarctica dominating the signal due to its marine setting and extensive ice shelves). Ice loss due to dynamic changes associated with enhanced sliding and/or sub-shelf melting exceeds the gain due to increased precipitation. Remaining uncertainties include differences between basins and the impact of sub-shelf melting on ice dynamics.