Insights into spatial sensitivities of ice mass response to environmental change from the SeaRISE ice sheet modeling project I: Antarctica

摘要

[1] Atmospheric, oceanic, and subglacial forcing scenarios from the Sea-level Response toIce Sheet Evolution (SeaRISE) project are applied to six three-dimensionalthermomechanical ice-sheet models to assess Antarctic ice sheet sensitivity over a 500 yeartimescale and to inform future modeling and field studies. Results indicate (i) growth withwarming, except within low-latitude basins (where inland thickening is outpaced bymarginal thinning); (ii) mass loss with enhanced sliding (with basins dominated by highdriving 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 thesignal due to its marine setting and extensive ice shelves; cf. minimal impact in the TerreAdelie, George V, Oates, and Victoria Land region of East Antarctica). Ice loss due todynamic changes associated with enhanced sliding and/or sub-shelf melting exceeds thegain due to increased precipitation. Furthermore, differences in results between and withinbasins as well as the controlling impact of sub-shelf melting on ice dynamics highlight theneed for improved understanding of basal conditions, grounding-zone processes, ocean-iceinteractions, and the numerical representation of all three.