Insignificant change in Antarctic snowmelt volume since 1979

Abstract

Surface snowmelt is widespread in coastal Antarctica. Satellite-based microwave sensors have been observing melt area and duration for over three decades. However, these observations do not reveal the total volume of meltwater produced on the ice sheet. Here we present an Antarctic melt volume climatology for the period 1979–2010, obtained using a regional climate model equipped with realistic snow physics. We find that mean continent-wide meltwater volume (1979–2010) amounts to 89 Gt y 1 with large interannual variability (s = 41 Gt y 1). Of this amount, 57 Gt y 1 (64%) is produced on the floating ice shelves extending from the grounded ice sheet, and 71 Gt y 1 in West-Antarctica, including the Antarctic Peninsula. We find no statistically significant trend in either continentwide or regional meltwater volume for the 31-year period 1979–2010.