Deglacial history of the West Antarctic Ice Sheet in the Weddell Sea embayment: Constraints on past ice volume change

Abstract

The retreat history of the West Antarctic Ice Sheet (WAIS) since the Last Glacial Maximum
\nis important for understanding the process of rapid deglaciation, constraining models
\nthat seek to predict the future trajectory of the ice sheet, and for estimating rates of sea-level
\nchange. Here we report new glacial geologic data from the southwestern Weddell Sea embayment
\nthat demonstrate that this part of the WAIS was thinner than previously suggested, and
\nthat there was progressive thinning of the ice sheet by 230–480 m since ca. 15 ka. We use geomorphological
\ndata and a numerical ice sheet model to reconstruct the ice sheet in the Weddell
\nSea at the Last Glacial Maximum. The volume of this ice would have added between 1.4 and
\n2.0 m to postglacial sea-level rise and would not have been suffi cient to contribute signifi cantly
\nto meltwater pulse 1A, a rapid rise in sea level ~14,200 yr ago.