OSO0910

To date, understanding of ice sheet retreat within Pine Island Bay (PIB) following the Last Glacial Maximum (LGM) was based on seven radiocarbon dates and scattered sea-floor geomorphic evidence. During austral summer 2009-2010, restricted sea ice cover allowed for the collection of 27 sediment cores from the critical central trough region and a dense grid of multibeam swath bathymetry data. This research was carried out as a collaborative effort between Swedish and US scientists using the Swedish icebreaker Oden. Combining the cores collected on this cruise with data from prior cruises, we conducted a detailed analysis of the retreat of the expanded portion of the West Antarctic Ice Sheet that drained into PIB. This retreat history is bolstered by 23 new radiocarbon dates from sediments deposited in the wake of the retreating ice sheet.