Younger Dryas ice margin retreat in Greenland: new evidence from southwestern Greenland

Abstract. To date the final stage in deglaciation of Greenland shelf, when a contiguous ice sheet margin on inner shelf transitioned to outlet glaciers troughs with intervening ice-free areas, we generated cosmogenic 10Be dates from bedrock knobs six outlying islands along stretch 300 km southwestern coast. Despite inheritance influencing some dates, ages generally support Ice Sheet (GrIS) that retreated off during middle Younger Dryas (YD) period. Published 10Be- and 14C-dated records show this history GrIS is seen other parts but large variations extent speed retreat, sometimes even between neighbouring areas. Areas chronology extending into Allerød period no marked change at Allerød–YD transition except northernmost Greenland. In contrast, landforms (moraines grounding zone wedges) have been suggested indicate YD readvances or long-lasting stillstands shelf. However, these features dated primarily by correlation cold periods core temperature records. retreat late explained advection warm subsurface water increased seasonality. Our results therefore point complexity climate–ice relation urgent need for direct dating early