A new estimate using sheet modeling finds that Greenland's rate of ice loss this century could outpace that of any century over the past 12,000 years, when the last Ice Age ended. The team used an ice sheet model to simulate changes to the southwestern sector of the Greenland Ice Sheet, starting from the beginning of the Holocene epoch 12,000 years ago and extending forward 80 years to 2100. "Moraines are large piles of debris that you can find on the landscape that mark the former edge of an ice sheet or glacier. This gave us confidence that the ice sheet model was performing well and giving us meaningful results. Though the project focused on southwestern Greenland, research shows that changes in the rates of ice loss there tend to correspond tightly with changes across the entire ice sheet.