Share this article Share this article COLUMBIA, Md., Dec. 17, 2020 /PRNewswire/ -- Scientists at Universities Space Research Association and their colleagues at NASA, University of Texas and other organizations have determined that the slope of the bedrock underneath glaciers around the Greenland ice sheet can either spread ice thinning farther inland or stall it. Outlet glaciers are essentially rivers of ice flowing over the bedrock and draining into the ocean. They retreat and thin as the climate warms and this thinning spreads farther inland toward the center of the ice sheet. Recently, by investigating the bed topography of 141 outlet glaciers around Greenland, scientists gained a better understanding of which glaciers could have a significant impact on the Greenland Ice Sheet's contribution to sea level rise in the coming decades. They found that steep bedrock features, called "knickpoints", can effectively stall the spread of ice thinning. This often occurs in regions where the bed topography is mountainous. In contrast, in regions with more gentle topography where knickpoints are not present or are less steep, glaciers can transmit ice thinning far into the interior, away from the seacoasts. The results were published in