Map showing rates of grounding-line migration and their coincidence with ocean conditions around Antarctica between 2010 and 2016. (Credit: Hannes Konrad et al, University of Leeds.) Antarctica’s ocean-front glaciers are retreating, according a new satellite survey that raises additional concerns about the massive continent’s potential contribution to rising sea levels. Antarctica, which contains enough ice to raise the oceans by about 200 feet, is a continent of ice that flows outward to the ocean at numerous large glaciers. These mostly submerged glaciers rest deep on the seafloor at a point called the “grounding line,” where ocean, ice and bedrock meet. But at 10.7 percent of these glaciers, the ice masses are moving at a significant speed back toward the center of the continent as they melt from below, often because of the incursion of warm ocean water, which causes the grounding line to retreat. Only about 1.9 percent of […]