Rare Glacial River Drains Potentially Harmful Lakes

Scientists working in Antarctica had previously shown that surface lakes can destabilize the floating ice shelves that surround the continent and cause them to break-up. However, such effects of these lakes on Greenland’s floating ice, often called “tongues” instead of ice shelves, have not drawn similar attention. This is despite the fact that Greenland is melting more quickly than Antarctica. To study Petermann glacier, Alison Banwell, a glaciologist at the University of Colorado Boulder, and her colleagues at the University of Chicago turned to observations of surface lakes and rivers collected by the Landsat 8 satellite from 2014 to 2016. The team focused on the glacier’s floating terminus in Petermann Fjord.