Greenland’s ice sheet is melting in more ways than we thought
The front of 79 North Glacier (Janin Schaffer, Alfred-Wegener-Ins/)The Greenland ice sheet—a 656,000-square-mile mass of ice covering most of its namesake’s land mass—is melting at a rapid pace. Ice loss has ramped up by seven times since the 1990s, and rising air temperatures due to climate change are largely to blame.But for the tongues of ice that extend off glaciers and into the sea, what’s happening below is also important. A new study in Nature Geoscience found that a previously unknown seafloor landscape is bringing warm water to the 79º North glacier, located in the northeastern part of the country, and eroding a 50-mile-long lobe of ice hanging off the glacier. And that could have serious repercussions for the entire ice sheet. “What was known is that these ice tongues melt from underneath,” says Wilken-Jon von Appen, oceanographer at the Alfred Wegener Institute, coauthor of the study. “What was not...