Scientists have discovered a giant canyon buried under ice.
Ice has blanketed Greenland for millions of years. In some places it can be almost two miles thick. Scientists now know that hidden beneath the ice is a canyon that extends hundreds of miles north from near the center of the ice sheet. By combining more than four years’ worth of ice-penetrating radar measurements from NASA’s Operation IceBridge mission with other data sets, researchers created a topographic map of Greenland’s bedrock. The map shed light on the existence of a canyon that measures at least 460 miles in length and a half-mile deep. At greater than 1.5 times the length of the Grand Canyon, it is longer than any known canyon on Earth. Watch the visualization for a tour of Greenland’s massive, under-ice canyon. In the visualization the terrain elevation is shown using color, where greens indicate areas above sea level, browns indicate areas below sea level, and yellows indicate areas at or near sea level.