From the air, the western edge of Greenland's ice sheet looks like an aging elephant's skin--gray and cracked, as melting at the margins exposes dirt accumulated over tens of thousands of years. A few kilometers inland, however, the gray gives way to blazing white that goes on for hundreds of miles. These vast glaciers contain snow that has fallen and compacted over millennia. The ice sheet--roughly four times the size of California, and more than three kilometers thick in places--is, in essence, a vast frozen reservoir of fresh water.

About 300 kilometers from the coast, high above the Arctic Circle, is the newest polar science station in Greenland, comprising two tents, a hut, two sledge-mounted domes, and a few vehicles. The only way to describe the location is by GPS coördinates: 77º26'54.92885" N, 51º3'19.89396" W. The station sits atop 2,500 meters of ice.