The landscape could be in upstate New York, western Maine, or any number of other scenic places: a few large lakes, many small ones, wide rivers and slow-flowing streams, water-filled hollows and soggy ground, all set in a stony land. But that’s where the resemblance to familiar landscapes ends. Here, no clouds float by, no rain falls, and no stars shine; there is no sunlight or moonshine, and no air at all. Instead, spread over this water-rich landscape, covering it almost completely and sealing it in, is 5 million square miles of glacial ice, roughly two miles thick and a million years old.
This bizarre scene is found in Antarctica, the coldest place on Earth. If it were possible to lift up the giant ice sheets, that watery, stony terrain is what would remain. But of course it is not possible, so nobody knows what the buried landscape really looks like or how many living things may be down there. As of only a few decades ago, no one knew this world of buried lakes and rivers even existed. Now scientists are paying serious attention to it. Journalists have dubbed it “the last unexplored place on Earth” and “one of Earth’s last frontiers.” A veteran Russian glaciologist went so far as to call the discovery of one of Antarctica’s greatest subglacial lakes, Lake Vostok (now known to be the sixth-largest lake in the world, with a volume of about 1,300 cubic miles), “among the most important geographical discoveries of the second half of the 20th century.”
One thing that is known for sure about Antarctica’s network of subglacial waterways is that they are not some insignificant sideshow to the grand drama of the continent’s ice sheets. In fact, learning about the lakes and rivers could shed light (albeit from a very dark place) on weighty matters ranging from ice-sheet stability—how much do the lakes enhance the flow of ice toward the sea?—and the history of glaciation in Antarctica—did some lakes form before the ice?—to the continent’s contribution to rising sea levels. According to a recent National Research Council report, the discovery of subglacial lakes “opened an entirely new area of science in a short period of time.”
