The growing glacier

It's hard to grasp the scale of this shot at first glance, but as the creeping clouds probably tipped you off, we're seeing something much larger than a half-frozen pond. To give you just an idea, the edges of that ice sheet rise 240 feet above the surface of Argentino Lake. Sail along the whole length of the sheer ice cliff and you'll have traveled more than 3 miles. And this is just the tip of the iceberg—er, glacier. Beyond this narrow end that feeds the 1,640-foot-deep lake, Perito Moreno Glacier covers almost 100 square miles. Even bigger news: Unlike most of Earth's glaciers, this ice giant is actually growing.