Snow cover lingered in the Great Lakes region on February 16, 2008. Against the backdrop of snowy ground appear the deep blue waters of the Great Lakes and nearby water bodies. In this wintertime shot, the lakes are relatively ice-free, except for Lake Erie.
Across the rippling, crevassed whitescape of the East Antarctic Ice Sheet, two unusual shapes appear in this grayscale satellite image of the frozen continent.
Huge sheets of ice carved out the U-shaped valleys that hold New York’s Finger Lakes. When they retreated north about 10,000 years ago, glaciers left deposits of gravel that dammed streams and caused the depressions to become lakes.