New Insight from Old Snapshots of Greenland

From NASA's Earth Observatory:

Historic photographs show glacial retreat since the early 1900s. In the example shown here, the images show changes to a glacier in the vicinity of the Sukkertoppen ice cap in southwest Greenland. By summer 2013 (top), the glacier had retreated by about 3 kilometers (less than two miles) since summer 1935 (bottom).