Sapphire Blue Melting Ponds on Arctic Ice

When the air warms up and the sunlight beats down on Greenland's ice sheet each spring and summer, marvelous sapphire-colored ponds form up like swimming pools. Melting water from glaciers flows in channels and streams and collects in depressions on the surface that are sometimes visible from space. These melt ponds and lakes sometimes disappear quickly - a phenomenon that scientists have observed firsthand in recent years.

The natural-color image above was acquired on July 4, 2010, by the Advanced Land Imager on NASA's Earth Observing-1 (EO-1) satellite. This glacial ice field lies in southwestern Greenland, not far from Disko Bay (Disko Bugt in Danish) and Davis Strait. The center of the image is 68.91* North latitude and 48.54* West longitude.