The Retreating Alsek Glacier, Alaska

The Alsek Glacier, located in the remote wilderness of Alaska, has undergone dramatic transformations over the last few decades. As the climate has warmed, the glacier’s tongue has retreated and thinned, giving way to the expansion of a proglacial lake at its terminus. Because this dynamic landscape is difficult to monitor continuously from the ground, the historical record of the Landsat program provides critical insights into the rate of ice loss and the shifting features of the region.