By Sid Perkins
Rates of erosion along Alaska’s northern coast have more than doubled in recent decades, overhead views suggest.
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Mud-rich permafrost cliffs standing 3 to 4 meters tall constitute much of the shore that runs from Barrow, Alaska, to the Canadian border. In some spots, the coast has moved inland more than 900 m during the past 50 years, says John C. Mars, a geologist with the U.S. Geological Survey in Reston, Va. He and USGS colleague David W. Houseknecht compared an aerial survey conducted in 1955 with more-recent satellite images to gauge erosion along the Arctic Ocean coastline.