Beaufort coastal erosion accelerating

The rate of erosion of the Beaufort Sea coast north of Teshekpuk Lake in the National Petroleum Reserve-Alaska more than doubled between 1955 and 2005, according to a U.S. Geological Survey report by scientists John Mars and David Houseknecht. “Quantitative Remote Sensing Study Indicates Doubling of Coastal Erosion Rate in Past 50 Years Along a Segment of the Arctic Coast of Alaska” appeared in the July issue of the Geological Society of America’s “Geology” journal. An analysis of Landsat satellite imagery and topographic maps compiled from aerial photographs found as much as 0.9 kilometers (0.6 miles) of coastal erosion in some areas in the past 50 years. That erosion has drained and re-flooded Arctic lakes with seawater, and has impacted wildlife and human infrastructure, USGS has said.

“This area’s increased rate of coastal erosion over these time increments may be the result of greater wave action caused by earlier seasonal melting and reduced size of the Arctic ice pack, which warrants further study,” said Mars. “Since beaches are absent or poorly developed along most of the studied coast, there is little, if any, protection against this increased wave energy. As a result, the waves undercut the mud-rich permafrost land, causing it to collapse into the sea. As the permafrost blocks melt, the muddy sediment they contain is resuspended in the water and carried offshore.”