Study indicates doubling of coastal erosion rate in past 50 years along a segment of the Arctic coast of Alaska

USGS scientists recently completed a quantitative analysis, published in the July....

USGS scientists recently completed a quantitative analysis, published in the July 2007 issue of Geology, documenting effects of accelerated coastal land loss and thermokarst lake expansion and drainage along a section of the Alaska North Slope coastline.The remote sensing analysis focused on the Beaufort Sea coast, located north of Teshekpuk Lake in the National Petroleum Reserve in Alaska.  The data used in the analysis span the timeframe 1955-2005 and consisted of 1955 USGS topographic maps, and 1985 and 2005 Landsat 5 Thematic Mapper data. From these data, USGS scientists found that the rate of land loss attributed to coastal erosion more than doubled, from 0.48 km² yr–¹ during 1955–1985 to 1.08 km² yr–¹ during 1985–2005.The low-lying Arctic coastal plain north of Teshekpuk Lake hosts endangered and threatened species of waterfowl, is the calving grounds for large herds of caribou, and contains potentially significant petroleum resources.  Given competing natural resource demands in this sensitive area, land and resource managers are faced with the need to consider both the natural effects from a 30 yr warming trend that has resulted in ice-pack shrinkage and deterioration of permafrost, as well as the potential impacts of proposed human activity.The results from this quantitative analysis contribute to an enhanced understanding of the dynamic and interactive processes that shape this landscape, and provide information that is critically needed in sound land-management and policy decision making for sensitive Arctic areas