The Cryosphere 8, 1777–1799 (2014)

Credit: KATHERINE BARNHART

Changes in Arctic sea ice will impact on coastal areas of the region. Sea ice isolates the ocean from the land in the winter, and in warmer months it limits the wind-wave activity and associated land impacts such as erosion and storm surge.

Katherine Barnhart and colleagues at the University of Colorado at Boulder, USA, use satellite data of Arctic-wide sea-ice concentrations — focusing on coastal zones —in conjunction with a case study of Drew Point, Alaska, on the Beaufort Sea, to investigate the impact of reduced sea ice. The length of the 2012 open water season, when sea ice cover is less than 15%, is found to have doubled compared with 1979, with the stormy autumn now being more ice free, allowing for greater ocean–land interactions. Drew Point is just one location along the Beaufort Coast area with rapid coastal erosion, other locations identified as hotspots for change include coastal regions in Disko Bay, Greenland and the Laptev Sea, north of Siberia and Russia. This work highlights that greater open water, and distance to the sea-ice edge, allows winds to increase water levels along large sections of the Arctic coast, resulting in the increased rate of erosion.