NOAA Map of Low Sea Ice Concentration
Seasonal sea ice loss began exceptionally early this spring in the Chukchi Sea near Alaska. While, during the spring, open water areas are common offshore of Alaska’s northwest coast, this year the area of very low concentration ice grew rapidly during the first half of May. By May 15, there was open water as far north as 72°N and extended, in places, 100 miles west of the coastal shorefast ice. In recent times, 2008 is the only vaguely similar year, when there was considerable open water by mid-May south of 70°N. However, this large an area of open water, at this point in the year, appears to be unprecedented. This remarkable event is due to a combined influence of both atmospheric and oceanic factors, such as the unusually mild winter that northern Alaska experienced, and the fact that there was virtually no multi-year ice in the eastern Chukchi Sea this winter.