Formation and Melting of 'Alien' Arctic Sea Ice

As the summer sea ice diminishes in the Arctic, pressures to develop the region will increase. From shipping to resource extraction and tourism, countries will have expanded interests in exercising rights over their Exclusive Economic Zones (EEZ), extending 200 nautical miles offshore. In winter, sea ice will still continue to form over vast regions, including these continental shelves. Should the ice become contaminated from marine or atmospheric sources, it is important to understand where it will melt, potentially releasing any contaminant load.

Satellite images were analyzed to determine the origin and melt locations of 'alien ice' which melted outside the EEZ of its origin. Not surprisingly, sea ice with the greatest likelihood of being advected, was located at the downstream border of that EEZ. The largest sources of alien ice were western Canada and western Alaska in the Pacific sector, and western Russia in the Atlantic sector. Alien ice melting was most extensive in the Beaufort, Chukchi and Barents seas, as well as the East Greenland Current. Between the decades of the 1980s and 2000s, both formation and melting of alien ice increased significantly. Because most Arctic sea ice both forms and melts over the continental shelves, it is important to consider its dynamic nature when planning any future arctic development.