The Milne Ice Shelf on the northwest coast of Nunavut’s Ellesmere Island has broken up, reducing in size by almost half and setting large ice islands adrift in the Arctic Ocean. The 4,000-year-old feature shattered in July, taking with it almost half of the ice shelf and plummeting 81 square kilometres of ice into the surrounding ocean. One large ice island was created at that time, but it split into two large chunks, along with numerous smaller icebergs.
Carleton University’s Derek Mueller, professor in the Department of Geography and Environmental Studies, explains, “Our research focus is to learn more about how ice shelves destabilize and break up in a warming climate.” The researchers were unable to be in the field this summer due to pandemic restrictions, but used satellite images to track the event.
The Milne Ice Shelf is the most recent of Canada’s ice shelves to deteriorate. At the start of the 20th century, there was a single ice shelf, one-and-a-half times larger than Prince Edward Island, stretching along the northern coast of Ellesmere Island. By 2000, it had divided into six large ice shelves and several minor ones. The Milne Ice Shelf was considered to be one of the least vulnerable since it is well-protected in Milne Fiord, but it sustained many fractures over the past 12 years.
“This drastic decline in ice shelves is clearly related to climate change,” says Luke Copland, research chair in Glaciology in the Department of Geography at the University of Ottawa. “This summer has been up to 5°C warmer than the average over the period from 1981 to 2010, and the region has been warming at two to three times the global rate. The Milne and other ice shelves in Canada are simply not viable any longer and will disappear in the coming decades.”
Mueller and Copland’s research into ice shelf changes is funded by the Natural Sciences and Engineering Research Council of Canada, the Polar Continental Shelf Program and ArcticNet.