The edges of the Ward Hunt Ice Shelf, located about 2,175 miles north of Edmonton, are melting, Canada.com reported Sunday.
The ice shelf, a 280-square-mile ledge that's 82 feet thick, reaches up from the mouth of Ellesmere Island's Disraeli Fiord.
In 2002, Derek Mueller, a PhD student at Laval University, was studying bacteria on the shelf when he discovered an enormous crack along its entire length.
The following two years produced few changes, but when he returned again this summer, Mueller discovered another sizable crack on the northern edge of the ice sheet.
Ward Hunt is the largest of five separate shelves that once comprised the 3,000-year-old Ellesmere Island Ice Shelf, which has lost 90 percent of its mass in less than a century.
When Robert Peary explored the top of Ellesmere Island in 1906, the Ellesmere Island Ice Shelf covered about 5,530 square miles. The five shelves now comprise just 559 square-miles.
Scientists say the rapid decrease is a clear signal of Arctic climate change.