The Markham Ice Shelf, once located on Ellesmere Island in Canada, has broken away and drifted into the Arctic ocean.
Background
The Markham Ice Shelf was one of five ice shelves remaining on Ellesmere Island. During the last century, the single ice shelf that once covered the island has retreated over 90%, covering just under 400 square miles at the start of the 2008 summer. During the summer the Searson Ice Shelf and the Ward Hunt Ice Shelf have also lost large chunks of ice.BBC News: Major ice shelf loss for Canada (September 3, 2008)