Saturday, October 8, 2011

Canadian Arctic nearly loses entire ice shelf

Two ice shelves that existed before Canada was settled by Europeans diminished significantly this summer, one nearly disappearing altogether, Canadian scientists say in new research.

The loss is important as a marker of global warming, returning the Canadian Arctic to conditions that date back thousands of years, scientists say. Floating icebergs that have broken free as a result pose a risk to offshore oil facilities and potentially to shipping lanes. The breaking apart of the ice shelves also reduces the environment that supports microbial life and changes the look of Canada's coastline.

Luke Copland is an associate professor in the geography department at the University of Ottawa who co-authored the research. He said the Serson Ice Shelf shrank from 79.15 square miles (205 square kilometers) to two remnant sections three years ago, and was further diminished this past summer.

Copland said the shelf went from a 16-square-mile (42-square-kilometer) floating glacier tongue to 9.65 square miles (25 square kilometers), and the second section from 13.51 square miles (35 square kilometers) to 2 square miles (7 square kilometers), off Ellesmere Island's northern coastline.

This past summer, Ward Hunt Ice Shelf's central area disintegrated into drifting ice masses, leaving two separate ice shelves measuring 87.65 and 28.75 square miles (227 and 74 square kilometers) respectively, reduced from 131.7 square miles (340 square kilometers) the previous year. more