Melting on Top of the World

POTSDAM – In 1845, Captain Sir John Franklin of the British Royal Navy led 128 men on two iron-plated steam ships, Erebus and Terror, into the Arctic, where they eventually disappeared. The voyage was the culmination of four centuries of failed attempts to navigate the Northwest Passage – a direct route from Europe to Asia across the Arctic Ocean – and remains one of the greatest tragedies in the history of polar exploration.

Today, a far greater Arctic tragedy is unfolding: the Arctic sea-ice cap is melting. Last month, an unprecedented new low was reached after decades of decline. Indeed, the ice cap’s area has decreased by half since the 1980’s, when summer sea-ice still extended over roughly seven million square kilometers, as opposed to less than four million today. It is now likely smaller than it has been for at least a millennium and a half.

In 2007, the Northwest Passage was ice-free for the first time in living memory. Boats of all sizes – including cruise ships – have sailed through easily in summers since then.

Walt Meier of the United States’ National Snow and Ice Data Center describes today’s ice cap as “crushed ice.” And it is getting thinner. In the last three decades, its volume has shrunk by roughly three-quarters. As the University of Laval’s Louis Fortier puts it, “we are three-quarters of the way to ice-free summers in the Arctic Ocean.”