"OTTAWA -- The multiyear ice covering the Arctic Ocean has effectively vanished, a startling development that will make it easier to open up polar shipping routes, an Arctic expert said on Thursday.
Vast sheets of impenetrable multiyear ice, which can reach up to 80 meters (260 feet) thick, have for centuries blocked the path of ships seeking a quick short cut through the fabled Northwest Passage from the Atlantic to the Pacific. They also ruled out the idea of sailing across the top of the world.
But David Barber, Canada's Research Chair in Arctic System Science at the University of Manitoba, said the ice was melting at an extraordinarily fast rate.
'We are almost out of multiyear sea ice in the northern hemisphere,' he said in a presentation in Parliament. The little that remains is jammed up against Canada's Arctic archipelago, far from potential shipping routes.
Scientists link higher Arctic temperatures and melting sea ice to the greenhouse gas emissions blamed for global warming."