A pioneering expedition to the North Pole, during which a team trekking across the Arctic Ocean drilled 1,500 holes in the ice, has found that most of the ocean is covered by thinner, first-year ice, leading scientists to forecast that the ocean will be largely ice-free in summer within a decade or two. The Catlin Arctic Survey, carried out last spring as the expedition trekked for 73 days across 280 miles of the northern Beaufort Sea to the North Pole, determined that the average thickness of ice in the area was
close to six feet. Analyzing the data, ice experts said that much of the sea ice is only about a year old, replacing the thicker ice, formed over many decades, that once covered the sea. Measurements made by nuclear submarines in the 1950s showed that much of the northern Beaufort Sea was once covered by multi-year ice that was twice as thick. “With a larger part of the region now first-year ice, it is clearly more vulnerable,” said Peter Wadhams of the Polar Ocean Physics Group at Cambridge University. “The area is more likely to become open water each summer.” Within 10 to 20 years, Wadhams said, the Arctic Ocean “will essentially be an open sea in the summer.”
Catlin Arctic Survey