The North Pole could be ice-free this summer for the first time in recorded history, a US scientist warned Friday.
Mark Serreze, a geophysicist with the Colorado-based National Snow and Ice Data Center, said in interviews broadcast throughout the day that the Arctic ice shows signs of melting even faster than last year's record melt.
The verdict won't be in until September, when Arctic ice historically reaches its thinnest point after the long, bright summer. The ice is thickest in March.
But Serreze told US broadcasters that the region has already lost ice the size of California this year, and the chances were 50-50 that the North Pole would melt this summer.
"We're probably 20 to 30 years ahead" of where scientists thought the melt would be when they started raising alarm some 30 years ago, Serreze said.
"Almost all of our water supply for agricultural use and municipal use comes from the melt of the winter snowpack," Serreze noted.
Earlier this week, Serreze told Canwest News Service in Canada that a great deal depended "on the weather patterns that set up this summer. Will we have a 'perfect storm' like last summer, or some other pattern that helps to preserve ice?"
After last year's record melt, the so-called Northwest Passage was briefly ice-free by September 2007. New ice built up during the cold winter, but one-year ice is more susceptible rto melting than century-old ice masses, Serreze noted.
His comments strengthened growing concern about the rapid pace of global warming blamed on carbon emissions from burning fossil fuels.
Earlier this week, three Nordic royals - Norway's Crown Prince Haakon, Sweden's Crown Princess Victoria and Denmark's Crown Prince Frederik - travelled to the North Pole aboard an ice-breaker to get as close to possible to the Arctic center to observe first hand the environmental problems.