"A few years ago, scientists were predicting that Arctic waters would be ice-free in summers by about 2080.

Then computer models started projecting earlier dates, around 2030 to 2050.

Then came the 2007 summer that saw Arctic sea ice shrink to the smallest extent ever recorded, down to 4.2 million sq km from 7.8 million sq km in 1980.

By the end of last year, one research group was forecasting ice-free summers by 2013.

"I think we're going to beat last year's record melt, though I'd love to be wrong," said Dr Stroeve.

"If we do, then I don't think 2013 is far off any more. If what we think is going to happen does happen, then it'll be within a decade anyway.""

© BBC News/Euronews