Arctic ice shrinks 18%, alarm bells are ringing!

Sea ice in the Arctic shrank a dramatic 18% this year on the previous record set in 2007 to a record low of 3.41m sq km, according to the official US monitoring organisation the National Snow and Ice Data Centre in Boulder, Colorado.

Scientists and environment groups last night said the fall was unprecedented and the clearest signal yet of climate change.

The data released showed the arctic sea beginning to refreeze again in the last few days after the most dramatic melt observed since satelliteobservations started in 1979.

This year's sea ice extent was 700,000 sq km below the previousminimum of 4.17m sq km set in 2007.

"We are now in uncharted territory," said Nsidc director Mark Serreze. "While we've long known that as the planet warms up, changes would be seen first and be most pronounced in the Arctic, few of us were prepared for how rapidly the changes would actually occur."

Julienne Stroece, an Nsidc ice research scientist who has been monitoring ice conditions aboard the Greenpeace vessel Arctic Sunrise, said the data suggested the Arctic sea ice cover was fundamentally changing and predicted more extreme weather.

"We can expect more summers like 2012 as the ice cover continues to thin. The loss of summer sea ice has led to unusual warming of the Arctic atmosphere, that in turn impacts weather patterns in the northern hemisphere, that can result in persistent extreme weather such as droughts, heatwaves and flooding," she said.