Arctic sea ice shrinks to lowest level on record

Arctic sea ice has melted to its minimum extent for the year due to climate change, setting a record for the lowest summer cover since satellites began collecting data.

The 2012 extent has fallen to 3.41 million sq km, which is 50 per cent lower than the 1979-2000 average.

Arctic sea ice has long been regarded as a sensitive indicator of changes in the climate, NSIDC said in a statement.

Scientists who have been analysing the startling melt think it is part of a fundamental change.

This year’s minimum caps a summer of low ice extents in the Arctic.

On August 26, sea ice extent fell to 4.10 million sq km, breaking the previous record low set on 18 September 2007 of 4.17 million sq km.

It fell below four million sq km on September 4, another first in the 33-year satellite record.

Scientists say they are observing fundamental changes in sea ice cover. The Arctic used to be dominated by multiyear ice that survived through several years.

The region is characterised by seasonal ice cover and large areas are now prone to completely melt away in summer.

The sea ice extent is defined as the total area covered by at least 15 per cent of ice, and varies from year to year because of changeable weather.

However, ice extent has shown a dramatic overall decline over the past 30 years.

NSIDC lead scientist Ted Scambos said that thinning ice, along with early loss of snow, are rapidly warming the Arctic.