21 Jul 2015

Arctic sea ice grows after unusual summer

8:14 pm on 21 July 2015

Scientists have claimed that the volume of Arctic sea ice has increased by about a third, after an unusually cool summer in 2013.

The researchers said the growth continued in 2014 and more than compensated for losses recorded in the three previous years.

The scientists involved believe changes in summer temperatures have greater impacts on ice than thought.

A picture by NASA's Aqua satellite taken on September 3, 2010 shows the Arctic sea ice. The Arctic Ocean's dynamic layer of sea ice that grows each winter and shrinks each summer, reaching its yearly minimum size each fall. The ice cools the planet by reflecting sunlight back into space.

A NASA satellite picture of the Arctic sea ice from September 2010 Photo: AFP

But they said 2013 was a one-off, and that climate change would continue to shrink the ice in the decades ahead.

The scientists found that ice volume declined by around 14 percent between 2010 and 2012. But in the cooler summer of 2013, the ice grew substantially - up by a third on the average of the previous three years.

This growth in volume was sustained in 2014.

The researchers said that the more accurate measurements that they have now published show that sea ice is more sensitive to temperature changes than previously thought.

They said the cooler season had helped moderate the effects of global warming, and that 2013 was most likely an anomaly - the longer-term trend of rapid warming was still dominant.


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