With one month of the summer melt season remaining, the area covered by Arctic sea ice is already only 2.02 million square miles, less than at any time since records began in the 1970s.
‘This is very strong evidence that we are starting to see an effect of greenhouse warming,’ Mark Serreze, a senior research scientist at the NSIDC, told Associated Press.
At current rates, the Arctic will be sea ice free in summer by 2030. This is faster than some computer climate models predict – they expect that it will be 2070 before Arctic sea ice melts completely during the summer.
Dr Joy Singarayer, a sea ice expert at Bristol University, told the Ecologist:
‘Loss of Arctic sea ice could have consequences for climate and climate variability that are more widespread than the Arctic, as well as for the ecosystems and communities that inhabit the Arctic itself.’
As the sea ice disappears, polar bears face starvation since they depend on sea ice to reach and hunt seals. The Gulf Stream, the current that brings warm water to the west of Europe, could also be affected. It is driven by dense, salty water sinking to the bottom of the ocean near Greenland and, as Arctic sea ice melts and reforms throughout the year, it affects the saltiness of the underlying ocean.
Scientists also believe that declining Arctic sea ice cover could cause decreased rain and snowfall in the American west, and torrential winter rainfall over parts of Europe.
This article first appeared in the Ecologist August 2007