Arctic sea ice, viewed from Wahlenbergfjorden in Nordaustlandet, Svalbard. Photo: Harald Faste Aas / Norwegian Polar Institute

October 15 (NRK/Press release) – The melting of the Arctic sea ice is progressing much faster and more dramatically than earlier estimated, according to new research by the Norwegian Polar Institute (NPI). This means that the Arctic Sea could be free of ice in the summer in ten years time, rather than the 50 to 100 years estimated earlier. NPI measurements made by moored sonars show a dramatic reduction in the fraction of ridged sea ice, compared to the 1990s. The vast fields of ridged ice thicker than 5 m, constituting 28 percent of the winter Arctic sea ice cover during the 1990s, is nearly gone. At the end of winter in 2010, ice thicker than 5 m constituted only 6 percent of the total ice mass observed. The combined effect on late winter mean ice thickness is a reduction from 4.3 m ± 0.4 m during the 1990s to a record low value of 2.0 m in late winter 2010. NPI researchers speculate that increased ocean heat flux plays an important role in the thinning of the thick ice. With the thickest ice nearly gone and the MY level ice thicknesses close to thicknesses typical for first year sea ice, we are approaching a state where favorable conditions could melt most of the Arctic sea ice cover during one summer.

The Arctic Sea may be free of ice in ten years