In January 2016 the Arctic experienced unprecedented warming, with air temperatures as high as 8°C, some 20 degrees higher than average for the time of year. Extreme warming events like this have become more common in the Arctic, contributing to the strong warming trend observed in the region. But why is the Arctic warming faster than the rest of the world? A new study indicates that warmer sea surface temperatures in the western North Atlantic may be an important driver of Arctic warming.
Currently scientists are unable to agree on the major driver of Arctic warming. A number of contributors have been suggested, including decreased surface reflectivity due to less snow and ice, increased surface turbulent heat fluxes due to thinner ice, more downward longwave radiation due to additional water vapour and clouds over the Arctic region, and poleward transport of energy via atmospheric waves.