Overall warming of the Arctic is at a much more rapid pace than the rest of the world. This accelerated pace of warming is due, in large part, to loss of snow and sea ice reflectivity during the Spring and Summer months. As a result, more heat is absorbed into dark land and ocean surfaces — a heat that is retained throughout the Arctic over longer and longer periods. And, though NOAA doesn’t report it in the above video, overall higher concentrations of greenhouse gasses like methane and CO2 in or near the Arctic region also contribute to a higher rate of warming (see NOAA’s ESRL figures). In a world that is now rapidly proceeding beyond the 400 ppm CO2 and 485 ppm CO2e threshold, this is exactly the kind of Northern Hemisphere polar amplification we would expect to see.

From: robertscribbler.com