John Walsh, University of Alaska
Sparsely populated, the Arctic has few weather stations and lacks a long record of climate observations, but even these limited data show that the region is highly sensitive to the effects of greenhouse gases. Temperatures in the Arctic are warming faster than any other region on Earth, especially in winter. The resulting dramatic losses of sea ice and thawing permafrost, glaciers, and ice sheets feed back to the global climate and amplify the effects of warming. At the same time, the region’s climate varies widely from year to year and from place to place, making it challenging to predict the future and critical to make the most of the information we have.