Mechanisms that can potentially link fast warming in the Arctic region and extreme winter weather in the northern mid-latitudes are identified in a review article published online in Nature Geoscience. However, how large the influence of Arctic ice and snow decline is on mid-latitude winter weather remains highly uncertain.
Judah Cohen and colleagues reviewed the literature on potential links between the amplified warming in the Arctic region and extreme weather events, and identified potential pathways of influence. Specifically, they suggest that a weaker temperature gradient between the Arctic and mid-latitudes could lead to changes in key features of the northern hemisphere atmosphere, such as the jet stream and the storm track. A weaker gradient could also alter the ways in which energy is transported by large-scale atmospheric waves. These changes, in turn, have the potential to influence the occurrence of mid-latitude weather extremes like the persistent cold conditions that hit the United States during winter 2013/14. However, the authors caution that better models and observations are required to quantify the strength of this influence.