How well do current climate models simulate the linkage between Arctic warming and extratropical cold winters?

Abstract

Recently, there has been increasing evidence that Arctic warming and extreme cold events over the northern continents are intimately related. Here, we examine how well current climate models simulate the observed relationship between Arctic warming and extratropical cold winters based on historical simulations of the Coupled Model Intercomparison Project Phase 5 (CMIP5). It is shown that most climate models simulate the observed relation reasonably well. In the models, the regional centers of the observed Arctic warming such as the Barents–Kara Seas and the East Siberian–Chukchi Seas are closely associated with the cold winters over East Asia and North America, respectively. However, we also found significant diversity among models. Analyses from the inter-model diversity suggest that atmospheric teleconnection patterns, such as the eastward expansion of the surface high and downstream development of the upper-level cyclonic flow, are keys to the link between Arctic variation and extratropical climate. Temperature budget analysis reveals that these two lower- and upper-level circulations contribute to the leading anomalous cold advection into the downstream regions.