Is extreme Arctic sea ice anomaly in 2007 a key contributor to severe January 2008 snowstorm in China

We conduct numerical experiments with an atmospheric general circulation model to answer the question whether the extreme Arctic sea ice anomaly in 2007 contributed to the severe January 2008 snowstorm in China. Results show that the record low Arctic sea ice in September 2007, and follow-up slow recovery of the Arctic sea ice in October and November 2007 could excite two stationary wave structures. One wave train propagates southeastward from the Barents/Kara Seas to central Asia, strengthening the Middle East Jet Stream (MEJS), and the other wave train propagates southward from central Arctic Ocean/eastern Siberia Sea to the mid-latitude and subtropics of the north Pacific, weakening the East Asian Jet Stream (EAJS). The anomalous westerlies associated with the strengthening of the MEJS and the anomalous easterlies associated with the weakening of the EAJS form a strong convergence zone over central and southern China, providing favorable conditions for the severe January 2008 snowstorm. Copyright © 2011 Royal Meteorological Society