Atmospheric Circulation Features of Winter Lower Temperature in Chongqing in 2008

Based on the meteorological data of daily temperature and rainfall data observed by 34 meteorological stations, and the daily mean reanalysis data of NCEP/NCAR (from January 11th to February 3rd) in 2008, the atmospheric circulation features of winter lower temperature in Chongqing are studied.The result indicates that the anomalous atmospheric circulation feature in high and low latitude over Asian leads to the lower temperature in Chongqing in 2008 early.The anomalous of Asian Polar Vortex, Ural Blocking and Siberian High over middle-high latitude made the strong cold air accumulating in Siberia, then the strong cold air entered in China from Siberia and Mongolia with Mongolia Cold High effecting.The cold air and the warm air from the low latitude encountered and formed the convergent zone over Yangtse River.The equiponderant cold air and warm air were keeping in South China which made the large area appearing the lower temperature weather.