Characteristics and Changes of Cold Surge Events over China during 1960-2007

This paper demonstrates regional characteristics, a long-term decreasing trend, and decadal variations in the frequency of cold surge events based on daily mean temperature and daily minimum temperature data in mainland China from 1960 to 2008. During these 48 years, four high frequency centers of cold surge events were located in Xinjiang, central North China, northeast China, and southeast China. A main frequency peak of cold surge events occurs in autumn for the four regions and another peak is detected in spring over northeast China and Northeast China. The regional pattern of cold surge frequencies is in accordance with the perturbation kinetic energy distribution in October-December, January, and February-April. The long-term decreasing trend (-0.2 times/decade) of cold surge frequencies in northeast China and decadal variations in China are related to the variations of the temperature difference between southern and northern China in the winter monsoon season; these variations are due to the significant rising of winter temperatures in high latitudes.