ANOMALOUS WINTER CIRCULATION AT 1000hPa OVER EAST ASIA AND ITS RELATION TO CLIMATE CHANGE OVER CHINA

The relationship between the spatial and temporal variation characteristics of the first mode(EOF1) of East Asian winter monsoon and climate change in China is revealed by using the vector EOF expansion of winter wind fields at 1 000 hPa over East Asia during 1951/1952～2003/2004.Study shows that EOF1 time coefficient can represent the intensity change of the East Asian winter monsoon well.The high(low) EOF1 time coefficient is associated with cold and dry(warm and rainy) winter,which gives rise to cold(warm) spring in the Great Bend area of Yellow River and northeast China,dry(rainy) summer in the lower and middle reaches of the Yangtze River while climatic conditions are opposite in North China and South China areas,higher(lower) temperature occurring over the Yangtze River valley and lower(higher) temperature over southern and southwestern China.