DIAGNOSTIC ANALYSIS OF THE INFLUENCE OF ANOMALOUS SURFACE SENSIBLE HEAT FLUX IN THE TIBETAN PLATEAU AND ITS VICINITY ON THE EAST ASIAN WINTER MONSOON

摘要

Based on NCEP/NCAR reanalysis monthly data,the relation between the surface sensible heat flux,(SHTFL) in the Tibetan Plateau and its vicinity and the East Asian winter monsoon is revealed as follows:on the inter-annual and longer time scales,the difference between SHTFL anomalies in the east and southern slope of the Tibetan Plateau last spring has influence on the East Asian winter monsoon,that is,SHTFL anomaly in the east of the Tibetan Plateau was positive and that in the southern slope was negative last spring,then the East Asian winter monsoon would become more vigorous,and vice versa.Both the most significant period of the difference between SHTFL anomalies in the east and southern slope of the Tibetan Plateau and that of the East Asian winter monsoon index are 2 to 4-year time scales.On the 2 to 4-year time scales,the heterogeneous spatial distribution of SHTFL anomalies in the east and southern slope of the Tibetan Plateau last spring has effect on the East Asian winter monsoon,after SHTFL anomaly in the east of the Tibetan Plateau was positive and that in the southern slope was negative last spring,then the East Asian winter monsoon would be more powerful,and vice versa.The lag influence of the difference of SHTFL anomalies in the east and southern slope of the Tibetan Plateau on the East Asian winter monsoon brings into effect mainly on 2 to 4-year time scales.In the end an reasonable explanation for their relationship has been discussed.