In this paper, the observed data are used to analyze the impact of ENSO events on the summer climate anomalies in East Asia, especially in the summers of 1997 and 1998. The results show that ENSO event has a significant impact on the summer climate anomalies in East Asia, especially in the Yangtze River valley. However, the impact on the summer monsoon rainfall is different in the different stage of ENSO cycle. In the developing stage of ENSO event, hot and drought may be caused in North China, and summer rainfall may be above normal in the Huaihe River Valley. On the contrary, in the decaying stage of ENSO event, severe flood may be caused in the Yangtze River valley, especially in the Dongting Lake and the Boyang Lake valleys, as in the summer of 1998. In this case summer rainfall may be below normal in the Huaihe River valley. Moreover, the extra-seasonal outlook of the SST anomalies in the equatorial Pacific is made by using the statistical method and the IAP-TPCGCM, respectively. The result shows: although it is possible that the positive SST anomalies in the equatorial Pacific may be intensified from the spring of 2002, the occurrence possibility of a new El Nino event is not large before the summer of 2002. This may is due to the weak westerly anomalies still stay over the west of the tropical western Pacific and cannot quickly propagate eastward to the equatorial central and eastern Pacific.
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