A DIAGNOSIS OF THE INTERANNUAL VARIABILITY OF SEA SURFACE TEMPERATURE AND SURFACE WIND FIELD IN THE TROPICAL OCEANS AND ITS CORRELATIVE CHARACTERS WITH ENSO CYCLE

Utilizing the NCEP/NCAR reanalysis monthly datasets,and based on the filter and standard deviation calculation,the interannual variability of sea surface temperature(SST)and 1000 hPa wind field for the tropical Pacific,Indian and Atlantic Oceans is investigated for the past 20 years (1979—1998).The characters of space-time evolution in SST anomalies(SSTA)for each ocean and corresponding wind anomaly field are acquired by using rotated principal component(RPC) and linear regression analysis methods.Using the method of correlation analysis.the characters of three tropical oceans correlated with ENSO are investigated.The contemporary correlation between the SSTA in the Indian Ocean and in the equatorial eastern Pacific is positive,and there is a weak negative correlation between the SSTA in the equatorial east Atlantic Ocean and in the equatorial eastern Pacific.The lead-lag correlation analysis indicates that the SSTA in the equatorial Indian Ocean lags the dominant Pacific ENSO mode by 3 months,and the SSTA in the equatorial Atlantic Ocean leads ENSO mode by 6 months.The ENSO-correlated components in tropical Indian Ocean and tropical Atlantic Ocean display much the same amount of total variance in each ocean,i.e..14% in the Indian Ocean and 12% in the Atlantic Ocean and the maximums are all above 40%.