RECONSTRUCTION OF EL NINO EVENT CHRONOLOGY FOR THE LAST 600 YEAR PERIOD

The El Nino events for 1870-1989 were identified according to the sea surface temperature(SST)over the eastern equatorial Pacific(0-10°S,90-180°W)and Southern Oscillation Index.The chronicle of the El Nino events in historical time(14708-1879)was reconstructed by using of a series of proxy data such as Australian droughts,Nile floods,Peruvian floods,numbers of landing typhoon in China,cool summers in East Asia,SOI calculated from tree ring data,and El Nino events identified mainly from meteorological and oceanographical conditions along the Ecuador and Peru coast.Finally,114 El Nino events were found for the period 1470-1989.The mean return interval was 4.5 years.The frequency of the events seems to have a cyclical variation of 70 years.No close relationship was found between the global warming and the frequency of El Nino events.