两类ENSO事件前期的热带太平洋海温距平场

ANALYSIS OF THE OCEANIC FEATURE IN THE TROPICAL PACIFICOCEAN ONE YEAR BEFORE ONSET OF THE TWOTYPES ENSO EVENT

分析了１９５６年以来两类ＥＮＳＯ事件热带太平洋海温距平场的特征，结果指出，东部型Ｅ１Ｎｉｎｏ事件前期为ＬａＮｉｎａ事件年，热带中东太平洋为强的海温负距平，东部型ＬａＮｉｎａ事件前期为ＥｌＮｉｎｏ事件年，热带中东太平洋为强的海温正距平；中部型ＥｌＮｉｎｏ事件前期热带中西太平洋多为明显的海温正距平，中部型ＬａＮｉｎａ事件前期热带东太平洋多为明显的海温负距平。两类ＥＮＳＯ事件前期海温距平场特征基本相反。就热带西太平洋暖池海域而言，中部型ＥｌＮｉｎｏ事件前期暖池处于偏暖状态，东部型ＥｌＮｉｎｏ事件前期则处于偏冷状态。西太平洋暖池处于偏暖状态是中部型ＥｌＮｉｎｏ事件发生的必要条件。

he oceanic feature in the tropical Pacific Ocean one year before the two types of ENSO event was analyzed. The results show that, one year before the eastern pattern El Nino events onset, the La Nina events occured, in which the SST was extremely colder than normal in eastern and central tropical Pacific Ocean; one year before the eastern pattern La Nina events onset,the El Nino events occured, when the SST was extremaly warmer than normal in eastern and central tropical Pacific Ocean. There were much warmer SST in the tropical western and central Pacific Ocean before the Central pattern El Nino events onset, and much colder SST in the tropical eastern Pacific Ocean before the central pattern La Nina events onset. Warmer SST in the tropical weatern Pacific warm pool region is an essential condition for the onset of central pattern of El Nino events.