一、引言早在50年代初,我国从事气象工作的研究人员,就已提出太平洋海水温度异常对我国汛期降水有着重要影响,并且在这方面的研究中,作出了不少的论述。近年来,随着海洋研究工作的迅速发展,海洋作用越来越引起有关研究人员的注意,尤其在长期天气预报的研究中,海洋作用已成为不可忽视的重要因素。目前,在对长江中下游汛期降水的长期预报研究中,大 I. INTRODUCTION As early as the early 1950s, researchers engaged in meteorological work in China have proposed that the temperature anomalies of the Pacific Ocean have an important impact on precipitation in China in flood season. Many discussions have been made in this aspect. In recent years, with the rapid development of marine research, the role of the oceans has drawn more and more attention from researchers. Especially in the long-term weather forecasting, the ocean has become an important factor that can not be ignored. At present, in the long-term forecast of rainfall in the middle and lower reaches of the Yangtze River, large