中国东部季风区夏季雨型的划分及其环流成因分析

在总结前人关于中国夏季雨型划分的研究成果及其存在的主要问题的基础上 ,对中国夏季雨型的划分进行了新的尝试。根据东部季风区夏季 ( 6～ 8月 )降水的客观气候规律及业务预报应用需要 ,利用经验正交分解、主成分分析、奇异值分解、聚类分析等数理统计方法 ,结合经验分析 ,对中国东部季风区 1 880年以来 1 2 0多年夏季降水进行了客观分型 ,将中国东部季风区夏季降水划分为两类四型 ,并进一步分析了各类雨型的大气环流成因。

STUDY OF SUMMER RAIN PATTERN IN MONSOON REGION OF EAST CHINA AND ITS CIRCULATION CAUSE

On the foundation of research and some problems of summer rain pattern by predecessors, a new trail on summer rain pattern is carried on. According to the objective climate regulation and vocational applications to predicting summer rainfall in the monsoon region of the east China, and using some statistics methods such as Empirical Orthogonal Function(EOF), Principal Component Analysis(PCA)?Singular Value Decomposition(SVD) and ISODATA fuzzy cluster method based on more than 120 years since 1880, and combines the experience analysis , the precipitation of the monsoon region of the east China can be divided into two kinds (E1 and E2) and four hypo-kinds (E1a?E2b?E2c and E1d): One kind (E1) of precipitation distribution is more for North and South and lack for the middle area, the major rain belt of E1a is located over the valley of the Yellow River and the North China, and the major rain belt of E1d is located over the south of the Yangtze River and the South China. Another kind (E2) of precipitation distribution is lack for the North and the South and more for the middle area, the major rain belt of E2b is located over the valley of the Huaihe River, and the major rain belt of E2c is located over the valley of the Yangtze River. Also different kinds of atmospheric circulation cause of rain pattern are analyzed, and it shows that rain pattern has good indication for short-range climate prediction in the monsoon region of the east China.