用主分量方法分析广东春季低温阴雨年景

PRINCIPAL COMPONENT ANALYSIS OF LOW TEMPERATURE AND RAINY WEATHER IN SPRING IN GUANGDONG

本文利用主分量方法对广东47站1954～1991年2～3月平均温度和广东2～3月间低温阴雨出现年景进行统计分析，根据主分量原理，计算该时期温度的时空分布特征，直接评价低温阴雨出现年景：①广东2～3月温度时空分布极为集中，第1主分量已占埸的总方差的95．1％；③用前4个主分量及其对应的特征向量配合划分温度分布类型；③广东2～3月温度分布主要由2个类型控制，即全省一致的偏低（或高）分布和南暖北冷或南冷北暧分布．由主分量极大值（正）和极小值（负）表明：1957、1968、1969年为全省性温度偏低年，1973和1987年为全省性温度偏高年。这些年份恰好对应广东2～3月低温阴雨严重和轻微（或无）的年份。

he PCA of the Feb. - Mar. mean temperature from 1991 to 1991 at 47 stations in Guangdong and the investigation of cold and rainy weather in spring are made in this Paper. It is indicated that: 1) The spatial and temPOral distribution of Feb. -Mar. temperature is extremely concentrated, with the first principal component accounting for 95. 1 percent of the total variance ; 2)The distribution Patterns of temperature can be differentiated by using the first four principal comPonents with corresponding eigenvectors; 3) The Feb. -Mar. temperature distribution patternscan be classified into tWo types, which are (a) cold or warm in the whole province, and (b)warm south--cold north or cold south--warm north in the Province; 4 ) The maximum and minimum values of pricipal component indicate that 1957, 1968 and 1969 are lower temperatureyou, while 1973 and 1987 are higher temperatUre years. They respectively correspond to heavyor slight cold damages on crops in Guangdong.