历史时期广东省旱涝区域分异特征的初步研究

摘要

选取史料中1480-1940年间共460年的旱涝灾害记录,采用湿润指数法建立湿润指数(I)序列,并用最远距离法作聚类分析,讨论了广东在15-19世纪末期间总体和不同冷暖时期的旱涝区域分布状况.结果表明:1)113°E经线似乎可以看作是广东一条重要的气候特征线,该经线以东、以西的旱涝分区界线大致分别沿经向、纬向分布;2)粤西、粤北是广东旱涝区域分异变化较大的地区,粤东在不同时期也有所变化,珠三角地区则是较为稳定的涝灾多发区;3)不同冷暖时期的旱涝分区既有大致相同的特征,又有一定的差异.文章认为以上结果可能是由于广东主要受东亚夏季风影响,一定程度上也受印度夏季风影响及东亚气候系统发生改变等共同作用的结果.%Based on historical records of drought and waterlog disasters during the 15th～19th centuries in Guangdong Province,features of drought and waterlog distribution in different periods were discussed.From the analysis of the moist index(MI),we draw some conclusions as follows:1)the 113°E longitude can be regarded as an important boundary inside Guangdong Province in terms of climatic characteristics,because in the east and west of the boundary distinct differences in the distribution of regional drought and waterlog can be identified;2)the regional differentiation of droughts and waterlogs in the west and north of Guangdong changed relatively greatly in history,while in the east the change of which was not so visible,and the Pearl River Delta region kept stable as a region frequently afflicted by drought and waterlog disasters;3)in different cold and warm periods,the overall differentiations of drought and waterlog disasters shared similar pattern but still there were differences.