中文摘要：

采用桑斯维特在气候分类法中定义的干湿指数,结合趋势系数分析、小波分析、M-K检验等统计方法,对吉林省近50年气候干湿变化状况进行了分析.结果表明：吉林省表现出4次相对的干湿交替,即20世纪60年代的偏湿润期,70年代的相对干旱期,80年代的偏湿润期,90年代中后期以后的偏干旱期;存在10～15a和3a的变化周期,突变发生在1979—1980年;在空间变化上表现出湿润区范围不断扩大,半湿润区显著缩小,半干旱区范围略有扩大的特点.

英文摘要：

In this paper, we analyze the climatic drought-wet change over Jilin in the past 50 years using the dry wet index defined by Thonthwaite,combined with the trend coefficient, wavelet transform and M-K test. The results show that the interdecadal climatic variation experience four alternating dry and wet periods, including course of wet period in the 1960s,dry period in the 1970s,wet period in the 1980s, and dry period after mid90s,respectively. The periods of 10-15a and 3a exist. The mutation point occurs between 1979 and 1980. Humid areas expand,whereas semi-humid areas reduce significantly. The semi-arid areas slightly expand.