中文摘要：

利用地表湿润指数,辅以线性趋势、累积距平、Morlet小波分析、M-K突变检验等气候诊断方法,分析了1959-2013年安康地表干湿变化趋势、周期性及突变特征,为认识全球气候变化的区域响应,改善区域农业生态环境等提供科学参考。结果表明：（1）1959-2013年,安康多年平均地表湿润指数在波动中略呈上升趋势（变化倾向率为0.07/10a）。（2）春季是近55 a相对湿润的季节,但有显著的趋干倾向;夏季也是相对湿润的季节,且有显著的趋湿倾向;秋季和冬季分别是最湿润和最干旱的季节。（3）地表湿润指数在年际和季节变化上存在多时间尺度周期振荡特征,其中年际地表湿润指数变化的第1主周期是28 a,而春、夏、秋、冬四季地表湿润指数变化的第1主周期分别是17a,28a,16a,21a。（4）地表湿润指数在近55 a表现出明显的突变。

英文摘要：

This article aims to Province from 1959 to 2013, analyze the change of dry-wet condition surface and its cycles in Ankang of Shaanxi to provide reference for understanding the regional response and mechanism to the global climate changes and the improvement of the agricultural ecologic environment. The daily data of Ankang from 1959 to 2013 were collected to analyze the temporal change of the dry-wet condition by using the methods of humidity index, Morlet complex wavelet and Mann-Kendall test and so on. The results showed that, the surface humidity index of Ankang is slightly increasing in fluctuation and the rate of the change of which is 0.07/10a; spring and summer have relative humid climate in recent 55 years, but there are obvious aridity trend in the spring and obvious humidity midity in 21a, for index in in the summer; there exists Ankang, in which the first spring, the past Sllnlnler, 55 years major annual cyc with muhiple time scales of annual and seasonal hule are 28a, and seasonal cycles are 17a, 28a, 16a. there are obvious abrupt changes of surface humidity