怒江中上游流域降水趋势和周期变化分析

Precipitation Trend and Cycle Analysis of Upper and Middle Reaches of Nujiang River Basin

基于怒江贡山水文站以上流域1958～2008年降水资料,运用M-K检验法及Morlet小波函数方法,分别对该流域的年降水和四季降水序列进行了趋势和周期分析,揭示了该流域各降水系列均有增加的趋势,其中年降水系列和春季、冬季降水系列增加趋势明显,并确定了各降水系列的震荡主周期。由此预测未来3～5年内怒江中上游流域年降水和夏季、秋季降水处于偏枯期,春季、冬季降水处于偏丰期。

In this study, M-K test and Morlet wavelet function are utilized in the trend and cycle analysis of annual and seasonal precipitation series from 1958 to 2008 in the basin above the Gongshan hydrologic station of Nujiang River. It is revealed that the precipitation series of this basin are all with an increasing trend, among which, the increasing trends of annual, spring and winter precipitation series are especially obvious. The primary cycles for annual precipitation and {or precipita- tions in 4 seasons are determined, based on which, it is predicted that the annual, summer and autumn precipitations would be less than the normal in the next 3~Syears while the spring and winter precipitations would be more than the normal precipitation.