近50a新兴江流域降水变化的Morlet小波分析

Morlet Wavelet Analysis of Precipitation Changes in Xinxingjiang River Basin in the Past 50 Years

为研究新兴江流域年降水量的变化特征,采用了Mann-Kendall检验法和Morlet小波分析法对新兴江流域年降水量趋势变化及多时间尺度周期变化进行了分析。结果表明:新兴江流域年降水量先减少后增加,总体上呈不显著的上升趋势;年降水量存在枯—丰循环交替的周期变化,具有10 a和22 a尺度周期,随着时间的推移,周期震荡强度先减弱后逐渐增强。得出了新兴江流域年降水量还处于上升的趋势,随着全球气候变暖,要重视极端降雨引发的洪涝灾害等问题。

In order to study the change characteristics of annual precipitation in the Xinxingjiang River Basin,the Mann-Kendall test method and Morlet wavelet analysis method were used to analyze the annual precipitation trend and multi-time scale periodic changes in the Xinxing River Basin.The results show that:the annual precipitation in the Xinxingjiang River Basin first decreases and then increases,showing an insignificant upward trend as a whole;the annual precipitation has a cycle of dry-to-abundance alternating cycles,with 10a-year and 22a-scale cycles.As time goes by,the intensity of the cyclic shock first weakened and then gradually increased.It is concluded that the annual precipitation in the Xinxing River Basin is still on the rise.With the global warming,it is necessary to pay attention to issues such as floods caused by extreme rainfall.