塔里木盆地西缘山地降水量变化特征研究

基于塔里木盆地西缘山地1960~2015降水量数据,采用Mann-Kendall(M-K)趋势检验、线性趋势分析、多项式拟合、移动平均、Morlet小波函数和滑动t检验(MTT)等方法分析了其降水变化趋势、变化过程、变化周期和突变情况。结果表明,塔里木盆地西缘山地以夏秋降水为主,年降水量和四季降水量在波动中整体呈上升趋势,其中年降水量、夏秋季节降水量递增速率快、趋势显著,这些变化将加大防洪压力,必须引起重视;年降水量、四季降水量存在准4、8、12、28年周期波动,但模方系数变化较大,表明年降水量和不同季节降水量波动周期的主控因素不同,不同时段降水量波动周期的主控因素也不同;年、春季、夏季、秋季和冬季降水突变点分别为1985、1977、1986、1997、2000年,突变前后降水量平均值变化明显。研究结果对于防洪防汛、水资源合理利用及山区或河流上游修建水库设计具有一定借鉴价值。

Variation Characteristics of Precipitation in Western Mountains of Tarim Basin

Based on the precipitation data of western mountains of the Tarim Basin from 1960 to 2015, variation trends, change process, periodic oscillation and abrupt changes of precipitation are evaluated by climate diagnosis methods include Mann-Kendall trend test(M-K), linear trend analysis, polynomial fitting, moving average, Morlet wavelet analysis and Moving t test(MTT). The results show that the precipitation of mountains in west margin of the Tarim Basin concentrated in summer and autumn. Whole process is on the rise trends in fluctuation of annual precipitation and seasonal precipitation. The increasing rate of annual precipitation, precipitation in summer and autumn were largest and appeared the most significant changes. These changes will increase the pressure of flood control, which should be paid attention to. The presence of annual precipitation and seasonal precipitation change exist 4 a, 8 a, 12 a and 28 a cycles. However, the change of modulus coefficient is large, which demonstrates that the main controlling factors of precipitation and fluctuation period of precipitation in different seasons are different. The main controlling factors of precipitation fluctuation cycle in different periods are also different. Annual precipitation, precipitation in spring, summer, autumn, and winter abrupt time was occurred in 1985, 1977, 1986, 1997 and 2000, the changes of average precipitation before and after the abrupt are obvious. The research results will be of reference value for flood control, water resources rational utilization and reservoir design in mountainous areas or the upstream rivers.