黄河上游月径流序列多尺度特性分析

Multi-Scale Analysis of Monthly Runoff Series in the Upper Reaches of the Yellow River

采用Hilbert-Huang变换(HHT)方法对黄河上游贵德站、小川站和兰州站的天然月径流序列进行分析,分解得到不同尺度下的固有模态函数,然后结合重标度极差(R/S)分析法分析了各阶模态函数及天然月径流量,得到Hurst指数和分维数,并对河川径流序列的波动周期性、分形特征、趋势性进行了分析。结果表明:黄河上游1929—1997年的天然月径流具有1 a以下、1.6 a、2～3 a、5～8 a、15～32 a的波动周期和自相似性及反持续的长程相关性。

According to the natural monthly runoff data of Guide,Xiaochuan and Lanzhou hydrologic stations on the upper Yellow River,the intrinsic mode functions were resolved with the Hilbert-Huang Transform,and then the Hurst index and fractal dimension were calculated with the rescaled range analysis.The results show that the natural monthly runoff data of the upper Yellow River during the period of 1929-1997 has fluctuant periods of less than 1,1.6,2-3,5-8,and 15-32 years and self-similarity and anti-persistence long range dependence.