里下河地区降雨量多时间尺度分析

Multiple-time Scale Analysis of Precipitation in Lixiahe Region

小波分析是一种时频多分辨分析方法,成为近年来研究水文要素长期变化的层次规律和特征的重要方法。本文应用小波分析方法对里下河地区1953～2005年降雨量及最大连续15d降雨量趋势进行探讨,得出了里下河地区的年降雨量序列存在着26年、15年和6年的多时间尺度的周期变化,其最大15d降雨量序列明显存在21年左右的周期变化,进而得出在2003～2012年期间,其涝灾机率会增多的结论。

As a time and frequency analysis method, wavelet analysis has been used to study the rule and characteristics of the long-term change of hydrologic factors. This paper used the wavelet analysis method to study the annual rainfall series and maximum consecutive 15 days rainfall series of Lixiahe Region in Jiangsu Province from 1953 to 2005. The results show that the annual rainfall series exist 26, 15 and 6 years period, and the maximum consecutive 15 days rainfall series exist 21 years period. As a result, a conclusion was made that the probability of flood would obviously increase in Lixiahe Region during the period from 2003 to 2012.