西南地区暴雨时空分布特征分析

Spatial and temporal distribution characteristic in the southwest

利用西南地区102个气象站1961~2010年逐日降水资料,采用趋势分析、Mann-Kendall突变检验、小波分析等方法分析了50a西南地区的暴雨时空分布特征。结果表明:时间上,西南地区极端暴雨降水事件各个指标均呈现增加的变化趋势,突变主要发生在1986年前后,该地区年平均暴雨存在4个变化的周期;空间上,年均暴雨频次在暴雨量空间上呈现由西北向东南增加的趋势,暴雨频次及暴雨量较高的地区集中在广西地区,而四川西部及云南大部分地区暴雨频次较小。

Based on the daily precipitation data of 102 meteorological stations in the southwest China from1961 to 2010,some methodologies were used,such as trend analyses method,Mann-Kendall test method and wavelet analysis method,to analyze the spatial and temporal characteristic of rainstorm in the southwest during 50 years.It is showed that each indicator of extreme rainstorm events in the southwest presented an increasing trend from 1961~2010,during which there were 4 variation periods.And mutation occurred around 1986.The frequency of annual average rainstorm presented an increasing trend from northwest to southeast.Higher frequency of rainstorm was detected in the Guangxi while the lower frequency of rainstorm was detected in the west of Sichuan and most parts of Yunnan.