基于TRMM 3B42数据的1998-2010年中国暴雨时空特征分析

Analysis of spatial and temporal characteristics of rainstorm in China from 1998 to 2010 based on TRMM 3B42 data

基于TRMM 3B42数据,构建5个年尺度时间序列参数,借助GIS空间分析和数学方法,揭示和分析1998-2010年暴雨降水的格局与过程特征。研究表明:13年来,年暴雨降水总量与年降水总量均呈缓慢下降的趋势,且空间格局相似,年暴雨降水比例时间波动较显著;暴雨集中分布区年降水以及年暴雨降水的时间波动均比较明显,年暴雨频次的时间波动较小但空间差异显著;暴雨降水空间分布在东西方向的差异性明显强于南北方向;年暴雨降水呈现向东北方向偏移的趋势;5个变量的变化趋势均表现出较强的空间差异性,且大部分像元呈增加(或减少)但统计不显著的趋势。

Based on TRMM 3B42 precipitation data, 5 time series at annual scale were defined. Then the spatial and temporal dynamics of rainstorm were evaluated by GIS technology and mathematical meth- od. The results show that Both the amount of annual precipitation and annual rainstorm precipitation ap- peared slight decrease trend and their spatial patterns were much similar in the past 13 years. Significant fluctuations of rainstorm ratio could be found in the past 13 years. In the rainstorm concentration area, annual rainstorm precipitation shows more significant fluctuations than annual precipitation. Annual rain- storm frequency changes smoothly but with significant spatial difference. The imbalanced distribution of rainstorm in latitudinal direction is more obvious than that of longitudinal direction. Rainstorm showed tendency of moving to northeast in the past 13 years. The changing trends of the five variables show sig- nificant spatial differences and most areas appear increase or decrease but not significant trend.