恩施地区近54年降水量变化特征分析

基于湖北省恩施州的4个气象站点（巴东、绿葱坡、恩施、来凤）以及周边的3个站点（万州、奉节、五峰）近54 a逐年的降水量数据，利用气候倾向率法、ARCGIS空间分析法、小波周期分析法（Wavelet Analysis）和Mann Kendall突变分析法分别对研究区的降水量的时空变化、周期变化、突变进行了分析。研究表明：湖北恩施地区近54 a降水量呈现出波动式的下降趋势，20世纪90年代后尤为明显。从时间变化来看，70年代和90年代的降水量的下降量要比其它年代降水增加量要大；四季变化中除了冬季降水量呈现出较为明显的上升趋势外，其它3个季节降水量呈现较为明显的下降趋势。从空间变化来看，降水量最多的区域主要集中在绿葱坡地区，最少的区域主要集中在东北部的巴东和西北部利川的部分区域，形成了“一高两低”且有东北部向西部逐渐减少的分布态势

ANALYSIS OF THE PRECIPITATION CHANGE IN ENSHI SINCE RECENT 54 YEARS

Based on the four meteorological station(Badong,Lvcongpo,Enshi,Laifeng) and the surrounding three station(Wanzhou,Fengjie,Wufeng) nearly 54 years of precipitation data,using the climate trend rate analysis,ARCGIS of spatial analysis,Wavelet analysis and Mann-Kendall Mutation analysis,the temporal and spatial variation,periodic variation and mutation of precipitation were analyzed.The result showed that the precipitation in Enshi since recent 54 years appeared downtrend and the trend was much more obvious after 1990s.From the temporal change,the amount of precipitation decrease in 1970s and 1990s was more than the amount of precipitation increase in the other times.Precipitation in winter showed obviously increasing trend,while the precipitation in other three seasons showed decreasing trends.From the spatial change,the rainfall mainly focused on the Lvcongpo area,and the precipitation is the least in the northeast of Badong and the part area of northwest of Lichuan,forming "a top two low" and the trend of decreasing from northeast to west area.