陕甘宁及内蒙古西部地区春季降水的气候特征

Climate characteristics of spring precipitation in the eastern part of northwest China and western Inner Mongolia

利用陕西、甘肃、宁夏和内蒙古西部地区64个测站1961～2000年春季降水量的资料,采用EOF、REOF、小波分析和突变分析等方法,对陕甘宁及内蒙古西部地区春季降水的空间分布特征和时间演变规律进行了诊断分析研究.结果表明:陕甘宁及内蒙古西部地区春季降水的空间分布既有整体一致的特性,也存在东部和西部、南部和北部相反变化的差异,可将陕甘宁及内蒙古西部地区划分为三个主要的降水异常区域:陕南秦岭区、甘蒙西部区和河套区.各异常区代表站资料反映出近40a来陕甘宁及内蒙古西部地区春季降水呈减少趋势,但未发生突变现象,并且存在着14a,8a和2～6a的周期变化.

Used 1961～2000 years spring precipitation data over 64 stations of the eastern part of northwest China and western Inner Mongolia region,the temporal and spatial variability characteristics were studied by applying the methods of EOF,REOF and wavelet analysis.The results showed that the spring precipitation distribution exhibits the common characteristics as well as the spatial differences,which can be classified into three types as Qinling,West and Hetao.There exists droughty trend over the eastern part of...