华北地区冬季降水时空分布特征分析

Characteristics Analysis of Winter Precipitation in North China

利用华北地区29个测站,57年冬季降水量资料,采用EOF,REOF,小波分析等方法,对华北地区冬季降水量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:华北地区冬季降水的空间分布在整体一致的基础上,即存在南北分布差异,又有着环渤海湾地区与其它地区的差异;冬季整个华北地区可以划分为五个主要的降水异常区:黄河中下游区、京津唐区、呼伦贝尔盟区、黄河河套区、冀北山地区;整个华北在70年代末期有明显的降水减少趋势;各区域冬季降水有不同尺度的年际和年代际周期变化,但基本上都存在着准12～14年、准3～5年的周期振荡。

With the winter（Dec-Feb） precipitation data over 29 stations in the North China from 1951 to 2008,the temporal and spatial variability characteristics were studied by using the methods of EOF,REOF,wavelet analysis and etc.The results indicate that the winter precipitation distribution exhibits the common features as well as the spatial differences,which can be divided into five areas.There exists dryer trend in winter of the North China in the last 57 years.Generally,winter precipitation presents downward tendency and the periods of 12-14a and 3-5a.