陕西省降水时空分布与变化特征分析

Analysis on Spatial and Temporal Distribution of Precipitation Variation in Shaanxi Province

基于陕西省1961—2005年97个县市的逐月降水资料采用经验正交函数分析(EOF)方法对降水空间分布进行研究;利用降水集度法表示降水的年内分异情况;并通过求各降水量场时间系数的变化趋势系数探讨降水时间变化特征。结果表明,全省降水呈南多北少的特点,主要有4种雨型,大部分地区降水呈季节性变化,降水量整体缓慢下降,季节上变化为春、秋下降,夏、冬上升。

Based on monthly precipitation data of 97 cities and counties from 1961-2005 in Shanxi Province,the rainfall spatial distribution of Shaanxi Province is studied with EOF(Empirical orthogonal function) method.The article takes the precipitation set degree to describe precipitation differentiation during the whole year this area.And it explores the time variation of rainfall by seeking the precipitation field time trend coefficient.The results show that the rainfall in the southern part of Shaanxi Province is more than it in the northern part.It has four kinds of rain type,the precipitation was seasonal changes in most areas,the precipitation overall slow decline,and the seasonal changes is that spring,autumn decline and summer,winter rose.