基于EOF和REOF分析江淮梅雨量的时空分布

Temporal and Spatial Distribution of Jianghuai Meiyu with EOF and REOF Analysis

基于江淮梅雨区域50个气象台站1960-2002年的梅雨量资料,利用EOF、REOF展开方法,分析了江淮梅雨降水的空间分布及时间演变特征.EOF展开方法表明江淮梅雨前三个特征向量累积方差贡献比例为88.9%,其主要特征是三个特征向量场呈现纬向带状分布;第一特征向量场空间分布均为正值,说明江淮梅雨量的干湿变化具有一致性,但是各特征向量场之间的特点相差明显.REOF展开方法表明可以把江淮梅雨划分为6个典型的梅雨量场;后一个时间系数序列的变化幅度比前一个时间序列要小;主成分旋转后载荷要比旋转前分布均匀得多;第一时间系数的变化等同于各站平均梅雨量变化.

Based on the data of Meiyu precipitation about 50 weather stations from 1960 to 2002, temporal and spatial distribution characteristics are analyzed with EOF and REOF methods. EOF analysis shows that the ratio of the front 3 eigenvectors with total square error is 88.9 % , and the front 3 eigenvector fields present string distribution, The characteristic of each eigenvector field is different. REOF analysis manifests that Meiyu precipitation fields may be divided into 6 types and the change of rotated eigenvec＇tor field is little. The change of the first temporal coefficient is analogous with the change of average Meiyu precipitation on all stations.