华北春季干湿状况的时空分布

The temporal-spatial distributions of the dry/wet conditons over North China

Here the water abnormal index given by Palmer is used to calculate Palmer index in spring over North China, which is considered as a comprehensive index of the dry and humidity conditions in spring over the regions. The method of the empirical orthogonal function was used to analyse the character of temporal-spatial distributions of the dry and humidity condition in spring, and its stability was discussed, too. It is thought that the, spatial distribution characters of the first 4 items and their. temporal evolution laws are very steady.