中文摘要：

根据华东地区1961－2010年逐日降水量台站观测资料，利用趋势分析、Mann—Kendall检验和经验正交函数（EOF）分析等方法揭示不同强度降水日数的时空演变特征。结果表明，华东地区的小雨日数为总雨日数的72．42％，占总雨日数的最大比重。同时发现小雨目数和总雨日数（暴雨和大暴雨日数）表现为显著的减少（增加）趋势，说明总雨日数的减少主要是由于小雨日数的减少所致。EOF分析结果显示总雨日和小雨日的主要EOF模态在空间上表现出全场一致的减少趋势以及南北反相位的特征。福建中部既是总雨日数和小雨日数最大的区域，也是两者减少趋势最明显的地区。暴雨日数和大暴雨日数高值中心出现的区域基本重合，大致在浙江－江西－安徽三省交界处。

英文摘要：

The spatial and temporal distributions of rainy days with different precipitation intensities over East China were revealed using trend analysis, Maim-Kendall test, and EOF （Empirical Orthogonal Function） analysis methods on observed daily precipitation data for East China between 1961 and 2010. The results show that light precipitation rainy days made up 72.42% of the total number of rainy days, which was more than the other three precipitation grades. It was also evident that the number of light precipitation rainy days decreased and the total number of torrential and heavy precipitation days increased significantly over the study period. The EOF analysis results indicated that the two dominant EOF modes, number of light precipitation rainy days and total number of rainy days, decreased over the whole of East China and had opposite phases in northern and southern East China. The areas with the highest total numbers of rainy days and light precipitation days were in the middle of Fujian Province, where both parameters decreased the most. However, the areas with the highest numbers of torrential rain and heavy rain days were Zhejiang, Jiangxi, and Anhui provinces.