中文摘要：

选取青藏高原东北侧临夏回族自治州的6个代表气象站点自建站以来的强降水（日降水量≥25．0mm）资料，对该地区强降水的时空分布及气候变化特征进行了分析；利用Pearson—Ⅲ概率分布方法对强降水异常气候重现期进行了计算。结果显示，自20世纪80年代以来，该区域强降水日数呈显著增多趋势；对2008年8月20日一次强降水过程进行的重现期计算显示，与人工估算结果相符。

英文摘要：

The heavy precipitation was analyzed based on the data from 1943 to 2008 in 6 representative meteorological stations in Linxia which is located in the northeast side of Qinghai - Tibet Plateau. At first, the spatial and temporal distribution of heavy precipitation in this region was analyzed, and then, the return periods of heavy precipitation was assessed by Pearson - III distribution method. Resuits show that the days of heavy precipitation increased conspicuously since the 1980s. The return period was calculated about a heavy precipitation event in this region occurred on August 20, 2008 , and the result accorded with the artificial - assessment.