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利用中国２９６个分布均匀的测站的逐日降水资料，研究了中国过去４５ａ中降水量、降水频率、降水强度等方面的极值变化趋势。结果表明，总体上讲，中国年降水量、１日和３日最大降水量以及不同级别的强降水总量没有发现明显的极端化倾向，但伴随着降水日数极端偏多的区域范围越来越小的变化趋势，平均降水强度极端偏高的区域范围表现为扩大的趋势。中国降水极值变化还反映出明显的区域性特点。在中国东部，平均降水强度极值出现的范围趋于扩大。如华北地区在年降水量明显趋于减少的同时，年降水量极端偏多的范围减少，１日和３日最大降水量、日降水≥５０ｍｍ和１００ｍｍ的暴雨日数极端偏多的情况也趋于减少，而平均降水强度极值显著增加。在年降水明显趋于增多的西北西部地区，降水日数的极值变化趋势不明显，但年降水量、１日和３日最大降水量以及日降水≥１０ｍｍ的降水总量极端偏多的区域范围均反映出趋于增加的变化趋势。
Based on the daily precipitation data of 296 well-distributed stations in China, the extreme value trends of precipitation, precipitation frequency and precipitation intensity in China over the past 45 years were studied. The results show that, on the whole, there is no obvious extreme tendency of annual precipitation, maximum precipitation on the 1st and 3rd, and the total amount of heavy precipitation in different levels, but more and more areas accompanied by extreme precipitation days The trend of small change and the region with extremely high average precipitation intensity show an expanding trend. The extreme changes in precipitation in China also reflect the obvious regional characteristics. In eastern China, the range of extreme precipitation anomalies tends to widen. For example, in North China, the annual precipitation is obviously decreasing while the range of extreme annual precipitation is decreasing. The cases of extreme precipitation on day 1 and day 3, extreme rainy days with daily precipitation ≥50 mm and 100 mm also tend to be more Decreases, while the mean precipitation intensity increases significantly. In the northwestern and western regions where the annual precipitation is obviously increasing, the extreme trend of the precipitation days is not obvious, but the annual precipitation, the maximum precipitation on the 1st and 3rd and the extreme precipitation on the daily precipitation≥10mm All reflect the tendency of increasing trend.