长江下游地区汛期暴雨气候特征分析

根据2008-2013年我国暴雨统计结果, 分析了6 a间我国暴雨分布情况、变化趋势和演变规律, 结果表明:我国年降水量分布总体趋势由西北向东南依次递增, 西南地区东部、江汉地区、江淮地区、江南地区及华南地区是每年暴雨的多发区域, 华南南部(尤其是海南)为显著的暴雨多发区, 年暴雨日数常常超过10 d。我国每年平均暴雨日数为217.5 d, 以6-8月为最多; 平均每年出现39次主要暴雨过程次数, 其中8次由热带气旋登陆引起, 约有58%的主要暴雨过程出现在6-8月, 以7月最多; 每年平均出现特大暴雨26站次, 以华南居多, 年最大日降水量介于336.1~614.7 mm之间, 主要出现在6-10月之间。
每年遴选出的强度强、范围大、影响显著的10次重大暴雨事件均出现在5-11月, 其中以南方暴雨占多数。

The analysis of the distribution and trend for heavy rainfall based on the precipitation data from 2008 to 2013 in China

Based on the precipitation data from 2008 to 2013 in China, the characteristics of heavy rain including its distribution, variation and trend is investigated.The results show that the annual precipitation increases from northwest China to southeast China.Heavy rain usually happens in the east part of southwest China, Jianghan area, Jianghuai area, Jiangnan area and south China, especially the south part of south China, such as Hainan, where the annual heavy rain days are always beyond 10 d.The annual heay rain days in China are about 217.5 d, with most in June to August.Averagely, there are 39 heavy rain processes happened in China each year, and 8 of them are related with landing of tropic cyclone.Many heavy rain pocesses (about 58%) happen in June to August especially in July.
There are 26 extreme heavy rain events for each year in average, with most of them in south China.The maximum daily precipitation in each year is in a range of 336.1~614.7 mm, uaually happened in June to October.According to the intensity and area of rainfall and its damage, the 10 high impact heavy rain events are selected.These heavy rain events happen in May to November, and most of them happen in south China.