中文摘要：

采用1991~2010年小时降水数据对中国小时暴雨雨量和雨时进行研究。结果表明，在时间上，1991~2010年中国小时暴雨雨量和雨时的年累计值在波动中呈明显增加趋势。在空间上，小时暴雨雨量和雨时的高值区主要集中在中国黑龙江漠河-云南腾冲一线的东部地区，该界线以西则是低值地区，其中小时暴雨变化最为显著地区主要集中在中国东南沿海地区和西北内陆地区。中国白昼和夜晚的小时暴雨雨量和雨时在空间分布上也有类似的规律。在日变化的时间尺度上，小时暴雨雨量和雨时呈现出双峰现象，最高值均出现在17：00（北京时间，下同），而最低值出现在12：00。同时选择表征城镇化发展水平的夜晚灯光指数、黑炭气溶胶、低能见度日数和细颗粒物（PM2．5）浓度4个因子，分别与小时暴雨雨量和雨时做空间相关分析。在全国平均水平上，4个空间相关系数均在波动中呈明显增加趋势；而在中国气候变化区划一级分区上，空间相关系数均呈增加趋势，且增加趋势最为明显的是Ⅱ分区和Ⅲ分区。

英文摘要：

Daily precipitation data from observations cannot accurately reflect the spatiotemporal pattern of hourly heavy rainfall in China. Therefore, high temporal resolution precipitation data are desperately needed to advance the research in the field of hourly heavy rainfall in China. In this study, the diurnal cycle of hourly heavy rainfall amount （RA） and heavy rainfall hours （RF） are derived from hourly precipitation records during the period of 1991 to 2010 over entire China. Results show that both RA and RF exhibit obvious increasing trends despite several fluctuations during the period investigated. The area to the east （west） of the line linking Mohe in Heilongjiang and Tengchong in Yuunan is characterized by higher （lower） RA and RF. Changes in RA and RF are most notable in the coastal region of southeastern China and inland area of northwestern China. RA and RF in the nighttime and daytime also exhibit similar spatial distribution patterns. In terms of diurnal variation, RA and RF both show double peaks with the maximum values occurring at 1700 LST and the minimum values occurring at 1200 LST. In addition, four typical factors, i.e. the night light index, the black carbon aerosol optical depth, the number of days with low visibility, and PM2.5 concentration, which are used to represent the extent of urbanization, are analyzed in an attempt to figure out their relationship with RA and RF. The spatial correlation coefficients （CC） of RA and RF with the four factors all increased rapidly during the investigated period in this study over entire China. Specifically, sub-domains of Ⅱ and Ⅲ have more significant upward trends of CC according to the criteria of China Climate Zonation （Level 1）.