四川省近10年极端小时降水时空分布特征

利用2012~2020年四川省156个国家气象观测站小时降水资料，以四川盆地、川西高原和攀西地区为考察重点，统计分析了全省极端小时降水的时空分布特征。结果表明:（1）四川省各站极端小时降水阈值、发生频次、平均强度及贡献率差异明显，高值区主要集中在盆地和攀西南部；盆地多站极端小时降水阈值在50 mm/h以上，小时降水极大值超过80 mm/h。（2）四川省极端小时降水事件主要集中在7月和8月，其中50 mm以上的小时强降水事件占比超过1/3；盆地、川西高原和攀西地区极端小时降水发生频次分别在7月、6月和8月达到最高，而小时强降水事件分别在8月、7月和6月出现最多。（3）四川省极端小时降水频次日变化峰值出现在02时，具有单峰和夜发特征，其中盆地、川西高原和攀西地区主峰值分别出现在05时、21时和02时；四川省50 mm以上小时强降水事件夜发占比达63.5%，各区域出现高峰时段差异大。 

Temporal and Spatial Distribution Characteristics of Extreme Hourly Precipitation in Sichuan Province in Recent 10 Years

Based on the hourly precipitation data of 156 national meteorological stations in Sichuan province from 2012 to 2020, the temporal and spatial distribution characteristics of extreme hourly precipitation in Sichuan province and western Sichuan Plateau, Panxi Region and Sichuan Basin are analyzed. The results showed that: (1) There were obvious differences in extreme hourly precipitation threshold, occurrence frequency, average intensity and contribution rate among stations in Sichuan Province. The high value areas were mainly concentrated in the Basin and the south of Panxi Region. The extreme precipitation threshold was more than 50 mm/h in many parts of the Sichuan Basin, and the maximum was up to more than 80 mm/h in some stations. (2) Extreme hourly precipitation events mainly occurred in July and August, and among them, the events above 50 mm/h accounted for more than 1/3. The highest frequency of extreme hourly precipitation in Sichuan Basin, western Sichuan Plateau and Panxi Region reached the highest in July, June and August respectively, while the extreme hourly precipitation events occurred most in August, July and June respectively. (3) The extreme hourly precipitation frequency of Sichuan had the characteristics of single peak diurnal variation and mainly occurred nighttime and the main peak appeared at 02:00. The peak time in Sichuan Basin, western Sichuan Plateau and Panxi Region occurred at 05:00, 21:00 and 02:00 respectively. The number of extreme hourly precipitation events of more than 50 mm at night in the province accounted for 63.5%, and there were great differences in peak periods in various regions.