北京降雨过程分型特征及短历时降雨重现期研究  

Characteristics of temporal pattern and return period of short-duration rainfall at Beijing Observatory

作　　者：王彬雁 赵琳娜[1,2] 巩远发[1] 白雪梅[1,2] 

机构地区：[1]成都信息工程大学大气科学学院高原大气与环境四川省重点实验室,成都610225 [2]中国气象科学研究院灾害天气国家重点实验室,北京100081

出　　处：《暴雨灾害》2015年第4期302-308,共7页Torrential Rain and Disasters

基　　金：国家重点基础研究发展计划(2015CB452806);国家自然科学基金项目(41475044;91437104;91224004);国家水体污染控制与治理重大专项(2013ZX07304-001-1)

摘　　要：利用北京观象台1961—2004年44 a逐分钟自记降雨资料,采用模糊识别法和统计分析法对北京市降雨过程进行雨型分型,并对5、10、15、20、30、45、60、90、120、180 min共10种不同短历时年最大降雨极值的概率分布利用指数分布、耿贝尔分布和皮尔逊Ⅲ型概率分布函数进行拟合。在此基础上,推算各历时降雨重现期极值。结果表明,暴雨天数年代际差异较大,暴雨量主要集中在50~100 mm范围内;不同月份雨型分布不一致,6月多双峰型,7—9月多单峰型雨型;总体上,北京降雨过程多为单峰型,占80%以上。最大降雨量主要出现在午后至傍晚和凌晨;北京短历时降雨极值的概率分布多数不服从指数分布而服从皮尔逊Ⅲ型分布;重现期降雨极值随历时增加而增大,2 a至100 a重现期内10 min降雨极值取值为10.4~22.6 mm,60 min降雨极值取值为22.3~59.2 mm,180 min取值为53.0~89.8 mm。Using the rainfall autographic records with 1-minute interval at Beijing Observatory from 1961 to 2004, we have performed the classification of short-duration rainfall pattern with fuzzy identification method and statistical analysis method. The Exponential distribution,Gumbel distribution and Pearson-Ⅲ distribution are also fitted to infer the short-duration rainfall extremes, such as 5-min, 10-min,15-min, 20-min, 30-min, 45-min, 60-min, 90-min, 120-min and 180-min extremes, based on the establishment of the probability distribution pattern under different return period scenarios, respectively. Results indicate that the amounts of rainfall mainly concentrate on 50-100 mm, but inter-decadal variations of torrential rain days are evident. The monthly temporal patterns are different so that the bimodal type is dominant in June while the unimodal type is mainly temporal pattern from July to September. The dominant temporal patterns of the short-duration rainfall process at Beijing Observatory are unimodal type, which account for more than 80% of all short-duration rainfall process. The maximum precipitation occurs in the two periods from afternoon to evening and before dawn. Pearson-Ⅲ distribution is an adequate fit to the probability distribution of the short-period precipitation probability at Beijing Observatory according to the comparison among the fittings of Exponential distribution, Gumbel distribution and Pearson-Ⅲ distribution. The maximum amount of precipitation under different return period increases with return period. That is the rainfall amounts of 10-min, 60-min and 180-min from 2 years to 100 years return period are limited in 10.4-22.6 mm, 22.3-59.2 mm and 53.0-89.8 mm, respectively. All these results will provide a more scientific support to prevent urban waterlogging deposition and drainage system planning.

关 键 词：暴雨雨型 降雨过程 重现期 皮尔逊Ⅲ型 

分 类 号：P468.024[天文地球—大气科学及气象学]