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投稿时间：2017-11-27 修订日期：2019-03-04
投稿时间：2017-11-27 修订日期：2019-03-04
中文摘要: 利用1960—2014年兰州、临夏、合作、定西、武都、天水、平凉和西峰逐分钟降水资料，分析甘肃河东强降水频次的时空分布特征，建立基于Copula函数的持续时间和过程雨量的联合分布，基于该函数开展强降水发生概率分析研究。结果表明：（1）甘肃河东近55年来平均强降水频次为1.64次/(a?站)，主要特征为持续时间短、过程雨量小，平均持续时间为2.88 h，过程雨量为23.4 mm，持续时间小于1 h的概率高达13.4%；（2）强降水主要发生在汛期(4—9月)，月变化服从正态分布，墨西哥帽小波分析表明频次存在着显著的22~23 a和13~15 a的年代际和3~7 a的年际变化；（3）强降水发生概率从大到小依次为平凉、西峰、天水、定西、武都、临夏、兰州和合作，相应的陇东最大，陇南次之，中部地区最小。
中文关键词: Copula函数，强降水，发生概率，甘肃河东
Abstract:Based on minutely precipitation collected from Lanzhou, Linxia, Hezuo, Dingxi, Wudu, Tianshui, Pingliang and Xifeng weather stations in Hedong Area of Gansu Province during 1960-2014, the spatio temporal distribution characteristics of heavy rainfall frequencies are analyzed. Besides, the risk analysis on duration and accumulated precipitation is obtained by Copula function based 〖JP2〗on a bivariate Copu 〖JP〗la distribution model for heavy rainfall variables. The results show that: (1) The main characteristics of heavy rainfall in Hedong Area during recent 55 years are short duration and low accumulated precipitation. The occurring frequency is 1.64 time/(a?station), average duration is 2.88 h, average accumulated precipitation is about 23.4 mm and the probability of duration less than 1 h is up to 13.4%. (2) Heavy rainfall occurs mainly from April to September, and the monthly variation is in the normal distribution. The Mexico Hat wavelet analysis shows that there are obviously interdecadal changes of 22-23 years and 13-15 years, and interannual changes 3-7 years in the heavy rainfall. (3) The frequency of heavy rainfall from large to small is Pingliang, Xifeng, Tianshui, Dingxi, Wudu, Linxia, Lanzhou and Hezuo in order. Correspondingly, the maximum frequency occurrs in eastern Gansu, second in southern Gansu, and the smallest central Gansu.
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基金项目:国家自然科学基金重点项目(41630426)和国家重点基础研究发展计划（973计划）(2013CB430206)共同资助
引用文本：
杨银,李岩瑛,陈豫英,陈自艳,刘蓉,2019.基于Copula函数的甘肃河东短时强降水特征分析[J].气象,45(5):632-640.
YANG Yin,LI Yanying,CHEN Yuying,CHEN Ziyan,LIU Rong,2019.Characteristics of Short Time Heavy Rainfall in Hedong Area of Gansu Based on Copula Function[J].Meteor Mon,45(5):632-640.
杨银,李岩瑛,陈豫英,陈自艳,刘蓉,2019.基于Copula函数的甘肃河东短时强降水特征分析[J].气象,45(5):632-640.
YANG Yin,LI Yanying,CHEN Yuying,CHEN Ziyan,LIU Rong,2019.Characteristics of Short Time Heavy Rainfall in Hedong Area of Gansu Based on Copula Function[J].Meteor Mon,45(5):632-640.
