基于Copula函数的东江博罗站年最大洪水联合分布研究

以东江博罗站1953—2013年长系列年最大洪峰流量及其峰现时间为基础,采用Von Mises函数拟合年最大洪水洪峰出现时间的分布特征,皮尔逊III型函数拟合年最大洪水洪峰流量的分布特征,采用Frank Copula函数构建了洪峰流量和峰现时间两变量的联合分布,分析了东江博罗站洪峰出现时间分布特性,年最大洪水事件联合重现期和条件重现期。结果表明:以Von Mises,皮尔逊III型及Frank Copula函数构建的联合分布函数均能较好拟合东江博罗站年最大洪水分布特征,可有效挖掘流域洪水信息,为流域防洪规划和风险管理提供参考。

Analysis on Annual Maximum Flood Joint Distribution at Dongjiang Boluo Station using Copula Function

Von Mises and Pearson Type III distribution are used to describe the occurrence dates and magnitudes of annual maximum flood respectively. A bivariate joint distribution with Von Mises and Pearson Type III distribution margins is developed based on the Frank Copula from the data of annual maximum flood occurrence dates and magnitudes frequency at Boluo hydrologic station from 1953 to 2013.Copula Function are used to describe the annual maximum flood Characteristics, conditional probability,joint probability and bivariate return period. A case study suggests that the Von Mises distribution, Pearson Type III distribution and the bivariate joint distribution base on Frank Copula can fit both occurrence dates and magnitudes of annual maximum flood series well. More information of flood can be mined, and it is provided as a reference for flood control planning and risk management in Dongjiang river basin.