基于Vine Copula的强风暴雨复合型风险分析

Composite Risk Analysis of Strong Wind and Rainstorm Based on Vine Copula

构建基于D-Vine Copula函数的强风暴雨复合型分布模型,利用北京市十三陵水库流域的实测数据进行敏感性分析及风险评估。结果表明:联合分布对降水量、降水强度、风速和温度4个研究因子的敏感性具有差异性。基于敏感性分析结果,随着降水强度和风速的概率分布值增大,联合概率分布增大,同现概率分布减小,最大联合风险率为24.5%;随着降水强度和降水量的概率分布值增大,联合概率分布增大,同现概率分布减小,最大联合风险率为18.1%;Vine Copula可较好地反映出水文气象因子间的相关关系,降水强度和风速、降水量和降水强度的概率分布值及组合风险率均对联合分布呈现正相关关系,发生气象灾害时易出现联合响应。该研究为强风暴雨复合型风险的调控等提供了理论与方法支撑。

The composite distribution model of strong wind and rainstorm based on D-Vine Copula function was constructed in this study,and the measured data of Beijing Ming Tombs Reservoir were used for sensitive analysis and risk assessment.The re-sults show that the sensitivities of the joint distribution to precipitation,precipitation intensity,wind speed and temperature were different.Based on the results of sensitivity analysis,the value of joint distribution increased and the occurrence distribution de-creased with the increase of the probability distribution of precipitation intensity and wind speed,and the maximum joint risk rate was 24.5%.With the increase of the probability distribution of precipitation intensity and precipitation,the joint distribution in-creased and the occurrence distribution decreased,and the maximum joint risk rate was 18.1%.Vine Copula could reflect the cor-relation among hydro-meteorological factors.The probability distribution and combined risk rates of precipitation intensity and wind speed,as well as those of precipitation and intensity,showed positive correlations with the joint distribution when meteoro-logical disasters occurred.This study could provide theoretical and methodological support for the control of the combined risk of strong wind and heavy rain.