基于蒙特卡罗方法的山洪概率预警研究  

Probabilistic Warning for Flsh Flood Based on Monte Carlo Method

作　　者：吴雪梅 辉尚强 赵雨婷 覃光华[1,2] 李红霞[1,2] WU Xuemei;HUI Shangqiang;ZHAO Yuting;QIN Guanghua;LI Hongxia(College of Water Resource&Hydropower,Sichuan University,Chengdu 610065,China;State Key Laboratory of Hydraulics and Mountain River Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学水利水电学院,四川成都610065 [2]四川大学山区河流保护与治理全国重点实验室,四川成都610065

出　　处：《水文》2025年第2期88-93,共6页Journal of China Hydrology

基　　金：国家重点研发计划项目(2019YFC1510703);国家自然科学基金面上项目(51979177)。

摘　　要：及时准确的山洪预警对降低山洪灾害影响至关重要。目前常用的山洪预警方法为临界雨量法,属于确定性预警方法。然而,由于山洪的复杂性和不确定性,确定性方法在实际应用中存在一定的局限性。基于水文模型参数不确定性分析,构建山洪灾害概率预警模型。首先基于蒙特卡罗法对新安江模型进行参数不确定性分析,然后对所选参数组进行各个历时情景下的临界雨量指标计算,并结合概率密度分析确定致灾概率。以四川省清溪河流域山洪预警为例,研究结果表明,相比于确定性方法,概率预警方法的空报场次由28场显著减少至16场,关键成功指数PCSI由0.41提高到0.54,说明提出的山洪概率预警方法具有较高的准确性和可靠性,可以较好地应用于山洪预警。Timely and accurate flash flood early warning is crucial for reducing the impact of flash floods.Currently,the commonly used flash flood warning approach is the rainfall threshold approach,which belongs to the deterministic early warning approach.However,due to the complexity and uncertainty of flash floods,the deterministic approach has some limitations in practical application.Based on the parameter uncertainty of hydrological model,a probabilistic warning model for flash floods was proposed.First,the Monte Carlo method was applied to the Xinanjiang model to analyze the parameter uncertainty,and then the rainfall threshold was calculated for each time span for the selected parameter sets,and the probability of exceedance was determined by combining with the probability density analysis.Taking the flash flood warning in Qingxi River catchment of Sichuan Province as an example,the results show that compared with the deterministic approach,the number of false alarms is significantly reduced from 28 to 16,and the critical success index(PCSI)is improved from 0.41 to 0.54,which indicates that the probabilistic warning approach has a high accuracy and reliability,and it can be better applied for flash flood warning.

关 键 词：山洪灾害 临界雨量 参数不确定性 概率预警 

分 类 号：P338[天文地球—水文科学] TV87[水利工程—水文学及水资源] X43[天文地球—地球物理学]