长江上游极端降水非平稳拟合及致灾效应分析  

Non-stationary fitting of extreme precipitation in the upper reaches of the Yangtze River and analysis of its disaster causing effects

作　　者：高斌 GAO Bin(State Key Laboratory of Intelligent Geotechnics and Tunnelling,Xi’an 710043,Shaanxi,China;China Railway First Survey and Design Institute Group Co.,Ltd.,Xi’an 710043,Shaanxi,China)

机构地区：[1]极端环境岩土和隧道工程智能建养全国重点实验室,陕西西安710043 [2]中铁第一勘察设计院集团有限公司,陕西西安710043

出　　处：《水利水电技术(中英文)》2025年第2期1-14,共14页Water Resources and Hydropower Engineering

基　　金：中铁第一勘察设计院集团有限公司科研项目(KY23-B035);中国国家铁路集团有限公司重大项目(P2021G047);国家自然科学基金项目(51779271)。

摘　　要：【目的】近年来,变化环境下出现的极端降水事件日益频繁,传统频率分析中的平稳性假设逐渐受到质疑。因此需要对流域极端降水的非平稳特征进行合理分析,有助于动态评估暴雨风险、提升流域防灾减灾能力。【方法】基于GAMLSS模型对长江上游流域82个气象站点的极端降水频率指数和强度指数,建立了以时间为解释变量的时变分布模型,然后采用Mann-kendall法分析了极端降水频率指数和强度指数序列的变化趋势,对长江上游流域的极端降水致灾效应进行了评价。【结果】结果表明:(1)长江上游流域多数站点的极端降水指数呈现非平稳性特征。其中,中雨日数R10、总降雨量PRCPTOT具有非平稳特征的站点达到了70%以上,大雨日数R25、强降水量R95P、极端日降水量RX1day具有非平稳特征的站点达到了40%以上,极强降水量R99p具有非平稳特征的站点约占13%;(2)GAMLSS最佳模型中极端降水频率、强度指数的分布参数序列呈显著增加趋势的站点比例分别为20/82、36/82。【结论】宜宾至宜昌段的中上游地区极端降水的频率在未来会增大;长江上游的中部地区极端降水的强度在未来会增大;金沙江石鼓以下和岷沱江流域的中下游交界地区极端降水的频率和强度在未来均会增大。相对于简单的趋势分析,时变分布模型可以更加详细地诊断序列的非一致性特征。[Objective]In recent years,extreme precipitation events occurring in changing environments have become increasingly frequent,and the assumption of stationary in traditional frequency analysis has been gradually questioned.Therefore,it is necessary to reasonably analyze the non-stationary characteristics of extreme precipitation in the basin,which will help to dynamically assess the risk of rainstorm and improve the disaster prevention and mitigation capacity of the basin.[Methods]Based on the GAMLSS model,a time-varying distribution model with time as the explanatory variable is established for the extreme precipitation frequency index and intensity index of 82 meteorological stations in the upper reaches of the Yangtze River Basin.Then,the Mann Kendall method is used to analyze the trend of the extreme precipitation frequency index and intensity index series,and the disaster causing effect of extreme precipitation in the upper reaches of the Yangtze River Basin is evaluated.[Results]The result indicate that:(1)the extreme precipitation index of most stations in the upper reaches of the Yangtze River basin exhibits non-stationary characteristics.Among them,more than 70%of stations have non-stationary characteristics for moderate rain days R10 and total rainfall PRCPTOT,over 40%have non-stationary characteristics for heavy rain days R25,heavy rainfall R95P,and extreme daily rainfall RX1day,and about 13%have non-stationary characteristics for extremely heavy rainfall R99p;(2)The proportion of stations with significantly increasing distribution parameter sequences of extreme precipitation frequency and intensity index in the GAMLSS optimal model is 20/82 and 36/82,respectively.[Conclusion]The frequency of extreme precipitation in the middle and upper reaches of the Yibin to Yichang section will increase in the future;the intensity of extreme precipitation in the central region of the upper reaches of the Yangtze River will increase in the future;the frequency and intensity of extreme precipitation in the border area

关 键 词：长江上游 极端降水指数 非平稳 致灾效应 洪水 时空变化 降雨 气候变化 

分 类 号：TV213.4[水利工程—水文学及水资源]