摘要
极端暴雨具有历时短、雨强大、破坏性强等特点,是引发城市内涝的主要原因之一,探究其时空动态分布规律,有助于提高城市内涝风险精细化管理水平.本文以北京市2004−2016年308个气象站点的降雨资料为研究样本,利用UMAP降维算法和HDBSCAN聚类算法,构建了各类极端暴雨事件的时空动态分布模型.首次提取了北京市全域4类极端暴雨模式:模式1,暴雨集中在主城区,并围绕主城区缓慢移动;模式2,暴雨从西南山区途经主城区,向东北方向移动;模式3,暴雨自西部山区向主城区西北部扩散,最后向主城区北部方向移动;模式4,暴雨从西部山区途经主城区向东移动.研究结果表明,北京市极端暴雨的主要类型为短历时降雨过程,暴雨中心在空间上均存在从西向东移动的趋势.其中,主城区、东南山区以及南部平原地区面临相对更高的极端暴雨风险.各类极端暴雨的模式特征物理机制明确,其重构特征可以充分表征实际暴雨事件特性.研究成果可为北京市降雨设计、城市内涝风险管理等工作提供一定的参考.
Extreme rainstorm is characterized by short duration,strong downpours and widespread destructionall major causes of flash flood and waterlogging disasters.Exploring spatiotemporal dynamics of extreme rainstorm is helpful to refined management level of urban waterlogging risk.A method of clustering combined with dimensionality reduction algorithm was proposed in this study,to extract spatiotemporal dynamics of extreme rainstorm events.Precipitation data from 308 meteorological stations in Beijing from 2004 to 2016 were used,to construct spatiotemporal dynamics models of various extreme rainstorm events with the HDBSCAN clustering method.This was combined with UMAP dimensionality reduction algorithm to extract 4 types of extreme rainstorm models in Beijing.In mode 1,rainstorm was found concentrated in the main urban area,moving slowly around.In mode 2,rainstorm was found to move from the southwest mountainous area through the main urban area to the northeast.In mode 3,the rainstorm was found to spread from the western mountainous area to the northwest of the city,and to finally move to the north of the city.In mode 4,torrential rain was found to move westward from western mountain area to urban area.These results show that the main type of extreme rainstorm in Beijing is short-duration precipitation,and the rainstorm center has the tendency to move from west to east.Downtown area,southeastern mountainous area and southern plain area all face relatively higher extreme precipitation risks.The physical mechanism of model characteristics of all kinds of extreme rainfall is clear,and the reconstruction characteristics of rainfall events could fully represent actual rainfall events.This study provides important basis for flood forecasting and scientific management in Beijing.
作者
徐淑高
王纤阳
蒋卫威
鱼京善
刘源
周桂欢
XU Shugao;WANG Xianyang;JIANG Weiwei;YU Jingshan;LIU Yuan;ZHOU Guihuan(Digital Watershed Laboratory,College of Water Science,Beijing Normal University,100875,Beijing,China;State Key Laboratory of Environment Geochemistry,Institute of Geochemistry,Chinese Academy of Sciences,550081,Guiyang,Guizhou,China;China Institute of Water Resource and Hydropower Research,100038,Beijing,China)
出处
《北京师范大学学报(自然科学版)》
CAS
CSCD
北大核心
2023年第2期269-279,共11页
Journal of Beijing Normal University(Natural Science)
基金
国家自然科学基金重点资助项目(52239003)
济南市水务科技资助项目(JNSWKJ202001)。