摘要
全球气候变化和快速城镇化双重影响下,城市洪涝问题日益突出,严重威胁区域的可持续发展。本文基于1960—2019年重庆市水文气象数据和第六次国际耦合模式比较计划(CMIP6)的10种全球气候模式,分析了重庆市极端降水、区域洪水的历史演变规律,构建了适用于重庆市的VIC-Cama Flood模型,并利用该模型对未来城市洪涝风险进行预估。主要结论如下:①重庆市1960—2019年极端降水量增多趋强,降水径流不均匀性上升;②VIC-Cama Flood模型在长江上游适用性较好,各子流域日径流过程模拟的平均纳什效率系数与相对误差绝对值分别为0.81、4.7%,水位模拟的平均纳什效率系数与相对误差绝对值分别为0.87、0.4%;③气候变化下重庆市未来极端降水大幅增加,不同情景下汛期超99%分位数年累积降水量较1985—2014年增加16.9%~85.9%;高排放情景下各站点年最大洪峰流量和年最大5日洪量的50年一遇值将缩短至20年一遇以下;④在不考虑水利工程调度影响下,未来气候变化将增加重庆市洪涝风险。极端降水-过境洪水-城市内涝的级联风险加剧将严重威胁城市防洪安全。
Urban flooding,exacerbated by the dual impacts of global climate change and rapid urbanization,poses a significant threat to the sustainable development of cities.Using hydrometeorological data from 1960 to 2019 in Chongqing and projections from ten global climate models from the Sixth Coupled Model Intercomparison Project(CMIP6),this study examines trends in extreme precipitation and regional flooding in the city.A large-scale VIC-Cama Flood coupled model was developed to simulate and forecast future climate,hydrology,and flood scenarios in Chongqing.The findings are as follows:①From 1960 to 2019,extreme precipitation in Chongqing showed an increasing trend,with growing variability in precipitation and discharge distribution.②The VIC-Cama Flood model,which is well-suited for the Upper Yangtze River,demonstrated good performance,with Nash efficiency coefficients of 0.81 for discharge simulations and 0.87 for water level simulations,and relative errors of 4.7%and 0.4%,respectively,across sub-basins.③Under future climate change scenarios,extreme precipitation in Chongqing is projected to increase significantly,with the annual cumulative precipitation exceeding the 99th percentile during the flood season increasing by 16.9%to 85.9%compared to the 1985—2014 period.Extreme hydrological events are expected to intensify,with the 50-year return period for maximum.discharge and five-day maximum flood volume potentially shortening to less than 20 years under high-emission scenarios.④In the absence of water conservation projects,future climate change will exacerbate the risk of urban flooding.The cascading effects of extreme precipitation,cross-boundary flooding,and urban waterlogging under climate change will pose serious challenges to urban planning and sustainable development in Chongqing.
作者
金君良
李文鑫
舒章康
张建云
许文涛
刘翠善
JIN Junliang;LI Wenxin;SHU Zhangkang;ZHANG Jianyun;XU Wentao;LIU Cuishan(The National Key Laboratory of Water Disaster Prevention,Nanjing 210098,China;Yangtze Institute for Conservation and Development,Nanjing 210098,China;Northwest Engineering Corporation Limited,Xi'an 710065,China;Research Center for Climate Change of Ministry of Water Resources,Nanjing 210029,China)
出处
《水科学进展》
EI
CAS
CSCD
北大核心
2024年第6期877-889,共13页
Advances in Water Science
基金
国家重点研发计划资助项目(2021YFC3200201)
国家自然科学基金资助项目(U2240203)。
