Department of Civil and Environmental Engineering, West Virginia University, 395 Evansdale Drive, Morgantown, WV 26506-6103, USA.
Department of Civil and Environmental Engineering, West Virginia University, 395 Evansdale Drive, Morgantown, WV 26506-6103, USA.
Sci Total Environ. 2021 Jul 15;778:146017. doi: 10.1016/j.scitotenv.2021.146017. Epub 2021 Feb 23.
This study aims to evaluate the individual and synergistic controls of climatic and land cover changes on stormwater runoff regimes, and perform a comparative synthesis of the historical and future runoffs for complex coastal-urban environments. A large-scale (7117 km) mechanistic hydrologic model was developed for Florida Southeast Coasts Basin as the study area using U.S. Environmental Protection Agency (EPA)'s Storm Water Management Model 5.1. The model was calibrated and validated with daily streamflow observations (Nash-Sutcliffe Efficiency = 0.74 to 0.92) during 2004-2013 (termed 2010s), computing the corresponding runoff volume as a historical reference. Runoffs for 2050s (2044-2053) and 2080s (2076-2085) were quantified by incorporating climatic projections from 20 General Circulation Models and land cover projections from EPA under the Representative Concentration Pathways (RCP) 4.5 and 8.5 scenarios. We found a predominant climatic control on the potential runoff changes and a high vulnerability in the coastal-urban environments. The concurrent changes in climate and land cover led to synergistic (stronger than the sum of individual effects) nonlinear responses of runoff. The projected changes in climate and land cover together would increase the annual basin runoff volume by 118%, 106%, 86%, and 80% under the 2080s-RCP 4.5, 2050s-RCP 4.5, 2050s-RCP 8.5, and 2080s-RCP 8.5 scenarios, respectively. Greater increases in runoff were noted at and around the urban centers than that at the non-urban areas across the basin. The relative increases in runoff were higher during the dry season and transitional months (October-May) than the wet season (June-September). Our findings would guide stormwater management and ecosystem protection for southeast Florida and coastal built environments across the world.
本研究旨在评估气候和土地覆盖变化对城市暴雨径流的个体和协同控制，并对复杂沿海城市环境的历史和未来径流进行综合比较。该研究以美国佛罗里达州东南海岸流域为研究区域，采用美国环保署（EPA）的 Storm Water Management Model 5.1 开发了一个大规模（7117 公里）的机制水文模型。该模型利用 2004-2013 年（称为 2010 年代）的每日流量观测值（纳什-苏特克里夫效率为 0.74 至 0.92）进行了校准和验证，计算了相应的径流量作为历史参考。利用来自 20 个通用环流模型的气候预测和 EPA 在美国代表浓度路径（RCP）4.5 和 8.5 情景下的土地覆盖预测，量化了 2050 年代（2044-2053 年）和 2080 年代（2076-2085 年）的径流量。研究发现，气候对潜在径流变化具有主要控制作用，而沿海城市环境则非常脆弱。气候和土地覆盖的同时变化导致径流的协同（比个体效应的总和更强）非线性响应。在 RCP 4.5 下的 2080 年代、2050 年代-RCP 4.5、2050 年代-RCP 8.5 和 2080 年代-RCP 8.5 情景下，预计气候和土地覆盖的变化将使流域年径流量分别增加 118%、106%、86%和 80%。与流域的非城市地区相比，城市中心及其周边地区的径流量增加幅度更大。在旱季和过渡月份（10 月至 5 月），径流的相对增加幅度高于雨季（6 月至 9 月）。本研究结果将为美国佛罗里达州东南部和世界各地的沿海城市环境的雨水管理和生态系统保护提供指导。
