Abstract：The impacts of underlying urban surfaces on rainfall are due to the specific dynamics and thermodynamics properties of urban areas. The weather research and forecasting model (WRF) was used in this study to simulate the heavy rainfall event on July 20, 2016 in the Xiongan New Area as an example. Different urban canopy roughness scenarios were created to study the effects of the urban canopy roughness on the storm evolution and rainfall area. The results show that the urban canopy roughness significantly impacts the storm evolution and rainfall area. When the urban canopy is not very rough, the air is heated as it passes through the urban area, resulting in water vapor convergence and rain island effects which increase the rainfall over the urban area and the downwind region. When the urban canopy is rough, the storm elements move slowly with more rainfall upwind. Increases in the urban canopy roughness may change the direction of the storm movement and increase the rainfall outside the city. This study assesses the impacts of urban canopy roughness on rainfall and provides a scientific basis for future urban planning and construction. In addition, the simulation results have reference significance for the selection of urban rainfall simulation parameters.
邢月, 刘家辉, 倪广恒. 城市冠层粗糙度对暴雨云团运动和降雨落区的影响[J]. 清华大学学报（自然科学版）, 2020, 60(10): 845-854.
XING Yue, LIU Jiahui, NI Guangheng. Impacts of urban canopy roughness on storm evolution and rainfall area. Journal of Tsinghua University(Science and Technology), 2020, 60(10): 845-854.
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2020, Vol. 60 
