jailcd2019-029: The Effects of Green Roof Layouts on Air Temperature and Relative Humidity at the Pedestrian Level of Street Canyons in China’s Hot-Humid Regions

Abstract

To mitigate the urban heat island effect and improve the air temperature and relative humidity at the  pedestrian level during summer, this paper focused on the layout of green roofs in China’shot-humid regions. First,  through  experimental  testing  in  the  Wangma  community,  Changqing  Street,  Shangcheng  District  Hangzhou city, the simulated values near ground height (1.4m) were relatively close to the measured values  of air temperature and relative humidity. Then, we analyzed the parameters that affect the air temperature and  relative humidity at the pedestrian level (1.4m) by changing the green roofs’ heights, depths, and widths. The  simulation showed the maximum value of the height of green roofs was 10 meters of air temperature and 20  meters of relative humidity at the pedestrian level. The limiting effect value on the depth of green roofs was  20 meters. The cooling effect did not increase with increases in the width; while moisture in the canyon  increased with increases in the width of the green roofs. This will provide a computer strategy of simulation  to assist the government in implementing green roofs.