A street thermal environment study in summer by the mobile transect technique

To estimate the impact of street characteristics on the thermal environment in an urban street canyon in a hot and humid region, transect data were used to analyze the relation between three factors (urban green ratio, building ratio, and height-to-width ratio) and air temperature in two streets in Taichung City, Taiwan. In this study, air temperature data were collected by transects at four different level heights (1, 2, 3, and 4 m height) in two streets; meanwhile, the use of three street characteristics data calculated by geographic information system (GIS) data which can represent the environment conditions of 34 measured locations. The analysis results shows that the air temperature significantly correlated with height-to-width ratio (r = 0.481), green ratio (r = 0.729), and building ratio (r = 0.654), respectively, at night. In conclusion, this study demonstrates that increasing the green ratio and decreasing the building density are important strategies to mitigate urban warming and to create a comfortable thermal environment.