Form Submission: Participation Entry

Abstract: 
Microclimate Urban Heat Island (UHI) is considered to subject to more complicated underlying mechanism compared to the UHI effect at a greater scale. A better understanding of how microclimate UHI responds to the change of urban landscape, i.e. tree canopy cover and city morphology, is urgent. An innovative methodology, mobile measurement, was used to explore the variation of street-level meteorological factors in New Haven, Connecticut. It was found that temperature and humidity in the city subject to different local climatic mechanisms. The humid climate, characterized by the effect of daytime sea breeze, has negative correlation between temperature and humidity anomaly: the heat island corresponds with the dry island. On the contrary, a more typical urban climate without the sea breeze shows positive correlation between temperature and humidity anomaly: the heat island corresponds with wet island. The urban area is not persistently drier than the surrounding rural land. For the urban climate, tree canopy cover has strong cooling effect in terms of dry bulb temperature, while the shadow-related cooling is weaker. In terms of wet bulb temperature, building shadow fraction mitigates the UHI the most significantly, while the tree-related cooling becomes trivial. For the future work, measurements in the different times of a day, different weather conditions will help to clarify the mechanism of UHI formation more profoundly.