P32     Contrasting responses of urban and forest surface temperature to heat waves.

Wang, Liang, and Dan Li, Boston University

Understanding differences in responses to heat waves between urban and forest sheds light on a possible path to mitigate heat stress in cities. In this study, we attribute the daytime surface temperature difference between urban and forest to atmospheric and surface biophysical factors based upon simulations using the Weather Research and Forecast (WRF) model over Boston throughout 10 heat wave cases. Further, we examine how such differences in surface temperature between urban and forest change when a heat wave comes and leaves and try to identify the key contributor. Results show that there exist synergistic interactions between heat waves and urban-forest surface temperature differences in Boston, which can be attributed mostly to the surface resistance to water vapor transfer between the land and the atmosphere.