SIMULATED URBAN CLIMATE RESPONSE TO MODIFICATIONS IN SURFACE ALBEDO AND VEGETATIVE COVER

Three-dimensional meteorological simulations have been conducted to in vestigate the potential impact of urban surface characteristic modific ations on local climate. Results for a base case simulation for the Lo s Angeles basin are compared to results from cases in which urban albe do or vegetative cover are increased. The methodology for determining the distribution and magnitude of these simulated surface modification s is presented. Increasing albedo over downtown Los Angeles by 0.14 an d over the entire basin by an average of 0.08 decreased peak summertim e temperatures by as much as 1.5 degrees C. This level of albedo augme ntation also lowered boundary layer heights by more than 50 m and redu ced the magnitude and penetration of the sea breeze. A second simulati on, in which vegetative cover was increased, showed qualitatively simi lar impacts. The results from these simulations indicate a potential t o reduce urban energy demand and atmospheric pollution by 5%-10% throu gh application of reasonable surface modification strategies.