The effects of land use in meteorological modeling: implications for assessment of future air quality scenarios

In recent years, there has been an increased use of prognostic meteorologic al models to assess current and future air quality related problems. Often, these meteorological models are applied in their forecasting mode with cur rent land use/land cover patterns and data assimilation techniques to gener ate historical meteorological data for use in air quality models. In this s tudy, we examined the sensitivity of land use/land cover on the predicted m eteorological fields, and the implications for examining air quality in a f uture year. A community-based mesoscale meteorological model (MM5-Version 1 ) was applied to the northeastern US urban corridor under two scenarios, on e with the existing land use/land cover (base case), and the second reflect ing a hypothetical change in about 40% of the base case urban grid cells to deciduous forest. A comparison of the two meteorological fields reveals su bstantial localized differences in surface temperature and zonal wind speed s. These findings suggest reevaluation of the practice of using historical meteorological fields to assess future air quality, especially if one expec ts large changes in land use patterns. (C) 2000 Elsevier Science Ltd. All r ights reserved.