There has recently been a general realization that more sophisticated modeling of land-surface processes can be important for mesoscale meteorology models. Land-surface models (LSMs) have long been important components in global-scale climate models because of their more complete representation of the surface energy and moisture budgets as well as their ability to represent and respond to changing climatic conditions and changing ecosystems. For mesoscale meteorology modeling such long-term changes are not important, however, seasonal changes in vegetation and synoptic changes in surface moisture conditions have important effects on meteorological simulations. Surface processes, such as soil moisture and canopy conductance, control the partitioning of net radiation into sensible, latent, and ground heat fluxes which in turn have strongly influenced ground level air temperature and humidity as well as PBL development. Since these parameters are especially important for air quality modeling, inclusion of a sophisticated LSM is critical for air quality modeling studies. Furthermore, the dry deposition component of the air quality model can greatly benefit by direct use of LSM parameters such as bulk stomatal conductance and aerodynamic resistance.