LINKING URBAN (STREET CANYON) MODELS WITH REGIONAL AIR QUALITY MODELS THROUGH URBAN BOUNDARY CONDITIONS

This contribution addresses the question of how detailed information from the urban canopy can be assimilated into regional models. This detailed information concerns, among others, road transport emissions, specific exchange and turbulence patterns in the built up canopy, and effects of roads and roughness elements on wind direction and wind speed. This information is typically obtained from detailed street canyon models in combination with traffic emission models. In order to integrate the dynamics of the urban canopy into regional air quality models, we propose the formulation of urban boundary conditions. The formulation has been tested and compared with measurements for benzene and NOx in the city of Antwerp, Belgium