The Livermore regional air quality model: I. Concept and development

By using the Eulerian form of the mass conservation equation integrated vertically from the surface to the base of the inversion, two regional air quality models (LIRAQ-1 and LIRAQ-2) have been developed for use in the San Francisco Bay Area. The models consider the complex topography, changing meteorology and detailed source emission patterns in generating surface and vertical average pollutant concentrations with grid resolutions of 1, 2 or 5 km. The focus of LIRAQ-1 is the treatment of transport and dispersion of relatively nonreactive species, accomplished through use of a sophisticated transport prescription. The LIRAQ-2 model, employing a simpler transport scheme, treats photochemically active pollutants and incorporates a photochemical reaction set involving 19 species.