Nitrogen oxides (NO_x) emissions and the oxidation products formed by photochemical interactions in the atmosphere are responsible for a significant fraction of both dry and wet acid deposition fluxes. In his paper a vertically-resolved, Lagrangian trajectory model is used to predict the diurnal variation of: NO, NO_2, NO_3, HONO, HONO_2, HO_2NO_2, RONO, RONO_2, RO_2NO_2, N_2O_5 and PAN over an urban airshed. Particular attention is given to the fate of nitric acid and its reaction with gaseous ammonia to form, aerosol phase, ammonium nitrate. A simple model for estimating the deposition fluxes of these species is also presented. A study of the fate of nitrogen oxides emissions, in the
South Coast Air Basin of southern California, is used to illustrate the procedures
