A minimum set of components, namely, NO, NO2, NO3 , and O3 describing the day cycle of nitrogen oxides in the polluted troposphere is determined. The possibility of the range-resolved lidar measurements of NO3 mass concentrations is demonstrated. The DIAL parameters needed for the simultaneous measurements of NO, NO2, NO3 , and O3 mass concentrations and relative distribution of an aerosol are determined with the purpose of studying the mechanism for the formation of the photochemical smog.