Environmental management of ozone in Beirut urban areas

Urban tropospheric ozone (O₃) concentrations can reach 40 folds its background level due to traffic‐induced emissions and extensive industrial activities. As such, O₃ has become a pervasive air pollution problem in urban areas despite major efforts to control its precursors. In this paper, O₃ formation mechanisms are briefly described, countrywide emissions with emphasis on O₃ precursors are summarized, and field measurements of O₃ background levels and its precursors in an urban area are presented. Simulation results using a photochemical air quality model including a sensitivity analysis with respect to design ratios and mixing heights are then presented. Mitigation alternatives and policies to control O₃ formation are examined in the context of country‐specific characteristics.