Modeling traffic-related air pollution in street canyons of Beijing

It is important to develop a general model to accurately simulate the air p ollution in urban street areas. In this paper, the Operational Street Pollu tion Model (OSPM) initially developed in Denmark is tested with measured da ta from a relatively wide and open street in Beijing. Major factors influen cing the dispersion, such as emission factors, stationary source emissions, and solar radiation, are analyzed. Results show that the model can reflect the basic dispersion pattern in the street but gives systematically higher concentrations. After modifications to estimate street-level wind speed in the model, performance is obviously improved.