OSPM - A parameterised street pollution model

For many practical applications, as e.g. in support of air pollution manage ment, numerical models based on solution of the basic flow and dispersion e quations are still too complex. Alternative are models that are basically p arameterised semi-empirical models making use of a priori assumptions about the flow and dispersion conditions. However, these models must, be thoroug hly tested and their performance and limitations carefully documented. The Danish Operational Street Pollution Model (OSPM) belongs to this category o f parameterised models. In the OSPM, concentrations of exhaust gases are ca lculated using a combination of a plume model for the direct contribution a nd a box model for the recirculating part of the pollutants in the street. Parameterisation of flow and dispersion conditions in street canyons was de duced from extensive analysis of experimental data and model tests. Results of these tests were used to further improve the model performance, especia lly with regard to different street configurations and a variety of meteoro logical conditions.