A comparison of three street canyon models with measurements at an urban station in Antwerp, Belgium

We discuss the application of three street canyon models in order to evaluate the concentration levels of NOx, SO2, PM10 (1999/ 30/EC), CO and benzene (2000/69/EC) in one of the main passage roads in the city of Antwerp, the ‘‘Plantin en Moretuslei’’ in the city of Antwerp. The model results are based on identical urban transport emission input data for Antwerp and on the same meteorological input data derived from nearby meteorological towers. Background values are obtained from a regional air quality model, which is used as a reference model for environmental reporting in Flanders. For NOx, SO2, PM10 and benzene the results are compared with hourly observations from a monitoring station in the ‘‘Plantin en Moretuslei’’. It was found that the annual averages are relatively well captured by the models. The higher percentiles (98th, 99th) are underestimated, due to the lack of hourly variation in the background concentration. A more sophisticated approach is needed to model these background concentrations more adequately.