An urban transport emission model for the Antwerp area

We present a detailed modelling approach which provides hourly emissions of CO, NOx, VOC, PM, SO2 and Pb for individual streets and road segments in the Antwerp area (20 km×20 km). The hourly emissions are computed as a function of road type, vehicle type, fuel type, traffic volume, vehicle age, trip length distribution and the actual ambient temperature. The traffic volumes are derived from an urban traffic flow model for the city of Antwerp, which contains a network with almost 2000 road segments. The traffic flow model has been implemented in a GIS environment. The emission factors used in the model are derived from the COPERT-II methodology. Cold start emissions and evaporation losses are included in the model. Results are shown for the hourly hot- and cold start emissions obtained for CO, NOx and VOC. For these pollutants a partial validation of the model results was carried out by comparing the COPERT-II emission factors with on-the-road traffic emission measurements carried out for gasoline passenger cars with a closed-loop controlled three-way catalyst.