This paper analyses the extent to which such emission reductions can influence local levels of air pollution concentration. The analysis is based on the application of the road traffic assignment model SATURN to the urban area of Chester, in order to simulate traffic flow conditions, in conjunction with a Gaussian plume dispersion model, which estimates the concentration of air pollutants for each link within the network. The conventional dispersion model has been adapted to account for actual traffic emission data resulting from typical driving operating modes (cruising, decelerating, accelerating and idling). Initially, the effects of reductions in vehicle emission rates resulting exclusively from engine resulting exclusively from engine improvements over the last decade are analysed. Further, Yearly scenarios are created to the Year 2005, showing the effect of traffic growth and the increasing penetration of catalytic converters into the vehicle market. (A)
Abstract