Simulating Automobile Emissions in an Integrated Urban Model

The network component of an integrated urban model called IMULATE is interfaced with the MOBILE5.C emissions models. IMULATE produces estimates of traffic flows and average speeds on each link in an urban road network using a user equilibrium assignment algorithm. This information is combined with speed-dependent emissions factors generated by MOBILE5.C to calculate estimates of the three types of emissions on a link-by-link basis. The combined models are implemented for the Hamilton, Ontario, Canada, metropolitan area. Simulations are conducted to illustrate the spatial patterns of emissions in the morning peak period and to demonstrate the impact of congestion on emissions estimates. The incorporation of detailed network performance information yields significant benefits in the estimation of regional automobile emissions.