Estimating the contribution of commercial vehicle movement to mobile emissions in urban areas

Metropolitan scale studies of transport-based air pollution have emphasized inputs from the passenger vehicle fleet, with minimal attention given to the role of urban goods movement. Furthermore, little is known about the spatial distribution of transport related emissions. This study uses an integrated urban land use and transport model (IMULATE) for Hamilton, Canada, to examine the contribution of trucking to the spatial distribution of mobile emissions in urban areas. Using tube data and intersection counts for commercial vehicles, we produce an origin-by-destination matrix of commercial trips. The transportation module of IMULATE was adjusted to estimate the differential traffic volume, due to the presence of commercial trips, in all the links of the transport network. These estimates are then translated into emissions of carbon monoxide (CO), nitrogen oxides (NOx), hydrocarbons (HC) and particulates. The results demonstrate the need to control for urban commercial vehicle movement when attempting to estimate mobile emissions in urban areas.