Quantifying the effects of land-use and socio-economics on the generation of traffic emissions and individual exposure to air pollution

摘要

This paper presents a modeling framework developed for the City of Montreal, Canada, and isintended to quantify two indicators that can explain the spatial distribution of traffic-related airpollution at a metropolitan level. The indicators are estimated at the level of the traffic analysiszone (TAZ) and include: (1) the average level of emissions generated per individual, and (2) thelevel of emissions occurring in a zone as a proxy for air pollution exposure. A regional trafficassignment model is extended with capabilities for emission modeling at an individual trip levelwhile taking into account vehicle (type, age) and trip attributes (road type, speed, volume). Weobserve that individuals who generate higher emissions from travel tend to reside in areas withlower exposure to traffic emissions while individuals associated with low levels of travelemissions (e.g. travel smaller distances, conduct less trips, use alternative modes) reside in areaswith high levels of traffic pollution. A regression analysis of the two indicators against a set ofland-use and socio-economic variables shows that generated emissions per individual arepositively associated with car ownership and larger vehicles, while being negatively associatedwith ownership of newer vehicles, and location in dense and walkable neighborhoods with highlevels of commercial land-use. Meanwhile, exposure to emissions is positively associated withdense and walkable neighborhoods and negatively associated with car ownership and largervehicles. These findings indicate major inequities in the generation of and exposure to traffic19related air pollution.