Assessing individual activity-related exposures to traffic congestion using GPS trajectory data

Abstract Accurately assessing individual exposures to traffic congestion and traffic-related emissions is important for evaluating the impact of traffic congestion on human health. Existing studies on individual exposures to traffic congestion focus mainly on commuting trips, while our understanding of individual exposures to traffic congestion during different types of trips is very limited. This study examines individual exposures to traffic congestion during various types of trips by using taxi GPS trajectory and POI datasets in Wuhan, China. We first infer individual trip purposes from the GPS trajectories based on the attractiveness of the POIs and Bayesian rules. Individual exposures to traffic congestion associated with different types of trips are then evaluated. We also estimate exposures to excessive traffic-related emissions due to traffic congestion associated with different types of trips. The results show that individual exposures to traffic congestion are more related to the space-time rhythm of traffic flows than the types of trips or activities conducted. The findings indicate that only considering commuting trips would underestimate individual exposures to traffic congestion and excessive traffic-related emissions. This study provides a more detailed picture of how people conducting different types of trips and activities are exposed to traffic congestion. It advances our understanding of individual exposures to activity-related traffic congestion in space and time.