Regional planning or neighborhood design? curbing air pollution exposure of pedestrians and other road users in urban micro-environments

最近，研究已经确立了建筑环境、体育活动和肥胖之间的密切联系。这使得人们普遍认为紧凑、混合用途的城市形式降低了对汽车的依赖，并促进了其他交通方式的发展。尽管对行人友好的环境有好处，但它们也可能带来风险：紧凑的混合用途城市形式促进了活跃的交通，但它可能会通过将污染物困在街道峡谷中从而放大街道空气污染来减少交通排放的分散。拟议的研究项目通过探索设计指南和创新的区域政策的实施来解决这一困境，这些政策可以改善街道空气质量，同时保持建筑密度、活动集中度和行人友好型建筑环境所需的交通流量。我们将特别处理四个主要目标：

Recently, research has established a strong association between the built environment, physical activity, and obesity. This has led to a general understanding that compact, mixed-use urban form results in lower automobile dependency and promotes alternative modes of transport. Despite the benefits of pedestrian-friendly environments, they could also pose risks: while compact, mixed-use urban form promotes active transportation, it may reduce the dispersion of traffic emissions by trapping pollutants in street canyons thus magnifying street-level air pollution. The proposed research program addresses this dilemma by exploring the implementation of design guidelines and innovative regional policies that improve street-level air quality while maintaining the building density, concentration of activities, and traffic flows that pedestrian-friendly built environments require. In particular, we will address four main objectives: 1- Improve current understanding of personal exposure in transport micro-environments 2- Assess the effects of road design, traffic, and various controls on exposure 3- Assess the impacts of local-level interventions on regional air quality 4- Analyze the justice of exposure at the regional level For this purpose, an integrated simulation of traffic, transit operations, vehicle emissions, air quality, and pedestrian movements will be developed for selected urban micro-environments in Montreal. In addition, a regional air quality model for Montreal will be developed and linked with the local-scale models thus generating a hybrid model of air quality and exposure. The proposed program will first have a great impact on the science; there is still a great deal that is not well understood in terms of the interactions between the built form and environmental quality. It will also create a positive change in planning agencies by introducing a new dimension to design and decision-making.