Emerging urban form ? Emerging pollution: Modelling endogenous health and environmental effects of traffic on residential choice.

Air pollution bears severe health and environmental impacts and is of increasing concern to urban planners but densification strategies have ambiguous impacts. We analyse how households’ aversion to generating and being exposed to traffic pollution at the residential place and during their commute influences emerging urban structures and how these structures in turn affect pollution exposure and the residential choice of households. Resulting spatial patterns are difficult to predict because of this feedback and the spatial form of urbanisation and road networks. We address this complexity with a micro-economic agent-based residential choice model dynamically coupled with a cellular automata model for pollution dispersion and its perception in neighbourhoods. Our simulation experiments on a theoretical grid suggest that the spatial scale of this perception is important.We also find that if both health and environmental concerns are to be addressed, a combination of reducing commuting distances and preserving local green spaces is necessary. In particular, locally dispersed urban development and intra-urban green spaces next to busy roads can mitigate pollution exposure.