Characterization of traffic-related particulate matter at urban scale

Road traffic is recognized as a significant source of particulate matter (PM), especially in urban areas, where exceedances of the legislation PM limit values is one of the main environmental concerns.Therefore, the development and implementation of methodologies allowing detailed characterization of PM within urban areas are required to find potential solutions to decrease PM levels.This work aims to provide a detailed characterization of traffic-related PM concentrations at urban scale by using an integrated modelling approach and in-situ aerosol measurements.For this purpose, a modelling cascade based on transportation-emission-dispersion approach was implemented for a medium-sized Portuguese city (Coimbra).Moreover, optical aerosol measurements were obtained from an experimental field monitoring campaign (June 2017) implemented at a city 'hot-spot' to provide relevant in-situ data on number, surface and mass concentrations distribution into 31 size ranges from 0.25 to 32 μm.The spatial distribution of the exhaust and non-exhaust traffic-related emissions is analysed and discussed addressing their contribution to the PM pollution.The current study evidences the importance of road traffic non-exhaust emissions and demonstrates the usefulness of the integrated modelling approach in the mobility policy relevant context.