Improving the determination of the contribution of road traffic emissions to PM10 urban concentrations through PMF modelling

Road traffic is a major source of particulate matter in urban environment and it is now well-established that exposure to particulate matter from road traffic emissions have deleterious impacts on human health. Thanks to stringent regulations, vehicular exhaust emissions have strongly decreased and non-exhaust particulate emissions (particles resuspended by moving traffic and those from the wear of brakes, tyres, road surface…) now contribute to a large part of particulate vehicular emissions. The establishment of efficient mitigation measures requires a better knowledge of both exhaust and non-exhaust vehicular emissions.
The Positive Matrix Factorization (PMF) has been widely used to apportion sources of PM10. However, wide ranges of emission processes (combustion, mechanical wear, resuspension), involving various pollutants (organics from exhaust and tyres, metals from brakes, minerals from road wear…) and related physical processes, are responsible for difficulty to properly apportion the contribution of vehicular emissions to urban PM10 concentrations.
The objective of this internship is to better quantify the contributions of road dust resuspension/road abrasion, brake wear and vehicular exhaust to PM10 urban concentrations. This involves two main steps.
The first one will be to check the relevance of exhaust and non-exhaust emission profiles established within the PM-DRIVE programme for the Grenoble ring road to other French traffic sites. The evolution of these emission profiles at urban background sites will be then examined. For that the very large databases acquired within the SOURCES programme will be analysed.
The second step will be to introduce appropriate constraints on the PMF solution to provide a more definitive road traffic source resolution.

Pour candidater : Adresser un CV et une lettre de motivation par email à l’adresse ci-dessous
aurelie.charron univ-grenoble-alpes.fr et Jean-luc.jaffrezo univ-grenoble-alpes.fr