Contribution of natural/biogenic sources to particulate matter levels over Europe : A multi-scale modelling study

A long-term assessment of biogenic/natural contribution to PM levels over Europe is still missing. We report on a multiyear modelling study including emissions for all relevant biogenic/natural sources calculated in the frame of the EU/FP6 NatAir project: vegetation, soils, sea, fires and volcanoes. Emissions were integrated into the regional scale chemistry transport model CHIMERE. Boundary conditions are updated with daily frequency using output from the global model GEOS-Chem, that includes an explicit calculation of desert dust emissions. Natural/biogenic sources are calculated to contribute ~40% to PM10 and ~25% to PM2.5 over Europe on a yearly basis, with more important contributions in Southern Europe (e.g. Iberian Peninsula) and during hot summers (e.g. 2003). The work is part of the Pilot Project QUITSAT, funded by the Italian Space Agency (ASI), contract I/035/06/0 http://www.quitsat.it