Modeling seasonal changes in organic aerosol composition at the puy de Dôme (France)

Abstract

In the atmosphere, a significant fraction of organic aerosol (OA) makes up the particulate matter. Since OA consists of thousands of complex molecules, uncertainties remain concerning their sources and atmospheric processes leading to their transformation (Hallquist M et al. Atmos Chem Phys 9:5155–5236, 2009). OA are, in principle, divided into two categories: Primary organic aerosol (POA), which is emitted directly into the atmosphere, and secondary organic aerosol (SOA), which is formed by the photo-chemical oxidation of volatile organic compounds (VOC). VOC emissions and consequently OA formation are strongly linked to the season of the year. To that purpose, simulations were performed in autumn (September 2008) and summer (June 2010) with the WRF-CHEM model including more precisely RACM (Stockwell WR et al. J Geophys Res 102:25847–25879, 1997) chemical mechanism for gas phase associated with MADE for aerosols (Ackermann IJ et al. Atmos Environ 32(17):2981–2999, 1998) and VBS (Ahmadov et al. J Geophys Res 117:D06301, 2012) for SOA. Moreover, model outputs are compared with measurements performed during each season (Freney EJ et al. Atmos Chem Phys 11:13047–13059, 2011) at the puy de Dôme monitoring site which is located in central France (45°46 N 2°57 E) and is a part of the ACTRIS (Aerosols, Clouds, and Trace gases Research InfraStructure) and GAW (Global Atmospheric Watch) network.