1Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, PSI Villigen, 5232, Switzerland
2Aix-Marseille Université, CNRS, LCE FRE 3416, 13331, Marseille, France
3Leibniz Institute for Tropospheric Research, Permoserstr 15, 04318, Leipzig, Germany
*now at: Department of Civil, Architectural, and Environmental Engineering and Department of Chemistry, Drexel University, Philadelphia, PA, 19104, USA
**now at: Department of Atmospheric Sciences, University of Washington, Seattle WA 98195, USA
***now at: WIL Research, 5203 DL 's-Hertogenbosch, the Netherlands
****now at: Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), UTAPRAD-DIM, Via E. Fermi 45, 00044 Frascati, Italy
Abstract. Secondary organic aerosol (SOA), a predominant fraction of particulate organic mass (OA), remains poorly constrained. Its formation involves several unknown precursors, formation and evolution pathways and multiple natural and anthropogenic sources. Here a combined gas-particle phase source apportionment is applied to wintertime and summertime data collected in the megacity of Paris in order to investigate SOA origin during both seasons. This was possible by combining the information provided by an aerosol mass spectrometer (AMS) and a proton transfer reaction mass spectrometer (PTR-MS). A better constrained apportionment of primary OA (POA) sources is also achieved using this methodology, making use of gas-phase tracers. These tracers allowed distinguishing between biogenic and continental/anthropogenic sources of SOA. We found that continental SOA was dominant during both seasons (24–50% of total OA), while contributions from photochemistry-driven SOA (9% of total OA) and marine emissions (13% of total OA) were also observed during summertime. A semi-volatile nighttime component was also identified (up to 18% of total OA during wintertime). This approach was successfully applied here and implemented in a new source apportionment toolkit.