Airborne measurements of the spatial distribution of aerosol chemical composition across Europe and evolution of the organic fraction: Supplementary material

1 Scope The supplementary material outlined in this document is provided in order to present the meteorological context of the flight operations and support the analysis techniques and data quantification steps outlined in the main paper. The meteorological fields corresponding to each flying period are presented and further information regarding the photochemical context of the operations is presented. Further details regarding the volume closure between the Aerosol Mass Spectrometer (AMS) and the Passive Cavity Aerosol Spectrometer Probe (PCASP) are discussed. Comparison of the esti- mated HOA with primary combustion tracers is included. The relationship between the fractional contribution of Low-Volatility Oxygenated Organic Aerosol (LV-OOA) to the organic mass and the normalised organic signal at m/z 44 is also shown. Further information is provided regarding the Positive Matrix Factorisation (PMF) analysis ex- amples from the main text, as well as a summary of some PMF diagnostics for the whole dataset. The PMF analysis was performed using the tools presented by Ulbrich et al. (2009).