Overview of aerosol properties associated with air masses sampled by the ATR-42 during the EUCAARI campaign (2008)

摘要: Abstract. Within the frame of European Aerosol Cloud Climate and Air Quality Interactions (EUCAARI) project, Meteo-France aircraft ATR-42 performed 22 research flights over central Europe North Sea during intensive observation period in May 2008. For campaign, was equipped to study aerosol physical, chemical, hygroscopic optical properties, as well cloud microphysics. flights, retroplume analyses along flight tracks were with FLEXPART order classify air masses into five sectors origin, allowing for a qualitative evaluation emission influence on respective parcel. This shows that extensive parameters (aerosol mass number concentrations) show vertical decreasing gradients some maximum concentrations (mainly organics) an intermediate layer (1–3 km). The observed (in boundary (BL): between 10 30 μg m−3; lower free troposphere (LFT): 0.8 14 m−3) are high especially comparison 2015 norms PM2.5 (25 previous airborne studies England (Morgan et al., 2009; McMeeking 2012). Particle size distributions larger fraction particles accumulation range LFT compared BL. chemical composition submicron is dominated by organics BL, while ammonium sulphate dominates aerosols LFT, originated from north-eastern (~ 80%), also experiencing nucleation events transport. As consequence, first particle CCN acting ability, shown CCN/CN ratio, second average values scattering cross sections optically active (i.e. coefficient divided concentration) increased