Airborne and ground-based measurements of aerosol optical depth offreshly emitted anthropogenic plumes in the Athabasca Oil Sandsregion

Abstract. In this work we report the airborne aerosol optical depth (AOD) from measurements within freshly-emitted anthropogenic plumes arising from mining and processing operations in the Athabasca Oil Sands Region (AOSR) in the context of ground-based AERONET climatological daily averaged AODs at Fort McMurray (Alberta, Canada). During two flights on June 9 and June 18, 2018, the NASA airborne 4STAR (Spectrometers for Sky-Scanning, Sun-Tracking Atmospheric Research) sunphotometer registered high fine-mode (FM,