Multisite characterization of concurrent black carbon and biomass burning around COVID-19 lockdown period

Abstract The Magee Scientific Model AE33 Next Generation Aethalometer, installed at Amity University Haryana (AUH), Panchgaon (rural station) has been operated round-the-clock and obtained high-resolution (1–5 Minutes) observations of Black Carbon (BC) mass concentration at seven different sensing wavelengths (ranging from UV to NIR). For each observation, contribution from Biomass Burning (BB, in percent) to the BC has also been recorded. These measurements have been analyzed to segregate different sources, responsible for BC at this rural station. The results reveal that the major contributor is ‘traffic’ (fossil-fuel diesel emissions), followed by ‘biomass smoke’, wood-burning activities. The diurnal variation in BC and associated BB over this study area reveals a significant maximum around 0900 h and minimum around 1600 h. These maximum and minimum concentrations are attributed to transport activities during morning and ascending of local atmospheric boundary-layer height. The results also exhibit a strong affinity between BC mass concentration and coincident CO2 and PM2.5 mass concentrations. Synchronous BC measurements have also been organized over two more locations, namely, Bhopal (urban station) and Mahabaleshwar (high-altitude station). The black carbon aerosol transport through long-range air mass back-trajectories is explained.