RAPID: Characterization of the Influence of Daytime and Nighttime Oxidative Aging Processes on the Physicochemical Properties of Laboratory-Generated Biomass Burning Emissions

This RAPID project will enable research on both the daytime and nighttime oxidation of biomass burning emissions and their potential to affect the atmospheric radiative balance through light absorption and cloud formation. It will be conducted in conjunction with a project supported by the Pacific Northwest National Laboratory’s Environmental Molecular Sciences Laboratory to conduct laboratory studies that mimic the daytime and nighttime oxidative aging of realistic biomass burning aerosols. The knowledge gained through this RAPID project will lead to a better understanding of how wildfire emissions influence atmospheric ice formation and light absorption efficiency and will aid in the identification of molecular tracers for daytime and nighttime oxidative aging processes. Biomass burning emissions will be generated in the controlled combustion chamber at EMSL and oxidized in Aerodyne’s new Dual Oxidation Flow Reactor (OFR), that can simultaneously study the oxidative aging processes of emissions initiated by both the hydroxyl radical (OH) and the nitrate radical (NO3). Measurements of ice-nucleating particle formation and light extinction/scattering coefficients will inform future studies of cold cloud formation potential and radiative forcing associated with fresh, OH-oxidized, and NO3-oxidized wildfire emissions. The knowledge gained through this research will lead to a better understanding of how wildfire emissions influence air quality over the life cycle of the fire. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.