Ozone Production in Smoke Plumes from Crop Residue and Prescribed Burns

Agricultural and prescribed burns, a common practice globally, contribute large amounts of trace gasses to the atmosphere. The impacts of these burns on ozone pollution and air quality are not yet well characterized. Here, we utilize data from the 2019 NASA-NOAA FIREX-AQ field campaign to study ozone production associated with small scale biomass burning events of crop residues and other prescribed fuels in the Southeast US. We customize a photochemical box model with emissions ratios of volatile organic compounds (VOC) and nitrogen oxides (NOx) for eight fuel types (slash, piles, shrubland, grassland, corn, rice, soybean, and winter wheat). By initializing with carbon monoxide and ozone concentrations for photochemically young plumes, we estimate each fuel’s ozone production potential as the plume ages. We characterize the VOC composition, NOx emissions, and combustion efficiency within and between individual fuel types to assess the modeled variability in ozone production. In demonstrating the potential implications for air quality that result from agricultural and prescribed burns, we present a case for a more extensive approach to managing and modeling biomass burning practices in the southeastern US.