Biomass Burning Flux Measurements of Trace Gases and Aerosols (BB-FLUX) Using Solar Occultation Flux (SOF) on the Wyoming King Air

University Of Colorado At Boulder, Boulder CO

Investigators

Abstract

The BB-FLUX project is part of a larger collaborative effort (WE-CAN) focused on the study of the emissions and evolution of western U.S. wildfire plumes. A field campaign is scheduled to take place in the late summer of 2018 near Boise Idaho. The emission fluxes of a number of gases will be measured and compared with model predictions. The results will provide significantly improved quantification of wildfire emissions and provide important new information to fire and fuel managers, and to air quality regulators. The University of Colorado airborne Solar Occultation Flux (SOF) instrument will be used to calculate quantitative fluxes for a large number of gases. Measurements will be made simultaneously above the aircraft, during aircraft transects below plumes, with fluxes being quantified using the mass balance method. The project combines remote sensing of CO and other trace gas columns by SOF (e.g., H2O, NO, NO2, NH3, HONO, HCHO, small VOCs, CH3OH, HCN, HCOOH, other small acids), temperature and humidity profiles, and plume injection height (Lidar), with select in-situ sampling (CO, CO2, H2O, O3, wind speed, particle size distributions). BB-FLUX has the following four objectives: 1) quantify emission fluxes of CO, CO2, other gases, and particle volume for different fuel types (boreal forest, temperate forest) and burn conditions (flaming, smoldering); 2) characterize plume injection height from plumes that travel decoupled from the ground (top of boundary layer, free troposphere), and evaluate predictions by atmospheric models; 3) study radical sources and secondary plume chemistry that leads to secondary production of O3 and changes in the particle size distribution as plumes age. Finally, SOF column measurements complement the detailed in-situ sampling of emission ratios on the C-130 aircraft. By probing similar fires using both aircraft, this project 4) explores synergistic benefits of remote sensing and in-situ observations to quantify speciated total emission fluxes from wildfires. 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.