Carbon and Oxygen Volatility Distributions of Biomass Burning Organic Aerosols Undergoing Oxidation and Dilution
PURUSHOTTAM KUMAR, James Hurley, Nathan Kreisberg, Tianchang Xu, Braden Stump, Patricia Keady, Nga Lee Ng, Gabriel Isaacman-VanWertz, Virginia Tech
Abstract Number: 404
Working Group: Combustion
Abstract
The volatility of aerosols is a complex parameter which is important for understanding atmospheric chemistry and improving model predictions. For this purpose, a recently developed instrument “ChemSpot” was deployed at the Georgia Wildfire Simulation Experiment (G-WISE). The ChemSpot instrument collects aerosols into a custom-designed collection and thermal desorption cell. The collected particles are then thermally desorbed and transferred to a Flame Ionization Detector (FID) and a downstream CO2 detector. The slow thermal desorption and this combination of detectors provide volatility-resolved measurements of aerosol carbon and the estimation for oxygen content. In G-WISE, biomass-burning organic aerosols generated by burning biomass collected from 3 different ecoregions (Piedmont, Coastal Plains, and Blue Ridge) from the state of Georgia were studied under different conditions using a variety of instrumentation. Initial results from the ChemSpot data show that the majority of the particle carbon and oxygen are present in the logC* bins of 0 to 2. Changes in the volatility distributions for aerosols generated by different types of biomass will be presented (fresh and aged aerosols). Comparisons to the measurements from another collocated instrument measuring the volatility distribution of oxygen-containing species will also be discussed.