HBCU-Excellence in Research: Biomass Burning Aerosol-Molecular Level Characterization of Aging Conditions on Optical and Chemical Properties

The goal of this project is to improve knowledge of the optical properties of biomass burning (BB) aerosol, especially those derived from the combustion of African biomass fuels. This research is directed toward the study of changes in the optical properties of BB aerosol due to changes in the burning conditions during combustion. This project is designed to enhance atmospheric chemistry and physics research training capacity at North Carolina A&T State University (NCAT).

Collaborative laboratory studies will take place at NCAT, as well as at the University of North Carolina at Chapel Hill.

The research will address the following questions: (1) How does the molecular-level composition of African fuel-derived BB-derived aerosol change as a function of aging conditions (i.e., fresh versus dark/photochemical/cloud water aging) and how do these aerosol optical properties (i.e., single scattering albedo, refractive index, and modified combustion efficiency) change because of any potential molecular-level chemical changes? (2) Does aging of primary (fresh) BB-derived aerosol and gas emissions alter the aerosol physicochemical properties, including volatility, density, morphology, and water-solubility? (3) what is the relationship between morphology (fractal dimensions) and modified combustion efficiency and how does this influence the criteria for selecting the correct method (Mie, Rayleigh-Debye-Gans or T-matrix approach) to modeling optical properties and the resulting extraction of RIs? (4) Can BB-derived water-soluble gas emissions undergo cloud water processing to yield secondary organic aerosol after cloud droplet evaporation? and (5) What are the precursors for African fuel- derived water-soluble gas emissions?

This project is funded by the Atmospheric Chemistry, Excellence in Research, and Integrative and Collaborative Education and Research Programs at NSF. This effort provides opportunities for students and faculty from all participating institutions to work collaboratively.

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.