AAAR 36th Annual Conference October 16 - October 20, 2017 Raleigh Convention Center Raleigh, North Carolina, USA
Abstract View
Climate-Relevant Compounds Produced from Burning Forest Fire Fuels in Conjunction with the FIREX Campaign
LAUREN FLEMING, Sergey Nizkorodov, Peng Lin, Alexander Laskin, Julia Laskin, University of California, Irvine
Abstract Number: 56 Working Group: Aerosol Chemistry
Abstract Forest fires are increasing in intensity and frequency in North America due to 20th century land practices and climate change. This increase in particulate emissions, in the form of black carbon and organic carbon, in turn affects climate. Biomass burning organic aerosol is unique in that it contains highly absorbing organic molecules in the smoke plume. Our aim was to identify the main visible-light-absorbing molecules produced from burning a variety of forest fire fuels. Fuels were burned at the Missoula Fire Lab in the first phase of the FIREX campaign. Filter samples were extracted in solvents spanning a wide range of polarities and analyzed using an HPLC-PDA-HRMS platform. We found that the types of chromophores in smoke depend strongly on the fuel. Additionally, some filter samples were photolyzed with 300 nm radiation. This analysis made it possible to determine whether the identified chromophores are photo stable or photo labile in the atmosphere. This work provides an improved understanding of the main brown carbon molecules in forest fire smoke from different parts of the United States and Canada, and of the way these molecules are transformed in the atmospheric environment.