AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Optical Characterization of Fresh and Photochemically-Aged Aerosols Emitted from Laboratory Siberian Peat Burning
Michealene Iaukea-Lum, Chiranjivi Bhattarai, Deep Sengupta, Vera Samburova, Andrey Khlystov, Adam Watts, W. Patrick Arnott, HANS MOOSMULLER, Desert Research Institute
Abstract Number: 328 Working Group: Biomass Combustion: Emissions, Chemistry, Air Quality, Climate, and Human Health
Abstract Carbonaceous aerosols emitted by biomass burning greatly influence radiative forcing and climate on regional and global scales. In this study, we characterized the optical properties of emissions from the laboratory combustion of Siberian peat. This fuel frequently burns in large and long-lasting wildland fires affecting boreal and arctic ecosystems. Peat burns mostly in smoldering combustion, emitting large amounts of organic and brown carbon. Here, we characterized the optical properties of both fresh and photochemically-aged emissions. Atmospheric aging was simulated using an Oxidation Flow Reactor (OFR), which was operated with different ultraviolet actinic fluxes to simulate atmospheric aging on timescales ranging from days to months. Aerosol characterization utilized real time instruments including a photoacoustic three-wavelength soot spectrometer (PASS) and a scanning mobility particle sizer (SMPS) with additional analysis of aerosols collected on quartz and Teflon filters. Three-wavelength optical properties of fresh and aged aerosols including single scattering albedo and absorption and scattering Ångström exponents will be presented. In addition, retrieval of complex refractive indices will be discussed.