AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Abstract View
Brown Carbon Aerosol in Fresh and Aged Biomass Burning Emissions: Contribution of Individual Compounds
ANDREY KHLYSTOV, Vera Samburova, Jessica Connolly, Chiranjivi Bhattarai, Deep Sengupta, Adam Watts, Hans Moosmuller, Desert Research Institute
Abstract Number: 600 Working Group: Aerosols, Clouds, and Climate
Abstract Brown carbon (BrC) has been shown to be a potentially important contributor to light absorption by atmospheric aerosols. A significant part of atmospheric BrC has been associated with wildfires, such as forest and peat fires. No attempt has been made so far to quantitatively analyze the contribution of individual organic species and different compound classes, including HUmic LIke Substances (HULIS), polycyclic aromatic hydrocarbons (PAHs), and other water-soluble and non-water-soluble organic species, both primary and secondary, to light absorption by biomass burning aerosols. We will report optical properties and chemical composition of fresh and aged (using the Aerodyne potential aerosol mass reactor) biomass-burning emissions measured during laboratory combustion of fuels from five different locations around the world (boreal forest and peat land, Siberia, Russia; extra tropical forest, Oregon, USA; tropical forest and peat, Brazil; coastal swamp peat, Florida, USA; mixed conifer forest, Sierra Nevada mountains USA), covering the main wildfire-prone areas of the globe. Chemical characterization of particulate and gaseous species collected on filters and XAD cartridges includes gas chromatography mass spectrometry (GC-MS; Varian 4000 Ion Trap and Scion Triple Quad MS/MS), ultrahigh performance liquid chromatography coupled to evaporative light scattering detector (Waters UPLC-ELSD), and Total Organic Carbon analyzer (TOC; Shimadzu TOC-VCSH). In addition to a detailed chemical characterization, we will discuss contribution of individual compounds to light absorption by aerosol material extracted with polar and non-polar solvents. The contribution of an individual compound is calculated using its absorption efficiency, as measured using UV-VIS spectrophotometer, and concentration obtained for each aerosol extract.