title: Impacts of Combustion Conditions and Photochemical Processing on the Light Absorption of Biomass Combustion Aerosol.
abstract: The aim was to identify relationships between combustion conditions, particle characteristics, and optical properties of fresh and photochemically processed emissions from biomass combustion. The combustion conditions included nominal and high burn rate operation and individual combustion phases from a conventional wood stove. Low temperature pyrolysis upon fuel addition resulted in "tar-ball" type particles dominated by organic aerosol with an absorption Ångström exponent (AAE) of 2.5-2.7 and estimated Brown Carbon contributions of 50-70% to absorption at the climate relevant aethalometer-wavelength (520 nm). High temperature combustion during the intermediate (flaming) phase was dominated by soot agglomerates with AAE 1.0-1.2 and 85-100% of absorption at 520 nm attributed to Black Carbon. Intense photochemical processing of high burn rate flaming combustion emissions in an oxidation flow reactor led to strong formation of Secondary Organic Aerosol, with no or weak absorption. PM1 mass emission factors (mg/kg) of fresh emissions were about an order of magnitude higher for low temperature pyrolysis compared to high temperature combustion. However, emission factors describing the absorption cross section emitted per kg of fuel consumed (m(2)/kg) were of similar magnitude at 520 nm for the diverse combustion conditions investigated in this study. These results provide a link between biomass combustion conditions, emitted particle types, and their optical properties in fresh and processed plumes which can be of value for source apportionment and balanced mitigation of biomass combustion emissions from a climate and health perspective.
authors.affiliation: Division of Nuclear Physics, Lund University , Box 118, Lund SE-22100, Sweden.|Centre for Environmental and Climate Research, Lund University , Ecology Building, Lund SE-223 62, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Martinsson
authors.affiliation: Division of Nuclear Physics, Lund University , Box 118, Lund SE-22100, Sweden.|Ergonomics and Aerosol Technology, Lund University , Box 118, Lund SE-22100, Sweden.
authors.forename: A C
authors.initials: AC
authors.lastname: Eriksson
authors.affiliation: Department of Environmental Science, Aarhus University , Roskilde 4000, Denmark.
authors.forename: I Elbæk
authors.initials: IE
authors.lastname: Nielsen
authors.affiliation: Ergonomics and Aerosol Technology, Lund University , Box 118, Lund SE-22100, Sweden.
authors.forename: V Berg
authors.initials: VB
authors.lastname: Malmborg
authors.affiliation: Division of Nuclear Physics, Lund University , Box 118, Lund SE-22100, Sweden.|Centre for Environmental and Climate Research, Lund University , Ecology Building, Lund SE-223 62, Sweden.
authors.forename: E
authors.initials: E
authors.lastname: Ahlberg
authors.affiliation: Ergonomics and Aerosol Technology, Lund University , Box 118, Lund SE-22100, Sweden.
authors.forename: C
authors.initials: C
authors.lastname: Andersen
authors.affiliation: Thermochemical Energy Conversion Laboratory, Umeå University , Umeå SE-90187, Sweden.
authors.forename: R
authors.initials: R
authors.lastname: Lindgren
authors.affiliation: Thermochemical Energy Conversion Laboratory, Umeå University , Umeå SE-90187, Sweden.
authors.forename: R
authors.initials: R
authors.lastname: Nyström
authors.affiliation: Ergonomics and Aerosol Technology, Lund University , Box 118, Lund SE-22100, Sweden.
authors.forename: E Z
authors.initials: EZ
authors.lastname: Nordin
authors.affiliation: Department of Meteorology, Pennsylvania State University , University Park, Pennsylvania 16802-5013, United States.
authors.forename: W H
authors.initials: WH
authors.lastname: Brune
authors.affiliation: Division of Nuclear Physics, Lund University , Box 118, Lund SE-22100, Sweden.
authors.forename: B
authors.initials: B
authors.lastname: Svenningsson
authors.affiliation: Division of Nuclear Physics, Lund University , Box 118, Lund SE-22100, Sweden.
authors.forename: E
authors.initials: E
authors.lastname: Swietlicki
authors.affiliation: Thermochemical Energy Conversion Laboratory, Umeå University , Umeå SE-90187, Sweden.
authors.forename: C
authors.initials: C
authors.lastname: Boman
authors.affiliation: Ergonomics and Aerosol Technology, Lund University , Box 118, Lund SE-22100, Sweden.
authors.forename: J H
authors.initials: JH
authors.lastname: Pagels
mesh_terms: D000336:Aerosols / Q000032:analysis / Q000737:chemistry*; D018533:Biomass; D002244:Carbon / Q000737:chemistry; D006358:Hot Temperature; D008027:Light; D052638:Particulate Matter / Q000032:analysis / Q000737:chemistry*; D055668:Photochemical Processes; D059205:Renewable Energy; D053260:Soot / Q000032:analysis
chemical_list: D000336:Aerosols; D052638:Particulate Matter; D053260:Soot; D002244:Carbon