Light-Absorbing Brown Carbon Aerosol Constituents from Combustion of Indonesian Peat and Biomass.
Light-absorbing brown carbon (BrC) constituents of organic aerosol (OA) have been shown to significantly absorb ultraviolet (UV) and visible light and thus impact radiative forcing. However, molecular identification of the BrC constituents is still limited. In this study, we characterize BrC constituents at the molecular level in (i) aerosols emitted by combustion of peat, fern/leaf, and charcoal from Indonesia and (ii) ambient aerosols collected in Singapore during the 2015 haze episode. Aerosols were analyzed using ultra performance liquid chromatography instrument interfaced to a diode array detector and electrospray ionization high-resolution quadrupole time-of-flight mass spectrometer operated in the negative ion mode. In the laboratory-generated aerosols, we identified 41 compounds that can potentially absorb near-UV and visible wavelengths, such as oxygenated-conjugated compounds, nitroaromatics, and S-containing compounds. The sum of BrC constituents in peat, fern/leaf, and charcoal burning aerosols are 16%, 35%, and 28% of the OA mass, respectively, giving an average contribution of 24%. On average, the BrC constituents account for 0.4% of the ambient OA mass; however, large uncertainties in mass closure remain because of the lack of authentic standards. This study highlights the potential of light-absorbing BrC OA constituents from peat, fern/leaf, and charcoal burning and their importance in the atmosphere.
Earth Observatory of Singapore, Nanyang Technological University , Singapore 639798, Singapore.
Sri Hapsari
0000-0002-5715-9157
SH
Budisulistiorini
Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States.
Matthieu
M
Riva
Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States.
Michael
M
Williams
Earth Observatory of Singapore, Nanyang Technological University , Singapore 639798, Singapore.
Jing
J
Chen
Center for Southeast Asian Studies, Kyoto University , Kyoto 6068501, Japan.
Masayuki
M
Itoh
Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States.
Jason D
JD
Surratt
Earth Observatory of Singapore, Nanyang Technological University , Singapore 639798, Singapore.|Center for Southeast Asian Studies, Kyoto University , Kyoto 6068501, Japan.
Mikinori
M
Kuwata
D000336:Aerosols; D018533:Biomass; D002244:Carbon; D007214:Indonesia; D012987:Soil
D000336:Aerosols; D012987:Soil; D002244:Carbon