Influence of relative humidity and aging on the optical properties of organic aerosols from burning African biomass fuels DOI Creative Commons
Megan M. McRee, Vaios Moschos, Marc N. Fiddler

et al.

Aerosol Science and Technology, Journal Year: 2024, Volume and Issue: unknown, P. 1 - 23

Published: Oct. 11, 2024

Biomass burning (BB) is a major source of atmospheric fine carbonaceous aerosols, which play significant, yet uncertain, role in modulating the Earth's radiation balance. However, accurately representing their optical properties climate models remains challenging due to factors such as particle size, mixing state, combustion type, chemical composition, aging processes, and relative humidity (RH). In our study, we investigated BB organic-rich aerosols generated from smoldering sub-Saharan African biomass fuels. Fuel samples were collected Africa laboratory. We quantified key parameters, including mass cross-sections for extinction (2.04 ± 0.32 − 15.5 2.48 m2/g), absorption (0.04 0.01–0.3 0.1 scattering (1.9 0.68–15.3 5.5 m2/g). Wavelength-dependent used determine Ångström exponents. The single albedo these ranged 0.8 0.03 1.0 0.04 observed wavelength-dependent behavior. Extinction emission determined at wavelength 550 nm, with values ranging 42 5 293 32 m2/kg. Notably, exhibited fuel-type dependence, differences between hardwood other fuels, grass animal dung. Aging increased while had opposite effect across all Nitrate radical oxidation, both photo dark conditions, also influenced properties. findings are expected close gap understanding aerosol emissions one least studied regions world – providing information air quality region.

Language: Английский

New insights into the molecular characteristics-dependent light absorption variation of water-soluble organic matter in biomass burning smoke DOI
Weifeng Chen, Huiying Zhang,

Shiming Xu

et al.

Atmospheric Research, Journal Year: 2025, Volume and Issue: unknown, P. 107951 - 107951

Published: Jan. 1, 2025

Language: Английский

Citations

0
Measurement report: Optical and structural properties of atmospheric water-soluble organic carbon in China – insights from multi-site spectroscopic measurements DOI Creative Commons
Haibiao Chen, Caiqing Yan,

Liubin Huang

et al.

Atmospheric chemistry and physics, Journal Year: 2025, Volume and Issue: 25(6), P. 3647 - 3667

Published: March 27, 2025

Abstract. To understand the spatial variation of optical and structural properties water-soluble brown carbon its influencing factors in China, light absorption, fluorescence, Fourier transform infrared (FTIR) spectrum organic (WSOC) different regions China are measured following same analytical methods. The average absorption coefficients mass efficiencies WSOC at 365 nm (Abs365 MAE365) rank from high to low as northwest > southwest north east regional site, with higher values northern than southern sites inland areas coastal areas. resolved by spectra-based positive matrix factorization model abundance aromatic O−H C=C functional groups determined FTIR both indicate that compounds significant light-absorbing substances have a impact on fluorophores. Multiple linear regression analysis shows fluorophores identified fluorescence spectra combined parallel factor (PARAFAC) contribute about 62 %–93 % all sites, which humic-like substance (HULIS) contributes most, especially highly oxygenated HULIS (29 %–50 %) long emission wavelengths. Combustion source emissions atmospheric chemical processes impacts some sites. Moreover, relative humidity (RH) can also affect MAE365 WSOC, decreasing increase RH when RH<60 remaining relatively unchanged RH>60 %. Taken together, this study promotes better understanding heterogeneity their China.

Language: Английский

Citations

0
Measurement Report: Optical and structural properties of atmospheric water-soluble organic carbon in China: Insights from multi-site spectroscopic measurements DOI Creative Commons
Haibiao Chen, Caiqing Yan,

Liubin Huang

et al.

Published: Aug. 20, 2024

Abstract. To understand the spatial variation of optical and structural properties water-soluble brown carbon its influencing factors in China, light absorption, fluorescence, Fourier transform infrared (FTIR) spectrum organic (WSOC) different regions China are measured following same analytical methods. The average absorption coefficients mass efficiencies WSOC at 365 nm (Abs365 MAE365) rank from high to low as northwest > southwest north east regional site, with higher values Northern than Southern sites, inland areas coastal areas. resolved by positive matrix factorization model combined spectra abundant aromatic O-H C=C functional groups determined FTIR both indicate that compounds important light-absorbing substances WSOC, which also have a significant impact on fluorophores. Multiple linear regression analysis shows identified fluorophores fluorescence parallel factor contribute about 62–93 % all humic-like substance (HULIS) contributes most, especially highly‑oxygenated HULIS (29 %–50 %) long emission wavelengths. Combustion source emissions atmospheric chemical processes impacts some sites. Moreover, relative humidity (RH) can affect MAE365 decreasing increase RH when < 60 remaining relatively unchanged %. Taken together, this study promotes better understanding heterogeneity their China.

Language: Английский

Citations

1
Influence of relative humidity and aging on the optical properties of organic aerosols from burning African biomass fuels DOI Creative Commons
Megan M. McRee, Vaios Moschos, Marc N. Fiddler

et al.

Aerosol Science and Technology, Journal Year: 2024, Volume and Issue: unknown, P. 1 - 23

Published: Oct. 11, 2024

Biomass burning (BB) is a major source of atmospheric fine carbonaceous aerosols, which play significant, yet uncertain, role in modulating the Earth's radiation balance. However, accurately representing their optical properties climate models remains challenging due to factors such as particle size, mixing state, combustion type, chemical composition, aging processes, and relative humidity (RH). In our study, we investigated BB organic-rich aerosols generated from smoldering sub-Saharan African biomass fuels. Fuel samples were collected Africa laboratory. We quantified key parameters, including mass cross-sections for extinction (2.04 ± 0.32 − 15.5 2.48 m2/g), absorption (0.04 0.01–0.3 0.1 scattering (1.9 0.68–15.3 5.5 m2/g). Wavelength-dependent used determine Ångström exponents. The single albedo these ranged 0.8 0.03 1.0 0.04 observed wavelength-dependent behavior. Extinction emission determined at wavelength 550 nm, with values ranging 42 5 293 32 m2/kg. Notably, exhibited fuel-type dependence, differences between hardwood other fuels, grass animal dung. Aging increased while had opposite effect across all Nitrate radical oxidation, both photo dark conditions, also influenced properties. findings are expected close gap understanding aerosol emissions one least studied regions world – providing information air quality region.

Language: Английский

Citations

1