Assessment of biomass burning and fossil fuel contribution to black carbon concentrations in Delhi during winter

Abstract. The Aethalometer model been used widely for estimating the contributions of fossil fuel emissions and biomass burning to equivalent black carbon (eBC). The calculation is based on measured absorption Ångström exponents (αabs). The interpretation αabs is ambiguous since it is well-known that it not only depends on the dominant absorber but also on the size and internal structure of the particles, core size and shell thickness. In this work the uncertainties of the Aethalometer-model-derived apparent fractions of absorption by eBC from fossil fuel and biomass burning are evaluated with a core-shell Mie model. Biomass-burning fractions (BB(%)) were calculated for pure and coated single BC particles, for lognormal unimodal and bimodal size distributions of BC cores coated with ammonium sulfate, a scattering-only material. BB(%) was very seldom 0 % even though BC was the only absorbing material in the simulations. The shape of size distribution plays an important role. Narrow size distributions result in higher αabs and BB(%) values than wide size distributions. The sensitivity of αabs and BB(%) to variations in shell volume fractions is the highest for accumulation mode particles. This is important because that is where the largest aerosol mass is. For the interpretation of absorption Ångström exponents it would be very good to measure BC size distributions and shell thicknesses together with the wavelength dependency of absorption.

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Supplementary material to "Measurement report: Quantifying source contribution and radiative forcing of fossil fuel and biomass burning black carbon aerosol in the southeastern margin of Tibetan Plateau"

10.5194/acp-2020-408-supplement ◽

2020 ◽

Author(s):

Huikun Liu ◽

Qiyuan Wang ◽

Li Xing ◽

Yong Zhang ◽

Ting Zhang ◽

...

Keyword(s):

Tibetan Plateau ◽

Black Carbon ◽

Biomass Burning ◽

Radiative Forcing ◽

Fossil Fuel ◽

Source Contribution ◽

Southeastern Margin ◽

Supplementary Material ◽

Black Carbon Aerosol

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Spatio-temporal trends and source apportionment of fossil fuel and biomass burning black carbon (BC) in the Los Angeles Basin

The Science of The Total Environment ◽

10.1016/j.scitotenv.2018.06.022 ◽

2018 ◽

Vol 640-641 ◽

pp. 1231-1240 ◽

Cited By ~ 24

Author(s):

Amirhosein Mousavi ◽

Mohammad H. Sowlat ◽

Sina Hasheminassab ◽

Andrea Polidori ◽

Constantinos Sioutas

Keyword(s):

Los Angeles ◽

Black Carbon ◽

Source Apportionment ◽

Biomass Burning ◽

Fossil Fuel ◽

Temporal Trends ◽

Los Angeles Basin ◽

Spatio Temporal

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Source apportionment of black carbon aerosols from light absorption observation and source-oriented modeling: an implication in a coastal city in China

Atmospheric Chemistry and Physics ◽

10.5194/acp-20-14419-2020 ◽

2020 ◽

Vol 20 (22) ◽

pp. 14419-14435

Author(s):

Junjun Deng ◽

Hao Guo ◽

Hongliang Zhang ◽

Jialei Zhu ◽

Xin Wang ◽

...

Keyword(s):

Climate Change ◽

Black Carbon ◽

Source Apportionment ◽

Biomass Burning ◽

Light Absorption ◽

Fossil Fuel ◽

Central China ◽

Fossil Fuel Combustion ◽

East Central ◽

Coastal City

Abstract. Black carbon (BC) is the most important light-absorbing aerosol in the atmosphere. However, sources of atmospheric BC aerosols are largely uncertain, making it difficult to assess its influence on radiative forcing and climate change. In this study, year-round light-absorption observations were conducted during 2014 using an aethalometer in Xiamen, a coastal city in Southeast China. Source apportionment of BC was performed and temporal variations in BC sources were characterized based on both light absorption measurements and a source-oriented air quality model. The annual average concentrations of BC from fossil fuel (BCff) and biomass burning (BCbb) by the aethalometer method were 2932 ± 1444 ng m−3 and 1340 ± 542 ng m−3, contributing 66.7 % and 33.3 % to total BC, respectively. A sensitivity analysis was performed with different absorption Ångström exponent (AAE) values of fossil fuel combustion (αff) and biomass burning (αbb), suggesting that the aethalometer method was more sensitive to changes in αbb than αff. BCbb contribution exhibited a clear diurnal cycle, with the highest level (37.9 %) in the evening rush hour and a seasonal pattern with the maximum (39.9 %) in winter. Conditional probability function (CPF) analysis revealed the large biomass-burning contributions were accompanied by east-northeasterly and northerly winds. Backward trajectory indicated that air masses from North and East–Central China were associated with larger biomass-burning contributions. Potential source contribution function (PSCF) and concentration-weighted trajectory (CWT) suggested that North and East–Central China and Southeast Asia were potential sources of both BCff and BCbb. The source-oriented modeling results showed that transportation, residential and open biomass burning accounting for 45.3 %, 30.1 % and 17.6 % were the major BC sources. Among the three fuel catalogs, liquid fossil fuel (46.5 %) was the largest source, followed by biomass burning (32.6 %) and coal combustion (20.9 %). Source contributions of fossil fuel combustion and biomass burning identified by the source-oriented model were 67.4 % and 32.6 %, respectively, close to those obtained by the aethalometer method. The findings provide solid support for controlling fossil fuel sources to limit the impacts of BC on climate change and environmental degradation in the relatively clean region in China.

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Measurement report: Determination of Black Carbon concentration in PM<sub>2.5</sub> fraction by Multi-wavelength absorption black carbon instrument (MABI)

10.5194/acp-2021-766 ◽

2021 ◽

Author(s):

Anna Ryś ◽

Lucyna Samek

Keyword(s):

Seasonal Variation ◽

Black Carbon ◽

Biomass Burning ◽

Fossil Fuel ◽

Environmental Sciences ◽

Absorption Coefficients ◽

Multi Wavelength ◽

Wavelength Absorption ◽

The Mean

Abstract. The evaluation of black carbon (BC) sources is very important, especially in environmental sciences. This study shows how the contributions of biomass burning and fossil fuel/traffic to PM2.5 mass can be assessed. MABI was used for this purpose and gave the possibility to measure the transmission of light at different wavelengths. Absorption coefficients were calculated from measurements data and recalculated for concentrations of eBC. The samples of PM2.5 fraction were collected from February 1, 2020 to March 27, 2021 every third day in Krakow, Poland (50°04' N, 19°54'47" E). The concentrations of equivalent BC (eBC) from fossil fuel/traffic and biomass burning were in the range 0.82–11.64 μg m−3) and 0.007–0.84 μg m−3, respectively. At the same time, PM2.5 concentrations varied from 3.14 to 55.24 μg m−3. It means that about 18 % of PM2.5 mass belongs to eBC and 11.3 % of this value comes from biomass burning. The eBC contribution is the significant part of PM2.5 mass and we observed seasonal variation of the eBC concentration during the year with the peak in winter. The contribution of biomass burning to PM2.5 mass is more stable during the whole year. The eBC concentration during workdays is a bit higher than during weekend days but biomass burning is similar for both days (work and weekend taken as the mean for the whole period).

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Ambient measurements and source apportionment of fossil fuel and biomass burning black carbon in Ontario

Atmospheric Environment ◽

10.1016/j.atmosenv.2017.04.034 ◽

2017 ◽

Vol 161 ◽

pp. 34-47 ◽

Cited By ~ 57

Author(s):

R.M. Healy ◽

U. Sofowote ◽

Y. Su ◽

J. Debosz ◽

M. Noble ◽

...

Keyword(s):

Black Carbon ◽

Source Apportionment ◽

Biomass Burning ◽

Fossil Fuel ◽

Ambient Measurements

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The contribution of black carbon to global ice nucleating particle concentrations relevant to mixed-phase clouds

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2001674117 ◽

2020 ◽

Vol 117 (37) ◽

pp. 22705-22711

Author(s):

Gregory P. Schill ◽

Paul J. DeMott ◽

Ethan W. Emerson ◽

Anne Marie C. Rauker ◽

John K. Kodros ◽

...

Keyword(s):

Black Carbon ◽

Biomass Burning ◽

Fossil Fuel ◽

Supercooled Liquid ◽

Mixed Phase ◽

Radiative Properties ◽

Prescribed Burns ◽

Earth’S Climate ◽

Mixed Phase Clouds ◽

Fossil Fuel Emissions

Black carbon (BC) aerosol plays an important role in the Earth’s climate system because it absorbs solar radiation and therefore potentially warms the climate; however, BC can also act as a seed for cloud particles, which may offset much of its warming potential. If BC acts as an ice nucleating particle (INP), BC could affect the lifetime, albedo, and radiative properties of clouds containing both supercooled liquid water droplets and ice particles (mixed-phase clouds). Over 40% of global BC emissions are from biomass burning; however, the ability of biomass burning BC to act as an INP in mixed-phase cloud conditions is almost entirely unconstrained. To provide these observational constraints, we measured the contribution of BC to INP concentrations ([INP]) in real-world prescribed burns and wildfires. We found that BC contributes, at most, 10% to [INP] during these burns. From this, we developed a parameterization for biomass burning BC and combined it with a BC parameterization previously used for fossil fuel emissions. Applying these parameterizations to global model output, we find that the contribution of BC to potential [INP] relevant to mixed-phase clouds is ∼5% on a global average.

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