Mass size distribution of major monosaccharide anhydrides and mass contribution of biomass burning

Abstract. Aerosol hygroscopicity and black carbon (BC) properties were characterised during wintertime in Paris, one of the biggest European megacities. Hygroscopic growth factor (GF) distributions, characterised by distinct modes of more-hygroscopic background aerosol and non- or slightly hygroscopic aerosol of local (or regional) origin, revealed an increase of the relative contribution of the local sources compared to the background aerosol with decreasing particle size. BC particles in Paris were mainly originating from fresh traffic emissions, whereas biomass burning was only a minor contribution. The mass size distribution of the BC cores peaked on average at a BC core mass equivalent diameter of DMEV&approx;150 nm. The BC particles were moderately coated (Δcoat&approx;30 nm on average for BC cores with DMEV =160–260 nm) and an average mass absorption coefficient (MAC) of ~8.6 m2 g−1 at the wavelength λ = 880 nm was observed. Different time periods were selected to investigate the properties of BC particles as a function of source and air mass type. The traffic emissions were found to be non-hygroscopic (GF ≈ 1.0), and essentially all particles with a dry mobility diameter larger than D0 = 110 nm contained a BC core. BC from traffic emissions was further characterised by literally no coating (Δcoat &approx;2 nm), the smallest maximum of the BC core mass size distribution (DMEV&approx;100 nm) and the smallest MAC (~7.3 m2 g−1 at λ = 880 nm). The biomass burning aerosol was slightly more-hygroscopic than the traffic emissions (with a distinct slightly hygroscopic mode peaking at GF≈1.1–1.2). Furthermore, only a minor fraction (&leqslant;10%) of the slightly hygroscopic particles with GF&geqslant;1.1 (and D0 = 265 nm) contained a detectable BC core. The BC particles from biomass burning were found to have a medium coating thickness as well as slightly larger mean BC core sizes and MAC values compared to traffic emissions. The aerosol observed under the influence of aged air masses and air masses from Eastern Continental Europe was dominated by a more-hygroscopic mode peaking at GF≈1.6. Most particles (95%) with a D0 = 265 nm, in this mode, did not contain a detectable BC core. A significant fraction of the BC particles had a substantial coating with non-refractory aerosol components. MAC values of ~8.8 m2g−1 and ~8.3 m2 g−1 at λ = 880 nm and mass mean BC core diameters of 150 nm and 200 nm were observed for the aged and continental air mass types, respectively. The reason for the larger BC core sizes compared to the fresh emissions – transport effects or a different BC source – remains unclear. The dominant fraction of the BC-containing particles was found to have no or very little coating with non-refractory matter. The lack of coatings is consistent with the observation that the BC particles are non- or slightly hygroscopic, which makes them poor cloud condensation nuclei.

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Impact of vehicular emissions on the formation of fine particles in the Sao Paulo Metropolitan Area: a numerical study with the WRF-Chem model

Atmospheric Chemistry and Physics ◽

10.5194/acp-16-777-2016 ◽

2016 ◽

Vol 16 (2) ◽

pp. 777-797 ◽

Cited By ~ 29

Author(s):

A Vara-Vela ◽

M. F. Andrade ◽

P. Kumar ◽

R. Y. Ynoue ◽

A. G. Muñoz

Keyword(s):

Size Distribution ◽

Metropolitan Area ◽

Atmospheric Aerosols ◽

Fine Particles ◽

Sao Paulo ◽

Vehicular Emissions ◽

São Paulo ◽

Mass Size Distribution ◽

Mass Size ◽

The Impact

Abstract. The objective of this work is to evaluate the impact of vehicular emissions on the formation of fine particles (PM2.5; ≤  2.5 µm in diameter) in the Sao Paulo Metropolitan Area (SPMA) in Brazil, where ethanol is used intensively as a fuel in road vehicles. The Weather Research and Forecasting with Chemistry (WRF-Chem) model, which simulates feedbacks between meteorological variables and chemical species, is used as a photochemical modelling tool to describe the physico-chemical processes leading to the evolution of number and mass size distribution of particles through gas-to-particle conversion. A vehicular emission model based on statistical information of vehicular activity is applied to simulate vehicular emissions over the studied area. The simulation has been performed for a 1-month period (7 August–6 September 2012) to cover the availability of experimental data from the NUANCE-SPS (Narrowing the Uncertainties on Aerosol and Climate Changes in Sao Paulo State) project that aims to characterize emissions of atmospheric aerosols in the SPMA. The availability of experimental measurements of atmospheric aerosols and the application of the WRF-Chem model made it possible to represent some of the most important properties of fine particles in the SPMA such as the mass size distribution and chemical composition, besides allowing us to evaluate its formation potential through the gas-to-particle conversion processes. Results show that the emission of primary gases, mostly from vehicles, led to a production of secondary particles between 20 and 30 % in relation to the total mass concentration of PM2.5 in the downtown SPMA. Each of PM2.5 and primary natural aerosol (dust and sea salt) contributed with 40–50 % of the total PM10 (i.e. those ≤  10 µm in diameter) concentration. Over 40 % of the formation of fine particles, by mass, was due to the emission of hydrocarbons, mainly aromatics. Furthermore, an increase in the number of small particles impaired the ultraviolet radiation and induced a decrease in ozone formation. The ground-level O3 concentration decreased by about 2 % when the aerosol-radiation feedback is taken into account.

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Relation between particle number and mass size distribution in the diesel car exhaust

Journal of Aerosol Science ◽

10.1016/s0021-8502(99)80399-1 ◽

1999 ◽

Vol 30 ◽

pp. S777-S778 ◽

Cited By ~ 7

Author(s):

V.-M. Kerminen ◽

T. Mäkelä ◽

R. Hillamo ◽

L. Rantanen

Keyword(s):

Size Distribution ◽

Particle Number ◽

Mass Size Distribution ◽

Car Exhaust ◽

Mass Size

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Mass Size Distribution of Atmospheric Aerosol Particles with Nanosampler Cascade Impactor in Jinju City

Journal of Environmental Science International ◽

10.5322/jesi.2015.24.5.679 ◽

2015 ◽

Vol 24 (5) ◽

pp. 679-687 ◽

Cited By ~ 1

Author(s):

Jeong-Ho Park ◽

Min-Jae Jang ◽

Hyoung-Kab Kim

Keyword(s):

Size Distribution ◽

Atmospheric Aerosol ◽

Aerosol Particles ◽

Cascade Impactor ◽

Mass Size Distribution ◽

Atmospheric Aerosol Particles ◽

Mass Size

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Estimation of Mass Size Distribution of Atmospheric Aerosols Using Real-Time Aerosol Measuring Instruments

The Journal of Korean Association for Particle and Aerosol Research ◽

10.11629/jpaar.2013.9.2.039 ◽

2013 ◽

Vol 9 (2) ◽

pp. 39-50

Author(s):

Jun-Ho Ji ◽

◽

Gwi-Nam Bae

Keyword(s):

Size Distribution ◽

Real Time ◽

Atmospheric Aerosols ◽

Measuring Instruments ◽

Mass Size Distribution ◽

Mass Size

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Black carbon physical properties and mixing state in the European megacity Paris

Atmospheric Chemistry and Physics ◽

10.5194/acp-13-5831-2013 ◽

2013 ◽

Vol 13 (11) ◽

pp. 5831-5856 ◽

Cited By ~ 104

Author(s):

M. Laborde ◽

M. Crippa ◽

T. Tritscher ◽

Z. Jurányi ◽

P. F. Decarlo ◽

...

Keyword(s):

Size Distribution ◽

Biomass Burning ◽

Coating Thickness ◽

Traffic Emissions ◽

Core Mass ◽

Air Mass ◽

Air Masses ◽

Mass Size ◽

A Minor ◽

Wet Removal

Abstract. Aerosol hygroscopicity and refractory black carbon (rBC) properties were characterised during wintertime at a suburban site in Paris, one of the biggest European cities. Hygroscopic growth factor (GF) frequency distributions, characterised by distinct modes of more-hygroscopic background aerosol and non- or slightly hygroscopic aerosol of local (or regional) origin, revealed an increase of the relative contribution of the local sources compared to the background aerosol with decreasing particle size. BC-containing particles in Paris were mainly originating from fresh traffic emissions, whereas biomass burning only gave a minor contribution. The mass size distribution of the rBC cores peaked on average at an rBC core mass equivalent diameter of DMEV ~ 150 nm. The BC-containing particles were moderately coated (coating thickness Δcoat ~ 33 nm on average for rBC cores with DMEV = 180–280 nm) and an average mass absorption coefficient (MAC) of ~ 8.6 m2 g−1 at the wavelength λ = 880 nm was observed. Different time periods were selected to investigate the properties of BC-containing particles as a function of source and air mass type. The traffic emissions were found to be non-hygroscopic (GF ≈ 1.0), and essentially all particles with a dry mobility diameter (D0) larger than D0 = 110 nm contained an rBC core. rBC from traffic emissions was further observed to be uncoated within experimental uncertainty (Δcoat ~ 2 nm ± 10 nm), to have the smallest BC core sizes (maximum of the rBC core mass size distribution at DMEV ~ 100 nm) and to have the smallest MAC (~ 7.3 m2g−1 at λ = 880 nm). The biomass burning aerosol was slightly more hygroscopic than the traffic emissions (with a distinct slightly-hygroscopic mode peaking at GF ≈ 1.1–1.2). Furthermore, only a minor fraction (&leq; 10%) of the slightly-hygroscopic particles with 1.1 &leq; GF &leq; 1.2 (and D0 = 265 nm) contained a detectable rBC core. The BC-containing particles from biomass burning were found to have a medium coating thickness as well as slightly larger mean rBC core sizes and MAC values compared to traffic emissions. The aerosol observed under the influence of aged air masses and air masses from Eastern Continental Europe was dominated by a~more-hygroscopic mode peaking at GF ≈ 1.6. Most particles (95%), in the more-hygroscopic mode at D0 = 265 nm, did not contain a detectable rBC core. A significant fraction of the BC-containing particles had a substantial coating with non-refractory aerosol components. MAC values of ~ 8.8 m2g−1 and ~ 8.3 m2g−1 at λ = 880 nm and mass mean rBC core diameters of 150 nm and 200 nm were observed for the aged and continental air mass types, respectively. The reason for the larger rBC core sizes compared to the fresh emissions – transport effects or a different rBC source – remains unclear. The dominant fraction of the BC-containing particles was found to have no or very little coating with non-refractory matter. The lack of coatings is consistent with the observation that the BC-containing particles are non- or slightly-hygroscopic, which makes them poor cloud condensation nuclei. It can therefore be expected that wet removal through nucleation scavenging is inefficient for fresh BC-containing particles in urban plumes. The mixing-state-specific cloud droplet activation behaviour of BC-containing particles including the effects of atmospheric aging processes should be considered in global simulations of atmospheric BC, as the wet removal efficiency remains a major source of uncertainty in its life-cycle.

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Role of black carbon mass size distribution in the direct aerosol radiative forcing

Atmospheric Chemistry and Physics ◽

10.5194/acp-19-13175-2019 ◽

2019 ◽

Vol 19 (20) ◽

pp. 13175-13188 ◽

Cited By ~ 2

Author(s):

Gang Zhao ◽

Jiangchuan Tao ◽

Ye Kuang ◽

Chuanyang Shen ◽

Yingli Yu ◽

...

Keyword(s):

Size Distribution ◽

Black Carbon ◽

Radiative Forcing ◽

Climate Models ◽

Radiative Effects ◽

Aerosol Radiative Forcing ◽

Mass Size Distribution ◽

Mass Size ◽

Mixing States ◽

Aerosol Radiative

Abstract. Large uncertainties exist when estimating radiative effects of ambient black carbon (BC) aerosol. Previous studies about the BC aerosol radiative forcing mainly focus on the BC aerosols' mass concentrations and mixing states, while the effects of BC mass size distribution (BCMSD) were not well considered. In this paper, we developed a method of measuring the BCMSD by using a differential mobility analyzer in tandem with an Aethalometer. A comprehensive method of multiple charging corrections was proposed and implemented in measuring the BCMSD. Good agreement was obtained between the BC mass concentration integrated from this system and that measured in the bulk phase, demonstrating the reliability of our proposed method. Characteristics of the BCMSD and corresponding radiative effects were studied based on a field measurement campaign conducted in the North China Plain by using our own measurement system. Results showed that the BCMSD had two modes and the mean peak diameters of the modes were 150 and 503 nm. The BCMSD of the coarser mode varied significantly under different pollution conditions with peak diameter varying between 430 and 580 nm, which gave rise to significant variation in aerosol bulk optical properties. The direct aerosol radiative forcing was estimated to vary by 8.45 % for different measured BCMSDs of the coarser mode, which shared the same magnitude with the variation associated with assuming different aerosol mixing states (10.5 %). Our study reveals that the BCMSD as well as its mixing state in estimating the direct aerosol radiative forcing matters. Knowledge of the BCMSD should be fully considered in climate models.

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Assessment of Air Quality in School Environments in Hanoi, Vietnam: A Focus on Mass-Size Distribution and Elemental Composition of Indoor-Outdoor Ultrafine/Fine/Coarse Particles

Atmosphere ◽

10.3390/atmos11050519 ◽

2020 ◽

Vol 11 (5) ◽

pp. 519

Author(s):

Trinh Dinh Tran ◽

Phuong Minh Nguyen ◽

Dung Trung Nghiem ◽

Tuyen Huu Le ◽

Minh Binh Tu ◽

...

Keyword(s):

Trace Elements ◽

Elemental Composition ◽

Size Distribution ◽

World Health ◽

Emission Sources ◽

Mass Size Distribution ◽

Minor Elements ◽

Mass Size ◽

Pm2.5 And Pm10 ◽

Indoor And Outdoor

Indoor and outdoor ultrafine, accumulation mode, and coarse fractions collected at two preschools (S1 and S2) in Hanoi capital, Vietnam were characterized in terms of mass-size distribution and elemental composition to identify major emission sources. The sampling campaigns were performed simultaneously indoors and outdoors over four consecutive weeks at each school. Indoor average concentrations of CO2 and CO at both schools were below the limit values recommended by American Society of Heating, Refrigerating and Air-Conditioning Engineers (1000 ppm for CO2) and World Health Organization (7 mg/m3 for CO). Indoor concentrations of PM2.5 and PM10 at S1 and S2 were strongly influenced by the presence of children and their activities indoors. The indoor average concentrations of PM2.5 and PM10 were 49.4 µg/m3 and 59.7 µg/m3 at S1, while those values at S2 were 7.9 and 10.8 µg/m3, respectively. Mass-size distribution of indoor and outdoor particles presented similar patterns, in which ultrafine particles accounted for around 15–20% wt/wt while fine particles (PM2.5) made up almost 80% wt/wt of PM10. PM2.5–10 did not display regular shapes while smaller factions tended to aggregate to form clusters with fine structures. Oxygen (O) was the most abundant element in all fractions, followed by carbon (C) for indoor and outdoor particles. O accounted for 36.2% (PM0.5–1) to 42.4% wt/wt (PM0.1) of indoor particles, while those figures for C were in the range of 14.5% (for PM0.1) to 18.1% (for PM1–2.5). Apart from O and C, mass proportion of other major and minor elements (Al, Ca, Cr, Fe , K, Mg, Si, Ti) could make up to 50%, whereas trace elements (As, Bi, Cd, Co, Cr, Cu, La, Mn, Mo, Ni, Pb, Rb, Sb, Se, Sn, Sr, and Zn) accounted for less than 0.5% of indoor and outdoor airborne particles. There were no significant indoor emission sources of trace and minor elements. Traffic significantly contributed to major and trace elements at S1 and S2.

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