Natural and human-induced biomass burning in Africa: an important source for volatile organic compounds in the troposphere

Abstract. Toluene and benzene are used for assessing the ability to measure disjunct eddy covariance (DEC) fluxes of Volatile Organic Compounds (VOC) using Proton Transfer Reaction Mass Spectrometry (PTR-MS) on aircraft. Statistically significant correlation between vertical wind speed and mixing ratios suggests that airborne VOC eddy covariance (EC) flux measurements using PTR-MS are feasible. City-average midday toluene and benzene fluxes are calculated to be on the order of 15.5±4.0 mg/m2/h and 4.7±2.3 mg/m2/h respectively. These values argue for an underestimation of toluene and benzene emissions in current inventories used for the Mexico City Metropolitan Area (MCMA). Wavelet analysis of instantaneous toluene and benzene measurements during city overpasses is tested as a tool to assess surface emission heterogeneity. High toluene to benzene flux ratios above an industrial district (e.g. 10–15) including the International airport (e.g. 3–5) and a mean flux (concentration) ratio of 3.2±0.5 (3.9±0.3) across Mexico City indicate that evaporative fuel and industrial emissions play an important role for the prevalence of aromatic compounds. Based on a tracer model, which was constrained by BTEX (Benzene/Toluene/Ethylbenzene/m,p,o-Xylenes) compound concentration ratios, the fuel marker methyl-tertiary-butyl-ether (MTBE) and the biomass burning marker acetonitrile (CH3CN), we show that a combination of industrial, evaporative fuel, and exhaust emissions account for >90% of all BTEX sources. Our observations suggest that biomass burning emissions play a minor role for the abundance of BTEX compounds (0–10%) in the MCMA.

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Source Profiles of Volatile Organic Compounds from Biomass Burning in Yangtze River Delta, China

Aerosol and Air Quality Research ◽

10.4209/aaqr.2013.05.0174 ◽

2014 ◽

Vol 14 (3) ◽

pp. 818-828 ◽

Cited By ~ 36

Author(s):

Hongli Wang ◽

Shengrong Lou ◽

Cheng Huang ◽

Liping Qiao ◽

Xibin Tang ◽

...

Keyword(s):

Volatile Organic Compounds ◽

Organic Compounds ◽

Biomass Burning ◽

Yangtze River ◽

Yangtze River Delta ◽

River Delta ◽

Source Profiles ◽

Volatile Organic

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Measurements of volatile organic compounds in the middle of Central East China during Mount Tai Experiment 2006 (MTX2006): observation of regional background and impact of biomass burning

Atmospheric Chemistry and Physics ◽

10.5194/acp-10-1269-2010 ◽

2010 ◽

Vol 10 (3) ◽

pp. 1269-1285 ◽

Cited By ~ 36

Author(s):

J. Suthawaree ◽

S. Kato ◽

K. Okuzawa ◽

Y. Kanaya ◽

P. Pochanart ◽

...

Keyword(s):

Volatile Organic Compounds ◽

Organic Compounds ◽

Biomass Burning ◽

Primary Source ◽

Temporal Variations ◽

East China ◽

Boundary Layer Height ◽

Mixing Ratios ◽

Regional Background ◽

Volatile Organic

Abstract. The measurement of volatile organic compounds (VOCs) was carried out at the summit of Mount Tai, located in the center of the Central East China (CEC) region, in June 2006 as part of the Mount Tai Experiment 2006 (MTX2006), which focused on the ozone and aerosol chemistry in the region. Temporal variations of simple VOCs between 2 June and 28 June revealed the characteristics of an aged air mass with minimum local influence. A comparison of VOCs observed at Mount Tai with other Chinese sites revealed relatively similar VOC levels to remote sites and, as expected, a lower level compared to more polluted sites. However, relatively high acetylene and benzene levels at Mount Tai were evidently indicated from comparison with normalized VOC profile by ethane suggested for Beijing. Owing to a shift in boundary layer height, we observed considerable differences between daytime and nighttime VOC mixing ratios. This suggests that the site potentially has a very useful characteristic of being able to measure regional polluted air and the free troposphere regional background air quality. Influence of emissions from biomass burning in the region was evidently found to be extensive during the first half of the campaign (2–15 June), using fire spot data coupling with backward trajectory analysis. Agricultural residue burning was suggested as the primary source of emissions elucidated by the slope of the correlation plot between CH3Cl and CO obtained during the first half of the campaign.

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The role of semi-volatile organic compounds in the mesoscale evolution of biomass burning aerosol: a modelling case study of the 2010 mega-fire event in Russia

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-15-9107-2015 ◽

2015 ◽

Vol 15 (6) ◽

pp. 9107-9172 ◽

Cited By ~ 1

Author(s):

I. B. Konovalov ◽

M. Beekmann ◽

E. V. Berezin ◽

H. Petetin ◽

T. Mielonen ◽

...

Keyword(s):

Air Pollution ◽

Volatile Organic Compounds ◽

Organic Compounds ◽

Biomass Burning ◽

Organic Aerosol ◽

Conventional Approach ◽

Pollution Monitoring ◽

Basis Set ◽

Aerosol Emission ◽

Volatile Organic

Abstract. Chemistry transport models (CTMs) are an indispensable tool for studying and predicting atmospheric and climate effects associated with carbonaceous aerosol from open biomass burning (BB); this type of aerosol is known to contribute significantly to both global radiative forcing and to episodes of air pollution in regions affected by wildfires. Improving model performance requires systematic comparison of simulation results with measurements of BB aerosol and elucidating possible reasons for discrepancies between them, which, "by default", are frequently attributed in the literature to uncertainties in emission data. Based on published laboratory data regarding atmospheric evolution of BB aerosol and by using the volatility basis set (VBS) approach to organic aerosol modeling along with a "conventional" approach, we examined the importance of taking gas-particle partitioning and oxidation of semi-volatile organic compounds (SVOCs) into account in simulations of the mesoscale evolution of smoke plumes from intense wildfires that occurred in western Russia in 2010. BB emissions of primary aerosol components were constrained with the PM10 and CO data from the air pollution monitoring network in the Moscow region. The results of the simulations performed with the CHIMERE CTM were evaluated by considering, in particular, the ratio of smoke-related enhancements in PM10 and CO concentrations (ΔPM10 and ΔCO) measured in Finland (in the city of Kuopio), nearly 1000 km downstream of the fire emission sources. It is found that while the conventional approach (disregarding oxidation of SVOCs and assuming organic aerosol material to be non-volatile) strongly underestimates values of ΔPM10/ΔCO observed in Kuopio (by almost a factor of two), the VBS approach is capable to bring the simulations to a reasonable agreement with the ground measurements both in Moscow and in Kuopio. Using the VBS instead of the conventional approach is also found to result in a major improvement of the agreement of simulations and satellite measurements of aerosol optical depth, as well as in considerable changes in predicted aerosol composition and top-down BB aerosol emission estimates derived from AOD measurements.

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Observations of volatile organic compounds during ARCTAS – Part 1: Biomass burning emissions and plume enhancements

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-11-14127-2011 ◽

2011 ◽

Vol 11 (5) ◽

pp. 14127-14182 ◽

Cited By ~ 1

Author(s):

R. S. Hornbrook ◽

D. R. Blake ◽

G. S. Diskin ◽

H. E. Fuelberg ◽

S. Meinardi ◽

...

Keyword(s):

Volatile Organic Compounds ◽

Organic Compounds ◽

Biomass Burning ◽

Time Of Day ◽

The Arctic ◽

Fire Emissions ◽

Mixing Ratios ◽

Significant Difference ◽

Volatile Organic ◽

Good Agreement

Abstract. Mixing ratios of a large number of volatile organic compounds (VOCs) were observed by the Trace Organic Gas Analyzer (TOGA) on board the NASA DC-8 as part of the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) field campaign. Many of these VOCs were observed concurrently by one or both of two other VOC measurement techniques on board the DC-8: proton-transfer-reaction mass spectrometry (PTR-MS) and whole air canister sampling (WAS). A comparison of these measurements to the data from TOGA indicates good agreement for the majority of co-measured VOCs. The ARCTAS study, which included both spring and summer deployments, provided opportunities to sample a large number of biomass burning (BB) plumes with origins in Asia, California and Central Canada, ranging from very recent emissions to plumes aged one week or more. For this analysis, identified BB plumes were grouped by flight, source region and, in some cases, time of day, generating 40 individual plume groups, each consisting of one or more BB plume interceptions. Normalized excess mixing ratios (EMRs) to CO were determined for each of the 40 plume groups for up to 19 different VOCs or VOC groups, many of which show significant variability, even within relatively fresh plumes. This variability demonstrates the importance of assessing BB plumes both regionally and temporally, as emissions can vary from region to region, and even within a fire over time. Comparisons with literature confirm that variability of EMRs to CO over an order of magnitude for many VOCs is consistent with previous observations. However, this variability is often diluted in the literature when individual observations are averaged to generate an overall regional EMR from a particular study. Previous studies give the impression that emission ratios are generally consistent within a given region, and this is not necessarily the case, as our results show. For some VOCs, earlier assumptions may lead to significant under-prediction of emissions in fire emissions inventories. Notably, though variable between plumes, observed EMRs of individual light alkanes are highly correlated within BB emissions. Using the NCAR master mechanism chemical box model initialized with concentrations based on two observed scenarios, i.e., fresh Canadian BB and fresh Californian BB, both plumes are expected to experience primarily decreases in oxygenated VOCs during the first 2.5 days, such that any production in the plumes of these compounds is less than the chemical loss. Comparisons of the modeled EMRs to the observed EMRs from BB plumes estimated to be three days in age or less indicate overall good agreement and, for most compounds, no significant difference between BB plumes in these two regions.

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Measurement report: Source apportionment of volatile organic compounds at the remote high-altitude Maïdo observatory

Atmospheric Chemistry and Physics ◽

10.5194/acp-21-12965-2021 ◽

2021 ◽

Vol 21 (17) ◽

pp. 12965-12988

Author(s):

Bert Verreyken ◽

Crist Amelynck ◽

Niels Schoon ◽

Jean-François Müller ◽

Jérôme Brioude ◽

...

Keyword(s):

Volatile Organic Compounds ◽

Source Apportionment ◽

Organic Compounds ◽

Biomass Burning ◽

Free Troposphere ◽

La Réunion ◽

Air Masses ◽

Mixing Ratios ◽

Volatile Organic ◽

The Impact

Abstract. We present a source apportionment study of a near-continuous 2-year dataset of volatile organic compounds (VOCs), recorded between October 2017 and November 2019 with a quadrupole-based high-sensitivity proton-transfer-reaction mass-spectrometry (hs-PTR-MS) instrument deployed at the Maïdo observatory (21.1∘ S, 55.4∘ E, 2160 m altitude). The observatory is located on La Réunion island in the southwest Indian Ocean. We discuss seasonal and diel profiles of six key VOC species unequivocally linked to specific sources – acetonitrile (CH3CN), isoprene (C5H8), isoprene oxidation products (Iox), benzene (C6H6), C8-aromatic compounds (C8H10), and dimethyl sulfide (DMS). The data are analyzed using the positive matrix factorization (PMF) method and back-trajectory calculations based on the Lagrangian mesoscale transport model FLEXPART-AROME to identify the impact of different sources on air masses sampled at the observatory. As opposed to the biomass burning tracer CH3CN, which does not exhibit a typical diel pattern consistently throughout the dataset, we identify pronounced diel profiles with a daytime maximum for the biogenic (C5H8 and Iox) and anthropogenic (C6H6, C8H10) tracers. The marine tracer DMS generally displays a daytime maximum except for the austral winter when the difference between daytime and nighttime mixing ratios vanishes. Four factors were identified by the PMF: background/biomass burning, anthropogenic, primary biogenic, and secondary biogenic. Despite human activity being concentrated in a few coastal areas, the PMF results indicate that the anthropogenic source factor is the dominant contributor to the VOC load (38 %), followed by the background/biomass burning source factor originating in the free troposphere (33 %), and by the primary (15 %) and secondary biogenic (14 %) source factors. FLEXPART-AROME simulations showed that the observatory was most sensitive to anthropogenic emissions west of Maïdo while the strongest biogenic contributions coincided with air masses passing over the northeastern part of La Réunion. At night, the observatory is often located in the free troposphere, while during the day, the measurements are influenced by mesoscale sources. Interquartile ranges of nighttime 30 min average mixing ratios of methanol (CH3OH), CH3CN, acetaldehyde (CH3CHO), formic acid (HCOOH), acetone (CH3COCH3), acetic acid (CH3COOH), and methyl ethyl ketone (MEK), representative for the atmospheric composition of the free troposphere, were found to be 525–887, 79–110, 61–101, 172–335, 259–379, 64–164, and 11–21 pptv, respectively.

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The role of semi-volatile organic compounds in the mesoscale evolution of biomass burning aerosol: a modeling case study of the 2010 mega-fire event in Russia

Atmospheric Chemistry and Physics ◽

10.5194/acp-15-13269-2015 ◽

2015 ◽

Vol 15 (23) ◽

pp. 13269-13297 ◽

Cited By ~ 23

Author(s):

I. B. Konovalov ◽

M. Beekmann ◽

E. V. Berezin ◽

H. Petetin ◽

T. Mielonen ◽

...

Keyword(s):

Air Pollution ◽

Volatile Organic Compounds ◽

Organic Compounds ◽

Biomass Burning ◽

Organic Aerosol ◽

Pollution Monitoring ◽

Basis Set ◽

Aerosol Emission ◽

Volatile Organic ◽

Aerosol Modeling

Abstract. Chemistry transport models (CTMs) are an indispensable tool for studying and predicting atmospheric and climate effects associated with carbonaceous aerosol from open biomass burning (BB); this type of aerosol is known to contribute significantly to both global radiative forcing and to episodes of air pollution in regions affected by wildfires. Improving model performance requires systematic comparison of simulation results with measurements of BB aerosol and elucidation of possible reasons for discrepancies between them, which, by default, are frequently attributed in the literature to uncertainties in emission data. Based on published laboratory data on the atmospheric evolution of BB aerosol and using the volatility basis set (VBS) framework for organic aerosol modeling, we examined the importance of taking gas-particle partitioning and oxidation of semi-volatile organic compounds (SVOCs) into account in simulations of the mesoscale evolution of smoke plumes from intense wildfires that occurred in western Russia in 2010. Biomass burning emissions of primary aerosol components were constrained with PM10 and CO data from the air pollution monitoring network in the Moscow region. The results of the simulations performed with the CHIMERE CTM were evaluated by considering, in particular, the ratio of smoke-related enhancements in PM10 and CO concentrations (ΔPM10 and ΔCO) measured in Finland (in the city of Kuopio), nearly 1000 km downstream of the fire emission sources. It is found that while the simulations based on a "conventional" approach to BB aerosol modeling (disregarding oxidation of SVOCs and assuming organic aerosol material to be non-volatile) strongly underestimated values of ΔPM10/ΔCO observed in Kuopio (by a factor of 2), employing the "advanced" representation of atmospheric processing of organic aerosol material resulted in bringing the simulations to a much closer agreement with the ground measurements. Furthermore, taking gas-particle partitioning and oxidation of SVOCs into account is found to result in a major improvement of the agreement of simulations and satellite measurements of aerosol optical depth, as well as in considerable changes in predicted aerosol composition and top-down BB aerosol emission estimates derived from AOD measurements.

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PTR-MS measurements of non-methane volatile organic compounds during an intensive field campaign at the summit of Mount Tai, China, in June 2006

Atmospheric Chemistry and Physics ◽

10.5194/acp-10-7085-2010 ◽

2010 ◽

Vol 10 (15) ◽

pp. 7085-7099 ◽

Cited By ~ 22

Author(s):

S. Inomata ◽

H. Tanimoto ◽

S. Kato ◽

J. Suthawaree ◽

Y. Kanaya ◽

...

Keyword(s):

Volatile Organic Compounds ◽

Organic Compounds ◽

Biomass Burning ◽

Proton Transfer Reaction ◽

Temporal Variations ◽

Field Campaign ◽

Flame Ionization ◽

Volatile Organic ◽

Aldehydes And Ketones ◽

On Line

Abstract. Owing to recent industrialization, Central East China has become a significant source of air pollutants. To examine the processes controlling the chemistry and transport of tropospheric ozone, we performed on-line measurements of non-methane volatile organic compounds (NMVOCs) as part of an intensive field campaign at Mount Tai, China, in June 2006 (MTX2006), using proton transfer reaction mass spectrometry (PTR-MS). Temporal variations of NMVOCs were recorded in mass-scan mode from m/z17 to m/z 300 during 12–30 June 2006. More than thirty kinds of NMVOCs were detected up to m/z 160, including alkenes, aromatics, alcohols, aldehydes, and ketones. In combination with non-methane hydrocarbon data obtained by a gas chromatography with flame ionization detection, it was found that oxygenated VOCs were the predominant NMVOCs. Diurnal variations depending mainly on local photochemistry were observed during 24–28 June. During the night of 12 June, we observed an episode of high NMVOCs concentrations attributed to the burning of agricultural biomass. The ΔNMVOCs/ΔCO ratios derived by PTR-MS measurements for this episode (with biomass burning (BB) plume) and during 16–23 June (without BB plume) are compared to emission ratios from various types of biomass burning as reviewed by Andreae and Merlet (2001) and to ratios recently measured by PTR-MS in tropical forests (Karl et al., 2007) and at urban sites (Warneke et al., 2007).

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