Emission of trace gases and aerosols from biomass burning – an updated assessment

Atmospheric chemistry and physics, Journal Year: 2019, Volume and Issue: 19(13), P. 8523 - 8546

Published: July 4, 2019

Abstract. Since the publication of compilation biomass burning emission factors by Andreae and Merlet (2001), a large number studies have greatly expanded amount available data on emissions from various types burning. Using essentially same methodology as this paper presents an updated factors. The over 370 published were critically evaluated integrated into consistent format. Several new categories added, species for which are presented was increased 93 to 121. Where field still insufficient, estimates based appropriate extrapolation techniques proposed. For key species, compared with previously values. Based these global activity estimates, I derived pyrogenic important released

Language: Английский

---

Proton-Transfer-Reaction Mass Spectrometry: Applications in Atmospheric Sciences

Chemical Reviews, Journal Year: 2017, Volume and Issue: 117(21), P. 13187 - 13229

Published: Oct. 4, 2017

Proton-transfer-reaction mass spectrometry (PTR-MS) has been widely used to study the emissions, distributions, and chemical evolution of volatile organic compounds (VOCs) in atmosphere. The applications PTR-MS have greatly promoted understanding VOC sources their roles air-quality issues. In past two decades, many new spectrometric techniques applied instruments, performance improved significantly. This Review summarizes these developments recent atmospheric sciences. We discuss latest instrument development characterization work on including use time-of-flight analyzers types ion guiding interfaces. Here we review what learned about specificity different product signals for important VOCs. present some highlights research using observations urban air, biomass-burning plumes, forested regions, oil natural gas production agricultural facilities, marine environment, laboratory studies, indoor air. Finally, will summarize further that are aimed at improving sensitivity extending its other sciences, e.g., aerosol measurements OH reactivity measurements.

Language: Английский

---

Non-methane organic gas emissions from biomass burning: identification, quantification, and emission factors from PTR-ToF during the FIREX 2016 laboratory experiment

Atmospheric chemistry and physics, Journal Year: 2018, Volume and Issue: 18(5), P. 3299 - 3319

Published: March 7, 2018

Abstract. Volatile and intermediate-volatility non-methane organic gases (NMOGs) released from biomass burning were measured during laboratory-simulated wildfires by proton-transfer-reaction time-of-flight mass spectrometry (PTR-ToF). We identified NMOG contributors to more than 150 PTR ion masses using gas chromatography (GC) pre-separation with electron ionization, H3O+ chemical NO+ an extensive literature review, time series correlation, providing higher certainty for identifications has been previously available. Our interpretation of the PTR-ToF spectrum accounts nearly 90 % detected across all fuel types. The relative contributions different NMOGs individual exact are mostly similar many fires measurements compared corresponding open-path Fourier transform infrared spectroscopy (OP-FTIR), broadband cavity-enhanced (ACES), iodide ionization (I− CIMS) where possible. majority comparisons have slopes near 1 values linear correlation coefficient, R2, > 0.8, including compounds that not frequently reported PTR-MS such as ammonia, hydrogen cyanide (HCN), nitrous acid (HONO), propene. exceptions include methylglyoxal known be difficult measure one or deployed instruments. fire-integrated emission ratios CO factors 18 types provided. Finally, we provide overview characteristics species. Non-aromatic oxygenated most abundant. Furans aromatics, while less abundant, comprise a large portion OH reactivity. reactivity, its major contributors, volatility distribution emissions can change considerably over course fire.

Language: Английский

---

Aging Effects on Biomass Burning Aerosol Mass and Composition: A Critical Review of Field and Laboratory Studies

Environmental Science & Technology, Journal Year: 2019, Volume and Issue: 53(17), P. 10007 - 10022

Published: July 31, 2019

Biomass burning is a major source of atmospheric particulate matter (PM) with impacts on health, climate, and air quality. The particles vapors within biomass plumes undergo chemical physical aging as they are transported downwind. Field measurements the evolution PM plume age range from net decreases to increases, most showing little no change. In contrast, laboratory studies tend show significant mass increases average. On other hand, similar effects average composition (e.g., oxygen-to-carbon ratio) reported for lab field studies. Currently, there consensus mechanisms that lead these observed similarities differences. This review summarizes available observations aging-related aerosol concentrations markers, discusses four broad hypotheses explain variability between campaigns: (1) in emissions chemistry, (2) differences dilution/entrainment, (3) losses chambers lines, (4) timing initial measurement, baseline which changes estimated. We conclude concise set research needs advancing our understanding aerosol.

Language: Английский

---

Quantification of organic aerosol and brown carbon evolution in fresh wildfire plumes

Proceedings of the National Academy of Sciences, Journal Year: 2020, Volume and Issue: 117(47), P. 29469 - 29477

Published: Nov. 4, 2020

Significance Wildfire emissions in the western United States have had increasingly larger impacts on air quality, health, and climate forcing recent decades. However, our understanding of how wildfire plume composition evolves remains incomplete. Particularly, evolution carbonaceous material, including fine particle mass (PM 2.5 ) light-absorbing brown carbon, has remained elusive because limited knowledge about interplay between primary subsequent chemical physical transformations that convert material vapors particles. Using a comprehensive analysis situ smoke measurements combination with simulation chamber experiments, we quantitatively assess versus secondary organic particulate matter carbon light absorption authentic wildfires plumes. These results improve fundamental evolution.

Language: Английский

---

Field measurements of trace gases and aerosols emitted by peat fires in Central Kalimantan, Indonesia, during the 2015 El Niño

Atmospheric chemistry and physics, Journal Year: 2016, Volume and Issue: 16(18), P. 11711 - 11732

Published: Sept. 21, 2016

Abstract. Peat fires in Southeast Asia have become a major annual source of trace gases and particles to the regional–global atmosphere. The assessment their influence on atmospheric chemistry, climate, air quality, health has been uncertain partly due lack field measurements smoke characteristics. During strong 2015 El Niño event we deployed mobile sampling team Indonesian province Central Kalimantan island Borneo made first, or rare, gases, aerosol optical properties, mass emissions for authentic peat burning at various depths different types. This paper reports gas obtained by Fourier transform infrared spectroscopy, whole sampling, photoacoustic extinctiometers (405 870 nm), small subset data from analyses particulate filters. provide emission factors (EFs; grams compound per kilogram biomass burned) up ∼ 90 including CO2, CO, CH4, non-methane hydrocarbons C10, 15 oxygenated organic compounds, NH3, HCN, NOx, OCS, HCl, etc. modified combustion efficiency (MCE) sources ranged 0.693 0.835 with an average 0.772 ± 0.053 (n = 35), indicating essentially pure smoldering combustion, were not initially strongly lofted. (EF as g kg−1) carbon dioxide (1564 77), monoxide (291 49), methane (9.51 4.74), hydrogen cyanide (5.75 1.60), acetic acid (3.89 1.65), ammonia (2.86 1.00), methanol (2.14 1.22), ethane (1.52 0.66), dihydrogen (1.22 1.01), propylene (1.07 0.53), propane (0.989 0.644), ethylene (0.961 0.528), benzene (0.954 0.394), formaldehyde (0.867 0.479), hydroxyacetone (0.860 0.433), furan (0.772 0.035), acetaldehyde (0.697 0.460), acetone (0.691 0.356). These support significant revision EFs CO2 (−8 %), CH4 (−55 NH3 (−86 CO (+39 other compared widely used recommendations tropical based lab study single sample published 2003. BTEX compounds (benzene, toluene, ethylbenzene, xylenes) are important toxics precursors emitted total 1.5 0.6 kg−1. Formaldehyde is probably toxic most likely cause local exposures that exceed recommended levels. results reasonable agreement recent “overlap species,” lending importance finding produces large acetamide, acrolein, methylglyoxal, etc., which measurable equipment implying value continued similar efforts. measured include scattering absorption coefficients Bscat EF Babs, m2 kg−1 fuel albedo (SSA) 405 nm, well Ångström exponents (AAE). By coupling co-located filter estimated black (BC) (g coefficient (MAC, g−1) bulk (OC) brown (BrC). Consistent minimal flaming, BC negligible (0.0055 0.0016 kg−1). Aerosol nm was 52 times larger than BrC contributed 96 % nm. Average AAE 4.97 0.65 (range, 4.29–6.23). SSA (0.974 0.016) marginally lower (0.998 0.001). facilitate modeling climate-relevant properties across much UV/visible spectrum high demonstrate dominance aerosol. Comparing Babs simultaneously OC filters suggests low MAC ( 0.1) OC, expected BC/OC ratio pyrolysis (at MCE), opposed glowing higher producing seen increase MCE (r2 0.65).

Language: Английский

---

High- and low-temperature pyrolysis profiles describe volatile organic compound emissions from western US wildfire fuels

Atmospheric chemistry and physics, Journal Year: 2018, Volume and Issue: 18(13), P. 9263 - 9281

Published: July 3, 2018

Abstract. Biomass burning is a large source of volatile organic compounds (VOCs) and many other trace species to the atmosphere, which can act as precursors secondary pollutants such ozone fine particles. Measurements performed with proton-transfer-reaction time-of-flight mass spectrometer during FIREX 2016 laboratory intensive were analyzed positive matrix factorization (PMF), in order understand instantaneous variability VOC emissions from biomass burning, simplify description these types emissions. Despite complexity emissions, we found that solution including just two emission profiles, are spectral representations relative abundances emitted VOCs, explained on average 85 % across various fuels representative western US (including coniferous chaparral fuels). In addition, profiles remarkably similar almost all fuel tested. For example, correlation coefficient r2 each profile between ponderosa pine (coniferous tree) manzanita (chaparral) higher than 0.84. The compositional differences appear be related pyrolysis processes biopolymers at high low temperatures. These thought main “High-temperature” “low-temperature” do not correspond exactly commonly used “flaming” “smoldering” categories described by modified combustion efficiency (MCE). atmospheric properties (e.g., OH reactivity, volatility, etc) high- low-temperature significantly different. We also describe previously reported data for field burns.

Language: Английский

---

OH chemistry of non-methane organic gases (NMOGs) emitted from laboratory and ambient biomass burning smoke: evaluating the influence of furans and oxygenated aromatics on ozone and secondary NMOG formation

Atmospheric chemistry and physics, Journal Year: 2019, Volume and Issue: 19(23), P. 14875 - 14899

Published: Dec. 10, 2019

Abstract. Chamber oxidation experiments conducted at the Fire Sciences Laboratory in 2016 are evaluated to identify important chemical processes contributing hydroxy radical (OH) chemistry of biomass burning non-methane organic gases (NMOGs). Based on decay primary carbon measured by proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS), it is confirmed that furans and oxygenated aromatics among NMOGs emitted from western United States fuel types with highest reactivities towards OH. The formation secondary NMOG masses PTR-ToF-MS iodide-clustering ionization (I-CIMS) interpreted using a box model employing modified version Master Chemical Mechanism (v. 3.3.1) includes OH furan, 2-methylfuran, 2,5-dimethylfuran, furfural, 5-methylfurfural, guaiacol. supports assignment major I-CIMS signals series anhydrides furanones formed primarily through furan chemistry. This mechanism applied Lagrangian used previously real plume. customized reproduces NMOGs, such as maleic anhydride. simulations without furans, estimated contributed up 10 % ozone over 90 anhydride within first 4 h oxidation. It shown present plume transported several days, which demonstrates utility markers for aged plumes.

Language: Английский

---

Oxygenated Aromatic Compounds are Important Precursors of Secondary Organic Aerosol in Biomass-Burning Emissions

Environmental Science & Technology, Journal Year: 2020, Volume and Issue: 54(14), P. 8568 - 8579

Published: June 19, 2020

Biomass burning is the largest combustion-related source of volatile organic compounds (VOCs) to atmosphere. We describe development a state-of-the-science model simulate photochemical formation secondary aerosol (SOA) from biomass-burning emissions observed in dry (RH <20%) environmental chamber experiments. The modeling supported by (i) new oxidation measurements, (ii) detailed concurrent measurements SOA precursors emissions, and (iii) parameters for heterocyclic oxygenated aromatic based on historical find that compounds, including phenols methoxyphenols, account slightly less than 60% formed help our explain variability mass (R2 = 0.68) O/C 0.69) enhancement ratios across 11 Despite abundant included furans contribute ∼20% total SOA. use pyrolysis-temperature-based or averaged emission profiles represent precursors, rather those specific each fire, provide similar results within 20%. Our findings demonstrate necessity accounting aromatics their chemical mechanisms.

Language: Английский

---

Emissions of Trace Organic Gases From Western U.S. Wildfires Based on WE‐CAN Aircraft Measurements

Journal of Geophysical Research Atmospheres, Journal Year: 2021, Volume and Issue: 126(11)

Published: May 9, 2021

Abstract We present emission measurements of volatile organic compounds (VOCs) for western U.S. wildland fires made on the NSF/NCAR C‐130 research aircraft during Western Wildfire Experiment Cloud Chemistry, Aerosol Absorption, and Nitrogen (WE‐CAN) field campaign in summer 2018. VOCs were measured with complementary instruments onboard C‐130, including a proton‐transfer‐reaction time‐of‐flight mass spectrometer (PTR‐ToF‐MS) two gas chromatography (GC)‐based methods. Agreement within combined instrument uncertainties (<60%) was observed most co‐measured VOCs. GC‐based speciated isomeric contributions to selected PTR‐ToF‐MS ion masses generally showed little fire‐to‐fire variation. report ratios (ERs) factors (EFs) 161 31 near‐fire smoke plume transects 24 specific individual sampled afternoon when burning conditions are typically active. Modified combustion efficiency (MCE) ranged from 0.85 0.94. The campaign‐average total VOC EF 26.1 ± 6.9 g kg −1 , approximately 67% which is accounted by oxygenated 10 abundantly emitted species contributed more than half mass. found that MCE alone explained nearly 70% variance emissions ( r 2 = 0.67) >50% 57 EFs representing carbon Finally, we variability fraction emissions, suggesting single speciation profile can describe wildfires coniferous ecosystems WE‐CAN.

Language: Английский

---