Aging of Atmospheric Brown Carbon Aerosol

ACS Earth and Space Chemistry, Journal Year: 2021, Volume and Issue: 5(4), P. 722 - 748

Published: April 5, 2021

Emitted by numerous primary sources and formed secondary sources, atmospheric brown carbon (BrC) aerosol is chemically complex. As BrC ages in the atmosphere via a variety of chemical physical processes, its composition optical properties change significantly, altering impacts on climate. Research past decade has considerably expanded our understanding reactions both gas condensed phases. We review these recent advances aging chemistry with focus phase leading to formation, aqueous in-cloud particle reactions. Connections are made between single component proxies more complex mixtures as well laboratory field measurements chemistry. General conclusions that can darken particles over short time scales hours close source considerable photobleaching oxidative whitening will occur when day or removed from source.

Language: Английский

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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

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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

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Formation of secondary organic aerosols from anthropogenic precursors in laboratory studies

npj Climate and Atmospheric Science, Journal Year: 2022, Volume and Issue: 5(1)

Published: March 24, 2022

Abstract Aerosols produced from the oxidation of volatile/semi-volatile organic compounds (VOCs/SVOCs), known as secondary aerosol (SOA), account for a significant fraction atmospheric airborne particles. This paper reviews current understanding SOA formation gas-phase with focus on anthropogenic precursors and their reaction products simulation chamber studies. The review summarises major derived main groups (e.g., alkanes, aromatics), yields factors controlling formation. We highlight that lab-derived yield depends strongly upon, not only concentrations oxidants but also conditions.

Language: Английский

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Radical chemistry in oxidation flow reactors for atmospheric chemistry research

Chemical Society Reviews, Journal Year: 2020, Volume and Issue: 49(9), P. 2570 - 2616

Published: Jan. 1, 2020

We summarize the studies on chemistry in oxidation flow reactor and discuss its atmospheric relevance.

Language: Английский

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Laboratory Investigation of Renoxification from the Photolysis of Inorganic Particulate Nitrate

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 55(2), P. 854 - 861

Published: Jan. 4, 2021

Nitrogen oxides (NOx) play a key role in regulating the oxidizing capacity of atmosphere through controlling abundance O3, OH, and other important gas particle species. Some recent studies have suggested that particulate nitrate, which is conventionally considered as ultimate oxidation product NOx, can undergo "renoxification" via photolysis, recycling NOx HONO back to phase. However, there are large discrepancies estimates importance this channel, with reported renoxification rate constants spanning three orders magnitude. In addition, previous laboratory derived constant using bulk samples collected on substrates instead suspended particles. work, we study submicron sodium ammonium nitrate controlled photolysis experiments an environmental chamber. We find that, under atmospherically relevant wavelengths relative humidities, inorganic releases less than 10 times rapidly gaseous nitric acid, putting our measurements low end recently constants. To extent conditions representative real atmosphere, from appears limited contributing OH budgets remote environments. These results based simplified model systems; future should investigate more complex aerosol mixtures represent broader spectrum properties better constrain ambient aerosols.

Language: Английский

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Fire Influence on Regional to Global Environments and Air Quality (FIREX‐AQ)

Journal of Geophysical Research Atmospheres, Journal Year: 2022, Volume and Issue: 128(2)

Published: Dec. 30, 2022

Abstract The NOAA/NASA Fire Influence on Regional to Global Environments and Air Quality (FIREX‐AQ) experiment was a multi‐agency, inter‐disciplinary research effort to: (a) obtain detailed measurements of trace gas aerosol emissions from wildfires prescribed fires using aircraft, satellites ground‐based instruments, (b) make extensive suborbital remote sensing fire dynamics, (c) assess local, regional, global modeling fires, (d) strengthen connections observables the ground such as fuels fuel consumption satellite products burned area radiative power. From Boise, ID western were studied with NASA DC‐8 two NOAA Twin Otter aircraft. high‐altitude ER‐2 deployed Palmdale, CA observe some these in conjunction overpasses other Further conducted three mobile laboratories sites, 17 different forecast analyses for fire, air quality climate implications. Salina, KS investigated 87 smaller Southeast in‐situ data collection. Sampling by all platforms designed measure gases aerosols multiple transects capture chemical transformation perform observations smoke plumes under day night conditions. linked consumed power orbital collected during overflights sampling fuels.

Language: Английский

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Formation of secondary organic aerosol from wildfire emissions enhanced by long-time ageing

Nature Geoscience, Journal Year: 2024, Volume and Issue: 17(2), P. 124 - 129

Published: Jan. 9, 2024

Language: Английский

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How emissions uncertainty influences the distribution and radiative impacts of smoke from fires in North America

Atmospheric chemistry and physics, Journal Year: 2020, Volume and Issue: 20(4), P. 2073 - 2097

Published: Feb. 26, 2020

Abstract. Fires and the aerosols that they emit impact air quality, health, climate, but abundance properties of carbonaceous aerosol (both black carbon organic carbon) from biomass burning (BB) remain uncertain poorly constrained. We aim to explore uncertainties associated with fire emissions their quality radiative impacts underlying dry matter consumed factors. To investigate this, we compare model simulations a global chemical transport model, GEOS-Chem, driven by variety emission inventories surface airborne observations (BC) (OA) concentrations satellite-derived optical depth (AOD). focus on two fire-detection-based and/or burned-area-based (FD-BA) using burned area active counts, respectively, i.e., Global Fire Emissions Database version 4 (GFED4s) small fires INventory NCAR 1.5 (FINN1.5), power (FRP)-based approaches, Quick Emission Dataset 2.4 (QFED2.4) Assimilation System 1.2 (GFAS1.2). show that, across inventories, BB (BBA) differ factor 7 over North America differences, not factors, drive this spread. find QFED2.4 generally overestimate BC and, lesser extent, OA fire-influenced aircraft campaigns in (ARCTAS DC3) Interagency Monitoring Protected Visual Environments (IMPROVE) network, while FINN1.5 substantially underestimate concentrations. The GFED4s GFAS1.2-driven provide best agreement mass at (IMPROVE), observed aloft (DC3 ARCTAS), AOD MODIS America. also sensitivity simulation including an enhanced source secondary (SOA) fires, based NOAA Lab 2016 experiments, produces substantial additional OA; however, spread primary estimates implies magnitude SOA can be neither confirmed nor ruled out when comparing against explored here. Given uncertainty emissions, as represented these four sizeable range 2012 annual BBA PM2.5 population-weighted exposure Canada contiguous US (0.5 1.6 µg m−3). estimated direct effect (−0.11 −0.048 W m−2) is large comparable forcing (−0.09 Fifth Assessment Report (AR5) Intergovernmental Panel Climate Change (IPCC). Our analysis suggests challenges our ability accurately characterize smoke climate.

Language: Английский

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Biogenic secondary organic aerosols: A review on formation mechanism, analytical challenges and environmental impacts

Chemosphere, Journal Year: 2020, Volume and Issue: 262, P. 127771 - 127771

Published: Aug. 7, 2020

Language: Английский

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