Recent advances in understanding secondary organic aerosol: Implications for global climate forcing

Reviews of Geophysics, Journal Year: 2017, Volume and Issue: 55(2), P. 509 - 559

Published: May 18, 2017

Abstract Anthropogenic emissions and land use changes have modified atmospheric aerosol concentrations size distributions over time. Understanding preindustrial conditions in organic due to anthropogenic activities is important because these features (1) influence estimates of radiative forcing (2) can confound the historical response climate increases greenhouse gases. Secondary (SOA), formed atmosphere by oxidation gases, represents a major fraction global submicron‐sized aerosol. Over past decade, significant advances understanding SOA properties formation mechanisms occurred through measurements, yet current models typically do not comprehensively include all processes. This review summarizes some developments during decade formation. We highlight importance processes that growth particles sizes relevant for clouds forcing, including extremely low volatility organics gas phase, acid‐catalyzed multiphase chemistry isoprene epoxydiols, particle‐phase oligomerization, physical such as viscosity. Several highlighted this are complex interdependent nonlinear effects on properties, formation, evolution SOA. Current neglect complexity nonlinearity thus less likely accurately predict project future sensitivity Efforts also needed rank most influential process‐related interactions, so be represented chemistry‐climate models.

Language: Английский

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Aerosol Mixing State: Measurements, Modeling, and Impacts

Reviews of Geophysics, Journal Year: 2019, Volume and Issue: 57(2), P. 187 - 249

Published: March 21, 2019

Abstract Atmospheric aerosols are complex mixtures of different chemical species, and individual particles exist in many shapes morphologies. Together, these characteristics contribute to the aerosol mixing state. This review provides an overview measurement techniques probe state, discusses how state is represented atmospheric models at scales, synthesizes our knowledge state's impact on climate‐relevant properties, such as cloud condensation ice nucleating particle concentrations, optical properties. We present findings within a framework that defines along with appropriate metrics quantify it. Future research directions identified, focus need for integrating measurements modeling.

Language: Английский

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Evaluating the performance of five different chemical ionization techniques for detecting gaseous oxygenated organic species

Atmospheric measurement techniques, Journal Year: 2019, Volume and Issue: 12(4), P. 2403 - 2421

Published: April 17, 2019

Abstract. The impact of aerosols on climate and air quality remains poorly understood due to multiple factors. One the current limitations is incomplete understanding contribution oxygenated products, generated from gas-phase oxidation volatile organic compounds (VOCs), aerosol formation. Indeed, atmospheric gaseous chemical processes yield thousands (highly) species, spanning a wide range formulas, functional groups and, consequently, volatilities. While recent mass spectrometric developments have allowed extensive on-line detection myriad playing central role in chemistry, detailed quantification characterization this diverse group extremely challenging. To address challenge, we evaluated capability state-of-the-art spectrometers equipped with different ionization sources detect products formed α-Pinene ozonolysis under various conditions. Five were deployed simultaneously for chamber study. Two pressure interface time-of-flight (CI-APi-TOF) nitrate amine reagent ion chemistries an iodide spectrometer (TOF-CIMS) used. Additionally, proton transfer reaction (PTR-TOF 8000) new “vocus” PTR-TOF also deployed. In study, compared around 1000 between each five instruments, aim determining which VOCs (OVOCs) methods sensitive identifying regions where two or more instruments able species similar molecular formulae. We utilized large variability conditions (including VOCs, ozone, NOx OH scavenger concentrations) our newly constructed simulation comprehensive correlation analysis all instruments. This analysis, combined estimated concentrations identified molecules instrument, yielded both expected surprising results. As anticipated based earlier studies, PTR only ones measure precursor VOC, TOF-CIMS efficiently detected many semi-volatile (SVOCs) three oxygen atoms, CI-APi-TOF was mainly highly (O > 5) (HOMs). addition, vocus showed good agreement SVOC, including organonitrates. agreed well HOM dimers. However, loadings experiments caused be considerably depleted, causing nonlinear responses monomers. study explores highlights benefits currently available spectrometry instrumentation characterizing variety OVOCs atmosphere. specifically shown case ozonolysis, expect general findings valid other VOC–oxidant systems. discussed no single instrument configuration can deemed better worse than others, as optimal particular ultimately depends specific target

Language: Английский

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Atmospheric Aerosol Chemistry: Spectroscopic and Microscopic Advances

Analytical Chemistry, Journal Year: 2016, Volume and Issue: 89(1), P. 430 - 452

Published: Nov. 28, 2016

ADVERTISEMENT RETURN TO ISSUEPREVReviewNEXTAtmospheric Aerosol Chemistry: Spectroscopic and Microscopic AdvancesAndrew P. Ault*†‡ Jessica L. Axson‡View Author Information† Department of Chemistry, University Michigan, Ann Arbor, Michigan 48109, United States‡ Environmental Health Sciences, States*E-mail: [email protected]. Phone: 734-763-4212.Cite this: Anal. Chem. 2017, 89, 1, 430–452Publication Date (Web):November 28, 2016Publication History Published online28 November 2016Published inissue 3 January 2017https://pubs.acs.org/doi/10.1021/acs.analchem.6b04670https://doi.org/10.1021/acs.analchem.6b04670review-articleACS PublicationsCopyright © 2016 American Chemical SocietyRequest reuse permissionsArticle Views5290Altmetric-Citations135LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum full text article downloads since 2008 (both PDF HTML) across all institutions individuals. These metrics regularly updated to reflect usage leading up last few days.Citations number other articles citing this article, calculated by Crossref daily. Find more information about citation counts.The Altmetric Attention Score is a quantitative measure attention that research has received online. Clicking on donut icon will load page at altmetric.com with additional details score social media presence for given article. how calculated. Share Add toView InAdd Full Text ReferenceAdd Description ExportRISCitationCitation abstractCitation referencesMore Options onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Aerosols,Nanoparticles,Particles,Raman spectroscopy,X-rays Get e-Alerts

Language: Английский

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Long-term measurements of volatile organic compounds highlight the importance of sesquiterpenes for the atmospheric chemistry of a boreal forest

Atmospheric chemistry and physics, Journal Year: 2018, Volume and Issue: 18(19), P. 13839 - 13863

Published: Oct. 1, 2018

Abstract. The concentrations of terpenoids (isoprene; monoterpenes, MTs; and sesquiterpenes, SQTs) oxygenated volatile organic compounds (OVOCs; i.e. aldehydes, alcohols, acetates acids, VOAs) were investigated during 2 years at a boreal forest site in Hyytiälä, Finland, using situ gas chromatograph mass spectrometers (GC-MSs). Seasonal diurnal variations terpenoid OVOC as well their relationship with meteorological factors studied. Of the VOCs examined, C2–C7 unbranched VOAs showed highest concentrations, mainly due to low reactivity. terpenoids, MTs site, but seven different highly reactive SQTs also detected. monthly daily mean most aldehydes dependent on temperature. exponential correlation temperature was found for SQT (β-caryophyllene) summer. could be explained by sources, sinks vertical mixing. MT strongly affected Based correlations mixing layer height (MLH), simple proxies developed estimating concentrations. To estimate importance compound groups local atmospheric chemistry, reactivity main oxidants (hydroxyl radical, OH; nitrate NO3; ozone, O3) production rates oxidation products (OxPRs) calculated. dominated OH NO3 radical greatly impacted O3 even though 30 times lower than important products. Since show high secondary aerosol (SOA) yields, results clearly indicate SOA production.

Language: Английский

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Molecular Characterization of Organosulfur Compounds in Biodiesel and Diesel Fuel Secondary Organic Aerosol

Environmental Science & Technology, Journal Year: 2016, Volume and Issue: 51(1), P. 119 - 127

Published: Dec. 8, 2016

Secondary organic aerosol (SOA), formed in the photooxidation of diesel fuel, biodiesel and 20% fuel/80% fuel mixture, are prepared under high-NOx conditions presence absence sulfur dioxide (SO2), ammonia (NH3), relative humidity (RH). The composition condensed-phase compounds SOA is measured using several complementary techniques including mass spectrometry (AMS), high-resolution nanospray desorption electrospray ionization (nano-DESI/HRMS), ultrahigh resolution accuracy 21T Fourier transform ion cyclotron resonance (21T FT-ICR MS). Results demonstrate that sulfuric acid condensed organosulfur species experiments with SO2 present particles. Fewer high experiments, performed at RH 90%, comparison done dry conditions. There a strong overlap observed this study previous field chamber studies SOA. Many MS peaks organosulfates (R–OS(O)2OH) previously designated as biogenic or unknown origin might have originated from anthropogenic sources, such hydrocarbons fuel.

Language: Английский

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The importance of intermediates ring-opening in preventing photocatalyst deactivation during toluene decomposition

Applied Catalysis B Environment and Energy, Journal Year: 2020, Volume and Issue: 272, P. 118977 - 118977

Published: April 18, 2020

Language: Английский

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Exposure of Lung Epithelial Cells to Photochemically Aged Secondary Organic Aerosol Shows Increased Toxic Effects

Environmental Science & Technology Letters, Journal Year: 2018, Volume and Issue: 5(7), P. 424 - 430

Published: June 11, 2018

Adverse health effects due to exposure particulate matter (PM) are among the most important global environmental risks. However, of secondary organic aerosols (SOA), a major component aerosol, largely unknown. Here we exposed lung epithelial cells (A549) fresh and aged SOA particles investigated effect atmospheric aging on cell viability gene expression. Naphthalene- α-pinene-derived were formed in an oxidation flow reactor that simulates formation dominated by OH radical under NOx-free conditions. The mass chemical composition characterized on-line using scanning mobility particle sizer aerosol spectrometer. Fresh directed air–liquid interface system. Aged naphthalene- somewhat more toxic than SOA. naphthalene contained peroxide levels higher those level induction Nrf2 signaling increased following Given prevalence its observed toxicity, this study calls for studies aimed at understanding underlying mechanics.

Language: Английский

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Source apportionment of PM2.5 across China using LOTOS-EUROS

Atmospheric Environment, Journal Year: 2017, Volume and Issue: 164, P. 370 - 386

Published: June 3, 2017

Language: Английский

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Synergistic O ₃ + OH oxidation pathway to extremely low-volatility dimers revealed in β-pinene secondary organic aerosol

Proceedings of the National Academy of Sciences, Journal Year: 2018, Volume and Issue: 115(33), P. 8301 - 8306

Published: Aug. 3, 2018

Dimeric compounds contribute significantly to the formation and growth of atmospheric secondary organic aerosol (SOA) derived from monoterpene oxidation. However, mechanisms dimer production, in particular relevance gas- vs. particle-phase chemistry, remain unclear. Here, through a combination mass spectrometric, chromatographic, synthetic techniques, we identify suite dimeric (C15-19H24-32O5-11) formed concerted O3 OH oxidation β-pinene (i.e., accretion O3- OH-derived products/intermediates). These dimers account for an appreciable fraction (5.9-25.4%) SOA are designated as extremely low-volatility compounds. Certain dimers, characterized covalent esters, conclusively shown form heterogeneous while evidence production via gas-phase reactions is also presented. The synergistic + represents potentially significant, heretofore-unidentified source SOA. This reactivity suggests that current treatment sum products originating isolated individual precursors fails accurately reflect complexity pathways at play real atmosphere. Accounting role ambient could help resolve discrepancy between measured burden predicted by regional air quality global climate models.

Language: Английский

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