Articles | Volume 17, issue 2 
            
                
                    
            
            
            https://doi.org/10.5194/acp-17-1343-2017
                    © Author(s) 2017. This work is distributed under 
the Creative Commons Attribution 3.0 License.
                the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-17-1343-2017
                    © Author(s) 2017. This work is distributed under 
the Creative Commons Attribution 3.0 License.
                the Creative Commons Attribution 3.0 License.
Qualitative and quantitative analysis of atmospheric organosulfates in Centreville, Alabama
Anusha P. S. Hettiyadura
                                            Department of Chemistry, University of Iowa, Iowa City, IA, USA
                                        
                                    Thilina Jayarathne
                                            Department of Chemistry, University of Iowa, Iowa City, IA, USA
                                        
                                    Karsten Baumann
                                            Atmospheric Research & Analysis, Inc., Cary, NC, USA
                                        
                                    Allen H. Goldstein
                                            Department of Environmental Science, Policy, and Management,
University of California, Berkeley, CA, USA
                                        
                                    
                                            Department of Civil and Environmental Engineering, University of
California, Berkeley, CA, USA
                                        
                                    Joost A. de Gouw
                                            Chemical Sciences Division, Earth System Research Laboratory, National
Oceanic & Atmospheric Administration, Boulder, CO, USA
                                        
                                    Abigail Koss
                                            Chemical Sciences Division, Earth System Research Laboratory, National
Oceanic & Atmospheric Administration, Boulder, CO, USA
                                        
                                    Frank N. Keutsch
                                            Department of Chemistry, University of Wisconsin-Madison, Madison, WI,
USA
                                        
                                    
                                            now at: School of Engineering and Applied Sciences and
Department of Chemistry & Chemical Biology, Harvard University,
Cambridge, MA, USA
                                        
                                    Kate Skog
                                            Department of Chemistry, University of Wisconsin-Madison, Madison, WI,
USA
                                        
                                    
                                            now at: Department of Chemical & Environmental Engineering, Yale
University, New Haven, CT, USA
                                        
                                    Elizabeth A. Stone
CORRESPONDING AUTHOR
                                            
                                    
                                            Department of Chemistry, University of Iowa, Iowa City, IA, USA
                                        
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                                        Qindan Zhu, Bryan Place, Eva Y. Pfannerstill, Sha Tong, Huanxin Zhang, Jun Wang, Clara M. Nussbaumer, Paul Wooldridge, Benjamin C. Schulze, Caleb Arata, Anthony Bucholtz, John H. Seinfeld, Allen H. Goldstein, and Ronald C. Cohen
                                    Atmos. Chem. Phys., 23, 9669–9683, https://doi.org/10.5194/acp-23-9669-2023, https://doi.org/10.5194/acp-23-9669-2023, 2023
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                                                Nitrogen oxide (NOx) is a hazardous air pollutant, and it is the precursor of short-lived climate forcers like tropospheric ozone and aerosol particles. While NOx emissions from transportation has been strictly regulated, soil NOx emissions are overlooked. We use the airborne flux measurements to observe NOx emissions from highways and urban and cultivated soil land cover types. We show non-negligible soil NOx emissions, which are significantly underestimated in current model simulations.
                                            
                                            
                                        Kevin J. Nihill, Matthew M. Coggon, Christopher Y. Lim, Abigail R. Koss, Bin Yuan, Jordan E. Krechmer, Kanako Sekimoto, Jose L. Jimenez, Joost de Gouw, Christopher D. Cappa, Colette L. Heald, Carsten Warneke, and Jesse H. Kroll
                                    Atmos. Chem. Phys., 23, 7887–7899, https://doi.org/10.5194/acp-23-7887-2023, https://doi.org/10.5194/acp-23-7887-2023, 2023
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                                        Qing Ye, Matthew B. Goss, Jordan E. Krechmer, Francesca Majluf, Alexander Zaytsev, Yaowei Li, Joseph R. Roscioli, Manjula Canagaratna, Frank N. Keutsch, Colette L. Heald, and Jesse H. Kroll
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                                    Atmos. Chem. Phys., 22, 10173–10194, https://doi.org/10.5194/acp-22-10173-2022, https://doi.org/10.5194/acp-22-10173-2022, 2022
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                                    Atmos. Chem. Phys., 22, 9877–9893, https://doi.org/10.5194/acp-22-9877-2022, https://doi.org/10.5194/acp-22-9877-2022, 2022
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                                        Emily B. Franklin, Lindsay D. Yee, Bernard Aumont, Robert J. Weber, Paul Grigas, and Allen H. Goldstein
                                    Atmos. Meas. Tech., 15, 3779–3803, https://doi.org/10.5194/amt-15-3779-2022, https://doi.org/10.5194/amt-15-3779-2022, 2022
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                                                The composition of atmospheric aerosols are extremely complex, containing hundreds of thousands of estimated individual compounds. The majority of these compounds have never been catalogued in widely used databases, making them extremely difficult for atmospheric chemists to identify and analyze. In this work, we present Ch3MS-RF, a machine-learning-based model to enable characterization of complex mixtures and prediction of structure-specific properties of unidentifiable organic compounds.
                                            
                                            
                                        Vigneshkumar Balamurugan, Jia Chen, Zhen Qu, Xiao Bi, and Frank N. Keutsch
                                    Atmos. Chem. Phys., 22, 7105–7129, https://doi.org/10.5194/acp-22-7105-2022, https://doi.org/10.5194/acp-22-7105-2022, 2022
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                                                In this study, we investigated the response of secondary pollutants to changes in precursor emissions, focusing on the formation of secondary PM, during the COVID-19 lockdown period. We show that, due to the decrease in primary NOx emissions, atmospheric oxidizing capacity is increased. The nighttime increase in ozone, caused by less NO titration, results in higher NO3 radicals, which contribute significantly to the formation of PM nitrates. O3 should be limited in order to control PM pollution.
                                            
                                            
                                        Andrew J. Lindsay, Daniel C. Anderson, Rebecca A. Wernis, Yutong Liang, Allen H. Goldstein, Scott C. Herndon, Joseph R. Roscioli, Christoph Dyroff, Ed C. Fortner, Philip L. Croteau, Francesca Majluf, Jordan E. Krechmer, Tara I. Yacovitch, Walter B. Knighton, and Ezra C. Wood
                                    Atmos. Chem. Phys., 22, 4909–4928, https://doi.org/10.5194/acp-22-4909-2022, https://doi.org/10.5194/acp-22-4909-2022, 2022
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                                                Wildfire smoke dramatically impacts air quality and often has elevated concentrations of ozone. We present measurements of ozone and its precursors at a rural site periodically impacted by wildfire smoke. Measurements of total peroxy radicals, key ozone precursors that have been studied little within wildfires, compare well with chemical box model predictions. Our results indicate no serious issues with using current chemistry mechanisms to model chemistry in aged wildfire plumes.
                                            
                                            
                                        Kun Zhang, Zhiqiang Liu, Xiaojuan Zhang, Qing Li, Andrew Jensen, Wen Tan, Ling Huang, Yangjun Wang, Joost de Gouw, and Li Li
                                    Atmos. Chem. Phys., 22, 4853–4866, https://doi.org/10.5194/acp-22-4853-2022, https://doi.org/10.5194/acp-22-4853-2022, 2022
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                                                A significant increase in O3 concentrations was found during the lockdown period of COVID-19 in most areas of China. By field measurements coupled with machine learning, an observation-based model (OBM) and sensitivity analysis, we found the changes in the NOx / VOC ratio were a key reason for the significant rise in O3. To restrain O3 pollution, more efforts should be devoted to the control of anthropogenic OVOCs, alkenes and aromatics.
                                            
                                            
                                        Delaney B. Kilgour, Gordon A. Novak, Jon S. Sauer, Alexia N. Moore, Julie Dinasquet, Sarah Amiri, Emily B. Franklin, Kathryn Mayer, Margaux Winter, Clare K. Morris, Tyler Price, Francesca Malfatti, Daniel R. Crocker, Christopher Lee, Christopher D. Cappa, Allen H. Goldstein, Kimberly A. Prather, and Timothy H. Bertram
                                    Atmos. Chem. Phys., 22, 1601–1613, https://doi.org/10.5194/acp-22-1601-2022, https://doi.org/10.5194/acp-22-1601-2022, 2022
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                                                We report measurements of gas-phase volatile organosulfur molecules made during a mesocosm phytoplankton bloom experiment. Dimethyl sulfide (DMS), methanethiol (MeSH), and benzothiazole accounted for on average over 90 % of total gas-phase sulfur emissions. This work focuses on factors controlling the production and emission of DMS and MeSH and the role of non-DMS molecules (such as MeSH and benzothiazole) in secondary sulfate formation in coastal marine environments.
                                            
                                            
                                        Dandan Wei, Hariprasad D. Alwe, Dylan B. Millet, Brandon Bottorff, Michelle Lew, Philip S. Stevens, Joshua D. Shutter, Joshua L. Cox, Frank N. Keutsch, Qianwen Shi, Sarah C. Kavassalis, Jennifer G. Murphy, Krystal T. Vasquez, Hannah M. Allen, Eric Praske, John D. Crounse, Paul O. Wennberg, Paul B. Shepson, Alexander A. T. Bui, Henry W. Wallace, Robert J. Griffin, Nathaniel W. May, Megan Connor, Jonathan H. Slade, Kerri A. Pratt, Ezra C. Wood, Mathew Rollings, Benjamin L. Deming, Daniel C. Anderson, and Allison L. Steiner
                                    Geosci. Model Dev., 14, 6309–6329, https://doi.org/10.5194/gmd-14-6309-2021, https://doi.org/10.5194/gmd-14-6309-2021, 2021
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                                                Over the past decade, understanding of isoprene oxidation has improved, and proper representation of isoprene oxidation and isoprene-derived SOA (iSOA) formation in canopy–chemistry models is now recognized to be important for an accurate understanding of forest–atmosphere exchange. The updated FORCAsT version 2.0 improves the estimation of some isoprene oxidation products and is one of the few canopy models currently capable of simulating SOA formation from monoterpenes and isoprene.
                                            
                                            
                                        Rebecca A. Wernis, Nathan M. Kreisberg, Robert J. Weber, Yutong Liang, John Jayne, Susanne Hering, and Allen H. Goldstein
                                    Atmos. Meas. Tech., 14, 6533–6550, https://doi.org/10.5194/amt-14-6533-2021, https://doi.org/10.5194/amt-14-6533-2021, 2021
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                                                cTAG is a new scientific instrument that measures concentrations of organic chemicals in the atmosphere. cTAG is the first instrument capable of measuring small, light chemicals as well as heavier chemicals and everything in between on a single detector, every hour. In this work we explain how cTAG works and some of the tests we performed to verify that it works properly and reliably. We also present measurements of alkanes that suggest they have three dominant sources in a Bay Area suburb.
                                            
                                            
                                        Benjamin A. Nault, Duseong S. Jo, Brian C. McDonald, Pedro Campuzano-Jost, Douglas A. Day, Weiwei Hu, Jason C. Schroder, James Allan, Donald R. Blake, Manjula R. Canagaratna, Hugh Coe, Matthew M. Coggon, Peter F. DeCarlo, Glenn S. Diskin, Rachel Dunmore, Frank Flocke, Alan Fried, Jessica B. Gilman, Georgios Gkatzelis, Jacqui F. Hamilton, Thomas F. Hanisco, Patrick L. Hayes, Daven K. Henze, Alma Hodzic, James Hopkins, Min Hu, L. Greggory Huey, B. Thomas Jobson, William C. Kuster, Alastair Lewis, Meng Li, Jin Liao, M. Omar Nawaz, Ilana B. Pollack, Jeffrey Peischl, Bernhard Rappenglück, Claire E. Reeves, Dirk Richter, James M. Roberts, Thomas B. Ryerson, Min Shao, Jacob M. Sommers, James Walega, Carsten Warneke, Petter Weibring, Glenn M. Wolfe, Dominique E. Young, Bin Yuan, Qiang Zhang, Joost A. de Gouw, and Jose L. Jimenez
                                    Atmos. Chem. Phys., 21, 11201–11224, https://doi.org/10.5194/acp-21-11201-2021, https://doi.org/10.5194/acp-21-11201-2021, 2021
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                                                Secondary organic aerosol (SOA) is an important aspect of poor air quality for urban regions around the world, where a large fraction of the population lives. However, there is still large uncertainty in predicting SOA in urban regions. Here, we used data from 11 urban campaigns and show that the variability in SOA production in these regions is predictable and is explained by key emissions. These results are used to estimate the premature mortality associated with SOA in urban regions.
                                            
                                            
                                        Eleni Dovrou, Kelvin H. Bates, Jean C. Rivera-Rios, Joshua L. Cox, Joshua D. Shutter, and Frank N. Keutsch
                                    Atmos. Chem. Phys., 21, 8999–9008, https://doi.org/10.5194/acp-21-8999-2021, https://doi.org/10.5194/acp-21-8999-2021, 2021
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                                                We examined the mechanism and products of oxidation of dissolved sulfur dioxide with the main isomers of isoprene hydroxyl hydroperoxides, via laboratory and model analysis. Two chemical mechanism pathways are proposed and the results provide an improved understanding of the broader atmospheric chemistry and role of multifunctional organic hydroperoxides, which should be the dominant VOC oxidation products under low-NO conditions, highlighting their significant contribution to sulfate formation.
                                            
                                            
                                        Jack C. Hensley, Adam W. Birdsall, Gregory Valtierra, Joshua L. Cox, and Frank N. Keutsch
                                    Atmos. Chem. Phys., 21, 8809–8821, https://doi.org/10.5194/acp-21-8809-2021, https://doi.org/10.5194/acp-21-8809-2021, 2021
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                                                We measured reactions of butenedial, an atmospheric dicarbonyl, in aqueous mixtures that mimic the conditions of aerosol particles. Major reaction products and rates were determined to assess their atmospheric relevance and to compare against other well-studied dicarbonyls. We suggest that the structure of the carbon backbone, not just the dominant functional group, plays a major role in dicarbonyl reactivity, influencing the fate and ability of dicarbonyls to produce brown carbon.
                                            
                                            
                                        Yutong Liang, Coty N. Jen, Robert J. Weber, Pawel K. Misztal, and Allen H. Goldstein
                                    Atmos. Chem. Phys., 21, 5719–5737, https://doi.org/10.5194/acp-21-5719-2021, https://doi.org/10.5194/acp-21-5719-2021, 2021
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                                                This article reports the molecular composition of smoke particles people in SF Bay Area were exposed to during northern California wildfires in Oct. 2017. Major components are sugars, acids, aromatics, and terpenoids. These observations can be used to better understand health impacts of smoke exposure. Tracer compounds indicate which fuels burned, including diterpenoids for softwood and syringyls for hardwood. A statistical analysis reveals a group of secondary compounds formed in daytime aging.
                                            
                                            
                                        Alexander Zaytsev, Martin Breitenlechner, Anna Novelli, Hendrik Fuchs, Daniel A. Knopf, Jesse H. Kroll, and Frank N. Keutsch
                                    Atmos. Meas. Tech., 14, 2501–2513, https://doi.org/10.5194/amt-14-2501-2021, https://doi.org/10.5194/amt-14-2501-2021, 2021
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                                                We have developed an online method for speciated measurements of organic peroxy radicals and stabilized Criegee intermediates using chemical derivatization combined with chemical ionization mass spectrometry. Chemical derivatization prevents secondary radical reactions and eliminates potential interferences. Comparison between our measurements and results from numeric modeling shows that the method can be used for the quantification of a wide range of atmospheric radicals and intermediates.
                                            
                                            
                                        Megan S. Claflin, Demetrios Pagonis, Zachary Finewax, Anne V. Handschy, Douglas A. Day, Wyatt L. Brown, John T. Jayne, Douglas R. Worsnop, Jose L. Jimenez, Paul J. Ziemann, Joost de Gouw, and Brian M. Lerner
                                    Atmos. Meas. Tech., 14, 133–152, https://doi.org/10.5194/amt-14-133-2021, https://doi.org/10.5194/amt-14-133-2021, 2021
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                                                We have developed a field-deployable gas chromatograph with thermal desorption preconcentration and detector switching between two high-resolution mass spectrometers for in situ measurements of volatile organic compounds (VOCs). This system combines chromatography with both proton transfer and electron ionization to offer fast time response and continuous molecular speciation. This technique was applied during the 2018 ATHLETIC campaign to characterize VOC emissions in an indoor environment.
                                            
                                            
                                        Lei Zhu, Gonzalo González Abad, Caroline R. Nowlan, Christopher Chan Miller, Kelly Chance, Eric C. Apel, Joshua P. DiGangi, Alan Fried, Thomas F. Hanisco, Rebecca S. Hornbrook, Lu Hu, Jennifer Kaiser, Frank N. Keutsch, Wade Permar, Jason M. St. Clair, and Glenn M. Wolfe
                                    Atmos. Chem. Phys., 20, 12329–12345, https://doi.org/10.5194/acp-20-12329-2020, https://doi.org/10.5194/acp-20-12329-2020, 2020
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                                                We develop a validation platform for satellite HCHO retrievals using in situ observations from 12 aircraft campaigns. The platform offers an alternative way to quickly assess systematic biases in HCHO satellite products over large domains and long periods, facilitating optimization of retrieval settings and the minimization of retrieval biases. Application to the NASA operational HCHO product indicates that relative biases range from −44.5 % to +112.1 % depending on locations and seasons.
                                            
                                            
                                        Aikaterini Bougiatioti, Athanasios Nenes, Jack J. Lin, Charles A. Brock, Joost A. de Gouw, Jin Liao, Ann M. Middlebrook, and André Welti
                                    Atmos. Chem. Phys., 20, 12163–12176, https://doi.org/10.5194/acp-20-12163-2020, https://doi.org/10.5194/acp-20-12163-2020, 2020
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                                                The number concentration of droplets in clouds in the summertime in the southeastern United States is influenced by aerosol variations but limited by the strong competition for supersaturated water vapor. Concurrent variations in vertical velocity magnify the response of cloud droplet number to aerosol increases by up to a factor of 5. Omitting the covariance of vertical velocity with aerosol number may therefore bias estimates of the cloud albedo effect from aerosols.
                                            
                                            
                                        James M. Roberts, Chelsea E. Stockwell, Robert J. Yokelson, Joost de Gouw, Yong Liu, Vanessa Selimovic, Abigail R. Koss, Kanako Sekimoto, Matthew M. Coggon, Bin Yuan, Kyle J. Zarzana, Steven S. Brown, Cristina Santin, Stefan H. Doerr, and Carsten Warneke
                                    Atmos. Chem. Phys., 20, 8807–8826, https://doi.org/10.5194/acp-20-8807-2020, https://doi.org/10.5194/acp-20-8807-2020, 2020
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                                                We measured total reactive nitrogen, Nr, in lab fires from western North American fuels, along with measurements of individual nitrogen compounds. We measured the amount of N that gets converted to inactive compounds (avg. 70 %), and the amount that is accounted for by individual species (85 % of remaining N). We provide guidelines for how the reactive nitrogen is distributed among individual compounds such as NOx and ammonia. This will help estimates and predictions of wildfire emissions.
                                            
                                            
                                        Christopher D. Cappa, Christopher Y. Lim, David H. Hagan, Matthew Coggon, Abigail Koss, Kanako Sekimoto, Joost de Gouw, Timothy B. Onasch, Carsten Warneke, and Jesse H. Kroll
                                    Atmos. Chem. Phys., 20, 8511–8532, https://doi.org/10.5194/acp-20-8511-2020, https://doi.org/10.5194/acp-20-8511-2020, 2020
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                                                Smoke from combustion of a wide range of biomass fuels (e.g., leaves, twigs, logs, peat, and dung) was photochemically aged in a small chamber for up to 8 d of equivalent atmospheric aging. Upon aging, the particle chemical composition and ability to absorb sunlight changed owing to reactions in both the gas and particulate phases. We developed a model to explain the observations and used this to derive insights into the aging of smoke in the atmosphere.
                                            
                                            
                                        Ryan Schmedding, Quazi Z. Rasool, Yue Zhang, Havala O. T. Pye, Haofei Zhang, Yuzhi Chen, Jason D. Surratt, Felipe D. Lopez-Hilfiker, Joel A. Thornton, Allen H. Goldstein, and William Vizuete
                                    Atmos. Chem. Phys., 20, 8201–8225, https://doi.org/10.5194/acp-20-8201-2020, https://doi.org/10.5194/acp-20-8201-2020, 2020
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                                                Accurate model prediction of aerosol concentrations is a known challenge. It is assumed in many modeling systems that aerosols are in a homogeneously mixed phase state. It has been observed that aerosols do phase separate and can form a highly viscous organic shell with an aqueous core impacting the formation processes of aerosols. This work is a model implementation to determine an aerosol's phase state using glass transition temperature and aerosol composition.
                                            
                                            
                                        Md. Robiul Islam, Thilina Jayarathne, Isobel J. Simpson, Benjamin Werden, John Maben, Ashley Gilbert, Puppala S. Praveen, Sagar Adhikari, Arnico K. Panday, Maheswar Rupakheti, Donald R. Blake, Robert J. Yokelson, Peter F. DeCarlo, William C. Keene, and Elizabeth A. Stone
                                    Atmos. Chem. Phys., 20, 2927–2951, https://doi.org/10.5194/acp-20-2927-2020, https://doi.org/10.5194/acp-20-2927-2020, 2020
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                                                The Kathmandu Valley experiences high levels of air pollution. In this study, atmospheric gases and particulate matter were characterized by online and off-line measurements, with an emphasis on understanding their sources. The major sources of particulate matter and trace gases were identified as garbage burning, biomass burning, and vehicles. The majority of secondary organic aerosol was attributed to anthropogenic precursors, while a minority was attributed to biogenic gases.
                                            
                                            
                                        Joseph R. Salazar, Benton T. Cartledge, John P. Haynes, Rachel York-Marini, Allen L. Robinson, Greg T. Drozd, Allen H. Goldstein, Sirine C. Fakra, and Brian J. Majestic
                                    Atmos. Chem. Phys., 20, 1849–1860, https://doi.org/10.5194/acp-20-1849-2020, https://doi.org/10.5194/acp-20-1849-2020, 2020
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                                                The solubility of atmospheric iron is important in human health and environmental chemistry. To understand the origin of water-soluble iron in urban areas, tailpipe emissions were collected from 32 low-emitting vehicles, from which iron solubility averaged 30 % (0–82 %), more than 10 times the average in the Earth's crust. Water-soluble iron was independent of almost all exhaust components and of the iron phase in the particles but was correlated with specific exhaust-derived organic compounds.
                                            
                                            
                                        Abigail R. Koss, Manjula R. Canagaratna, Alexander Zaytsev, Jordan E. Krechmer, Martin Breitenlechner, Kevin J. Nihill, Christopher Y. Lim, James C. Rowe, Joseph R. Roscioli, Frank N. Keutsch, and Jesse H. Kroll
                                    Atmos. Chem. Phys., 20, 1021–1041, https://doi.org/10.5194/acp-20-1021-2020, https://doi.org/10.5194/acp-20-1021-2020, 2020
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                                                Oxidation chemistry of organic compounds in the atmosphere produces a diverse spectrum of products. This diversity is difficult to represent in air quality and climate models, and in laboratory experiments it results in large and complex datasets. This work evaluates several methods to simplify the chemistry of oxidation systems in environmental chambers, including positive matrix factorization, hierarchical clustering analysis, and gamma kinetics parameterization.
                                            
                                            
                                        Alexander Zaytsev, Abigail R. Koss, Martin Breitenlechner, Jordan E. Krechmer, Kevin J. Nihill, Christopher Y. Lim, James C. Rowe, Joshua L. Cox, Joshua Moss, Joseph R. Roscioli, Manjula R. Canagaratna, Douglas R. Worsnop, Jesse H. Kroll, and Frank N. Keutsch
                                    Atmos. Chem. Phys., 19, 15117–15129, https://doi.org/10.5194/acp-19-15117-2019, https://doi.org/10.5194/acp-19-15117-2019, 2019
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                                                Aromatic hydrocarbons contribute significantly to the production of tropospheric ozone and secondary organic aerosol (SOA). Here later-generation low-volatility oxygenated products from toluene and 1,2,4-TMB oxidation by OH are detected in the gas and particle phases. We show that these products, previously identified as highly oxygenated molecules (HOMs), are formed in more than one pathway with differing numbers of reaction steps with OH. They also make up a significant fraction of SOA.
                                            
                                            
                                        Matthew M. Coggon, Christopher Y. Lim, Abigail R. Koss, Kanako Sekimoto, Bin Yuan, Jessica B. Gilman, David H. Hagan, Vanessa Selimovic, Kyle J. Zarzana, Steven S. Brown, James M. Roberts, Markus Müller, Robert Yokelson, Armin Wisthaler, Jordan E. Krechmer, Jose L. Jimenez, Christopher Cappa, Jesse H. Kroll, Joost de Gouw, and Carsten Warneke
                                    Atmos. Chem. Phys., 19, 14875–14899, https://doi.org/10.5194/acp-19-14875-2019, https://doi.org/10.5194/acp-19-14875-2019, 2019
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                                                Wildfire emissions significantly contribute to adverse air quality; however, the chemical processes that lead to hazardous pollutants, such as ozone, are not fully understood. In this study, we describe laboratory experiments where we simulate the atmospheric chemistry of smoke emitted from a range of biomass fuels. We show that certain understudied compounds, such as furans and phenolic compounds, are significant contributors to pollutants formed as a result of typical atmospheric oxidation.
                                            
                                            
                                        Jiajue Chai, David J. Miller, Eric Scheuer, Jack Dibb, Vanessa Selimovic, Robert Yokelson, Kyle J. Zarzana, Steven S. Brown, Abigail R. Koss, Carsten Warneke, and Meredith Hastings
                                    Atmos. Meas. Tech., 12, 6303–6317, https://doi.org/10.5194/amt-12-6303-2019, https://doi.org/10.5194/amt-12-6303-2019, 2019
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                                                Isotopic analysis offers a potential tool to distinguish between sources and interpret transformation pathways of atmospheric species. We applied recently developed techniques in our lab to characterize the isotopic composition of reactive nitrogen species (NOx, HONO, HNO3, pNO3-) in fresh biomass burning emissions. Intercomparison with other techniques confirms the suitability of our methods, allowing for future applications of our techniques in a variety of environments.
                                            
                                            
                                        Rupert Holzinger, W. Joe F. Acton, William J. Bloss, Martin Breitenlechner, Leigh R. Crilley, Sébastien Dusanter, Marc Gonin, Valerie Gros, Frank N. Keutsch, Astrid Kiendler-Scharr, Louisa J. Kramer, Jordan E. Krechmer, Baptiste Languille, Nadine Locoge, Felipe Lopez-Hilfiker, Dušan Materić, Sergi Moreno, Eiko Nemitz, Lauriane L. J. Quéléver, Roland Sarda Esteve, Stéphane Sauvage, Simon Schallhart, Roberto Sommariva, Ralf Tillmann, Sergej Wedel, David R. Worton, Kangming Xu, and Alexander Zaytsev
                                    Atmos. Meas. Tech., 12, 6193–6208, https://doi.org/10.5194/amt-12-6193-2019, https://doi.org/10.5194/amt-12-6193-2019, 2019
                            Adam W. Birdsall, Jack C. Hensley, Paige S. Kotowitz, Andrew J. Huisman, and Frank N. Keutsch
                                    Atmos. Chem. Phys., 19, 14195–14209, https://doi.org/10.5194/acp-19-14195-2019, https://doi.org/10.5194/acp-19-14195-2019, 2019
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                                                We have measured the evaporation rates of butenedial, a four-carbon dialdehyde produced in the atmosphere, from individual levitated particles. Effective vapor pressures and Henry's law constants, which characterize the compound's gas-particle partitioning behavior, were determined. The important role of hydration reactions was observed under both dry and humid conditions, as well as a salting-out effect in the presence of sodium chloride or sodium sulfate.
                                            
                                            
                                        Joshua D. Shutter, Norton T. Allen, Thomas F. Hanisco, Glenn M. Wolfe, Jason M. St. Clair, and Frank N. Keutsch
                                    Atmos. Meas. Tech., 12, 6079–6089, https://doi.org/10.5194/amt-12-6079-2019, https://doi.org/10.5194/amt-12-6079-2019, 2019
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                                                A new mid-infrared and ultra-portable formaldehyde (HCHO) sensor from Aeris Technologies is characterized and evaluated against well-established laser-induced fluorescence (LIF) instrumentation. The Aeris sensor displays linear behavior (R squared > 0.94) and shows good agreement with LIF instruments. While the compact sensor is not currently a replacement for the most sensitive research-grade instrumentation available, its sub-ppbv precision is sufficient for indoor and outdoor HCHO monitoring.
                                            
                                            
                                        Christopher Y. Lim, David H. Hagan, Matthew M. Coggon, Abigail R. Koss, Kanako Sekimoto, Joost de Gouw, Carsten Warneke, Christopher D. Cappa, and Jesse H. Kroll
                                    Atmos. Chem. Phys., 19, 12797–12809, https://doi.org/10.5194/acp-19-12797-2019, https://doi.org/10.5194/acp-19-12797-2019, 2019
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                                                Wildfires are a large source of gases and particles to the atmosphere, both of which impact human health and climate. The amount and composition of particles from wildfires can change with time in the atmosphere; however, the impact of aging is not well understood. In a series of controlled laboratory experiments, we show that the particles are oxidized and a significant fraction of the gas-phase carbon (24 %–56 %) is converted to particle mass over the course of several days in the atmosphere.
                                            
                                            
                                        Eleni Dovrou, Christopher Y. Lim, Manjula R. Canagaratna, Jesse H. Kroll, Douglas R. Worsnop, and Frank N. Keutsch
                                    Atmos. Meas. Tech., 12, 5303–5315, https://doi.org/10.5194/amt-12-5303-2019, https://doi.org/10.5194/amt-12-5303-2019, 2019
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                                                Measurement techniques commonly used to analyze particulate matter composition can result in the possible misidentification of sulfur-containing species, especially for the case of sulfate and hydroxymethanesulfonate (HMS). The efficiency and limitations of these techniques, along with a method that enables further studies of the contribution of sulfur-containing species, S(IV) versus S(VI), to particulate matter under low-light atmospheric conditions, are described in this work.
                                            
                                            
                                        Xin Chen, Dylan B. Millet, Hanwant B. Singh, Armin Wisthaler, Eric C. Apel, Elliot L. Atlas, Donald R. Blake, Ilann Bourgeois, Steven S. Brown, John D. Crounse, Joost A. de Gouw, Frank M. Flocke, Alan Fried, Brian G. Heikes, Rebecca S. Hornbrook, Tomas Mikoviny, Kyung-Eun Min, Markus Müller, J. Andrew Neuman, Daniel W. O'Sullivan, Jeff Peischl, Gabriele G. Pfister, Dirk Richter, James M. Roberts, Thomas B. Ryerson, Stephen R. Shertz, Chelsea R. Thompson, Victoria Treadaway, Patrick R. Veres, James Walega, Carsten Warneke, Rebecca A. Washenfelder, Petter Weibring, and Bin Yuan
                                    Atmos. Chem. Phys., 19, 9097–9123, https://doi.org/10.5194/acp-19-9097-2019, https://doi.org/10.5194/acp-19-9097-2019, 2019
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                                                Volatile organic compounds (VOCs) affect air quality and modify the lifetimes of other pollutants. We combine a high-resolution 3-D atmospheric model with an ensemble of aircraft observations to perform an integrated analysis of the VOC budget over North America. We find that biogenic emissions provide the main source of VOC reactivity even in most major cities. Our findings point to key gaps in current models related to oxygenated VOCs and to the distribution of VOCs in the free troposphere.
                                            
                                            
                                        Benjamin L. Deming, Demetrios Pagonis, Xiaoxi Liu, Douglas A. Day, Ranajit Talukdar, Jordan E. Krechmer, Joost A. de Gouw, Jose L. Jimenez, and Paul J. Ziemann
                                    Atmos. Meas. Tech., 12, 3453–3461, https://doi.org/10.5194/amt-12-3453-2019, https://doi.org/10.5194/amt-12-3453-2019, 2019
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                                                Losses or measurement delays of gas-phase compounds sampled through tubing are important to atmospheric science. Here we characterize 14 tubing materials by measuring the effects on step changes in organic compound concentration. We find that polymeric tubings exhibit absorptive partitioning behaviour while glass and metal tubings show adsorptive partitioning. Adsorptive materials impart complex humidity, concentration, and VOC–VOC interaction dependencies that absorptive tubings do not.
                                            
                                            
                                        Min Zhong, Eri Saikawa, Alexander Avramov, Chen Chen, Boya Sun, Wenlu Ye, William C. Keene, Robert J. Yokelson, Thilina Jayarathne, Elizabeth A. Stone, Maheswar Rupakheti, and Arnico K. Panday
                                    Atmos. Chem. Phys., 19, 8209–8228, https://doi.org/10.5194/acp-19-8209-2019, https://doi.org/10.5194/acp-19-8209-2019, 2019
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                                                Air pollution is one of the most pressing environmental issues in the Kathmandu Valley, the capital city of Nepal. We estimated emissions from two of the major source types in the valley (vehicles and brick kilns) and found that they have significant impacts on air quality surrounding the valley. Our results highlight the importance of improving local emissions estimates for air quality modeling.
                                            
                                            
                                        Suzane S. de Sá, Luciana V. Rizzo, Brett B. Palm, Pedro Campuzano-Jost, Douglas A. Day, Lindsay D. Yee, Rebecca Wernis, Gabriel Isaacman-VanWertz, Joel Brito, Samara Carbone, Yingjun J. Liu, Arthur Sedlacek, Stephen Springston, Allen H. Goldstein, Henrique M. J. Barbosa, M. Lizabeth Alexander, Paulo Artaxo, Jose L. Jimenez, and Scot T. Martin
                                    Atmos. Chem. Phys., 19, 7973–8001, https://doi.org/10.5194/acp-19-7973-2019, https://doi.org/10.5194/acp-19-7973-2019, 2019
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                                                This study investigates the impacts of urban and fire emissions on the concentration, composition, and optical properties of submicron particulate matter (PM1) in central Amazonia during the dry season. Biomass-burning and urban emissions appeared to contribute at least 80 % of brown carbon absorption while accounting for 30 % to 40 % of the organic PM1 mass concentration. Only a fraction of the 9-fold increase in mass concentration relative to the wet season was due to biomass burning.
                                            
                                            
                                        Xiaoxi Liu, Benjamin Deming, Demetrios Pagonis, Douglas A. Day, Brett B. Palm, Ranajit Talukdar, James M. Roberts, Patrick R. Veres, Jordan E. Krechmer, Joel A. Thornton, Joost A. de Gouw, Paul J. Ziemann, and Jose L. Jimenez
                                    Atmos. Meas. Tech., 12, 3137–3149, https://doi.org/10.5194/amt-12-3137-2019, https://doi.org/10.5194/amt-12-3137-2019, 2019
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                                                Delays or losses of gases in sampling tubing and instrumental surfaces due to surface interactions can lead to inaccurate quantification. By sampling with several chemical ionization mass spectrometers and six tubing materials, we quantify delays of semivolatile organic compounds and small polar gases. Delay times generally increase with decreasing volatility or increasing polarity and also depend on materials. The method and results will inform inlet material selection and instrumental design.
                                            
                                            
                                        Hansol D. Lee, Chathuri P. Kaluarachchi, Elias S. Hasenecz, Jonic Z. Zhu, Eduard Popa, Elizabeth A. Stone, and Alexei V. Tivanski
                                    Atmos. Meas. Tech., 12, 2033–2042, https://doi.org/10.5194/amt-12-2033-2019, https://doi.org/10.5194/amt-12-2033-2019, 2019
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                                                Dry and wet aerosol deposition modes are commonly used to collect particles on a solid substrate for experiments. We demonstrate, using single-particle microscopy and bulk methods, how the substrate-deposited particles with two components can yield the same core–shell morphology but different shell thicknesses depending on the deposition method. Thus we strongly advise future works to use wet deposition when possible to obtain accurate assessment of the single-particle organic volume fraction.
                                            
                                            
                                        Alexander Zaytsev, Martin Breitenlechner, Abigail R. Koss, Christopher Y. Lim, James C. Rowe, Jesse H. Kroll, and Frank N. Keutsch
                                    Atmos. Meas. Tech., 12, 1861–1870, https://doi.org/10.5194/amt-12-1861-2019, https://doi.org/10.5194/amt-12-1861-2019, 2019
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                                                We present the development of a chemical ionization mass spectrometer which can be operated with either ammonium (NH4+) or hydronium (H3O+) as the reagent ion. We describe a mass spectrometric voltage scanning procedure based on collision-induced dissociation that allows us to determine the stability of detected ammonium–organic ions and hence constrain the sensitivity of the instrument to a wide range of organic compounds that cannot be calibrated directly.
                                            
                                            
                                        Anusha Priyadarshani Silva Hettiyadura, Ibrahim M. Al-Naiema, Dagen D. Hughes, Ting Fang, and Elizabeth A. Stone
                                    Atmos. Chem. Phys., 19, 3191–3206, https://doi.org/10.5194/acp-19-3191-2019, https://doi.org/10.5194/acp-19-3191-2019, 2019
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                                                This study examines anthropogenic influences on secondary organic aerosol at an urban site in Atlanta, Georgia. Organosulfates accounted for 16.5 % of PM2.5 organic carbon and were mostly derived from isoprene. In contrast to a rural forested site, Atlanta's isoprene-derived organosulfate concentrations were 2–6 times higher and accounted for twice as much organic carbon. Insights are provided as to which organosulfates should be measured in future studies and targeted for standard development.
                                            
                                            
                                        Shino Toma, Steve Bertman, Christopher Groff, Fulizi Xiong, Paul B. Shepson, Paul Romer, Kaitlin Duffey, Paul Wooldridge, Ronald Cohen, Karsten Baumann, Eric Edgerton, Abigail R. Koss, Joost de Gouw, Allen Goldstein, Weiwei Hu, and Jose L. Jimenez
                                    Atmos. Chem. Phys., 19, 1867–1880, https://doi.org/10.5194/acp-19-1867-2019, https://doi.org/10.5194/acp-19-1867-2019, 2019
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                                                Acyl peroxy nitrates (APN) were measured near the ground in Alabama using GC in summer 2013 to study biosphere–atmosphere interactions. APN were lower than measured in the SE USA over the past 2 decades. Historical data showed APN in 2013 was limited by NOx and production was dominated by biogenic precursors more than in the past. Isoprene-derived MPAN correlated with isoprene hydroxynitrates as NOx-dependent products. MPAN varied with aerosol growth, but not with N-containing particles.
                                            
                                            
                                        Coty N. Jen, Lindsay E. Hatch, Vanessa Selimovic, Robert J. Yokelson, Robert Weber, Arantza E. Fernandez, Nathan M. Kreisberg, Kelley C. Barsanti, and Allen H. Goldstein
                                    Atmos. Chem. Phys., 19, 1013–1026, https://doi.org/10.5194/acp-19-1013-2019, https://doi.org/10.5194/acp-19-1013-2019, 2019
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                                                Wildfires in the western US are occurring more frequently and burning larger land areas. Smoke from these fires will play a greater role in regional air quality and atmospheric chemistry than in the past. To help fire and climate modelers and atmospheric experimentalists better understand how smoke impacts the environment, we have separated, identified, classified, and quantified the thousands of organic compounds found in smoke and related their amounts emitted to fire conditions.
                                            
                                            
                                        Benjamin A. Nault, Pedro Campuzano-Jost, Douglas A. Day, Jason C. Schroder, Bruce Anderson, Andreas J. Beyersdorf, Donald R. Blake, William H. Brune, Yonghoon Choi, Chelsea A. Corr, Joost A. de Gouw, Jack Dibb, Joshua P. DiGangi, Glenn S. Diskin, Alan Fried, L. Gregory Huey, Michelle J. Kim, Christoph J. Knote, Kara D. Lamb, Taehyoung Lee, Taehyun Park, Sally E. Pusede, Eric Scheuer, Kenneth L. Thornhill, Jung-Hun Woo, and Jose L. Jimenez
                                    Atmos. Chem. Phys., 18, 17769–17800, https://doi.org/10.5194/acp-18-17769-2018, https://doi.org/10.5194/acp-18-17769-2018, 2018
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                                                Aerosol impacts visibility and human health in large cities. Sources of aerosols are still highly uncertain, especially for cities surrounded by numerous other cities. We use observations collected during the Korea–United States Air Quality study to determine sources of organic aerosol (OA). We find that secondary OA (SOA) is rapidly produced over Seoul, South Korea, and that the sources of the SOA originate from short-lived hydrocarbons, which originate from local emissions.
                                            
                                            
                                        Lindsay E. Hatch, Albert Rivas-Ubach, Coty N. Jen, Mary Lipton, Allen H. Goldstein, and Kelley C. Barsanti
                                    Atmos. Chem. Phys., 18, 17801–17817, https://doi.org/10.5194/acp-18-17801-2018, https://doi.org/10.5194/acp-18-17801-2018, 2018
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                                                We demonstrate the use of solid-phase extraction (SPE) disks for the untargeted analysis of gas-phase intermediate volatility and semi-volatile organic compounds emitted from biomass burning. SPE and Teflon filter samples collected from laboratory fires were analyzed by two-dimensional gas chromatography, with distinct differences in the observed chromatographic profiles as a function of 
fuel type. Fuel-dependent emissions and volatility differences among benzenediol isomers were captured.
                                            
                                            
                                        Ibrahim M. Al-Naiema, Anusha P. S. Hettiyadura, Henry W. Wallace, Nancy P. Sanchez, Carter J. Madler, Basak Karakurt Cevik, Alexander A. T. Bui, Josh Kettler, Robert J. Griffin, and Elizabeth A. Stone
                                    Atmos. Chem. Phys., 18, 15601–15622, https://doi.org/10.5194/acp-18-15601-2018, https://doi.org/10.5194/acp-18-15601-2018, 2018
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                                                By integrating newly developed tracers for anthropogenic secondary organic aerosol in source apportionment for the first time, we estimate that this source contributes 28 % of fine particle organic carbon in the Houston Ship Channel. Our approach can be used to evaluate anthropogenic, biogenic, and biomass burning contributions to secondary organic aerosols elsewhere in the world. Because anthropogenic emissions are potentially controllable, they provide an opportunity to improve air quality.
                                            
                                            
                                        Kyle J. Zarzana, Vanessa Selimovic, Abigail R. Koss, Kanako Sekimoto, Matthew M. Coggon, Bin Yuan, William P. Dubé, Robert J. Yokelson, Carsten Warneke, Joost A. de Gouw, James M. Roberts, and Steven S. Brown
                                    Atmos. Chem. Phys., 18, 15451–15470, https://doi.org/10.5194/acp-18-15451-2018, https://doi.org/10.5194/acp-18-15451-2018, 2018
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                                                Emissions of glyoxal and methylglyoxal from fuels common to the western United States were measured using cavity-enhanced spectroscopy, which provides a more selective measurement of those compounds than was previously available. Primary emissions of glyoxal were lower than previously reported and showed variability between the different fuel groups. However, emissions of glyoxal relative to formaldehyde were constant across almost all the fuel groups at 6 %–7 %.
                                            
                                            
                                        Azimeh Zare, Paul S. Romer, Tran Nguyen, Frank N. Keutsch, Kate Skog, and Ronald C. Cohen
                                    Atmos. Chem. Phys., 18, 15419–15436, https://doi.org/10.5194/acp-18-15419-2018, https://doi.org/10.5194/acp-18-15419-2018, 2018
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                                                Organic nitrates play an important role in concentrations and distribution of NOx, ozone and aerosol as the most important air pollutants. We develop a state-of-the-science detailed chemical mechanism representing individual organic nitrates, which is appropriate to use in air quality models and results in a more accurate simulation of atmospheric chemistry. Using this mechanism we explore production and removal processes of organic nitrates in a rural environment that are poorly constrained.
                                            
                                            
                                        J. Douglas Goetz, Michael R. Giordano, Chelsea E. Stockwell, Ted J. Christian, Rashmi Maharjan, Sagar Adhikari, Prakash V. Bhave, Puppala S. Praveen, Arnico K. Panday, Thilina Jayarathne, Elizabeth A. Stone, Robert J. Yokelson, and Peter F. DeCarlo
                                    Atmos. Chem. Phys., 18, 14653–14679, https://doi.org/10.5194/acp-18-14653-2018, https://doi.org/10.5194/acp-18-14653-2018, 2018
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                                                Size distributions and emission factors of submicron aerosol were quantified using online techniques for a variety of common but under-sampled combustion sources in South Asia: wood and dung cooking fires, groundwater pumps, brick kilns, trash burning, and open burning of crop residues. Optical properties (brown carbon light absorption and the absorption Ångström exponent, AAE) of the emissions were also investigated. Contextual comparisons to the literature and other NAMaSTE results were made.
                                            
                                            
                                        Jason A. Ducker, Christopher D. Holmes, Trevor F. Keenan, Silvano Fares, Allen H. Goldstein, Ivan Mammarella, J. William Munger, and Jordan Schnell
                                    Biogeosciences, 15, 5395–5413, https://doi.org/10.5194/bg-15-5395-2018, https://doi.org/10.5194/bg-15-5395-2018, 2018
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                                                We have developed an accurate method (SynFlux) to estimate ozone deposition and stomatal uptake across 103 flux tower sites (43 US, 60 Europe), where ozone concentrations and fluxes have not been measured. In all, the SynFlux public dataset provides monthly values of ozone dry deposition for 926 site years across a wide array of ecosystems. The SynFlux dataset will promote further applications to ecosystem, air quality, or climate modeling across the geoscience community.
                                            
                                            
                                        Suzane S. de Sá, Brett B. Palm, Pedro Campuzano-Jost, Douglas A. Day, Weiwei Hu, Gabriel Isaacman-VanWertz, Lindsay D. Yee, Joel Brito, Samara Carbone, Igor O. Ribeiro, Glauber G. Cirino, Yingjun Liu, Ryan Thalman, Arthur Sedlacek, Aaron Funk, Courtney Schumacher, John E. Shilling, Johannes Schneider, Paulo Artaxo, Allen H. Goldstein, Rodrigo A. F. Souza, Jian Wang, Karena A. McKinney, Henrique Barbosa, M. Lizabeth Alexander, Jose L. Jimenez, and Scot T. Martin
                                    Atmos. Chem. Phys., 18, 12185–12206, https://doi.org/10.5194/acp-18-12185-2018, https://doi.org/10.5194/acp-18-12185-2018, 2018
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                                                This study aimed at understanding and quantifying the changes in mass concentration and composition of submicron airborne particulate matter (PM) in Amazonia due to urban pollution. Downwind of Manaus, PM concentrations increased by up to 200 % under polluted compared with background conditions. The observed changes included contributions from both primary and secondary processes. The differences in organic PM composition suggested a shift in the pathways of secondary production with pollution.
                                            
                                            
                                        Juliane L. Fry, Steven S. Brown, Ann M. Middlebrook, Peter M. Edwards, Pedro Campuzano-Jost, Douglas A. Day, José L. Jimenez, Hannah M. Allen, Thomas B. Ryerson, Ilana Pollack, Martin Graus, Carsten Warneke, Joost A. de Gouw, Charles A. Brock, Jessica Gilman, Brian M. Lerner, William P. Dubé, Jin Liao, and André Welti
                                    Atmos. Chem. Phys., 18, 11663–11682, https://doi.org/10.5194/acp-18-11663-2018, https://doi.org/10.5194/acp-18-11663-2018, 2018
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                                                This paper uses measurements made during research aircraft flights through power plant smokestack emissions plumes as a natural laboratory in the field experiment. We investigated a specific source of airborne particulate matter from the combination of human-produced NOx pollutant emissions (the smokestack plumes) with isoprene emitted by naturally by trees in the southeastern United States. These field-based yields appear to be higher than those typically measured in chamber studies.
                                            
                                            
                                        Lindsay D. Yee, Gabriel Isaacman-VanWertz, Rebecca A. Wernis, Meng Meng, Ventura Rivera, Nathan M. Kreisberg, Susanne V. Hering, Mads S. Bering, Marianne Glasius, Mary Alice Upshur, Ariana Gray Bé, Regan J. Thomson, Franz M. Geiger, John H. Offenberg, Michael Lewandowski, Ivan Kourtchev, Markus Kalberer, Suzane de Sá, Scot T. Martin, M. Lizabeth Alexander, Brett B. Palm, Weiwei Hu, Pedro Campuzano-Jost, Douglas A. Day, Jose L. Jimenez, Yingjun Liu, Karena A. McKinney, Paulo Artaxo, Juarez Viegas, Antonio Manzi, Maria B. Oliveira, Rodrigo de Souza, Luiz A. T. Machado, Karla Longo, and Allen H. Goldstein
                                    Atmos. Chem. Phys., 18, 10433–10457, https://doi.org/10.5194/acp-18-10433-2018, https://doi.org/10.5194/acp-18-10433-2018, 2018
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                                                Biogenic volatile organic compounds react in the atmosphere to form secondary organic aerosol, yet the chemical pathways remain unclear. We collected filter samples and deployed a semi-volatile thermal desorption aerosol gas chromatograph in the central Amazon. We measured 30 sesquiterpenes and 4 diterpenes and find them to be important for reactive ozone loss. We estimate that sesquiterpene oxidation contributes at least 0.4–5 % (median 1 %) of observed submicron organic aerosol mass.
                                            
                                            
                                        Kanako Sekimoto, Abigail R. Koss, Jessica B. Gilman, Vanessa Selimovic, Matthew M. Coggon, Kyle J. Zarzana, Bin Yuan, Brian M. Lerner, Steven S. Brown, Carsten Warneke, Robert J. Yokelson, James M. Roberts, and Joost de Gouw
                                    Atmos. Chem. Phys., 18, 9263–9281, https://doi.org/10.5194/acp-18-9263-2018, https://doi.org/10.5194/acp-18-9263-2018, 2018
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                                                We found that on average 85 % of the VOC emissions from biomass burning across various fuels representative of the western US (including various coniferous and chaparral fuels) can be explained using only two emission profiles: (i) a high-temperature pyrolysis profile and (ii) a low-temperature pyrolysis profile. The high-temperature profile is quantitatively similar between different fuel types (r2 > 0.84), and likewise for the low-temperature profile.
                                            
                                            
                                        Hendrik Fuchs, Sascha Albrecht, Ismail–Hakki Acir, Birger Bohn, Martin Breitenlechner, Hans-Peter Dorn, Georgios I. Gkatzelis, Andreas Hofzumahaus, Frank Holland, Martin Kaminski, Frank N. Keutsch, Anna Novelli, David Reimer, Franz Rohrer, Ralf Tillmann, Luc Vereecken, Robert Wegener, Alexander Zaytsev, Astrid Kiendler-Scharr, and Andreas Wahner
                                    Atmos. Chem. Phys., 18, 8001–8016, https://doi.org/10.5194/acp-18-8001-2018, https://doi.org/10.5194/acp-18-8001-2018, 2018
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                                                The photooxidation of methyl vinyl ketone MVK, one of the most important products of isoprene that is emitted by plants,  was investigated in the atmospheric simulation chamber SAPHIR for conditions found in forested areas. The comparison of measured trace gas time series with model calculations shows a gap in the understanding of radical chemistry in the MVK oxidation scheme. The possibility of unimolecular isomerization reactions were investigated by means of quantum-chemical calculations.
                                            
                                            
                                        Si-Wan Kim, Vijay Natraj, Seoyoung Lee, Hyeong-Ahn Kwon, Rokjin Park, Joost de Gouw, Gregory Frost, Jhoon Kim, Jochen Stutz, Michael Trainer, Catalina Tsai, and Carsten Warneke
                                    Atmos. Chem. Phys., 18, 7639–7655, https://doi.org/10.5194/acp-18-7639-2018, https://doi.org/10.5194/acp-18-7639-2018, 2018
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                                                Formaldehyde (HCHO) is a hazardous air pollutant and is associated with tropospheric ozone production. HCHO has been monitored from space. In this study, to acquire high-quality satellite-based HCHO observations, we utilize fine-resolution atmospheric chemistry model results as an input to the computer code for satellite retrievals over the Los Angeles Basin. Our study indicates that the use of fine-resolution profile shapes helps to identify HCHO plumes from space.
                                            
                                            
                                        Amelie Bertrand, Giulia Stefenelli, Coty N. Jen, Simone M. Pieber, Emily A. Bruns, Haiyan Ni, Brice Temime-Roussel, Jay G. Slowik, Allen H. Goldstein, Imad El Haddad, Urs Baltensperger, André S. H. Prévôt, Henri Wortham, and Nicolas Marchand
                                    Atmos. Chem. Phys., 18, 7607–7624, https://doi.org/10.5194/acp-18-7607-2018, https://doi.org/10.5194/acp-18-7607-2018, 2018
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                                                A thermal desorption aerosol gas chromatograph coupled to an aerosol mass spectrometer (TAG–AMS) is connected to an atmospheric chamber. The setup serves the quantitative study of the impact of combustion conditions and atmospheric aging on the chemical fingerprint at the molecular level of biomass burning organic aerosol.
                                            
                                            
                                        Shouming Zhou, Jean C. Rivera-Rios, Frank N. Keutsch, and Jonathan P. D. Abbatt
                                    Atmos. Meas. Tech., 11, 3081–3089, https://doi.org/10.5194/amt-11-3081-2018, https://doi.org/10.5194/amt-11-3081-2018, 2018
                            Abigail R. Koss, Kanako Sekimoto, Jessica B. Gilman, Vanessa Selimovic, Matthew M. Coggon, Kyle J. Zarzana, Bin Yuan, Brian M. Lerner, Steven S. Brown, Jose L. Jimenez, Jordan Krechmer, James M. Roberts, Carsten Warneke, Robert J. Yokelson, and Joost de Gouw
                                    Atmos. Chem. Phys., 18, 3299–3319, https://doi.org/10.5194/acp-18-3299-2018, https://doi.org/10.5194/acp-18-3299-2018, 2018
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                                                Non-methane organic gases (NMOGs) were detected by proton-transfer-reaction mass spectrometry (PTR-ToF) during an extensive laboratory characterization of wildfire emissions. Identifications for PTR-ToF ion masses are proposed and supported by a combination of techniques. Overall excellent agreement with other instrumentation is shown. Scalable emission factors and ratios are reported for many newly reported reactive species. An analysis of chemical characteristics is presented.
                                            
                                            
                                        Vanessa Selimovic, Robert J. Yokelson, Carsten Warneke, James M. Roberts, Joost de Gouw, James Reardon, and David W. T. Griffith
                                    Atmos. Chem. Phys., 18, 2929–2948, https://doi.org/10.5194/acp-18-2929-2018, https://doi.org/10.5194/acp-18-2929-2018, 2018
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                                                We burned fuels representing western US wildfires in large-scale laboratory simulations to generate relevant emissions as confirmed by lab–field comparison. We report emission factors (EFs) for light scattering and absorption and BC along with SSA at 870 and 401 nm and AAE. We report EF for 22 trace gases that are major inorganic and organic emissions from flaming and smoldering. We report trace gas EF for species rarely (NH3) or not yet measured (e.g., HONO, acetic acid) for real US wildfires.
                                            
                                            
                                        Jingqiu Mao, Annmarie Carlton, Ronald C. Cohen, William H. Brune, Steven S. Brown, Glenn M. Wolfe, Jose L. Jimenez, Havala O. T. Pye, Nga Lee Ng, Lu Xu, V. Faye McNeill, Kostas Tsigaridis, Brian C. McDonald, Carsten Warneke, Alex Guenther, Matthew J. Alvarado, Joost de Gouw, Loretta J. Mickley, Eric M. Leibensperger, Rohit Mathur, Christopher G. Nolte, Robert W. Portmann, Nadine Unger, Mika Tosca, and Larry W. Horowitz
                                    Atmos. Chem. Phys., 18, 2615–2651, https://doi.org/10.5194/acp-18-2615-2018, https://doi.org/10.5194/acp-18-2615-2018, 2018
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                                                This paper is aimed at discussing progress in evaluating, diagnosing, and improving air quality and climate modeling using comparisons to SAS observations as a guide to thinking about improvements to mechanisms and parameterizations in models.
                                            
                                            
                                        Paul S. Romer, Kaitlin C. Duffey, Paul J. Wooldridge, Eric Edgerton, Karsten Baumann, Philip A. Feiner, David O. Miller, William H. Brune, Abigail R. Koss, Joost A. de Gouw, Pawel K. Misztal, Allen H. Goldstein, and Ronald C. Cohen
                                    Atmos. Chem. Phys., 18, 2601–2614, https://doi.org/10.5194/acp-18-2601-2018, https://doi.org/10.5194/acp-18-2601-2018, 2018
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                                                Observations of increased ozone on hotter days are widely reported, but the mechanisms driving this relationship remain uncertain. We use measurements from the rural southeastern United States to study how temperature affects ozone production. We find that changing NOx emissions, most likely from soil microbes, can be a major driver of increased ozone with temperature in the continental background. These findings suggest that ozone will increase with temperature under a wide range of conditions.
                                            
                                            
                                        Thilina Jayarathne, Chelsea E. Stockwell, Ashley A. Gilbert, Kaitlyn Daugherty, Mark A. Cochrane, Kevin C. Ryan, Erianto I. Putra, Bambang H. Saharjo, Ati D. Nurhayati, Israr Albar, Robert J. Yokelson, and Elizabeth A. Stone
                                    Atmos. Chem. Phys., 18, 2585–2600, https://doi.org/10.5194/acp-18-2585-2018, https://doi.org/10.5194/acp-18-2585-2018, 2018
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                                                Fine particulate matter (PM2.5) emissions from Indonesian peat burning were measured in situ. Fuel-based emission factors from 6.0–29.6 gPM kg-1. Detailed chemical analysis revealed high levels of organic carbon that was primarily water insoluble, little to no detectable elemental carbon, and alkane contributions to organic carbon in the range of 6 %. These data were used to estimate that 3.2–11 Tg of PM2.5 were emitted by the 2015 peat burning episodes in Indonesia.
                                            
                                            
                                        Thilina Jayarathne, Chelsea E. Stockwell, Prakash V. Bhave, Puppala S. Praveen, Chathurika M. Rathnayake, Md. Robiul Islam, Arnico K. Panday, Sagar Adhikari, Rashmi Maharjan, J. Douglas Goetz, Peter F. DeCarlo, Eri Saikawa, Robert J. Yokelson, and Elizabeth A. Stone
                                    Atmos. Chem. Phys., 18, 2259–2286, https://doi.org/10.5194/acp-18-2259-2018, https://doi.org/10.5194/acp-18-2259-2018, 2018
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                                                Emissions of fine particulate matter and its constituents were quantified for a variety of under-sampled combustion sources in South Asia: wood and dung cooking fires, generators, groundwater pumps, brick kilns, trash burning, and open burning of biomasses. Garbage burning and three-stone cooking fires were among the highest emitters, while servicing of motor vehicles significantly reduced PM. These data may be used in source apportionment and to update regional and global emission inventories.
                                            
                                            
                                        Catalina Tsai, Max Spolaor, Santo Fedele Colosimo, Olga Pikelnaya, Ross Cheung, Eric Williams, Jessica B. Gilman, Brian M. Lerner, Robert J. Zamora, Carsten Warneke, James M. Roberts, Ravan Ahmadov, Joost de Gouw, Timothy Bates, Patricia K. Quinn, and Jochen Stutz
                                    Atmos. Chem. Phys., 18, 1977–1996, https://doi.org/10.5194/acp-18-1977-2018, https://doi.org/10.5194/acp-18-1977-2018, 2018
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                                                Nitrous acid (HONO) photolysis is an important source of hydroxyl radicals (OH). Vertical HONO fluxes, observed in the snow-free, wintertime Uintah Basin, Utah, USA, show that chemical formation of HONO on the ground closes the HONO budget. Under high NOx conditions, HONO formation is most likely due to photo-enhanced conversion of NO2 on the ground. Under moderate to low NO2 conditions, photolysis of HNO3 on the ground seems to be the most likely source of HONO.
                                            
                                            
                                        Brett B. Palm, Suzane S. de Sá, Douglas A. Day, Pedro Campuzano-Jost, Weiwei Hu, Roger Seco, Steven J. Sjostedt, Jeong-Hoo Park, Alex B. Guenther, Saewung Kim, Joel Brito, Florian Wurm, Paulo Artaxo, Ryan Thalman, Jian Wang, Lindsay D. Yee, Rebecca Wernis, Gabriel Isaacman-VanWertz, Allen H. Goldstein, Yingjun Liu, Stephen R. Springston, Rodrigo Souza, Matt K. Newburn, M. Lizabeth Alexander, Scot T. Martin, and Jose L. Jimenez
                                    Atmos. Chem. Phys., 18, 467–493, https://doi.org/10.5194/acp-18-467-2018, https://doi.org/10.5194/acp-18-467-2018, 2018
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                                                Ambient air was oxidized by OH or O3 in an oxidation flow reactor during both wet and dry seasons in the GoAmazon2014/5 campaign to study secondary organic aerosol (SOA) formation. We investigated how much biogenic, urban, and biomass burning sources contributed to the ambient concentrations of SOA precursor gases and how their contributions changed diurnally and seasonally. SOA yields and hygroscopicity of organic aerosol in the oxidation flow reactor were also studied.
                                            
                                            
                                        Havala O. T. Pye, Andreas Zuend, Juliane L. Fry, Gabriel Isaacman-VanWertz, Shannon L. Capps, K. Wyat Appel, Hosein Foroutan, Lu Xu, Nga L. Ng, and Allen H. Goldstein
                                    Atmos. Chem. Phys., 18, 357–370, https://doi.org/10.5194/acp-18-357-2018, https://doi.org/10.5194/acp-18-357-2018, 2018
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                                                Thermodynamic modeling revealed that some but not all measurements of ammonium-to-sulfate ratios are consistent with theory. The measurement diversity likely explains the previously reported range of results regarding the suitability of thermodynamic modeling. Despite particles being predominantly phase separated, organic–inorganic interactions resulted in increased aerosol pH and partitioning towards the particle phase for highly oxygenated organic compounds compared to traditional methods.
                                            
                                            
                                        Adam W. Birdsall, Ulrich K. Krieger, and Frank N. Keutsch
                                    Atmos. Meas. Tech., 11, 33–47, https://doi.org/10.5194/amt-11-33-2018, https://doi.org/10.5194/amt-11-33-2018, 2018
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                                                We have developed a laboratory system that provides mass spectra of individual particles, roughly 20 microns in diameter, after they have been levitated in an electric field. Measured evaporation of polyethylene glycol particles was found to agree with a kinetic model. The system can be used to study fundamental chemical and physical processes involving particles that are difficult to isolate and study with other techniques, and hence improve our understanding of atmospheric particles.
                                            
                                            
                                        Demetrios Pagonis, Jordan E. Krechmer, Joost de Gouw, Jose L. Jimenez, and Paul J. Ziemann
                                    Atmos. Meas. Tech., 10, 4687–4696, https://doi.org/10.5194/amt-10-4687-2017, https://doi.org/10.5194/amt-10-4687-2017, 2017
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                                                Laboratory studies were conducted to investigate gas-wall partitioning of atmospheric organic compounds in Teflon tubing and inside an instrument used to monitor concentrations. Rapid partitioning caused time delays in instrument response that vary with tubing length and diameter, flow rate, and compound volatility. Tubing delay times of seconds to hours were described using a model that also included effects of instrument surfaces. The results can enable better design of air sampling systems.
                                            
                                            
                                        Robert C. Rhew, Malte Julian Deventer, Andrew A. Turnipseed, Carsten Warneke, John Ortega, Steve Shen, Luis Martinez, Abigail Koss, Brian M. Lerner, Jessica B. Gilman, James N. Smith, Alex B. Guenther, and Joost A. de Gouw
                                    Atmos. Chem. Phys., 17, 13417–13438, https://doi.org/10.5194/acp-17-13417-2017, https://doi.org/10.5194/acp-17-13417-2017, 2017
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                                                Alkenes emanate from both natural and anthropogenic sources and can contribute to atmospheric ozone production. This study measured 
                                            
                                        lightalkene (ethene, propene and butene) fluxes from a ponderosa pine forest using a novel relaxed eddy accumulation method, revealing much larger emissions than previously estimated and accounting for a significant fraction of OH reactivity. Emissions have a diurnal cycle related to sunlight and temperature, and the forest canopy appears to be the source.
Abigail Koss, Bin Yuan, Carsten Warneke, Jessica B. Gilman, Brian M. Lerner, Patrick R. Veres, Jeff Peischl, Scott Eilerman, Rob Wild, Steven S. Brown, Chelsea R. Thompson, Thomas Ryerson, Thomas Hanisco, Glenn M. Wolfe, Jason M. St. Clair, Mitchell Thayer, Frank N. Keutsch, Shane Murphy, and Joost de Gouw
                                    Atmos. Meas. Tech., 10, 2941–2968, https://doi.org/10.5194/amt-10-2941-2017, https://doi.org/10.5194/amt-10-2941-2017, 2017
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                                                Oil and gas extraction activity can cause air quality issues through emission of reactive chemicals. VOCs related to extraction operations in the United States were measured by PTR-ToF-MS from aircraft during the SONGNEX campaign in March–April 2015. The detailed analysis in this work provides a guide to interpreting PTR-ToF measurements in oil- and gas-producing regions, and it includes fundamental observations of VOC speciation and mixing ratios.
                                            
                                            
                                        Prettiny K. Ma, Yunliang Zhao, Allen L. Robinson, David R. Worton, Allen H. Goldstein, Amber M. Ortega, Jose L. Jimenez, Peter Zotter, André S. H. Prévôt, Sönke Szidat, and Patrick L. Hayes
                                    Atmos. Chem. Phys., 17, 9237–9259, https://doi.org/10.5194/acp-17-9237-2017, https://doi.org/10.5194/acp-17-9237-2017, 2017
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                                                Airborne particulate matter (PM) negatively impacts air quality in cities throughout the world. An important fraction of PM is organic aerosol. We have evaluated and developed several new models for secondary organic aerosol (SOA), which is formed from the chemical processing of gaseous precursors. Using our model results, we have quantified important SOA sources and precursors and also identified possible model parameterizations that could be used for air quality predictions.
                                            
                                            
                                        Shantanu H. Jathar, Christopher Heppding, Michael F. Link, Delphine K. Farmer, Ali Akherati, Michael J. Kleeman, Joost A. de Gouw, Patrick R. Veres, and James M. Roberts
                                    Atmos. Chem. Phys., 17, 8959–8970, https://doi.org/10.5194/acp-17-8959-2017, https://doi.org/10.5194/acp-17-8959-2017, 2017
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                                                Our work makes novel emissions measurements of isocyanic acid, a toxic gas, from a modern-day diesel engine and finds that diesel engines emit isocyanic acid but the emissions control devices do not enhance or destroy the isocyanic acid. Air quality model calculations suggest that diesel engines are possibly important sources of isocyanic acid in urban environments although the isocyanic acid levels are ten times lower than levels linked to adverse human health effects.
                                            
                                            
                                        Christopher Chan Miller, Daniel J. Jacob, Eloise A. Marais, Karen Yu, Katherine R. Travis, Patrick S. Kim, Jenny A. Fisher, Lei Zhu, Glenn M. Wolfe, Thomas F. Hanisco, Frank N. Keutsch, Jennifer Kaiser, Kyung-Eun Min, Steven S. Brown, Rebecca A. Washenfelder, Gonzalo González Abad, and Kelly Chance
                                    Atmos. Chem. Phys., 17, 8725–8738, https://doi.org/10.5194/acp-17-8725-2017, https://doi.org/10.5194/acp-17-8725-2017, 2017
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                                                The use of satellite glyoxal observations for estimating isoprene emissions has been limited by knowledge of the glyoxal yield from isoprene. We use SENEX aircraft observations over the southeast US to evaluate glyoxal yields from isoprene in a 3-D atmospheric model. The SENEX observations support a pathway for glyoxal formation in pristine regions that we propose here, which may have implications for improving isoprene emissions estimates from upcoming high-resolution geostationary satellites.
                                            
                                            
                                        Suzane S. de Sá, Brett B. Palm, Pedro Campuzano-Jost, Douglas A. Day, Matthew K. Newburn, Weiwei Hu, Gabriel Isaacman-VanWertz, Lindsay D. Yee, Ryan Thalman, Joel Brito, Samara Carbone, Paulo Artaxo, Allen H. Goldstein, Antonio O. Manzi, Rodrigo A. F. Souza, Fan Mei, John E. Shilling, Stephen R. Springston, Jian Wang, Jason D. Surratt, M. Lizabeth Alexander, Jose L. Jimenez, and Scot T. Martin
                                    Atmos. Chem. Phys., 17, 6611–6629, https://doi.org/10.5194/acp-17-6611-2017, https://doi.org/10.5194/acp-17-6611-2017, 2017
                            Rudra P. Pokhrel, Eric R. Beamesderfer, Nick L. Wagner, Justin M. Langridge, Daniel A. Lack, Thilina Jayarathne, Elizabeth A. Stone, Chelsea E. Stockwell, Robert J. Yokelson, and Shane M. Murphy
                                    Atmos. Chem. Phys., 17, 5063–5078, https://doi.org/10.5194/acp-17-5063-2017, https://doi.org/10.5194/acp-17-5063-2017, 2017
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                                                This study investigates enhancement of black carbon (BC) absorption in biomass burning emissions due to absorbing and non-absorbing coatings. The fraction of absorption due to BC, brown carbon (BrC), and lensing is estimated using different approaches. The similarities and differences between the results from these approaches are discussed. Absorption by BrC is shown to have good correlation with the elemental to organic carbon ratio (EC / OC) and AAE.
                                            
                                            
                                        Bin Yuan, Matthew M. Coggon, Abigail R. Koss, Carsten Warneke, Scott Eilerman, Jeff Peischl, Kenneth C. Aikin, Thomas B. Ryerson, and Joost A. de Gouw
                                    Atmos. Chem. Phys., 17, 4945–4956, https://doi.org/10.5194/acp-17-4945-2017, https://doi.org/10.5194/acp-17-4945-2017, 2017
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                                                In this study, we measured emissions of volatile organic compounds (VOCs) from concentrated animal feeding operations (CAFOs) using both mobile laboratory and aircraft measurements. We will use this data set to investigate chemical compositions of VOC emissions and sources apportionment for these VOC emissions in different facilities.
                                            
                                            
                                        Anne-Kathrin Bernhammer, Martin Breitenlechner, Frank N. Keutsch, and Armin Hansel
                                    Atmos. Chem. Phys., 17, 4053–4062, https://doi.org/10.5194/acp-17-4053-2017, https://doi.org/10.5194/acp-17-4053-2017, 2017
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                                                Isoprene is the predominant non-methane compound emitted by the biosphere. In the atmosphere oxidation by OH under low NOx produces isoprene hydroxy hydroperoxides (ISOPOOHs). This work has found an effective conversion of ISOPOOHs to volatile carbonyls on metal environmental simulation chamber walls. Likely catalyzed decomposition reactions also occur for other hydroxyl hydroperoxides on metal surfaces.
                                            
                                            
                                        Chathurika M. Rathnayake, Nervana Metwali, Thilina Jayarathne, Josh Kettler, Yuefan Huang, Peter S. Thorne, Patrick T. O'Shaughnessy, and Elizabeth A. Stone
                                    Atmos. Chem. Phys., 17, 2459–2475, https://doi.org/10.5194/acp-17-2459-2017, https://doi.org/10.5194/acp-17-2459-2017, 2017
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                                                Exposures to bioaerosols depend on their type, particle size, and concentration. While typically found in coarse particles (2.5–10 microns), pollens, fungal spores, and bacterial endotoxins decrease to less than 2.5 microns and simultaneously increase in concentration during rain events. These observations contrast the assumption that rain washes bioaerosols from the air and reduces allergen levels. Instead, population exposures to bioaerosols are expected to be enhanced during rain events.
                                            
                                            
                                        Ibrahim M. Al-Naiema and Elizabeth A. Stone
                                    Atmos. Chem. Phys., 17, 2053–2065, https://doi.org/10.5194/acp-17-2053-2017, https://doi.org/10.5194/acp-17-2053-2017, 2017
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                                                Molecular tracers have proven useful in estimating contributions of primary and biogenic secondary sources to atmospheric particulate matter but have lagged behind for anthropogenic secondary sources. This study takes a field-based approach to evaluate the detectability, specificity, and gas–particle partitioning of prospective anthropogenic SOA tracers. We conclude that a subset of species are likely useful tracers and are recommended for use in future source apportionment studies.
                                            
                                            
                                        Brian M. Lerner, Jessica B. Gilman, Kenneth C. Aikin, Elliot L. Atlas, Paul D. Goldan, Martin Graus, Roger Hendershot, Gabriel A. Isaacman-VanWertz, Abigail Koss, William C. Kuster, Richard A. Lueb, Richard J. McLaughlin, Jeff Peischl, Donna Sueper, Thomas B. Ryerson, Travis W. Tokarek, Carsten Warneke, Bin Yuan, and Joost A. de Gouw
                                    Atmos. Meas. Tech., 10, 291–313, https://doi.org/10.5194/amt-10-291-2017, https://doi.org/10.5194/amt-10-291-2017, 2017
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                                                Whole air sampling followed by analysis by gas chromatography is a common technique for characterization of trace volatile organic compounds in the atmosphere. We describe a new automated gas chromatograph–mass spectrograph which uses a Stirling cooler for sample preconcentration at −165 °C without the need for a cryogen such as liquid nitrogen. We also discuss potential sources of artifacts from our electropolished stainless steel sampling system and present results from two field campaigns.
                                            
                                            
                                        Havala O. T. Pye, Benjamin N. Murphy, Lu Xu, Nga L. Ng, Annmarie G. Carlton, Hongyu Guo, Rodney Weber, Petros Vasilakos, K. Wyat Appel, Sri Hapsari Budisulistiorini, Jason D. Surratt, Athanasios Nenes, Weiwei Hu, Jose L. Jimenez, Gabriel Isaacman-VanWertz, Pawel K. Misztal, and Allen H. Goldstein
                                    Atmos. Chem. Phys., 17, 343–369, https://doi.org/10.5194/acp-17-343-2017, https://doi.org/10.5194/acp-17-343-2017, 2017
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                                                We use a chemical transport model to examine how organic compounds in the atmosphere interact with water present in particles. Organic compounds themselves lead to water uptake, and organic compounds interact with water associated with inorganic compounds in the rural southeast atmosphere. Including interactions of organic compounds with water requires a treatment of nonideality to more accurately represent aerosol observations during the Southern Oxidant and Aerosol Study (SOAS) 2013.
                                            
                                            
                                        Emma L. D'Ambro, Ben H. Lee, Jiumeng Liu, John E. Shilling, Cassandra J. Gaston, Felipe D. Lopez-Hilfiker, Siegfried Schobesberger, Rahul A. Zaveri, Claudia Mohr, Anna Lutz, Zhenfa Zhang, Avram Gold, Jason D. Surratt, Jean C. Rivera-Rios, Frank N. Keutsch, and Joel A. Thornton
                                    Atmos. Chem. Phys., 17, 159–174, https://doi.org/10.5194/acp-17-159-2017, https://doi.org/10.5194/acp-17-159-2017, 2017
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                                                We studied the formation and properties of secondary organic aerosol produced from isoprene. We find that a significant fraction (~50 %) of the mass is composed of low-volatility, highly oxidized compounds such as C5H12O6. A significant fraction of the remainder appears to be in the form of oligomeric material. Adding NOx maintained or decreased SOA yields while increasing the fraction of low-volatility material, possibly due to oligomers.
                                            
                                            
                                        Marie Ila Gosselin, Chathurika M. Rathnayake, Ian Crawford, Christopher Pöhlker, Janine Fröhlich-Nowoisky, Beatrice Schmer, Viviane R. Després, Guenter Engling, Martin Gallagher, Elizabeth Stone, Ulrich Pöschl, and J. Alex Huffman
                                    Atmos. Chem. Phys., 16, 15165–15184, https://doi.org/10.5194/acp-16-15165-2016, https://doi.org/10.5194/acp-16-15165-2016, 2016
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                                                We present an analysis of bioaerosol measurements using two real-time fluorescence instruments in combination with molecular tracer techniques for quantifying airborne fungal spores in a semi-arid forest. Both techniques provide fungal spore concentrations of the order of 104 m−3 and up to 30 % of particle mass. Rainy periods exhibited higher concentrations and stronger correlations between fluorescent bioparticle and molecular tracer measurements. Fungal culture results are also presented.
                                            
                                            
                                        Yaping Zhang, Brent J. Williams, Allen H. Goldstein, Kenneth S. Docherty, and Jose L. Jimenez
                                    Atmos. Meas. Tech., 9, 5637–5653, https://doi.org/10.5194/amt-9-5637-2016, https://doi.org/10.5194/amt-9-5637-2016, 2016
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                                                The binning method provides an alternate way to process GC–MS data in a very fast manner. It only takes a very small portion of time (days versus years) compared to the traditional GC–MS data analysis method (peak identification and integration). Furthermore, the binning method can also be applied to any data set from a measurement (mass spectrometry, spectroscopy, etc.) with additional separations (volatility, polarity, size, etc.).
                                            
                                            
                                        Omar Amador-Muñoz, Pawel K. Misztal, Robin Weber, David R. Worton, Haofei Zhang, Greg Drozd, and Allen H. Goldstein
                                    Atmos. Meas. Tech., 9, 5315–5329, https://doi.org/10.5194/amt-9-5315-2016, https://doi.org/10.5194/amt-9-5315-2016, 2016
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                                                Proton transfer reaction mass spectrometry (PTR-MS) was used to detect n-alkanes that generally have a lower proton affinity than water and therefore proton transfer (PT) by reaction with H3O+ is not an effective mechanism for their detection. In this study, we developed a method using a conventional PTR-MS to detect n-alkanes by optimizing ion source and drift tube conditions to vary the relative amounts of different primary ions (H3O+, O2+, NO+) in the reaction chamber (drift tube).
                                            
                                            
                                        Chelsea E. Stockwell, Thilina Jayarathne, Mark A. Cochrane, Kevin C. Ryan, Erianto I. Putra, Bambang H. Saharjo, Ati D. Nurhayati, Israr Albar, Donald R. Blake, Isobel J. Simpson, Elizabeth A. Stone, and Robert J. Yokelson
                                    Atmos. Chem. Phys., 16, 11711–11732, https://doi.org/10.5194/acp-16-11711-2016, https://doi.org/10.5194/acp-16-11711-2016, 2016
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                                                We present the first or rare field measurements of emission factors for Indonesian peat fires made in Borneo during the 2015 El Niño. The data include up to 90 gases, aerosol mass, and aerosol optical properties at two wavelengths (405 and 870 nm). Brown carbon dominates aerosol absorption, revisions to previous values for greenhouse gas emissions are supported and air toxics are assessed.
                                            
                                            
                                        Weiwei Hu, Brett B. Palm, Douglas A. Day, Pedro Campuzano-Jost, Jordan E. Krechmer, Zhe Peng, Suzane S. de Sá, Scot T. Martin, M. Lizabeth Alexander, Karsten Baumann, Lina Hacker, Astrid Kiendler-Scharr, Abigail R. Koss, Joost A. de Gouw, Allen H. Goldstein, Roger Seco, Steven J. Sjostedt, Jeong-Hoo Park, Alex B. Guenther, Saewung Kim, Francesco Canonaco, André S. H. Prévôt, William H. Brune, and Jose L. Jimenez
                                    Atmos. Chem. Phys., 16, 11563–11580, https://doi.org/10.5194/acp-16-11563-2016, https://doi.org/10.5194/acp-16-11563-2016, 2016
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                                                IEPOX-SOA is biogenically derived secondary organic aerosol under anthropogenic influence, which has been shown to comprise a substantial fraction of OA globally. We investigated the lifetime of ambient IEPOX-SOA in the SE US and Amazonia, with an oxidation flow reactor and thermodenuder coupled with MS-based instrumentation. The low volatility and long lifetime of IEPOX-SOA against OH radicals' oxidation (> 2 weeks) was observed, which can help to constrain OA impact on air quality and climate.
                                            
                                            
                                        Jason M. St. Clair, Jean C. Rivera-Rios, John D. Crounse, Eric Praske, Michelle J. Kim, Glenn M. Wolfe, Frank N. Keutsch, Paul O. Wennberg, and Thomas F. Hanisco
                                    Atmos. Meas. Tech., 9, 4561–4568, https://doi.org/10.5194/amt-9-4561-2016, https://doi.org/10.5194/amt-9-4561-2016, 2016
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                                                Global isoprene emissions are the largest source of atmospheric non-methane hydrocarbons. Lab results show that ISOPOOH, a low-NOx isoprene oxidation product, can decompose on instrument surfaces to form high-NOx isoprene oxidation products, causing misinterpretation of oxidation conditions. This study investigated the potential formaldehyde artifact from ISOPOOH for the NASA ISAF instrument, and found that it does not significantly affect the accuracy of the ISAF field measurements.
                                            
                                            
                                        Chelsea E. Stockwell, Ted J. Christian, J. Douglas Goetz, Thilina Jayarathne, Prakash V. Bhave, Puppala S. Praveen, Sagar Adhikari, Rashmi Maharjan, Peter F. DeCarlo, Elizabeth A. Stone, Eri Saikawa, Donald R. Blake, Isobel J. Simpson, Robert J. Yokelson, and Arnico K. Panday
                                    Atmos. Chem. Phys., 16, 11043–11081, https://doi.org/10.5194/acp-16-11043-2016, https://doi.org/10.5194/acp-16-11043-2016, 2016
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                                                We present the first, or rare, field measurements in South Asia of emission factors for up to 80 gases (pollutants, greenhouse gases, and precursors) and black carbon and aerosol optical properties at 405 and 870 nm for many previously under-sampled sources that are important in developing countries such as cooking with dung and wood, garbage and crop residue burning, brick kilns, motorcycles, generators and pumps, etc. Brown carbon contributes significantly to total aerosol absorption.
                                            
                                            
                                        Matthieu Riva, Thais Da Silva Barbosa, Ying-Hsuan Lin, Elizabeth A. Stone, Avram Gold, and Jason D. Surratt
                                    Atmos. Chem. Phys., 16, 11001–11018, https://doi.org/10.5194/acp-16-11001-2016, https://doi.org/10.5194/acp-16-11001-2016, 2016
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                                                Formation of organosulfates (OSs) in secondary organic aerosol from the photooxidation of alkanes is reported from smog chamber experiments. Effects of  acidity and relative humidity on OS formation were examined. Most of the OSs identified could be explained by formation of gaseous epoxide and/or hydroperoxide precursors with subsequent acid-catalyzed multiphase chemistry onto sulfate aerosol. The OSs identified here were also observed and quantified in aerosols collected in two urban areas.
                                            
                                            
                                        Pawel K. Misztal, Jeremy C. Avise, Thomas Karl, Klaus Scott, Haflidi H. Jonsson, Alex B. Guenther, and Allen H. Goldstein
                                    Atmos. Chem. Phys., 16, 9611–9628, https://doi.org/10.5194/acp-16-9611-2016, https://doi.org/10.5194/acp-16-9611-2016, 2016
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                                                In this study, for the first time regional BVOC models are compared with direct regional measurements of fluxes from aircraft, allowing assessment of model accuracy at scales relevant to air quality modeling. We directly assess modeled isoprene emission inventories which are important for regional air quality simulations of ozone and secondary particle concentrations.
                                            
                                            
                                        Rudra P. Pokhrel, Nick L. Wagner, Justin M. Langridge, Daniel A. Lack, Thilina Jayarathne, Elizabeth A. Stone, Chelsea E. Stockwell, Robert J. Yokelson, and Shane M. Murphy
                                    Atmos. Chem. Phys., 16, 9549–9561, https://doi.org/10.5194/acp-16-9549-2016, https://doi.org/10.5194/acp-16-9549-2016, 2016
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                                                This paper gives first multi-wavelength estimates of SSA and AAE of emissions from combustion of Indonesian peat. In addition, it demonstrates that SSA of biomass burning emissions can be parameterized with EC / (EC+OC) and that this parameterization is quantitatively superior to previously published parameterizations based on MCE. It also shows that EC / (EC+OC) parameterization accurately predicts SSA during the first few hours of aging of a biomass burning plume.
                                            
                                            
                                        J. Kaiser, K. M. Skog, K. Baumann, S. B. Bertman, S. B. Brown, W. H. Brune, J. D. Crounse, J. A. de Gouw, E. S. Edgerton, P. A. Feiner, A. H. Goldstein, A. Koss, P. K. Misztal, T. B. Nguyen, K. F. Olson, J. M. St. Clair, A. P. Teng, S. Toma, P. O. Wennberg, R. J. Wild, L. Zhang, and F. N. Keutsch
                                    Atmos. Chem. Phys., 16, 9349–9359, https://doi.org/10.5194/acp-16-9349-2016, https://doi.org/10.5194/acp-16-9349-2016, 2016
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                                                OH reactivity can be used to assess the amount of reactive carbon in an air mass. “Missing” reactivity is commonly found in forested environments and is attributed to either direct emissions of unmeasured volatile organic compounds or to unmeasured/underpredicted oxidation products. Using a box model and measurements from the 2013 SOAS campaign, we find only small discrepancies in measured and calculated reactivity. Our results suggest the discrepancies stem from unmeasured direct emissions.
                                            
                                            
                                        Carsten Warneke, Michael Trainer, Joost A. de Gouw, David D. Parrish, David W. Fahey, A. R. Ravishankara, Ann M. Middlebrook, Charles A. Brock, James M. Roberts, Steven S. Brown, Jonathan A. Neuman, Brian M. Lerner, Daniel Lack, Daniel Law, Gerhard Hübler, Iliana Pollack, Steven Sjostedt, Thomas B. Ryerson, Jessica B. Gilman, Jin Liao, John Holloway, Jeff Peischl, John B. Nowak, Kenneth C. Aikin, Kyung-Eun Min, Rebecca A. Washenfelder, Martin G. Graus, Mathew Richardson, Milos Z. Markovic, Nick L. Wagner, André Welti, Patrick R. Veres, Peter Edwards, Joshua P. Schwarz, Timothy Gordon, William P. Dube, Stuart A. McKeen, Jerome Brioude, Ravan Ahmadov, Aikaterini Bougiatioti, Jack J. Lin, Athanasios Nenes, Glenn M. Wolfe, Thomas F. Hanisco, Ben H. Lee, Felipe D. Lopez-Hilfiker, Joel A. Thornton, Frank N. Keutsch, Jennifer Kaiser, Jingqiu Mao, and Courtney D. Hatch
                                    Atmos. Meas. Tech., 9, 3063–3093, https://doi.org/10.5194/amt-9-3063-2016, https://doi.org/10.5194/amt-9-3063-2016, 2016
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                                                In this paper we describe the experimental approach, the science goals and early results of the NOAA SENEX campaign, which was focused on studying the interactions between biogenic and anthropogenic emissions to form secondary pollutants.
During SENEX, the NOAA WP-3D aircraft conducted 20 research flights between 27 May and 10 July 2013 based out of Smyrna, TN. The SENEX flights included day- and nighttime flights in the Southeast as well as flights over areas with intense shale gas extraction.
                                            
                                            
                                        Abigail R. Koss, Carsten Warneke, Bin Yuan, Matthew M. Coggon, Patrick R. Veres, and Joost A. de Gouw
                                    Atmos. Meas. Tech., 9, 2909–2925, https://doi.org/10.5194/amt-9-2909-2016, https://doi.org/10.5194/amt-9-2909-2016, 2016
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                                                Using laboratory and field experiments, we have explored how the technique of NO+ chemical ionization mass spectrometry can be used to measure volatile organic compounds (VOCs) in the troposphere. Results include the design and operation of the instrument, an evaluation of the technique’s utility for atmospheric measurement, and a guide for data interpretation. Use of this technique will improve our understanding of VOC chemistry.
                                            
                                            
                                        Amy P. Sullivan, Natasha Hodas, Barbara J. Turpin, Kate Skog, Frank N. Keutsch, Stefania Gilardoni, Marco Paglione, Matteo Rinaldi, Stefano Decesari, Maria Cristina Facchini, Laurent Poulain, Hartmut Herrmann, Alfred Wiedensohler, Eiko Nemitz, Marsailidh M. Twigg, and Jeffrey L. Collett Jr.
                                    Atmos. Chem. Phys., 16, 8095–8108, https://doi.org/10.5194/acp-16-8095-2016, https://doi.org/10.5194/acp-16-8095-2016, 2016
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                                                This paper presents the results from our measurements and approach for the investigation of aqueous secondary organic aerosol (aqSOA) formation in the ambient atmosphere.  When local aqSOA formation was observed, a correlation of water-soluble organic carbon with organic aerosol, aerosol liquid water, relative humidity, and aerosol nitrate was found.  Key factors of local aqSOA production include air mass stagnation, formation of local nitrate overnight, and significant amounts of ammonia.
                                            
                                            
                                        Bin Yuan, Abigail Koss, Carsten Warneke, Jessica B. Gilman, Brian M. Lerner, Harald Stark, and Joost A. de Gouw
                                    Atmos. Meas. Tech., 9, 2735–2752, https://doi.org/10.5194/amt-9-2735-2016, https://doi.org/10.5194/amt-9-2735-2016, 2016
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                                                We present the development of a hydronium (H3O+) time of flight chemical ionization mass spectrometer (H3O+ ToF-CIMS). We characterize the humidity dependence of the reagent ions and VOC signals in details. The low mass cutoff issue of RF-only quadrupole leads to unusual humidity dependence of reagent ions. The new H3O+ ToF-CIMS was successfully deployed on the NOAA WP-3D research aircraft for the SONGNEX campaign in 2015 and some initial results from the SONGNEX campaign are presented.
                                            
                                            
                                        Luping Su, Edward G. Patton, Jordi Vilà-Guerau de Arellano, Alex B. Guenther, Lisa Kaser, Bin Yuan, Fulizi Xiong, Paul B. Shepson, Li Zhang, David O. Miller, William H. Brune, Karsten Baumann, Eric Edgerton, Andrew Weinheimer, Pawel K. Misztal, Jeong-Hoo Park, Allen H. Goldstein, Kate M. Skog, Frank N. Keutsch, and John E. Mak
                                    Atmos. Chem. Phys., 16, 7725–7741, https://doi.org/10.5194/acp-16-7725-2016, https://doi.org/10.5194/acp-16-7725-2016, 2016
                            Paul S. Romer, Kaitlin C. Duffey, Paul J. Wooldridge, Hannah M. Allen, Benjamin R. Ayres, Steven S. Brown, William H. Brune, John D. Crounse, Joost de Gouw, Danielle C. Draper, Philip A. Feiner, Juliane L. Fry, Allen H. Goldstein, Abigail Koss, Pawel K. Misztal, Tran B. Nguyen, Kevin Olson, Alex P. Teng, Paul O. Wennberg, Robert J. Wild, Li Zhang, and Ronald C. Cohen
                                    Atmos. Chem. Phys., 16, 7623–7637, https://doi.org/10.5194/acp-16-7623-2016, https://doi.org/10.5194/acp-16-7623-2016, 2016
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                                                The lifetime of nitrogen oxides (NOx) is evaluated by analysis of field measurements from the southeastern United States. At warm temperatures in the daytime boundary layer, NOx interconverts rapidly with both PAN and alkyl and multifunctional nitrates (RONO2), and the relevant lifetime is the combined lifetime of these three classes. We find that the production of RONO2, followed by hydrolysis to produce nitric acid, is the dominant pathway for NOx removal in an isoprene dominated forest.
                                            
                                            
                                        Amber M. Ortega, Patrick L. Hayes, Zhe Peng, Brett B. Palm, Weiwei Hu, Douglas A. Day, Rui Li, Michael J. Cubison, William H. Brune, Martin Graus, Carsten Warneke, Jessica B. Gilman, William C. Kuster, Joost de Gouw, Cándido Gutiérrez-Montes, and Jose L. Jimenez
                                    Atmos. Chem. Phys., 16, 7411–7433, https://doi.org/10.5194/acp-16-7411-2016, https://doi.org/10.5194/acp-16-7411-2016, 2016
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                                                An oxidation flow reactor (OFR) was deployed to study secondary organic aerosol (SOA) formation and aging of urban emissions at a wide range of OH exposures during the CalNex campaign in Pasadena, CA, in 2010. Results include linking SOA formation to short-lived reactive compounds, similar elemental composition of reactor-aged emissions to atmospheric aging, changes in OA mass due to condensation of oxidized gas-phase species and heterogeneous oxidation of particle-phase species.
                                            
                                            
                                        Jenny A. Fisher, Daniel J. Jacob, Katherine R. Travis, Patrick S. Kim, Eloise A. Marais, Christopher Chan Miller, Karen Yu, Lei Zhu, Robert M. Yantosca, Melissa P. Sulprizio, Jingqiu Mao, Paul O. Wennberg, John D. Crounse, Alex P. Teng, Tran B. Nguyen, Jason M. St. Clair, Ronald C. Cohen, Paul Romer, Benjamin A. Nault, Paul J. Wooldridge, Jose L. Jimenez, Pedro Campuzano-Jost, Douglas A. Day, Weiwei Hu, Paul B. Shepson, Fulizi Xiong, Donald R. Blake, Allen H. Goldstein, Pawel K. Misztal, Thomas F. Hanisco, Glenn M. Wolfe, Thomas B. Ryerson, Armin Wisthaler, and Tomas Mikoviny
                                    Atmos. Chem. Phys., 16, 5969–5991, https://doi.org/10.5194/acp-16-5969-2016, https://doi.org/10.5194/acp-16-5969-2016, 2016
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                                                We use new airborne and ground-based observations from two summer 2013 campaigns in the southeastern US, interpreted with a chemical transport model, to understand the impact of isoprene and monoterpene chemistry on the atmospheric NOx budget via production of organic nitrates (RONO2). We find that a diversity of species contribute to observed RONO2. Our work implies that the NOx sink to RONO2 production is only sensitive to NOx emissions in regions where they are already low.
                                            
                                            
                                        Sri Hapsari Budisulistiorini, Karsten Baumann, Eric S. Edgerton, Solomon T. Bairai, Stephen Mueller, Stephanie L. Shaw, Eladio M. Knipping, Avram Gold, and Jason D. Surratt
                                    Atmos. Chem. Phys., 16, 5171–5189, https://doi.org/10.5194/acp-16-5171-2016, https://doi.org/10.5194/acp-16-5171-2016, 2016
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                                                A year-long near-real-time characterization of non-refractory submicron aerosol (NR-PM1) was conducted at an urban (Atlanta, Georgia, in 2012) and rural (Look Rock, Tennessee, in 2013) site in the southeastern US using the Aerodyne Aerosol Chemical Speciation Monitor, collocated with established air-monitoring network measurements, to identify sources of organic aerosol (OA). Further, high-volume filter samples were collected for measurements of OA tracers by offline mass spectrometry tools.
                                            
                                            
                                        Weruka Rattanavaraha, Kevin Chu, Sri Hapsari Budisulistiorini, Matthieu Riva, Ying-Hsuan Lin, Eric S. Edgerton, Karsten Baumann, Stephanie L. Shaw, Hongyu Guo, Laura King, Rodney J. Weber, Miranda E. Neff, Elizabeth A. Stone, John H. Offenberg, Zhenfa Zhang, Avram Gold, and Jason D. Surratt
                                    Atmos. Chem. Phys., 16, 4897–4914, https://doi.org/10.5194/acp-16-4897-2016, https://doi.org/10.5194/acp-16-4897-2016, 2016
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                                                The mechanisms by which specific anthropogenic pollutants enhance isoprene SOA in ambient PM2.5 remain unclear. As one aspect of an investigation to examine how anthropogenic pollutants influence isoprene-derived SOA formation, high-volume PM2.5 filter samples were collected from Birmingham, AL, during the 2013 Southern Oxidant and Aerosol Study (SOAS). Isoprene SOA tracers were measured from these samples and compared to gas and aerosol data collected from the SEARCH network.
                                            
                                            
                                        S. T. Martin, P. Artaxo, L. A. T. Machado, A. O. Manzi, R. A. F. Souza, C. Schumacher, J. Wang, M. O. Andreae, H. M. J. Barbosa, J. Fan, G. Fisch, A. H. Goldstein, A. Guenther, J. L. Jimenez, U. Pöschl, M. A. Silva Dias, J. N. Smith, and M. Wendisch
                                    Atmos. Chem. Phys., 16, 4785–4797, https://doi.org/10.5194/acp-16-4785-2016, https://doi.org/10.5194/acp-16-4785-2016, 2016
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                                                The Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) Experiment took place in central Amazonia throughout 2014 and 2015. The experiment focused on the complex links among vegetation, atmospheric chemistry, and aerosol production on the one hand and their connections to aerosols, clouds, and precipitation on the other, especially when altered by urban pollution. This article serves as an introduction to the special issue of publications presenting findings of this experiment.
                                            
                                            
                                        Brent J. Williams, Yaping Zhang, Xiaochen Zuo, Raul E. Martinez, Michael J. Walker, Nathan M. Kreisberg, Allen H. Goldstein, Kenneth S. Docherty, and Jose L. Jimenez
                                    Atmos. Meas. Tech., 9, 1569–1586, https://doi.org/10.5194/amt-9-1569-2016, https://doi.org/10.5194/amt-9-1569-2016, 2016
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                                                The thermal desorption aerosol gas chromatograph (TAG) has been used for in situ measurements of organic marker compounds to identify atmospheric particle sources and transformation processes. Here we identify that inorganic aerosol components (e.g., nitrate and sulfate) and highly oxygenated organic components experience thermal decomposition upon sample heating. This thermal decomposition signal in the TAG system is investigated through laboratory and field data.
                                            
                                            
                                        Min Zhong, Eri Saikawa, Yang Liu, Vaishali Naik, Larry W. Horowitz, Masayuki Takigawa, Yu Zhao, Neng-Huei Lin, and Elizabeth A. Stone
                                    Geosci. Model Dev., 9, 1201–1218, https://doi.org/10.5194/gmd-9-1201-2016, https://doi.org/10.5194/gmd-9-1201-2016, 2016
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                                                Large discrepancies exist among emission inventories (e.g., REAS and EDGAR) at the provincial level in China. We use WRF-Chem to evaluate the impact of the difference in existing emission inventories and find that emissions inputs significantly affect our air pollutant simulation results. Our study highlights the importance of constraining emissions at the provincial level for regional air quality modeling over East Asia.
                                            
                                            
                                        Markus Müller, Bruce E. Anderson, Andreas J. Beyersdorf, James H. Crawford, Glenn S. Diskin, Philipp Eichler, Alan Fried, Frank N. Keutsch, Tomas Mikoviny, Kenneth L. Thornhill, James G. Walega, Andrew J. Weinheimer, Melissa Yang, Robert J. Yokelson, and Armin Wisthaler
                                    Atmos. Chem. Phys., 16, 3813–3824, https://doi.org/10.5194/acp-16-3813-2016, https://doi.org/10.5194/acp-16-3813-2016, 2016
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                                                Atmospheric emissions from small forest fires and their impact on regional air quality are still poorly characterized. We used an instrumented NASA P-3B aircraft to study emissions from a small forest understory fire in Georgia (USA) and to investigate chemical transformations in the fire plume in the 1 h downwind region. A state-of-the-art chemical model was able to accurately simulate key chemical processes in the aging plume.
                                            
                                            
                                        G. M. Wolfe, J. Kaiser, T. F. Hanisco, F. N. Keutsch, J. A. de Gouw, J. B. Gilman, M. Graus, C. D. Hatch, J. Holloway, L. W. Horowitz, B. H. Lee, B. M. Lerner, F. Lopez-Hilifiker, J. Mao, M. R. Marvin, J. Peischl, I. B. Pollack, J. M. Roberts, T. B. Ryerson, J. A. Thornton, P. R. Veres, and C. Warneke
                                    Atmos. Chem. Phys., 16, 2597–2610, https://doi.org/10.5194/acp-16-2597-2016, https://doi.org/10.5194/acp-16-2597-2016, 2016
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                                                This study uses airborne trace gas observations acquired over the southeast US to examine how both natural (isoprene) and anthropogenic (NOx) emissions influence the production of formaldehyde (HCHO). We find a 3-fold increase in HCHO yield between rural and polluted environments. State-of-the-science chemical mechanisms are generally able to reproduce this behavior. These results add confidence to global hydrocarbon emission inventories constrained by spaceborne HCHO observations.
                                            
                                            
                                        Bin Yuan, John Liggio, Jeremy Wentzell, Shao-Meng Li, Harald Stark, James M. Roberts, Jessica Gilman, Brian Lerner, Carsten Warneke, Rui Li, Amy Leithead, Hans D. Osthoff, Robert Wild, Steven S. Brown, and Joost A. de Gouw
                                    Atmos. Chem. Phys., 16, 2139–2153, https://doi.org/10.5194/acp-16-2139-2016, https://doi.org/10.5194/acp-16-2139-2016, 2016
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                                                We describe high-resolution measurements of nitrated phenols using a time-of-flight chemical ionization mass spectrometer (ToF-CIMS). Strong diurnal profiles were observed for nitrated phenols, with concentration maxima at night. Box model simulations were able to reproduce the measured nitrated phenols.
                                            
                                            
                                        A. W. H. Chan, N. M. Kreisberg, T. Hohaus, P. Campuzano-Jost, Y. Zhao, D. A. Day, L. Kaser, T. Karl, A. Hansel, A. P. Teng, C. R. Ruehl, D. T. Sueper, J. T. Jayne, D. R. Worsnop, J. L. Jimenez, S. V. Hering, and A. H. Goldstein
                                    Atmos. Chem. Phys., 16, 1187–1205, https://doi.org/10.5194/acp-16-1187-2016, https://doi.org/10.5194/acp-16-1187-2016, 2016
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                                                Using a novel instrument, we have made measurements of organic compounds that can exist as a gas or particle in the rural atmosphere. Through hourly measurements, we have identified the sources and atmospheric processes of these compounds, which are important for modeling the climate and health impact of these emissions.
                                            
                                            
                                        E. W. Butt, A. Rap, A. Schmidt, C. E. Scott, K. J. Pringle, C. L. Reddington, N. A. D. Richards, M. T. Woodhouse, J. Ramirez-Villegas, H. Yang, V. Vakkari, E. A. Stone, M. Rupakheti, P. S. Praveen, P. G. van Zyl, J. P. Beukes, M. Josipovic, E. J. S. Mitchell, S. M. Sallu, P. M. Forster, and D. V. Spracklen
                                    Atmos. Chem. Phys., 16, 873–905, https://doi.org/10.5194/acp-16-873-2016, https://doi.org/10.5194/acp-16-873-2016, 2016
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                                                We estimate the impact of residential emissions (cooking and heating) on atmospheric aerosol, human health, and climate. We find large contributions to annual mean ambient PM2.5 in residential sources regions resulting in significant but uncertain global premature mortality when key uncertainties in emission flux are considered. We show that residential emissions exert an uncertain global radiative effect and suggest more work is needed to characterise residential emissions climate importance.
                                            
                                            
                                        R. J. Wild, P. M. Edwards, T. S. Bates, R. C. Cohen, J. A. de Gouw, W. P. Dubé, J. B. Gilman, J. Holloway, J. Kercher, A. R. Koss, L. Lee, B. M. Lerner, R. McLaren, P. K. Quinn, J. M. Roberts, J. Stutz, J. A. Thornton, P. R. Veres, C. Warneke, E. Williams, C. J. Young, B. Yuan, K. J. Zarzana, and S. S. Brown
                                    Atmos. Chem. Phys., 16, 573–583, https://doi.org/10.5194/acp-16-573-2016, https://doi.org/10.5194/acp-16-573-2016, 2016
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                                                High wintertime ozone levels have been observed in the Uintah Basin, Utah, a sparsely populated rural region with intensive oil and gas operations. The reactive nitrogen budget plays an important role in tropospheric ozone formation, and we find that nighttime chemistry has a large effect on its partitioning. Much of the oxidation of reactive nitrogen during a high-ozone year occurred via heterogeneous uptake onto aerosol at night, keeping NOx at concentrations comparable to a low-ozone year.
                                            
                                            
                                        C. L. Blanchard, G. M. Hidy, S. Shaw, K. Baumann, and E. S. Edgerton
                                    Atmos. Chem. Phys., 16, 215–238, https://doi.org/10.5194/acp-16-215-2016, https://doi.org/10.5194/acp-16-215-2016, 2016
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                                                Fifteen years of gas and particle measurements at eight monitoring sites comprising the Southeastern Aerosol Research and Characterization (SEARCH) network offer insights into the sources of organic aerosol in the southeastern United States. Between 1999 and 2013, mean organic aerosol concentrations declined due to decreasing particle emissions from motor vehicles and to less secondary organic aerosol with declining emissions of sulfur dioxide, nitrogen oxides, and volatile organic compounds.
                                            
                                            
                                        J. B. Gilman, B. M. Lerner, W. C. Kuster, P. D. Goldan, C. Warneke, P. R. Veres, J. M. Roberts, J. A. de Gouw, I. R. Burling, and R. J. Yokelson
                                    Atmos. Chem. Phys., 15, 13915–13938, https://doi.org/10.5194/acp-15-13915-2015, https://doi.org/10.5194/acp-15-13915-2015, 2015
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                                                A comprehensive suite of instruments was used to quantify the emissions of over 200 organic and inorganic gases from 56 laboratory burns of 18 different biomass fuel types common in the southeastern, southwestern, or northern United States.  Emission ratios relative to carbon monoxide (CO) are used to characterize the composition of gases emitted by mass; OH reactivity; and potential secondary organic aerosol (SOA) precursors for the three different U.S. fuel regions presented here.
                                            
                                            
                                        J. Timkovsky, A. W. H. Chan, T. Dorst, A. H. Goldstein, B. Oyama, and R. Holzinger
                                    Atmos. Meas. Tech., 8, 5177–5187, https://doi.org/10.5194/amt-8-5177-2015, https://doi.org/10.5194/amt-8-5177-2015, 2015
                            S. J. Lawson, M. D. Keywood, I. E. Galbally, J. L. Gras, J. M. Cainey, M. E. Cope, P. B. Krummel, P. J. Fraser, L. P. Steele, S. T. Bentley, C. P. Meyer, Z. Ristovski, and A. H. Goldstein
                                    Atmos. Chem. Phys., 15, 13393–13411, https://doi.org/10.5194/acp-15-13393-2015, https://doi.org/10.5194/acp-15-13393-2015, 2015
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                                                Biomass burning (BB) plumes were opportunistically measured at the Cape Grim Baseline Station in Tasmania, Australia. We provide a unique set of trace gas and particle emission factors for temperate Australian coastal heathland fires, and attribute a major short-lived enhancement in emission ratios to a minor rainfall event. The ability of BB particles to act as cloud condensation nuclei, and the contribution of BB emissions to observed particle growth and ozone enhancements are discussed.
                                            
                                            
                                        B. R. Ayres, H. M. Allen, D. C. Draper, S. S. Brown, R. J. Wild, J. L. Jimenez, D. A. Day, P. Campuzano-Jost, W. Hu, J. de Gouw, A. Koss, R. C. Cohen, K. C. Duffey, P. Romer, K. Baumann, E. Edgerton, S. Takahama, J. A. Thornton, B. H. Lee, F. D. Lopez-Hilfiker, C. Mohr, P. O. Wennberg, T. B. Nguyen, A. Teng, A. H. Goldstein, K. Olson, and J. L. Fry
                                    Atmos. Chem. Phys., 15, 13377–13392, https://doi.org/10.5194/acp-15-13377-2015, https://doi.org/10.5194/acp-15-13377-2015, 2015
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                                                This paper reports atmospheric gas- and aerosol-phase field measurements from the southeastern United States in summer 2013 to demonstrate that the oxidation of biogenic volatile organic compounds by nitrate radical produces a substantial amount of secondary organic aerosol in this region. This process, driven largely by monoterpenes, results in a comparable aerosol nitrate production rate to inorganic nitrate formation by heterogeneous uptake of HNO3 onto dust particles.
                                            
                                            
                                        A. Guha, D. R. Gentner, R. J. Weber, R. Provencal, and A. H. Goldstein
                                    Atmos. Chem. Phys., 15, 12043–12063, https://doi.org/10.5194/acp-15-12043-2015, https://doi.org/10.5194/acp-15-12043-2015, 2015
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                                                We perform a positive matrix factorization (PMF)-based source apportionment by combining GHG measurements with coincident VOC measurements in the San Joaquin Valley of California. Using VOCs as source tracers, we identify dairies and livestock as major sources of CH4 and N2O in the region. Agriculture is a significant source of N2O enhancements too, while vehicle emissions are found to be a negligible source of N2O. The findings are relevant to the state’s GHG inventory verification process.
                                            
                                            
                                        W. W. Hu, P. Campuzano-Jost, B. B. Palm, D. A. Day, A. M. Ortega, P. L. Hayes, J. E. Krechmer, Q. Chen, M. Kuwata, Y. J. Liu, S. S. de Sá, K. McKinney, S. T. Martin, M. Hu, S. H. Budisulistiorini, M. Riva, J. D. Surratt, J. M. St. Clair, G. Isaacman-Van Wertz, L. D. Yee, A. H. Goldstein, S. Carbone, J. Brito, P. Artaxo, J. A. de Gouw, A. Koss, A. Wisthaler, T. Mikoviny, T. Karl, L. Kaser, W. Jud, A. Hansel, K. S. Docherty, M. L. Alexander, N. H. Robinson, H. Coe, J. D. Allan, M. R. Canagaratna, F. Paulot, and J. L. Jimenez
                                    Atmos. Chem. Phys., 15, 11807–11833, https://doi.org/10.5194/acp-15-11807-2015, https://doi.org/10.5194/acp-15-11807-2015, 2015
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                                                This work summarized all the studies reporting isoprene epoxydiols-derived secondary organic aerosol (IEPOX-SOA) measured globally by aerosol mass spectrometer and compare them with modeled gas-phase IEPOX, with results suggestive of the importance of IEPOX-SOA for regional and global OA budgets. A real-time tracer of IEPOX-SOA is thoroughly evaluated for the first time by combing multiple field and chamber studies. A quick and easy empirical method on IEPOX-SOA estimation is also presented.
                                            
                                            
                                        F. Xiong, K. M. McAvey, K. A. Pratt, C. J. Groff, M. A. Hostetler, M. A. Lipton, T. K. Starn, J. V. Seeley, S. B. Bertman, A. P. Teng, J. D. Crounse, T. B. Nguyen, P. O. Wennberg, P. K. Misztal, A. H. Goldstein, A. B. Guenther, A. R. Koss, K. F. Olson, J. A. de Gouw, K. Baumann, E. S. Edgerton, P. A. Feiner, L. Zhang, D. O. Miller, W. H. Brune, and P. B. Shepson
                                    Atmos. Chem. Phys., 15, 11257–11272, https://doi.org/10.5194/acp-15-11257-2015, https://doi.org/10.5194/acp-15-11257-2015, 2015
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                                                Hydroxynitrates from isoprene oxidation were quantified both in the laboratory and through field studies. The yield of hydroxynitrates 9(+4/-3)% derived from chamber experiments was applied in a zero-dimensional model to simulate the production and loss of isoprene hydroxynitrates in an ambient environment during the 2013 Southern Oxidant and Aerosol Study (SOAS). NOx was determined to be the limiting factor for the formation of isoprene hydroxynitrates during SOAS.
                                            
                                            
                                        C. Huang, H. L. Wang, L. Li, Q. Wang, Q. Lu, J. A. de Gouw, M. Zhou, S. A. Jing, J. Lu, and C. H. Chen
                                    Atmos. Chem. Phys., 15, 11081–11096, https://doi.org/10.5194/acp-15-11081-2015, https://doi.org/10.5194/acp-15-11081-2015, 2015
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                                                SOA formations from vehicle exhausts and gas evaporation contribute 40% and 60% of total organic aerosols observed in summer and winter in urban Shanghai. Diesel vehicles, which accounted for less than 20% of vehicle kilometers of travel, contribute the most to vehicular POA emissions and SOA production in urban Shanghai. Intermediate-volatile organic compounds (IVOCs) in vehicle exhausts contribute greatly to SOA formation in the urban atmosphere of China.
                                            
                                            
                                        H. M. Allen, D. C. Draper, B. R. Ayres, A. Ault, A. Bondy, S. Takahama, R. L. Modini, K. Baumann, E. Edgerton, C. Knote, A. Laskin, B. Wang, and J. L. Fry
                                    Atmos. Chem. Phys., 15, 10669–10685, https://doi.org/10.5194/acp-15-10669-2015, https://doi.org/10.5194/acp-15-10669-2015, 2015
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                                                We report ion chromatographic measurements of gas- and aerosol-phase inorganic species at the SOAS 2013 field study. Our particular focus is on inorganic nitrate aerosol formation via HNO3 uptake onto coarse-mode dust and sea salt particles, which we find to be the dominant source of episodic inorganic nitrate at this site, due to the high acidity of the particles preventing formation of NH4NO3. We calculate a production rate of inorganic nitrate aerosol.
                                            
                                            
                                        L. Lee, P. J. Wooldridge, J. deGouw, S. S. Brown, T. S. Bates, P. K. Quinn, and R. C. Cohen
                                    Atmos. Chem. Phys., 15, 9313–9325, https://doi.org/10.5194/acp-15-9313-2015, https://doi.org/10.5194/acp-15-9313-2015, 2015
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                                                Secondary organic aerosol affects both the environment and human health. We characterized the aerosol composition in Uintah Basin by measuring the concentration of nitrooxy group moiety which is produced through chemical interaction of volatile organic compounds and NOx emitted largely from local human activity. We found nitrooxy compounds to be a persistent, if not dominant, portion of fine aerosol mass. Similar results may be expected from emissions due to traffic in cities.
                                            
                                            
                                        S. H. Budisulistiorini, X. Li, S. T. Bairai, J. Renfro, Y. Liu, Y. J. Liu, K. A. McKinney, S. T. Martin, V. F. McNeill, H. O. T. Pye, A. Nenes, M. E. Neff, E. A. Stone, S. Mueller, C. Knote, S. L. Shaw, Z. Zhang, A. Gold, and J. D. Surratt
                                    Atmos. Chem. Phys., 15, 8871–8888, https://doi.org/10.5194/acp-15-8871-2015, https://doi.org/10.5194/acp-15-8871-2015, 2015
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                                                Isoprene epoxydiols (IEPOX) are major gas-phase products from the atmospheric oxidation of isoprene that yield secondary organic aerosol (SOA) by reactive uptake onto acidic sulfate aerosol. We report a substantial contribution of IEPOX-derived SOA to the total fine aerosol collected during summer. IEPOX-derived SOA measured by online and offline mass spectrometry techniques is correlated with acidic sulfate aerosol, demonstrating the critical role of anthropogenic emissions in its formation.
                                            
                                            
                                        P. R. Veres, J. M. Roberts, R. J. Wild, P. M. Edwards, S. S. Brown, T. S. Bates, P. K. Quinn, J. E. Johnson, R. J. Zamora, and J. de Gouw
                                    Atmos. Chem. Phys., 15, 8101–8114, https://doi.org/10.5194/acp-15-8101-2015, https://doi.org/10.5194/acp-15-8101-2015, 2015
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                                                In this paper laboratory work is documented establishing iodide ion chemical ionization mass spectrometry (I- CIMS) as a sensitive method for the unambiguous detection of peroxynitric acid (HO2NO2; PNA). A dynamic calibration source for HO2NO2, HO2, and HONO was developed and calibrated using a novel total NOy detector (NOy CaRDS). The ambient observations of HO2NO2 using I- CIMS made during the 2013 and 2014 Uintah Basin Wintertime Ozone Study (UBWOS) are presented.
                                            
                                            
                                        J. Kaiser, G. M. Wolfe, K. E. Min, S. S. Brown, C. C. Miller, D. J. Jacob, J. A. deGouw, M. Graus, T. F. Hanisco, J. Holloway, J. Peischl, I. B. Pollack, T. B. Ryerson, C. Warneke, R. A. Washenfelder, and F. N. Keutsch
                                    Atmos. Chem. Phys., 15, 7571–7583, https://doi.org/10.5194/acp-15-7571-2015, https://doi.org/10.5194/acp-15-7571-2015, 2015
                            G. Wohlfahrt, C. Amelynck, C. Ammann, A. Arneth, I. Bamberger, A. H. Goldstein, L. Gu, A. Guenther, A. Hansel, B. Heinesch, T. Holst, L. Hörtnagl, T. Karl, Q. Laffineur, A. Neftel, K. McKinney, J. W. Munger, S. G. Pallardy, G. W. Schade, R. Seco, and N. Schoon
                                    Atmos. Chem. Phys., 15, 7413–7427, https://doi.org/10.5194/acp-15-7413-2015, https://doi.org/10.5194/acp-15-7413-2015, 2015
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                                                Methanol is the second most abundant volatile organic compound in the troposphere and plays a significant role in atmospheric chemistry. While there is consensus about the dominant role of plants as the major source and the reaction with OH as the major sink, global methanol budgets diverge considerably in terms of source/sink estimates. Here we present micrometeorological methanol flux data from eight sites in order to provide a first cross-site synthesis of the terrestrial methanol exchange.
                                            
                                            
                                        N. L. Wagner, C. A. Brock, W. M. Angevine, A. Beyersdorf, P. Campuzano-Jost, D. Day, J. A. de Gouw, G. S. Diskin, T. D. Gordon, M. G. Graus, J. S. Holloway, G. Huey, J. L. Jimenez, D. A. Lack, J. Liao, X. Liu, M. Z. Markovic, A. M. Middlebrook, T. Mikoviny, J. Peischl, A. E. Perring, M. S. Richardson, T. B. Ryerson, J. P. Schwarz, C. Warneke, A. Welti, A. Wisthaler, L. D. Ziemba, and D. M. Murphy
                                    Atmos. Chem. Phys., 15, 7085–7102, https://doi.org/10.5194/acp-15-7085-2015, https://doi.org/10.5194/acp-15-7085-2015, 2015
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                                                This paper investigates the summertime vertical profile of aerosol over the southeastern US using in situ measurements collected from aircraft. We use a vertical mixing model and measurements of CO to predict the vertical profile of aerosol that we would expect from vertical mixing alone and compare with the observed aerosol profile. We found a modest enhancement of aerosol in the cloudy transition layer during shallow cumulus convection and attribute the enhancement to local aerosol formation.
                                            
                                            
                                        D. B. Millet, M. Baasandorj, D. K. Farmer, J. A. Thornton, K. Baumann, P. Brophy, S. Chaliyakunnel, J. A. de Gouw, M. Graus, L. Hu, A. Koss, B. H. Lee, F. D. Lopez-Hilfiker, J. A. Neuman, F. Paulot, J. Peischl, I. B. Pollack, T. B. Ryerson, C. Warneke, B. J. Williams, and J. Xu
                                    Atmos. Chem. Phys., 15, 6283–6304, https://doi.org/10.5194/acp-15-6283-2015, https://doi.org/10.5194/acp-15-6283-2015, 2015
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                                                Formic acid (HCOOH) is an abundant atmospheric acid that affects precipitation chemistry and acidity. HCOOH measurements over the USA are 2-3× larger than can be explained by known sources and sinks, revealing a key gap in current understanding. Observations indicate a large biogenic source plus chemical production across a range of precursors. Model simulations cannot capture the HCOOH diurnal amplitude or nocturnal profile, implying a deposition bias and possibly even larger missing source.
                                            
                                            
                                        A. P. S. Hettiyadura, E. A. Stone, S. Kundu, Z. Baker, E. Geddes, K. Richards, and T. Humphry
                                    Atmos. Meas. Tech., 8, 2347–2358, https://doi.org/10.5194/amt-8-2347-2015, https://doi.org/10.5194/amt-8-2347-2015, 2015
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                                                Organosulfates are SOA products that have proven difficult to quantify. This study addresses the need for authentic quantification standards with a straightforward approach to synthesizing highly pure organosulfate potassium salts. New standards are used to develop a new separation protocol for small, functionalized organosulfates. Upon validation, this method is used to assess sample preparation protocols and to make new measurements of organosulfates in Centreville, Alabama.
                                            
                                            
                                        P. L. Hayes, A. G. Carlton, K. R. Baker, R. Ahmadov, R. A. Washenfelder, S. Alvarez, B. Rappenglück, J. B. Gilman, W. C. Kuster, J. A. de Gouw, P. Zotter, A. S. H. Prévôt, S. Szidat, T. E. Kleindienst, J. H. Offenberg, P. K. Ma, and J. L. Jimenez
                                    Atmos. Chem. Phys., 15, 5773–5801, https://doi.org/10.5194/acp-15-5773-2015, https://doi.org/10.5194/acp-15-5773-2015, 2015
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                                                (1) Four different parameterizations for the formation and chemical evolution of secondary organic aerosol (SOA) are evaluated using a box model representing the Los Angeles region during the CalNex campaign.
(2) The SOA formed only from the oxidation of VOCs is insufficient to explain the observed SOA concentrations.
(3) The amount of SOA mass formed from diesel vehicle emissions is estimated to be 16-27%.
(4) Modeled SOA depends strongly on the P-S/IVOC volatility distribution.
                                            
                                            
                                        A. R. Koss, J. de Gouw, C. Warneke, J. B. Gilman, B. M. Lerner, M. Graus, B. Yuan, P. Edwards, S. S. Brown, R. Wild, J. M. Roberts, T. S. Bates, and P. K. Quinn
                                    Atmos. Chem. Phys., 15, 5727–5741, https://doi.org/10.5194/acp-15-5727-2015, https://doi.org/10.5194/acp-15-5727-2015, 2015
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                                                Extraction of natural gas and oil is associated with a range of possible atmospheric environmental issues. Here we present an analysis of gas-phase hydrocarbon measurements taken in an oil and natural gas extraction area in Utah during a period of high wintertime ozone. We are able to constrain important chemical parameters related to emission sources and rates, hydrocarbon photochemistry, and VOC composition.
                                            
                                            
                                        K. R. Baker, A. G. Carlton, T. E. Kleindienst, J. H. Offenberg, M. R. Beaver, D. R. Gentner, A. H. Goldstein, P. L. Hayes, J. L. Jimenez, J. B. Gilman, J. A. de Gouw, M. C. Woody, H. O. T. Pye, J. T. Kelly, M. Lewandowski, M. Jaoui, P. S. Stevens, W. H. Brune, Y.-H. Lin, C. L. Rubitschun, and J. D. Surratt
                                    Atmos. Chem. Phys., 15, 5243–5258, https://doi.org/10.5194/acp-15-5243-2015, https://doi.org/10.5194/acp-15-5243-2015, 2015
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                                                This work details the evaluation of PM2.5 carbon, VOC precursors, and OH estimated by the CMAQ photochemical transport model using routine and special measurements from the 2010 CalNex field study. Here, CMAQ and most recent emissions inventory (2011 NEI) are used to generate model PM2.5 OC estimates that are examined in novel ways including primary vs. secondary formation, fossil vs. contemporary carbon, OH and HO2 evaluation, and the relationship between key VOC precursors and SOC tracers.
                                            
                                            
                                        R. Thalman, M. T. Baeza-Romero, S. M. Ball, E. Borrás, M. J. S. Daniels, I. C. A. Goodall, S. B. Henry, T. Karl, F. N. Keutsch, S. Kim, J. Mak, P. S. Monks, A. Muñoz, J. Orlando, S. Peppe, A. R. Rickard, M. Ródenas, P. Sánchez, R. Seco, L. Su, G. Tyndall, M. Vázquez, T. Vera, E. Waxman, and R. Volkamer
                                    Atmos. Meas. Tech., 8, 1835–1862, https://doi.org/10.5194/amt-8-1835-2015, https://doi.org/10.5194/amt-8-1835-2015, 2015
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                                                Measurements of α-dicarbonyl compounds, like glyoxal (CHOCHO) and methyl glyoxal (CH3C(O)CHO), are informative about the rate of hydrocarbon oxidation, oxidative capacity, and secondary organic aerosol (SOA) formation in the atmosphere. We have compared nine instruments and seven techniques to measure α-dicarbonyl, using simulation chamber facilities in the US and Europe. We assess our understanding of calibration, precision, accuracy and detection limits, as well as possible sampling biases.
                                            
                                            
                                        B. Yuan, P. R. Veres, C. Warneke, J. M. Roberts, J. B. Gilman, A. Koss, P. M. Edwards, M. Graus, W. C. Kuster, S.-M. Li, R. J. Wild, S. S. Brown, W. P. Dubé, B. M. Lerner, E. J. Williams, J. E. Johnson, P. K. Quinn, T. S. Bates, B. Lefer, P. L. Hayes, J. L. Jimenez, R. J. Weber, R. Zamora, B. Ervens, D. B. Millet, B. Rappenglück, and J. A. de Gouw
                                    Atmos. Chem. Phys., 15, 1975–1993, https://doi.org/10.5194/acp-15-1975-2015, https://doi.org/10.5194/acp-15-1975-2015, 2015
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                                                In this work, secondary formation of formic acid at an urban site and a site in an oil and gas production region is studied. We investigated various gas phase formation pathways of formic acid, including those recently proposed, using a box model. The contributions from aerosol-related processes, fog events and air-snow exchange to formic acid are also quantified.
                                            
                                            
                                        J. Kaiser, G. M. Wolfe, B. Bohn, S. Broch, H. Fuchs, L. N. Ganzeveld, S. Gomm, R. Häseler, A. Hofzumahaus, F. Holland, J. Jäger, X. Li, I. Lohse, K. Lu, A. S. H. Prévôt, F. Rohrer, R. Wegener, R. Wolf, T. F. Mentel, A. Kiendler-Scharr, A. Wahner, and F. N. Keutsch
                                    Atmos. Chem. Phys., 15, 1289–1298, https://doi.org/10.5194/acp-15-1289-2015, https://doi.org/10.5194/acp-15-1289-2015, 2015
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                                                Using measurements acquired from a Zeppelin airship during the PEGASOS 2012 campaign, we show that VOC oxidation alone cannot account for the formaldehyde concentrations observed in the morning over rural Italy. Vertical profiles suggest a ground-level source of HCHO. Incorporating this additional HCHO source into a photochemical model increases calculated O3 production by as much as 12%.
                                            
                                            
                                        C. Warneke, P. Veres, S. M. Murphy, J. Soltis, R. A. Field, M. G. Graus, A. Koss, S.-M. Li, R. Li, B. Yuan, J. M. Roberts, and J. A. de Gouw
                                    Atmos. Meas. Tech., 8, 411–420, https://doi.org/10.5194/amt-8-411-2015, https://doi.org/10.5194/amt-8-411-2015, 2015
                            R. Ahmadov, S. McKeen, M. Trainer, R. Banta, A. Brewer, S. Brown, P. M. Edwards, J. A. de Gouw, G. J. Frost, J. Gilman, D. Helmig, B. Johnson, A. Karion, A. Koss, A. Langford, B. Lerner, J. Olson, S. Oltmans, J. Peischl, G. Pétron, Y. Pichugina, J. M. Roberts, T. Ryerson, R. Schnell, C. Senff, C. Sweeney, C. Thompson, P. R. Veres, C. Warneke, R. Wild, E. J. Williams, B. Yuan, and R. Zamora
                                    Atmos. Chem. Phys., 15, 411–429, https://doi.org/10.5194/acp-15-411-2015, https://doi.org/10.5194/acp-15-411-2015, 2015
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                                                High 2013 wintertime O3 pollution events associated with oil/gas production within the Uinta Basin are studied using a 3D model. It's able quantitatively to reproduce these events using emission estimates of O3 precursors based on ambient measurements (top-down approach), but unable to reproduce them using a recent bottom-up emission inventory for the oil/gas industry. The role of various physical and meteorological processes, chemical species and pathways contributing to high O3 are quantified.
                                            
                                            
                                        T. B. Nguyen, J. D. Crounse, R. H. Schwantes, A. P. Teng, K. H. Bates, X. Zhang, J. M. St. Clair, W. H. Brune, G. S. Tyndall, F. N. Keutsch, J. H. Seinfeld, and P. O. Wennberg
                                    Atmos. Chem. Phys., 14, 13531–13549, https://doi.org/10.5194/acp-14-13531-2014, https://doi.org/10.5194/acp-14-13531-2014, 2014
                            G. Isaacman, N. M. Kreisberg, L. D. Yee, D. R. Worton, A. W. H. Chan, J. A. Moss, S. V. Hering, and A. H. Goldstein
                                    Atmos. Meas. Tech., 7, 4417–4429, https://doi.org/10.5194/amt-7-4417-2014, https://doi.org/10.5194/amt-7-4417-2014, 2014
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                                                We present here a new in situ instrument for ambient measurements of highly polar organic semi-volatile and low-volatility compounds in both the gas and particle phase by gas chromatography. Compounds previously measured only through filter collection and offline analysis can now be measured hourly with, in most cases, less than 20% uncertainty. This instrument provides unprecedented time resolution and the first ever observations of gas-particle partitioning for most of these compounds.
                                            
                                            
                                        N. M. Kreisberg, D. R. Worton, Y. Zhao, G. Isaacman, A. H. Goldstein, and S. V. Hering
                                    Atmos. Meas. Tech., 7, 4431–4444, https://doi.org/10.5194/amt-7-4431-2014, https://doi.org/10.5194/amt-7-4431-2014, 2014
                            L. Lee, P. J. Wooldridge, J. B. Gilman, C. Warneke, J. de Gouw, and R. C. Cohen
                                    Atmos. Chem. Phys., 14, 12441–12454, https://doi.org/10.5194/acp-14-12441-2014, https://doi.org/10.5194/acp-14-12441-2014, 2014
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                                                Alkyl nitrate formation is known to be an important sink of NOx in a wide range of environments. In a study in the Uintah basin in 2012, we find that formation of these compounds represents a more rapid NOx (NO + NO2) sink than does nitric acid formation. This rapid formation is in large part due to the low mean temperature (~0°C) during the study and is consistent with laboratory observations.
                                            
                                            
                                        Y. You, V. P. Kanawade, J. A. de Gouw, A. B. Guenther, S. Madronich, M. R. Sierra-Hernández, M. Lawler, J. N. Smith, S. Takahama, G. Ruggeri, A. Koss, K. Olson, K. Baumann, R. J. Weber, A. Nenes, H. Guo, E. S. Edgerton, L. Porcelli, W. H. Brune, A. H. Goldstein, and S.-H. Lee
                                    Atmos. Chem. Phys., 14, 12181–12194, https://doi.org/10.5194/acp-14-12181-2014, https://doi.org/10.5194/acp-14-12181-2014, 2014
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                                                Amiens play important roles in atmospheric secondary aerosol formation and human health, but the fast response measurements of amines are lacking. Here we show measurements in a southeastern US forest and a moderately polluted midwestern site. Our results show that gas to particle conversion is an important process that controls ambient amine concentrations and that biomass burning is an important source of amines.
                                            
                                            
                                        G. M. Hidy, C. L. Blanchard, K. Baumann, E. Edgerton, S. Tanenbaum, S. Shaw, E. Knipping, I. Tombach, J. Jansen, and J. Walters
                                    Atmos. Chem. Phys., 14, 11893–11914, https://doi.org/10.5194/acp-14-11893-2014, https://doi.org/10.5194/acp-14-11893-2014, 2014
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                                                This paper reviews aerometric measurements from Centreville, Alabama. The measurements show annual trends with air pollution emissions from 1999 to 2013. They provide a context for observations from 1 June to 15 July 2013 supporting the Southern Oxidant and Aerosol Study. An important goal of this experiment was to advance knowledge of aerosols produced in the atmosphere from precursors. The observations were in moist and warm conditions with the lowest gas and particle concentrations recorded.
                                            
                                            
                                        R. Li, C. Warneke, M. Graus, R. Field, F. Geiger, P. R. Veres, J. Soltis, S.-M. Li, S. M. Murphy, C. Sweeney, G. Pétron, J. M. Roberts, and J. de Gouw
                                    Atmos. Meas. Tech., 7, 3597–3610, https://doi.org/10.5194/amt-7-3597-2014, https://doi.org/10.5194/amt-7-3597-2014, 2014
                            C. Warneke, F. Geiger, P. M. Edwards, W. Dube, G. Pétron, J. Kofler, A. Zahn, S. S. Brown, M. Graus, J. B. Gilman, B. M. Lerner, J. Peischl, T. B. Ryerson, J. A. de Gouw, and J. M. Roberts
                                    Atmos. Chem. Phys., 14, 10977–10988, https://doi.org/10.5194/acp-14-10977-2014, https://doi.org/10.5194/acp-14-10977-2014, 2014
                            P. K. Misztal, T. Karl, R. Weber, H. H. Jonsson, A. B. Guenther, and A. H. Goldstein
                                    Atmos. Chem. Phys., 14, 10631–10647, https://doi.org/10.5194/acp-14-10631-2014, https://doi.org/10.5194/acp-14-10631-2014, 2014
                            W. Ait-Helal, A. Borbon, S. Sauvage, J. A. de Gouw, A. Colomb, V. Gros, F. Freutel, M. Crippa, C. Afif, U. Baltensperger, M. Beekmann, J.-F. Doussin, R. Durand-Jolibois, I. Fronval, N. Grand, T. Leonardis, M. Lopez, V. Michoud, K. Miet, S. Perrier, A. S. H. Prévôt, J. Schneider, G. Siour, P. Zapf, and N. Locoge
                                    Atmos. Chem. Phys., 14, 10439–10464, https://doi.org/10.5194/acp-14-10439-2014, https://doi.org/10.5194/acp-14-10439-2014, 2014
                            T. R. Dallmann, T. B. Onasch, T. W. Kirchstetter, D. R. Worton, E. C. Fortner, S. C. Herndon, E. C. Wood, J. P. Franklin, D. R. Worsnop, A. H. Goldstein, and R. A. Harley
                                    Atmos. Chem. Phys., 14, 7585–7599, https://doi.org/10.5194/acp-14-7585-2014, https://doi.org/10.5194/acp-14-7585-2014, 2014
                            S. H. Budisulistiorini, M. R. Canagaratna, P. L. Croteau, K. Baumann, E. S. Edgerton, M. S. Kollman, N. L. Ng, V. Verma, S. L. Shaw, E. M. Knipping, D. R. Worsnop, J. T. Jayne, R.J. Weber, and J. D. Surratt
                                    Atmos. Meas. Tech., 7, 1929–1941, https://doi.org/10.5194/amt-7-1929-2014, https://doi.org/10.5194/amt-7-1929-2014, 2014
                            J. Ortega, A. Turnipseed, A. B. Guenther, T. G. Karl, D. A. Day, D. Gochis, J. A. Huffman, A. J. Prenni, E. J. T. Levin, S. M. Kreidenweis, P. J. DeMott, Y. Tobo, E. G. Patton, A. Hodzic, Y. Y. Cui, P. C. Harley, R. S. Hornbrook, E. C. Apel, R. K. Monson, A. S. D. Eller, J. P. Greenberg, M. C. Barth, P. Campuzano-Jost, B. B. Palm, J. L. Jimenez, A. C. Aiken, M. K. Dubey, C. Geron, J. Offenberg, M. G. Ryan, P. J. Fornwalt, S. C. Pryor, F. N. Keutsch, J. P. DiGangi, A. W. H. Chan, A. H. Goldstein, G. M. Wolfe, S. Kim, L. Kaser, R. Schnitzhofer, A. Hansel, C. A. Cantrell, R. L. Mauldin, and J. N. Smith
                                    Atmos. Chem. Phys., 14, 6345–6367, https://doi.org/10.5194/acp-14-6345-2014, https://doi.org/10.5194/acp-14-6345-2014, 2014
                            C. Knote, A. Hodzic, J. L. Jimenez, R. Volkamer, J. J. Orlando, S. Baidar, J. Brioude, J. Fast, D. R. Gentner, A. H. Goldstein, P. L. Hayes, W. B. Knighton, H. Oetjen, A. Setyan, H. Stark, R. Thalman, G. Tyndall, R. Washenfelder, E. Waxman, and Q. Zhang
                                    Atmos. Chem. Phys., 14, 6213–6239, https://doi.org/10.5194/acp-14-6213-2014, https://doi.org/10.5194/acp-14-6213-2014, 2014
                            J. Kaiser, X. Li, R. Tillmann, I. Acir, F. Holland, F. Rohrer, R. Wegener, and F. N. Keutsch
                                    Atmos. Meas. Tech., 7, 1571–1580, https://doi.org/10.5194/amt-7-1571-2014, https://doi.org/10.5194/amt-7-1571-2014, 2014
                            D. R. Gentner, E. Ormeño, S. Fares, T. B. Ford, R. Weber, J.-H. Park, J. Brioude, W. M. Angevine, J. F. Karlik, and A. H. Goldstein
                                    Atmos. Chem. Phys., 14, 5393–5413, https://doi.org/10.5194/acp-14-5393-2014, https://doi.org/10.5194/acp-14-5393-2014, 2014
                            D. R. Gentner, T. B. Ford, A. Guha, K. Boulanger, J. Brioude, W. M. Angevine, J. A. de Gouw, C. Warneke, J. B. Gilman, T. B. Ryerson, J. Peischl, S. Meinardi, D. R. Blake, E. Atlas, W. A. Lonneman, T. E. Kleindienst, M. R. Beaver, J. M. St. Clair, P. O. Wennberg, T. C. VandenBoer, M. Z. Markovic, J. G. Murphy, R. A. Harley, and A. H. Goldstein
                                    Atmos. Chem. Phys., 14, 4955–4978, https://doi.org/10.5194/acp-14-4955-2014, https://doi.org/10.5194/acp-14-4955-2014, 2014
                            G. M. Wolfe, C. Cantrell, S. Kim, R. L. Mauldin III, T. Karl, P. Harley, A. Turnipseed, W. Zheng, F. Flocke, E. C. Apel, R. S. Hornbrook, S. R. Hall, K. Ullmann, S. B. Henry, J. P. DiGangi, E. S. Boyle, L. Kaser, R. Schnitzhofer, A. Hansel, M. Graus, Y. Nakashima, Y. Kajii, A. Guenther, and F. N. Keutsch
                                    Atmos. Chem. Phys., 14, 4715–4732, https://doi.org/10.5194/acp-14-4715-2014, https://doi.org/10.5194/acp-14-4715-2014, 2014
                            S. E. Pusede, D. R. Gentner, P. J. Wooldridge, E. C. Browne, A. W. Rollins, K.-E. Min, A. R. Russell, J. Thomas, L. Zhang, W. H. Brune, S. B. Henry, J. P. DiGangi, F. N. Keutsch, S. A. Harrold, J. A. Thornton, M. R. Beaver, J. M. St. Clair, P. O. Wennberg, J. Sanders, X. Ren, T. C. VandenBoer, M. Z. Markovic, A. Guha, R. Weber, A. H. Goldstein, and R. C. Cohen
                                    Atmos. Chem. Phys., 14, 3373–3395, https://doi.org/10.5194/acp-14-3373-2014, https://doi.org/10.5194/acp-14-3373-2014, 2014
                            K. C. Wells, D. B. Millet, K. E. Cady-Pereira, M. W. Shephard, D. K. Henze, N. Bousserez, E. C. Apel, J. de Gouw, C. Warneke, and H. B. Singh
                                    Atmos. Chem. Phys., 14, 2555–2570, https://doi.org/10.5194/acp-14-2555-2014, https://doi.org/10.5194/acp-14-2555-2014, 2014
                            J. J. Ensberg, P. L. Hayes, J. L. Jimenez, J. B. Gilman, W. C. Kuster, J. A. de Gouw, J. S. Holloway, T. D. Gordon, S. Jathar, A. L. Robinson, and J. H. Seinfeld
                                    Atmos. Chem. Phys., 14, 2383–2397, https://doi.org/10.5194/acp-14-2383-2014, https://doi.org/10.5194/acp-14-2383-2014, 2014
                            J.-H. Park, S. Fares, R. Weber, and A. H. Goldstein
                                    Atmos. Chem. Phys., 14, 231–244, https://doi.org/10.5194/acp-14-231-2014, https://doi.org/10.5194/acp-14-231-2014, 2014
                            L. Kaser, T. Karl, A. Guenther, M. Graus, R. Schnitzhofer, A. Turnipseed, L. Fischer, P. Harley, M. Madronich, D. Gochis, F. N. Keutsch, and A. Hansel
                                    Atmos. Chem. Phys., 13, 11935–11947, https://doi.org/10.5194/acp-13-11935-2013, https://doi.org/10.5194/acp-13-11935-2013, 2013
                            A. M. Ortega, D. A. Day, M. J. Cubison, W. H. Brune, D. Bon, J. A. de Gouw, and J. L. Jimenez
                                    Atmos. Chem. Phys., 13, 11551–11571, https://doi.org/10.5194/acp-13-11551-2013, https://doi.org/10.5194/acp-13-11551-2013, 2013
                            S. S. Brown, W. P. Dubé, R. Bahreini, A. M. Middlebrook, C. A. Brock, C. Warneke, J. A. de Gouw, R. A. Washenfelder, E. Atlas, J. Peischl, T. B. Ryerson, J. S. Holloway, J. P. Schwarz, R. Spackman, M. Trainer, D. D. Parrish, F. C. Fehshenfeld, and A. R. Ravishankara
                                    Atmos. Chem. Phys., 13, 11317–11337, https://doi.org/10.5194/acp-13-11317-2013, https://doi.org/10.5194/acp-13-11317-2013, 2013
                            N. Unger, K. Harper, Y. Zheng, N. Y. Kiang, I. Aleinov, A. Arneth, G. Schurgers, C. Amelynck, A. Goldstein, A. Guenther, B. Heinesch, C. N. Hewitt, T. Karl, Q. Laffineur, B. Langford, K. A. McKinney, P. Misztal, M. Potosnak, J. Rinne, S. Pressley, N. Schoon, and D. Serça
                                    Atmos. Chem. Phys., 13, 10243–10269, https://doi.org/10.5194/acp-13-10243-2013, https://doi.org/10.5194/acp-13-10243-2013, 2013
                            R. Holzinger, A. H. Goldstein, P. L. Hayes, J. L. Jimenez, and J. Timkovsky
                                    Atmos. Chem. Phys., 13, 10125–10141, https://doi.org/10.5194/acp-13-10125-2013, https://doi.org/10.5194/acp-13-10125-2013, 2013
                            P. M. Edwards, C. J. Young, K. Aikin, J. deGouw, W. P. Dubé, F. Geiger, J. Gilman, D. Helmig, J. S. Holloway, J. Kercher, B. Lerner, R. Martin, R. McLaren, D. D. Parrish, J. Peischl, J. M. Roberts, T. B. Ryerson, J. Thornton, C. Warneke, E. J. Williams, and S. S. Brown
                                    Atmos. Chem. Phys., 13, 8955–8971, https://doi.org/10.5194/acp-13-8955-2013, https://doi.org/10.5194/acp-13-8955-2013, 2013
                            S. Kundu, T. A. Quraishi, G. Yu, C. Suarez, F. N. Keutsch, and E. A. Stone
                                    Atmos. Chem. Phys., 13, 4865–4875, https://doi.org/10.5194/acp-13-4865-2013, https://doi.org/10.5194/acp-13-4865-2013, 2013
                            K. Kristensen, K. L. Enggrob, S. M. King, D. R. Worton, S. M. Platt, R. Mortensen, T. Rosenoern, J. D. Surratt, M. Bilde, A. H. Goldstein, and M. Glasius
                                    Atmos. Chem. Phys., 13, 3763–3776, https://doi.org/10.5194/acp-13-3763-2013, https://doi.org/10.5194/acp-13-3763-2013, 2013
                            J.-H. Park, A. H. Goldstein, J. Timkovsky, S. Fares, R. Weber, J. Karlik, and R. Holzinger
                                    Atmos. Chem. Phys., 13, 1439–1456, https://doi.org/10.5194/acp-13-1439-2013, https://doi.org/10.5194/acp-13-1439-2013, 2013
                            R. J. Yokelson, I. R. Burling, J. B. Gilman, C. Warneke, C. E. Stockwell, J. de Gouw, S. K. Akagi, S. P. Urbanski, P. Veres, J. M. Roberts, W. C. Kuster, J. Reardon, D. W. T. Griffith, T. J. Johnson, S. Hosseini, J. W. Miller, D. R. Cocker III, H. Jung, and D. R. Weise
                                    Atmos. Chem. Phys., 13, 89–116, https://doi.org/10.5194/acp-13-89-2013, https://doi.org/10.5194/acp-13-89-2013, 2013
                            Related subject area
            Subject: Aerosols | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
            
                    
                        
                            
                            
                                     
                                Technical note: Towards a stronger observational support for haze pollution control by interpreting carbonaceous aerosol results derived from different measurement approaches
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Particle flux–gradient relationships in the high Arctic: emission and deposition patterns across three surface types
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Advances in characterization of black carbon particles and their associated coatings using the soot-particle aerosol mass spectrometer in Singapore, a complex city environment
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Iron isotopes suggest significant aerosol dissolution over the Pacific Ocean
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Enrichment of organic nitrogen in fog residuals observed in the Italian Po Valley
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Asian dust transport of proteinaceous matter from the Gobi Desert to northern China
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Machine-learning-assisted chemical characterization and optical properties of atmospheric brown carbon in Nanjing, China
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Technical note: Reconstructing missing surface aerosol elemental carbon data in long-term series with ensemble learning
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Enhanced emission of intermediate-volatility/semi-volatile organic matter in gas and particle phases from ship exhausts with low-sulfur fuels
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Measurement report: Crustal materials play an increasing role in elevating particle pH – insights from 12-year records in a typical inland city of China
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Significant contributions of biomass burning to PM2.5-bound aromatic compounds: insights from field observations and quantum chemical calculations
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Measurement report: In-depth characterization of ship emissions during operations in a Mediterranean port
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Direct measurement of N2O5 heterogeneous uptake coefficients on atmospheric aerosols in southwestern China and evaluation of current parameterizations
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Measurement report: Per- and polyfluoroalkyl substances (PFAS) in particulate matter (PM10) from activated sludge aeration
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                African dust transported to Barbados in the wintertime lacks indicators of chemical aging
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                A 60-year atmospheric nitrate isotope record from a southeastern Greenland ice core with minimal postdepositional alteration
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Measurement report: Characterization of aerosol hygroscopicity over Southeast Asia during the NASA CAMP2Ex campaign
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Long–term Trends in PM2.5 Chemical Composition and Its Impact on Aerosol Properties: Field Observations from 2007 to 2020 in Pearl River Delta, South China
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Atmospheric Organosulfate Formation Regulated by Continental Outflows and Marine Emissions over East Asian Marginal Seas
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Individual particle compositions and aerosol mixing states at different altitudes over the ocean in East Asia
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Molecular characterization of organic aerosols in urban and forested areas of Paris using high-resolution mass spectrometry
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Measurement report: Wintertime aerosol characterization at an urban traffic site in Helsinki, Finland
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Source apportionment and ecotoxicity of PM2.5 pollution events in a major Southern Hemisphere megacity: influence of a biofuel-impacted fleet and biomass burning
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                The impacts of pollution sources and temperature on the light absorption of HULIS were revealed by UHPLC-HRMS/MS at the molecular structure level
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Effects of Anthropogenic Pollutants on Biogenic Secondary Organic Aerosol Formation in the Atmosphere of Mt. Hua, China
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Marine organic aerosol at Mace Head: effects from phytoplankton and source region variability
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Elemental composition, iron mineralogy and solubility of anthropogenic and natural mineral dust aerosols in Namibia: a case study analysis from the AEROCLO-sA campaign
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Fossil-Dominated SOA Formation in Coastal China: Size-Divergent Pathways of Aqueous Fenton Reactions versus Gas-phase VOC Autoxidation
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Measurement report: Sources and meteorology influencing highly time-resolved PM2.5 trace elements at three urban sites in the extremely polluted Indo-Gangetic Plain in India
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Formation of highly absorptive secondary brown carbon through nighttime multiphase chemistry of biomass burning emissions
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Hydroxymethanesulfonate (HMS) Formation under Urban and Marine Atmosphere: role of aerosol ionic strength
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                The sources and diurnal variations of submicron aerosols in a coastal-rural environment near Houston, US
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Measurement report: Vertically resolved atmospheric properties observed over the Southern Great Plains with the ArcticShark uncrewed aerial system
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Unraveling Arctic submicron organic aerosol sources: a year-long study by H-NMR and AMS in Ny-Ålesund, Svalbard
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Non-biogenic sources are an important but overlooked contributor to aerosol isoprene-derived organosulfates during winter in northern China
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Unveiling single-particle composition, size, shape, and mixing state of freshly emitted Icelandic dust via electron microscopy analysis
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                The Critical Role of Volatile Organic Compounds Emission in Nitrate Formation in Lhasa, Tibetan Plateau: Insights from Oxygen Isotope Anomaly Measurements
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                The critical role of aqueous-phase processes in aromatic-derived nitrogen-containing organic aerosol formation in cities with different energy consumption patterns
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Characterization of atmospheric water-soluble brown carbon in the Athabasca oil sands region, Canada
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Sensitivity of aerosol and cloud properties to coupling strength of marine boundary layer clouds over the northwest Atlantic
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Measurement Report: Molecular composition, sources, and evolution of atmospheric organic aerosols in a basin city in China
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Burning conditions and transportation pathways determine biomass-burning aerosol properties in the Ascension Island marine boundary layer
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Observations of high-time-resolution and size-resolved aerosol chemical composition and microphysics in the central Arctic: implications for climate-relevant particle properties
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Measurement report: Brown carbon aerosol in rural Germany – sources, chemistry, and diurnal variations
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Climatology of aerosol pH and its controlling factors at the Melpitz continental background site in central Europe
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Atmospheric chemistry in East Asia determines the iron solubility of aerosol particles supplied to the North Pacific Ocean
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Measurement Report: Polycyclic aromatic hydrocarbons (PAHs) and their alkylated (RPAHs), nitrated (NPAHs) and oxygenated (OPAHs) derivatives in the global marine atmosphere: occurrence, spatial variations, and source apportionment
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Multiple eco-regions contribute to the seasonal cycle of Antarctic aerosol size distributions
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Seasonal investigation of ultrafine-particle organic composition in an eastern Amazonian rainforest
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Characterizing lead-rich particles in Beijing's atmosphere following coal-to-gas conversion: Insights from single particle aerosol mass spectrometry
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
            
        
        Yuan Cheng, Ying-jie Zhong, Zhi-qing Zhang, Xu-bing Cao, and Jiu-meng Liu
                                    Atmos. Chem. Phys., 25, 8493–8505, https://doi.org/10.5194/acp-25-8493-2025, https://doi.org/10.5194/acp-25-8493-2025, 2025
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                                                As an emerging hotspot of atmospheric sciences, northeastern China is distinct due to the frigid winter and the strong emissions from agricultural fires. Based on field campaigns conducted in Harbin, we successively identified the analytical method that could lead to proper results of organic and elemental carbon. Our results are believed to be a support for future efforts in the exploration of PM2.5 sources in northeastern China, which are essential for further improving the regional air quality.
                                            
                                            
                                        Theresa Mathes, Heather Guy, John Prytherch, Julia Kojoj, Ian Brooks, Sonja Murto, Paul Zieger, Birgit Wehner, Michael Tjernström, and Andreas Held
                                    Atmos. Chem. Phys., 25, 8455–8474, https://doi.org/10.5194/acp-25-8455-2025, https://doi.org/10.5194/acp-25-8455-2025, 2025
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                                                The Arctic is warming faster than the global average and an investigation of aerosol–cloud–sea ice interactions is crucial for studying its climate system. During the ARTofMELT Expedition 2023, particle and sensible heat fluxes were measured over different surfaces. Wide lead surfaces acted as particle sources, with the strongest sensible heat fluxes, while closed ice surfaces acted as particle sinks. In this study, methods to measure these interactions are improved, enhancing our understanding of Arctic climate processes.
                                            
                                            
                                        Mutian Ma, Laura-Hélèna Rivellini, Yichen Zong, Markus Kraft, Liya E. Yu, and Alex King Yin Lee
                                    Atmos. Chem. Phys., 25, 8185–8211, https://doi.org/10.5194/acp-25-8185-2025, https://doi.org/10.5194/acp-25-8185-2025, 2025
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                                                This work advances our understanding of the emission and atmospheric evolution of black carbon (BC) particles in Singapore, a complex urban environment impacted by multiple local and regional combustion sources, based on the improved source apportionment analysis of real-time aerosol mass spectrometry measurement.
                                            
                                            
                                        Capucine Camin, François Lacan, Catherine Pradoux, Marie Labatut, Anne Johansen, and James W. Murray
                                    Atmos. Chem. Phys., 25, 8213–8228, https://doi.org/10.5194/acp-25-8213-2025, https://doi.org/10.5194/acp-25-8213-2025, 2025
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                                                This paper presents the chemical and iron isotopic composition of aerosols (> 1 µm) over the equatorial and tropical Pacific Ocean in previously undocumented areas. Analysis of our data suggests that a significant proportion of aerosol iron (∼ 13 %) is not only dissolved but also removed during atmospheric transport. Such removal had not previously been evidenced to our knowledge. This highlights the unique and strong constraints brought by iron isotopes on atmospheric process studies.
                                            
                                            
                                        Fredrik Mattsson, Almuth Neuberger, Liine Heikkinen, Yvette Gramlich, Marco Paglione, Matteo Rinaldi, Stefano Decesari, Paul Zieger, Ilona Riipinen, and Claudia Mohr
                                    Atmos. Chem. Phys., 25, 7973–7989, https://doi.org/10.5194/acp-25-7973-2025, https://doi.org/10.5194/acp-25-7973-2025, 2025
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                                                This study investigated aerosol–cloud interactions, focusing on organic nitrogen (ON) formation in the aqueous phase. Measurements were conducted in wintertime in the Po Valley, Italy, using aerosol mass spectrometry. The fog was enriched in more hygroscopic inorganic compounds and ON, containing, e.g., imidazoles. The formation of imidazole by aerosol–fog interactions could be confirmed for the first time in atmospheric observations. Findings highlight the role of fog in nitrogen aerosol formation.
                                            
                                            
                                        Ren-Guo Zhu, Hua-Yun Xiao, Meiju Yin, Hao Xiao, Zhongkui Zhou, Yuanyuan Pan, Guo Wei, and Cheng Liu
                                    Atmos. Chem. Phys., 25, 7699–7718, https://doi.org/10.5194/acp-25-7699-2025, https://doi.org/10.5194/acp-25-7699-2025, 2025
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                                                The concentrations and δ15N isotopic values of CAAs (combined amino acids) in surface soil and plants from the Gobi Desert, as well as in PM2.5 samples from four cities in Northern China, were measured. CAAs transported by Gobi dust were rich in alanine, glycine and glutamic acid. Glycine and leucine in Gobi Desert sources exhibited δ15N depletion by more than 6 ‰ compared to their values in urban PM2.5. Substantial protein-N deposition can be transported by the Gobi Desert to northern China over brief periods.
                                            
                                            
                                        Yu Huang, Xingru Li, Dan Dan Huang, Ruoyuan Lei, Binhuang Zhou, Yunjiang Zhang, and Xinlei Ge
                                    Atmos. Chem. Phys., 25, 7619–7645, https://doi.org/10.5194/acp-25-7619-2025, https://doi.org/10.5194/acp-25-7619-2025, 2025
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                                                This work comprises a comprehensive investigation into the chemical and optical properties of brown carbon (BrC) in PM2.5 samples collected in Nanjing, China. In particular, we used a machine learning approach to identify a list of key BrC species, which can be a good reference for future studies. Our findings extend understanding of BrC properties and are valuable to the assessment of BrC's impact on air quality and radiative forcing.
                                            
                                            
                                        Qingxiao Meng, Yunjiang Zhang, Sheng Zhong, Jie Fang, Lili Tang, Yongcai Rao, Minfeng Zhou, Jian Qiu, Xiaofeng Xu, Jean-Eudes Petit, Olivier Favez, and Xinlei Ge
                                    Atmos. Chem. Phys., 25, 7485–7498, https://doi.org/10.5194/acp-25-7485-2025, https://doi.org/10.5194/acp-25-7485-2025, 2025
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                                                We developed a machine-learning-based method to reconstruct missing elemental carbon (EC) data in four Chinese cities from 2013 to 2023. Using machine learning, we filled data gaps and introduced a new approach to analyze EC trends. Our findings reveal a significant decline in EC due to stricter pollution controls, though this slowed after 2020. This study provides a versatile framework for addressing data gaps and supports strategies to reduce urban air pollution and its climate impacts.
                                            
                                            
                                        Binyu Xiao, Fan Zhang, Zeyu Liu, Yan Zhang, Rui Li, Can Wu, Xinyi Wan, Yi Wang, Yubao Chen, Yong Han, Min Cui, Libo Zhang, Yingjun Chen, and Gehui Wang
                                    Atmos. Chem. Phys., 25, 7053–7069, https://doi.org/10.5194/acp-25-7053-2025, https://doi.org/10.5194/acp-25-7053-2025, 2025
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                                                Intermediate-volatility/semi-volatile organic compounds in gas and particle phases from ship exhausts are enhanced due to the switch of fuels from low sulfur to ultra-low sulfur. The findings indicate that optimization is necessary for the forthcoming global implementation of an ultra-low-sulfur oil policy. Besides, we find that organic diagnostic markers of hopanes in conjunction with the ratio of octadecanoic to tetradecanoic could be considered potential tracers for heavy fuel oil exhausts.
                                            
                                            
                                        Hongyu Zhang, Shenbo Wang, Zhangsen Dong, Xiao Li, and Ruiqin Zhang
                                    Atmos. Chem. Phys., 25, 6943–6955, https://doi.org/10.5194/acp-25-6943-2025, https://doi.org/10.5194/acp-25-6943-2025, 2025
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                                                Analyzing 12-year Zhengzhou data revealed post-2019 crustal material rebound caused by soil dust resuspension, elevating particle pH. Similar coarse particle increases are observed across cities of the North China Plain. Long-term particle acidity evolution in this region requires an integrated assessment of interactions among acidic precursors, ammonia, and crustal components.
                                            
                                            
                                        Yanqin Ren, Zhenhai Wu, Fang Bi, Hong Li, Haijie Zhang, Junling Li, Rui Gao, Fangyun Long, Zhengyang Liu, Yuanyuan Ji, and Gehui Wang
                                    Atmos. Chem. Phys., 25, 6975–6990, https://doi.org/10.5194/acp-25-6975-2025, https://doi.org/10.5194/acp-25-6975-2025, 2025
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                                                The daily concentrations of Polycyclic aromatic hydrocarbons (PAHs), oxygenated PAHs (OPAHs), and nitrated phenols (NPs) in PM2.5 were all increased during the heating season. Biomass burning was identified to be the primary source of these aromatic compounds, particularly for PAHs. Phenol and nitrobenzene are two main primary precursors for 4NP, with phenol showing lower reaction barriers. P-Cresol was identified as the primary precursor for the formation of 4-methyl-5-nitrocatechol.
                                            
                                            
                                        Lise Le Berre, Brice Temime-Roussel, Grazia Maria Lanzafame, Barbara D'Anna, Nicolas Marchand, Stéphane Sauvage, Marvin Dufresne, Liselotte Tinel, Thierry Leonardis, Joel Ferreira de Brito, Alexandre Armengaud, Grégory Gille, Ludovic Lanzi, Romain Bourjot, and Henri Wortham
                                    Atmos. Chem. Phys., 25, 6575–6605, https://doi.org/10.5194/acp-25-6575-2025, https://doi.org/10.5194/acp-25-6575-2025, 2025
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                                                A summer campaign in a Mediterranean port examined pollution caused by ships. Two stations in the port measured pollution levels and captured over 350 ship plumes to study their chemical composition. Results showed that pollution levels, such as ultra-fine particles, were higher in the port than in the city and offer strong support to improve emission inventories. These findings may also serve as reference to assess the benefits of a sulfur Emission Control Area in the Mediterranean in 2025.
                                            
                                            
                                        Jiayin Li, Tianyu Zhai, Xiaorui Chen, Haichao Wang, Shuyang Xie, Shiyi Chen, Chunmeng Li, Yuanjun Gong, Huabin Dong, and Keding Lu
                                    Atmos. Chem. Phys., 25, 6395–6406, https://doi.org/10.5194/acp-25-6395-2025, https://doi.org/10.5194/acp-25-6395-2025, 2025
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                                                We directly measured the dinitrogen pentoxide (N2O5) uptake coefficient using an aerosol flow tube, which critically impacts the NOx fate and particulate nitrate formation in a typical highland city, Kunming, in China. We found that the performance of current γ (N2O5) parameterizations showed deviations with the varying aerosol liquid water content (ALWC). Such differences would lead to biased estimation of particulate nitrate production potential. We give suggestions for future research directions.
                                            
                                            
                                        Jishnu Pandamkulangara Kizhakkethil, Zongbo Shi, Anna Bogush, and Ivan Kourtchev
                                    Atmos. Chem. Phys., 25, 5947–5958, https://doi.org/10.5194/acp-25-5947-2025, https://doi.org/10.5194/acp-25-5947-2025, 2025
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                                                Pollution with per- and polyfluoroalkyl substances (PFAS) has received attention due to their environmental persistence and bioaccumulation, but their sources remain poorly understood. PM10 (particulate matter) collected above a scaled-down activated sludge tank treating domestic sewage in the UK was analysed for a range of short-, medium-, and long-chain PFAS. Eight PFAS were detected in the PM10. Our results suggest that wastewater treatment processes, i.e. activated sludge aeration, could aerosolise PFAS into airborne PM.
                                            
                                            
                                        Haley M. Royer, Michael T. Sheridan, Hope E. Elliott, Edmund Blades, Nurun Nahar Lata, Zezhen Cheng, Swarup China, Zihua Zhu, Andrew P. Ault, and Cassandra J. Gaston
                                    Atmos. Chem. Phys., 25, 5743–5759, https://doi.org/10.5194/acp-25-5743-2025, https://doi.org/10.5194/acp-25-5743-2025, 2025
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                                                Saharan dust transported across the Atlantic to the Caribbean, South America, and North America is hypothesized to undergo chemical processing by acids that enhances cloud droplet formation and nutrient availability. In this study, chemical analysis performed on African dust deposited over Barbados shows that acid tracers are found mostly on sea salt and smoke particles, rather than dust, indicating that dust particles undergo minimal chemical processing.
                                            
                                            
                                        Zhao Wei, Shohei Hattori, Asuka Tsuruta, Zhuang Jiang, Sakiko Ishino, Koji Fujita, Sumito Matoba, Lei Geng, Alexis Lamothe, Ryu Uemura, Naohiro Yoshida, Joel Savarino, and Yoshinori Iizuka
                                    Atmos. Chem. Phys., 25, 5727–5742, https://doi.org/10.5194/acp-25-5727-2025, https://doi.org/10.5194/acp-25-5727-2025, 2025
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                                                Nitrate isotope records in ice cores reveal changes in NOₓ emissions and atmospheric oxidation chemistry driven by human activity. However, UV-driven postdepositional processes can alter nitrate in snow, making snow accumulation rates critical for preserving these records. This study examines nitrate isotopes in a southeastern Greenland ice core, where high snow accumulation minimizes these effects, providing a reliable archive of atmospheric nitrogen cycling.
                                            
                                            
                                        Genevieve Rose Lorenzo, Luke D. Ziemba, Avelino F. Arellano, Mary C. Barth, Ewan C. Crosbie, Joshua P. DiGangi, Glenn S. Diskin, Richard Ferrare, Miguel Ricardo A. Hilario, Michael A. Shook, Simone Tilmes, Jian Wang, Qian Xiao, Jun Zhang, and Armin Sorooshian
                                    Atmos. Chem. Phys., 25, 5469–5495, https://doi.org/10.5194/acp-25-5469-2025, https://doi.org/10.5194/acp-25-5469-2025, 2025
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                                                Novel aerosol hygroscopicity analyses of CAMP2Ex (Cloud, Aerosol, and Monsoon Processes Philippines Experiment) field campaign data show low aerosol hygroscopicity values in Southeast Asia. Organic carbon from smoke decreases hygroscopicity to levels more like those in continental than in polluted marine regions. Hygroscopicity changes at cloud level demonstrate how surface particles impact clouds in the region, affecting model representation of aerosol and cloud interactions in similar polluted marine regions with high organic carbon emissions.
                                            
                                            
                                        Yunfeng He, Xiang Ding, Quanfu He, Yuqing Zhang, Duohong Chen, Tao Zhang, Kong Yang, Junqi Wang, Qian Cheng, Hao Jiang, Zirui Wang, Ping Liu, Xinming Wang, and Michael Boy
                                        EGUsphere, https://doi.org/10.5194/egusphere-2025-2204, https://doi.org/10.5194/egusphere-2025-2204, 2025
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                                                The long-term field measurements in the Pearl River Delta revealed a significant decline in PM2.5 main components. As air quality improved, secondary species became more dominant. In addition, the proportion of nitrate had doubled. The changes in chemical composition led to the reductions in aerosol acidity, liquid water content and light extinction coefficient. Our results help to improve understanding of the secondary species formation under decreasing anthropogenic emissions.
                                            
                                            
                                        Shubin Li, Yujue Wang, Yiwen Zhang, Yizhe Yi, Yuchen Wang, Yuqi Guo, Chao Yu, Yue Jiang, Jinhui Shi, Chao Zhang, Jialei Zhu, Wei Hu, Jianzhen Yu, Xiaohong Yao, Huiwang Gao, and Min Hu
                                        EGUsphere, https://doi.org/10.5194/egusphere-2025-2154, https://doi.org/10.5194/egusphere-2025-2154, 2025
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                                                Organosulfates (OSs) are an unrecognized and potentially important component in marine organic aerosols. In this study, we quantified and characterized the OSs over East Asian marginal seas. The chemical nature and spatiotemporal distribution of OSs were modified by the joint influence of marine emissions and transported terrestrial pollutants. The results highlight the vital roles of OSs in shaping organic aerosol formation and sulfur cycle during summer in marine boundary layer.
                                            
                                            
                                        Kouji Adachi, Atsushi Yoshida, Tatsuhiro Mori, Nobuhiro Moteki, Sho Ohata, Kazuyuki Kita, Yoshimi Kawai, and Makoto Koike
                                        EGUsphere, https://doi.org/10.5194/egusphere-2025-2230, https://doi.org/10.5194/egusphere-2025-2230, 2025
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                                                This study measured the compositions and mixing states of individual aerosol particles collected at different altitudes over the western North Pacific by simultaneous sampling from an aircraft and a research vessel. The results showed that they were strongly influenced by Siberian Forest biomass burning and mixed with sea spray, and identified various aerosol compositions at different altitudes, sizes, and aerosol sources, highlighting a wide range of individual particle compositions.
                                            
                                            
                                        Diana L. Pereira, Chiara Giorio, Aline Gratien, Alexander Zherebker, Gael Noyalet, Servanne Chevaillier, Stéphanie Alage, Elie Almarj, Antonin Bergé, Thomas Bertin, Mathieu Cazaunau, Patrice Coll, Ludovico Di Antonio, Sergio Harb, Johannes Heuser, Cécile Gaimoz, Oscar Guillemant, Brigitte Language, Olivier Lauret, Camilo Macias, Franck Maisonneuve, Bénédicte Picquet-Varrault, Raquel Torres, Sylvain Triquet, Pascal Zapf, Lelia Hawkins, Drew Pronovost, Sydney Riley, Pierre-Marie Flaud, Emilie Perraudin, Pauline Pouyes, Eric Villenave, Alexandre Albinet, Olivier Favez, Robin Aujay-Plouzeau, Vincent Michoud, Christopher Cantrell, Manuela Cirtog, Claudia Di Biagio, Jean-François Doussin, and Paola Formenti
                                    Atmos. Chem. Phys., 25, 4885–4905, https://doi.org/10.5194/acp-25-4885-2025, https://doi.org/10.5194/acp-25-4885-2025, 2025
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                                                In order to study aerosols in environments influenced by anthropogenic and biogenic emissions, we performed analyses of samples collected during the ACROSS (Atmospheric Chemistry Of the Suburban Forest) campaign in summer 2022 in the greater Paris area. After analysis of the chemical composition by means of total carbon determination and high-resolution mass spectrometry, this work highlights the influence of anthropogenic inputs on the chemical composition of both urban and forested areas.
                                            
                                            
                                        Kimmo Teinilä, Sanna Saarikoski, Henna Lintusaari, Teemu Lepistö, Petteri Marjanen, Minna Aurela, Heidi Hellén, Toni Tykkä, Markus Lampimäki, Janne Lampilahti, Luis Barreira, Timo Mäkelä, Leena Kangas, Juha Hatakka, Sami Harni, Joel Kuula, Jarkko V. Niemi, Harri Portin, Jaakko Yli-Ojanperä, Ville Niemelä, Milja Jäppi, Katrianne Lehtipalo, Joonas Vanhanen, Liisa Pirjola, Hanna E. Manninen, Tuukka Petäjä, Topi Rönkkö, and Hilkka Timonen
                                    Atmos. Chem. Phys., 25, 4907–4928, https://doi.org/10.5194/acp-25-4907-2025, https://doi.org/10.5194/acp-25-4907-2025, 2025
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                                                Physical and chemical properties of particulate matter and concentrations of trace gases were measured in a street canyon in Helsinki, Finland, and an urban background site in January–February 2022 to investigate the effect of wintertime conditions on pollutants. State-of-the-art instruments and a mobile laboratory were used, and the measurement data were analysed further with modelling tools like positive matrix factorization and the Pollution Detection Algorithm.
                                            
                                            
                                        Guilherme Martins Pereira, Leonardo Yoshiaki Kamigauti, Rubens Fabio Pereira, Djacinto Monteiro dos Santos, Thayná da Silva Santos, José Vinicius Martins, Célia Alves, Cátia Gonçalves, Ismael Casotti Rienda, Nora Kováts, Thiago Nogueira, Luciana Rizzo, Paulo Artaxo, Regina Maura de Miranda, Marcia Akemi Yamasoe, Edmilson Dias de Freitas, Pérola de Castro Vasconcellos, and Maria de Fatima Andrade
                                    Atmos. Chem. Phys., 25, 4587–4616, https://doi.org/10.5194/acp-25-4587-2025, https://doi.org/10.5194/acp-25-4587-2025, 2025
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                                                The chemical composition of fine particulate matter was studied in the megacity of São Paulo (Brazil) during a polluted period. Vehicular-related sources remain relevant; however, a high contribution of biomass burning was observed and correlated with sample ecotoxicity. Emerging biomass burning sources, such as forest fires and sugarcane-bagasse-based power plants, highlight the need for additional control measures alongside stricter rules concerning vehicular emissions.
                                            
                                            
                                        Tao Qiu, Yanting Qiu, Yongyi Yuan, Rui Su, Xiangxinyue Meng, Jialiang Ma, Xiaofan Wang, Yu Gu, Zhijun Wu, Yang Ning, Xiuyi Hua, Dapeng Liang, and Deming Dong
                                        EGUsphere, https://doi.org/10.5194/egusphere-2025-1808, https://doi.org/10.5194/egusphere-2025-1808, 2025
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                                                Our research reveals that some species from biomass burning and coal combustion dominate the light absorption of organic aerosols during winter. Cold weather helps these species accumulate in aerosols by slowing their degradation and altering atmospheric chemical processes. This means colder regions might experience stronger and more persistent climate impacts. Our findings highlight the importance of local temperatures and pollution sources when tackling climate challenges.
                                            
                                            
                                        Can Wu, Yubao Chen, Yuwei Sun, Huijun Zhang, Si Zhang, Cong Cao, Jianjun Li, and Gehui Wang
                                        EGUsphere, https://doi.org/10.5194/egusphere-2025-1668, https://doi.org/10.5194/egusphere-2025-1668, 2025
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                                                Biogenic secondary organic aerosol (BSOA), as an important atmospheric component, is prevalent within the boundary layer and can influence air quality and human health. Our observations demonstrate that anthropogenic NOx and the enhanced aerosol water driven by sulfate inhibit BSOA formation in lifting air masses, leading to a moderate reduction in the SOA burden in the upper boundary layer.
                                            
                                            
                                        Emmanuel Chevassus, Kirsten N. Fossum, Darius Ceburnis, Lu Lei, Chunshui Lin, Wei Xu, Colin O'Dowd, and Jurgita Ovadnevaite
                                    Atmos. Chem. Phys., 25, 4107–4129, https://doi.org/10.5194/acp-25-4107-2025, https://doi.org/10.5194/acp-25-4107-2025, 2025
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                                                This study presents the first source apportionment of organic aerosol at Mace Head via high-resolution mass spectrometry. Introducing transfer entropy as a novel method reveals that aged organic aerosol originates from both open-ocean ozonolysis and local peat-burning oxidation. Methanesulfonic acid and organic sea spray both mirror phytoplankton activity, with the former closely tied to coccolithophore blooms and the latter linked to diatoms, chlorophytes, and cyanobacteria.
                                            
                                            
                                        Paola Formenti, Chiara Giorio, Karine Desboeufs, Alexander Zherebker, Marco Gaetani, Clarissa Baldo, Gautier Landrot, Simona Montebello, Servanne Chevaillier, Sylvain Triquet, Guillaume Siour, Claudia Di Biagio, Francesco Battaglia, Jean-François Doussin, Anais Feron, Andreas Namwoonde, and Stuart John Piketh
                                        EGUsphere, https://doi.org/10.5194/egusphere-2025-446, https://doi.org/10.5194/egusphere-2025-446, 2025
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                                                The elemental composition and solubility of several metals, including iron, at a coastal site in Namibia in August–September 2017, indicate that natural and anthropogenic dust had different solubility depending on mineralogy but mostly to the processing by fluoride ions from marine emissions, pointing out to the complexity of atmospheric/oceanic interactions in this region of the world influenced by the Benguela current and significant aerosol load.
                                            
                                            
                                        Jia-Yuan Wang, Meng-Xue Tang, Shan Lu, Ke-Jin Tang, Xing Peng, Ling-Yan He, and Xiao-Feng Huang
                                        EGUsphere, https://doi.org/10.5194/egusphere-2025-1034, https://doi.org/10.5194/egusphere-2025-1034, 2025
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                                                Our study explores how secondary organic aerosols (SOA), a major component of air pollution, form in different particle sizes in a coastal city in China. We found that SOA in fine particles is mainly produced through aqueous chemical reactions, especially those involving iron. In contrast, coarse particles form SOA through reactions with ozone and gases from both fossil fuels and natural sources. These findings highlight the need for size-specific air pollution models.
                                            
                                            
                                        Ashutosh K. Shukla, Sachchida N. Tripathi, Shamitaksha Talukdar, Vishnu Murari, Sreenivas Gaddamidi, Manousos-Ioannis Manousakas, Vipul Lalchandani, Kuldeep Dixit, Vinayak M. Ruge, Peeyush Khare, Mayank Kumar, Vikram Singh, Neeraj Rastogi, Suresh Tiwari, Atul K. Srivastava, Dilip Ganguly, Kaspar Rudolf Daellenbach, and André S. H. Prévôt
                                    Atmos. Chem. Phys., 25, 3765–3784, https://doi.org/10.5194/acp-25-3765-2025, https://doi.org/10.5194/acp-25-3765-2025, 2025
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                                                Our study delves into the elemental composition of aerosols at three sites across the Indo-Gangetic Plain (IGP), revealing distinct patterns during pollution episodes. We found significant increases in chlorine (Cl)-rich and solid fuel combustion (SFC) sources, indicating dynamic emission sources, agricultural burning impacts, and meteorological influences. Surges in Cl-rich particles during cold periods highlight their role in particle growth under high-relative-humidity conditions.
                                            
                                            
                                        Ye Kuang, Biao Luo, Shan Huang, Junwen Liu, Weiwei Hu, Yuwen Peng, Duohong Chen, Dingli Yue, Wanyun Xu, Bin Yuan, and Min Shao
                                    Atmos. Chem. Phys., 25, 3737–3752, https://doi.org/10.5194/acp-25-3737-2025, https://doi.org/10.5194/acp-25-3737-2025, 2025
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                                                This research reveals the potential importance of nighttime NO3 radical chemistry and aerosol water in the rapid formation of secondary brown carbon from diluted biomass burning emissions. The findings enhance our understanding of nighttime biomass burning evolution and its implications for climate and regional air quality, especially regarding interactions with background aerosol water and water-rich fogs and clouds.
                                            
                                            
                                        Rongshuang Xu, Yu-Chi Lin, Siyu Bian, Feng Xie, and Yan-Lin Zhang
                                        EGUsphere, https://doi.org/10.5194/egusphere-2025-683, https://doi.org/10.5194/egusphere-2025-683, 2025
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                                                This work reported the hydroxymethanesulfonate (HMS) level in a continental city and, for the first time, in marine atmosphere. The enhancement by aerosol ionic strength (IS) on HMS formation was quantified which first rise with increasing IS, peaking at 4 mol kg–1 before declining. Given the IS range of marine (2–6) and urban aerosol (6–20 mol kg–1) and the clearly negative correlation between humidity and IS, the moderate IS level under humid condition may notably boost ambient HMS formation.
                                            
                                            
                                        Jing Li, Jiaoshi Zhang, Xianda Gong, Steven Spielman, Chongai Kuang, Ashish Singh, Maria A. Zawadowicz, Lu Xu, and Jian Wang
                                        EGUsphere, https://doi.org/10.5194/egusphere-2025-726, https://doi.org/10.5194/egusphere-2025-726, 2025
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                                                Using measurements at a rural coastal site, we quantified aerosols in representative air masses and identified major source of organics in Houston area. Our results show cooking aerosol is likely overestimated by earlier studies. Additionally, diurnal variation of highly oxidized organics is mostly driven by air mass changes instead of photochemistry. This study highlights the impacts of emissions, atmospheric chemistry, and meteorology on aerosol properties in the coastal-rural environment.
                                            
                                            
                                        Fan Mei, Qi Zhang, Damao Zhang, Jerome D. Fast, Gourihar Kulkarni, Mikhail S. Pekour, Christopher R. Niedek, Susanne Glienke, Israel Silber, Beat Schmid, Jason M. Tomlinson, Hardeep S. Mehta, Xena Mansoura, Zezhen Cheng, Gregory W. Vandergrift, Nurun Nahar Lata, Swarup China, and Zihua Zhu
                                    Atmos. Chem. Phys., 25, 3425–3444, https://doi.org/10.5194/acp-25-3425-2025, https://doi.org/10.5194/acp-25-3425-2025, 2025
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                                                This study highlights the unique capability of the ArcticShark, an uncrewed aerial system, in measuring vertically resolved atmospheric properties. Data from 32 research flights in 2023 reveal seasonal patterns and correlations with conventional measurements. The consistency and complementarity of in situ and remote sensing methods are highlighted. The study demonstrates the ArcticShark’s versatility in bridging data gaps and improving the understanding of vertical atmospheric structures.
                                            
                                            
                                        Marco Paglione, Yufang Hao, Stefano Decesari, Mara Russo, Karam Mansour, Mauro Mazzola, Diego Fellin, Andrea Mazzanti, Emilio Tagliavini, Manousos Ioannis Manousakas, Evangelia Diapouli, Elena Barbaro, Matteo Feltracco, Kaspar Rudolf Daellenbach, and Matteo Rinaldi
                                        EGUsphere, https://doi.org/10.5194/egusphere-2025-760, https://doi.org/10.5194/egusphere-2025-760, 2025
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                                                A year-long set of PM1 samples from Ny-Ålesund, Svalbard, was analyzed by H-NMR and HR-TOF-AMS for the chemical characterization of the organic fraction. Positive Matrix Factorization allowed to identify five organic aerosol sources with specific seasonality. Winter-spring aerosol is dominated by Eurasian pollution, while summer is characterized by biogenic aerosols from marine sources; occasional summertime high OA loadings are associated with wildfire aerosols.
                                            
                                            
                                        Ting Yang, Yu Xu, Yu-Chen Wang, Yi-Jia Ma, Hong-Wei Xiao, Hao Xiao, and Hua-Yun Xiao
                                    Atmos. Chem. Phys., 25, 2967–2978, https://doi.org/10.5194/acp-25-2967-2025, https://doi.org/10.5194/acp-25-2967-2025, 2025
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                                                Previous measurement–model comparisons of atmospheric isoprene levels showed a significant unidentified source of isoprene in some northern Chinese cities during winter. Here, the first combination of large-scale observations and field combustion experiments provides novel insights into biomass burning emissions as a significant source of isoprene-derived organosulfates during winter in northern cities of China.
                                            
                                            
                                        Agnesh Panta, Konrad Kandler, Kerstin Schepanski, Andres Alastuey, Pavla Dagsson Waldhauserova, Sylvain Dupont, Melanie Eknayan, Cristina González-Flórez, Adolfo González-Romero, Martina Klose, Mara Montag, Xavier Querol, Jesús Yus-Díez, and Carlos Pérez García-Pando
                                        EGUsphere, https://doi.org/10.5194/egusphere-2025-494, https://doi.org/10.5194/egusphere-2025-494, 2025
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                                                Iceland is among the most active dust source areas in the world. Dust properties are influenced by particle size, mineralogy, shape, and mixing state. This work characterizes freshly emitted individual aerosol particles of Icelandic dust using electron microscopy. Our study provides insights into critical particle-specific information will contribute to better constraining climate models that consider mineralogical variations in their representation of the dust cycle.
                                            
                                            
                                        Xueqin Zheng, Junwen Liu, Nima Chuduo, Bian Ba, Pengfei Yu, Phu Drolgar, Fang Cao, and Yanlin Zhang
                                        EGUsphere, https://doi.org/10.5194/egusphere-2025-164, https://doi.org/10.5194/egusphere-2025-164, 2025
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                                                In this study, we present the first report on the annual variation of stable oxygen isotope anomalies (∆17O = δ17O - 0.52 × δ18O) in NO3- collected from the urban area of Lhasa , on the Tibetan Plateau, China. Using a Bayesian isotope mixture model, we found that the relative contribution of the NO3+VOC pathway to NO3- formation in spring in Lhasa was several times higher than in urban cities, highlighting the significant influence of VOC transported from outside the Tibetan Plateau.
                                            
                                            
                                        Yi-Jia Ma, Yu Xu, Ting Yang, Lin Gui, Hong-Wei Xiao, Hao Xiao, and Hua-Yun Xiao
                                    Atmos. Chem. Phys., 25, 2763–2780, https://doi.org/10.5194/acp-25-2763-2025, https://doi.org/10.5194/acp-25-2763-2025, 2025
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                                                The abundance, potential precursors, and main formation mechanisms of nitrogen-containing organic compounds (NOCs) in PM2.5 during winter were compared among cities with different energy consumption patterns. The aerosol NOC pollution during winter in China is closely associated with the intensity of precursor emissions and the aqueous-phase processes. Our results highlight the importance of emission reduction strategies in controlling aerosol NOCs pollution during winter in China.
                                            
                                            
                                        Dane Blanchard, Mark Gordon, Duc Huy Dang, Paul Andrew Makar, and Julian Aherne
                                    Atmos. Chem. Phys., 25, 2423–2442, https://doi.org/10.5194/acp-25-2423-2025, https://doi.org/10.5194/acp-25-2423-2025, 2025
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                                                This study offers the first known evaluation of water-soluble brown carbon aerosols in the Athabasca oil sands region (AOSR), Canada. Fluorescence spectroscopy analysis of aerosol samples from five regional sites (collected during the summer of 2021) identified oil sands operations as a measurable brown carbon source. Industrial aerosol emissions were unlikely to impact regional radiative forcing. These findings show that fluorescence spectroscopy can be used to monitor brown carbon in the AOSR.
                                            
                                            
                                        Kira Zeider, Kayla McCauley, Sanja Dmitrovic, Leong Wai Siu, Yonghoon Choi, Ewan C. Crosbie, Joshua P. DiGangi, Glenn S. Diskin, Simon Kirschler, John B. Nowak, Michael A. Shook, Kenneth L. Thornhill, Christiane Voigt, Edward L. Winstead, Luke D. Ziemba, Paquita Zuidema, and Armin Sorooshian
                                    Atmos. Chem. Phys., 25, 2407–2422, https://doi.org/10.5194/acp-25-2407-2025, https://doi.org/10.5194/acp-25-2407-2025, 2025
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                                                In situ aircraft data collected over the northwest Atlantic Ocean are utilized to compare aerosol conditions and turbulence between near-surface and below-cloud-base altitudes for different regimes of coupling strength between those two levels, along with how cloud microphysical properties vary across those regimes. Stronger coupling yields more homogenous aerosol structure vertically along with higher cloud drop concentrations and sea salt influence in clouds.
                                            
                                            
                                        Junke Zhang, Xinyi Fu, Chunying Chen, Yunfei Su, Siyu Liu, Luyao Chen, Yubao Chen, Gehui Wang, and Andre S. H. Prevot
                                        EGUsphere, https://doi.org/10.5194/egusphere-2025-92, https://doi.org/10.5194/egusphere-2025-92, 2025
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                                                The 125 organic aerosol (OA) compounds in PM2.5 in winter in Chengdu were measured at the molecular level. OA was dominated by fatty acids, phthalate esters, and anhydrosugars, and were deeply influenced by anthropogenic sources. As pollution worsens: secondary inorganic species and secondary organic carbon (OC) dominated the increase in PM2.5; fatty acids and anhydrosugars dominated the increase in OA; and the contribution of secondary formation and biomass burning to OC increased markedly.
                                            
                                            
                                        Amie Dobracki, Ernie R. Lewis, Arthur J. Sedlacek III, Tyler Tatro, Maria A. Zawadowicz, and Paquita Zuidema
                                    Atmos. Chem. Phys., 25, 2333–2363, https://doi.org/10.5194/acp-25-2333-2025, https://doi.org/10.5194/acp-25-2333-2025, 2025
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                                                Biomass-burning aerosol is commonly present in the marine boundary layer over the southeast Atlantic Ocean between June and October. Our research indicates that burning conditions, aerosol transport pathways, and prolonged oxidation processes (heterogeneous and aqueous phases) determine the chemical, microphysical, and optical properties of the boundary layer aerosol. Notably, we find that the aerosol optical properties can be estimated from the chemical properties alone.
                                            
                                            
                                        Benjamin Heutte, Nora Bergner, Hélène Angot, Jakob B. Pernov, Lubna Dada, Jessica A. Mirrielees, Ivo Beck, Andrea Baccarini, Matthew Boyer, Jessie M. Creamean, Kaspar R. Daellenbach, Imad El Haddad, Markus M. Frey, Silvia Henning, Tiia Laurila, Vaios Moschos, Tuukka Petäjä, Kerri A. Pratt, Lauriane L. J. Quéléver, Matthew D. Shupe, Paul Zieger, Tuija Jokinen, and Julia Schmale
                                    Atmos. Chem. Phys., 25, 2207–2241, https://doi.org/10.5194/acp-25-2207-2025, https://doi.org/10.5194/acp-25-2207-2025, 2025
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                                                Limited aerosol measurements in the central Arctic hinder our understanding of aerosol–climate interactions in the region. Our year-long observations of aerosol physicochemical properties during the MOSAiC expedition reveal strong seasonal variations in aerosol chemical composition, where the short-term variability is heavily affected by storms in the Arctic. Local wind-generated particles are shown to be an important source of cloud seeds, especially in autumn.
                                            
                                            
                                        Feng Jiang, Harald Saathoff, Uzoamaka Ezenobi, Junwei Song, Hengheng Zhang, Linyu Gao, and Thomas Leisner
                                    Atmos. Chem. Phys., 25, 1917–1930, https://doi.org/10.5194/acp-25-1917-2025, https://doi.org/10.5194/acp-25-1917-2025, 2025
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                                                The chemical composition of brown carbon in the particle and gas phase was determined by mass spectrometry. BrC in the gas phase was mainly controlled by secondary formation and particle-to-gas partitioning. BrC in the particle phase was mainly from secondary formation. This work helps to get a better understanding of diurnal variations and the sources of brown carbon aerosol at a rural location in central Europe.
                                            
                                            
                                        Vikram Pratap, Christopher J. Hennigan, Bastian Stieger, Andreas Tilgner, Laurent Poulain, Dominik van Pinxteren, Gerald Spindler, and Hartmut Herrmann
                                        EGUsphere, https://doi.org/10.5194/egusphere-2025-457, https://doi.org/10.5194/egusphere-2025-457, 2025
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                                                In this work, we characterize trends in aerosol pH and its controlling factors over the period of 2010 – 2019 at the Melpitz research station in eastern Germany. We find strong trends in aerosol pH and major inorganic species in response to changing emissions. We conduct a detailed thermodynamic analysis of the aerosol system and discuss implications for controlling PM2.5 in the region.
                                            
                                            
                                        Kohei Sakata, Shotaro Takano, Atsushi Matsuki, Yasuo Takeichi, Hiroshi Tanimoto, Aya Sakaguchi, Minako Kurisu, and Yoshio Takahashi
                                        EGUsphere, https://doi.org/10.5194/egusphere-2025-161, https://doi.org/10.5194/egusphere-2025-161, 2025
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                                                Deposition of aerosol iron (Fe) into the ocean stimulates primary production and influences the global carbon cycle, although the factors governing the aerosol Fe solubility remain uncertain. Our observations in Japan revealed that both mineral dust and anthropogenic aerosols are significant sources of dissolved Fe, and that atmospheric chemical weathering enhances their solubility. This finding is expected to play a crucial role in estimating the supply of dissolved iron to the ocean.
                                            
                                            
                                        Rui Li, Yubing Shen, Yumeng Shao, Yining Gao, Ziwei Yao, Qian Liu, Xing Liu, and Guitao Shi
                                        EGUsphere, https://doi.org/10.5194/egusphere-2024-3740, https://doi.org/10.5194/egusphere-2024-3740, 2025
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                                                It is the first time to reveal the global variations of PAHs derivatives in the marine air. We found that marine aerosols in East China Sea (ECS) and Western Pacific (WP) were significantly affected by coal and engine combustion, while those in Bismarck Sea (BS) and East Australian Sea (EAS) were mainly influenced by wildfire and coal combustion. Antarctic Ocean (AO) was dominated by biomass burning and local shipping emissions. This finding help elucidate the mechanism of global PAH cycle.
                                            
                                            
                                        James Brean, David C. S. Beddows, Eija Asmi, Aki Virkkula, Lauriane L. J. Quéléver, Mikko Sipilä, Floortje Van Den Heuvel, Thomas Lachlan-Cope, Anna Jones, Markus Frey, Angelo Lupi, Jiyeon Park, Young Jun Yoon, Rolf Weller, Giselle L. Marincovich, Gabriela C. Mulena, Roy M. Harrison, and Manuel Dall'Osto
                                    Atmos. Chem. Phys., 25, 1145–1162, https://doi.org/10.5194/acp-25-1145-2025, https://doi.org/10.5194/acp-25-1145-2025, 2025
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                                                Our results emphasise how understanding the geographical variation in surface types across the Antarctic is key to understanding secondary aerosol sources.
                                            
                                            
                                        Adam E. Thomas, Hayley S. Glicker, Alex B. Guenther, Roger Seco, Oscar Vega Bustillos, Julio Tota, Rodrigo A. F. Souza, and James N. Smith
                                    Atmos. Chem. Phys., 25, 959–977, https://doi.org/10.5194/acp-25-959-2025, https://doi.org/10.5194/acp-25-959-2025, 2025
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                                                We present measurements of the organic composition of ultrafine particles collected from the eastern Amazon, an understudied region that is subjected to increasing human influence. We find that while isoprene chemistry is likely significant for ultrafine-particle growth throughout the year, compounds related to other sources, such as biological-spore emissions and biomass burning, exhibit striking seasonal differences, implying extensive variation in regional ultrafine-particle sources.
                                            
                                            
                                        Xiufeng Lian, Yongjiang Xu, Fengxian Liu, Long Peng, Xiaodong Hu, Guigang Tang, Xu Dao, Hui Guo, Liwei Wang, Bo Huang, Chunlei Cheng, Lei Li, Guohua Zhang, Xinhui Bi, Xiaofei Wang, Zhen Zhou, and Mei Li
                                        EGUsphere, https://doi.org/10.5194/egusphere-2024-3469, https://doi.org/10.5194/egusphere-2024-3469, 2025
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                                                In this study, we analyzed the mixing state and atmospheric chemical processes of Pb-rich single particles in Beijing. Then, we focused on analyzing the differences in Pb-rich particles between the heating period and non-heating period, as well as the formation mechanism of lead nitrate after coal-to-gas conversion. Our results highlighted the improvement of coal-to-gas conversion on Pb in the particulate.
                                            
                                            
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                        Altieri, K. E., Turpin, B. J., and Seitzinger, S. P.: Oligomers, organosulfates, and nitrooxy organosulfates in rainwater identified by ultra-high resolution electrospray ionization FT-ICR mass spectrometry, Atmos. Chem. Phys., 9, 2533–2542, https://doi.org/10.5194/acp-9-2533-2009, 2009.
                    
                
                        
                        Anderson, J. O., Thundiyil, J. G., and Stolbach, A.: Clearing the Air: A Review of the Effects of Particulate Matter Air Pollution on Human Health, J. Med. Toxicol., 8, 166–175, https://doi.org/10.1007/s13181-011-0203-1, 2011.
                    
                
                        
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                Short summary
                    Organosulfates are components of secondary organic aerosol (SOA) formed in the presence of sulfate. Herein, their abundance, identity, and potential to form as sampling artifacts were studied in Centreville, AL, USA. The 10 most abundant signals accounted for 58–78 % of the total, with at least 20–200 other species accounting for the remainder. These major species were largely associated with biogenic gases, like isoprene and monoterpenes, and are proposed targets for future standard development.
                    Organosulfates are components of secondary organic aerosol (SOA) formed in the presence of...
                    
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