Articles | Volume 14, issue 22
Research article 19 Nov 2014
Research article | 19 Nov 2014
Atmospheric amines and ammonia measured with a chemical ionization mass spectrometer (CIMS)
Y. You et al.
No articles found.
Demetrios Pagonis, Pedro Campuzano-Jost, Hongyu Guo, Douglas A. Day, Melinda K. Schueneman, Wyatt L. Brown, Benjamin A. Nault, Harald Stark, Kyla Siemens, Alex Laskin, Felix Piel, Laura Tomsche, Armin Wisthaler, Matthew M. Coggon, Georgios I. Gkatzelis, Hannah S. Halliday, Jordan E. Krechmer, Richard H. Moore, David S. Thomson, Carsten Warneke, Elizabeth B. Wiggins, and Jose L. Jimenez
Atmos. Meas. Tech., 14, 1545–1559,Short summary
We describe the airborne deployment of an extractive electrospray time-of-flight mass spectrometer (EESI-MS). The instrument provides a quantitative 1 Hz measurement of the chemical composition of organic aerosol up to altitudes of 7 km, with single-compound detection limits as low as 50 ng per standard cubic meter.
Beata Opacka, Jean-François Müller, Trissevgeni Stavrakou, Maite Bauwens, Katerina Sindelarova, Jana Markova, and Alex B. Guenther
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
Isoprene is primarily emitted from plants and about 80 % of its global emissions occur in the Tropics. Current isoprene inventories are usually based on modelled vegetation maps. But high pressure on land use over the last decades lead to severe losses, especially in tropical forests, that are not considered by models. We provide a study on the present-day impact of spaceborne land cover changes on isoprene emissions and the first inventory based on high-resolution Landsat tree cover dataset.
Yilin Chen, Huizhong Shen, Jennifer Kaiser, Yongtao Hu, Shannon L. Capps, Shunliu Zhao, Amir Hakami, Jhih-Shyang Shih, Gertrude K. Pavur, Matthew D. Turner, Daven K. Henze, Jaroslav Resler, Athanasios Nenes, Sergey L. Napelenok, Jesse O. Bash, Kathleen M. Fahey, Gregory R. Carmichael, Tianfeng Chai, Lieven Clarisse, Pierre-François Coheur, Martin Van Damme, and Armistead G. Russell
Atmos. Chem. Phys., 21, 2067–2082,Short summary
Ammonia (NH3) emissions can exert adverse impacts on air quality and ecosystem well-being. NH3 emission inventories are viewed as highly uncertain. Here we optimize the NH3 emission estimates in the US using an air quality model and NH3 measurements from the IASI satellite instruments. The optimized NH3 emissions are much higher than the National Emissions Inventory estimates in April. The optimized NH3 emissions improved model performance when evaluated against independent observation.
Jens Redemann, Robert Wood, Paquita Zuidema, Sarah J. Doherty, Bernadette Luna, Samuel E. LeBlanc, Michael S. Diamond, Yohei Shinozuka, Ian Y. Chang, Rei Ueyama, Leonhard Pfister, Ju-Mee Ryoo, Amie N. Dobracki, Arlindo M. da Silva, Karla M. Longo, Meloë S. Kacenelenbogen, Connor J. Flynn, Kristina Pistone, Nichola M. Knox, Stuart J. Piketh, James M. Haywood, Paola Formenti, Marc Mallet, Philip Stier, Andrew S. Ackerman, Susanne E. Bauer, Ann M. Fridlind, Gregory R. Carmichael, Pablo E. Saide, Gonzalo A. Ferrada, Steven G. Howell, Steffen Freitag, Brian Cairns, Brent N. Holben, Kirk D. Knobelspiesse, Simone Tanelli, Tristan S. L'Ecuyer, Andrew M. Dzambo, Ousmane O. Sy, Greg M. McFarquhar, Michael R. Poellot, Siddhant Gupta, Joseph R. O'Brien, Athanasios Nenes, Mary Kacarab, Jenny P. S. Wong, Jennifer D. Small-Griswold, Kenneth L. Thornhill, David Noone, James R. Podolske, K. Sebastian Schmidt, Peter Pilewskie, Hong Chen, Sabrina P. Cochrane, Arthur J. Sedlacek, Timothy J. Lang, Eric Stith, Michal Segal-Rozenhaimer, Richard A. Ferrare, Sharon P. Burton, Chris A. Hostetler, David J. Diner, Felix C. Seidel, Steven E. Platnick, Jeffrey S. Myers, Kerry G. Meyer, Douglas A. Spangenberg, Hal Maring, and Lan Gao
Atmos. Chem. Phys., 21, 1507–1563,Short summary
Southern Africa produces significant biomass burning emissions whose impacts on regional and global climate are poorly understood. ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) is a 5-year NASA investigation designed to study the key processes that determine these climate impacts. The main purpose of this paper is to familiarize the broader scientific community with the ORACLES project, the dataset it produced, and the most important initial findings.
Andreas Tilgner, Thomas Schaefer, Becky Alexander, Mary Barth, Jeffrey L. Collett Jr., Kathleen M. Fahey, Athanasios Nenes, Havala O. T. Pye, Hartmut Herrmann, and V. Faye McNeill
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
Feedbacks of acidity and atmospheric multiphase chemistry in deliquesced particles and clouds are crucial for the tropospheric composition, depositions, climate, and human health. This review synthesizes the current scientific knowledge on these feedbacks involving both inorganic and organic aqueous-phase chemistry. Finally, this review outlines atmospheric implications and highlight needs for future investigations with respect to reducing emissions of key acid precursors in a changing world.
Stylianos Kakavas, David Patoulias, Maria Zakoura, Athanasios Nenes, and Spyros N. Pandis
Atmos. Chem. Phys., 21, 799–811,Short summary
The dependence of aerosol acidity on particle size, location, and altitude over Europe during a summertime period is investigated. Differences of up to 1–4 pH units are predicted between sub- and supermicron particles in northern and southern Europe. Particles of all sizes become increasingly acidic with altitude (0.5–2.5 pH units decrease over 2.5 km). The size-dependent pH differences carry important implications for pH-sensitive processes in the aerosol.
Georgia Sotiropoulou, Étienne Vignon, Gillian Young, Hugh Morrison, Sebastian J. O'Shea, Thomas Lachlan-Cope, Alexis Berne, and Athanasios Nenes
Atmos. Chem. Phys., 21, 755–771,Short summary
Summer clouds have a significant impact on the radiation budget of the Antarctic surface and thus on ice-shelf melting. However, these are poorly represented in climate models due to errors in their microphysical structure, including the number of ice crystals that they contain. We show that breakup from ice particle collisions can substantially magnify the ice crystal number concentration with significant implications for surface radiation. This process is currently missing in climate models.
Alexandra J. Boris, Satoshi Takahama, Andrew T. Weakley, Bruno M. Debus, Stephanie L. Shaw, Eric S. Edgerton, Taekyu Joo, Nga L. Ng, and Ann M. Dillner
Atmos. Meas. Tech. Discuss.,
Preprint under review for AMTShort summary
Infrared spectrometry can be applied in routine monitoring of atmospheric particles to give comprehensive characterization of the organic material by bond rather than species. Using this technique, the concentrations of particle organic material were found to decrease 2011–2016 in the Southeastern U.S., driven by a decline in highly aged material, concurrent with declining anthropogenic emissions. However, an increase was observed in the fraction of more moderately aged organic matter.
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,Short summary
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.
Michael J. Lawler, Savannah L. Lewis, Lynn M. Russell, Patricia K. Quinn, Timothy S. Bates, Derek J. Coffman, Lucia M. Upchurch, and Eric S. Saltzman
Atmos. Chem. Phys., 20, 16007–16022,Short summary
This work describes new measurements of aerosol (particles) composition over the North Atlantic Ocean. It provides concentrations of polysaccharide material likely made from organisms in the surface ocean and improves our understanding of the relative importance of such fresh biogenic material compared to more recalcitrant organic carbon in forming marine organic aerosol. We aim ultimately to understand the role that ocean biology plays in cloud formation in marine regions.
Johannes Quaas, Antti Arola, Brian Cairns, Matthew Christensen, Hartwig Deneke, Annica M. L. Ekman, Graham Feingold, Ann Fridlind, Edward Gryspeerdt, Otto Hasekamp, Zhanqing Li, Antti Lipponen, Po-Lun Ma, Johannes Mülmenstädt, Athanasios Nenes, Joyce E. Penner, Daniel Rosenfeld, Roland Schrödner, Kenneth Sinclair, Odran Sourdeval, Philip Stier, Matthias Tesche, Bastiaan van Diedenhoven, and Manfred Wendisch
Atmos. Chem. Phys., 20, 15079–15099,Short summary
Anthropogenic pollution particles – aerosols – serve as cloud condensation nuclei and thus increase cloud droplet concentration and the clouds' reflection of sunlight (a cooling effect on climate). This Twomey effect is poorly constrained by models and requires satellite data for better quantification. The review summarizes the challenges in properly doing so and outlines avenues for progress towards a better use of aerosol retrievals and better retrievals of droplet concentrations.
Paraskevi Georgakaki, Aikaterini Bougiatioti, Jörg Wieder, Claudia Mignani, Fabiola Ramelli, Zamin A. Kanji, Jan Henneberger, Maxime Hervo, Alexis Berne, Ulrike Lohmann, and Athanasios Nenes
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
Aerosol and cloud observations coupled with a droplet activation parameterization was used to investigate the aerosol-cloud droplet link in mixed-phase Alpine clouds. Predicted droplet number, Nd, agrees with observations, and never exceeds a characteristic
limiting droplet number, Ndlim, which depends solely on σw. Nd becomes velocity-limited when it is to within 50 % of Ndlim. Identifying when dynamical changes control Nd variability is central for understanding aerosol-cloud interactions.
Benjamin A. Nault, Pedro Campuzano-Jost, Douglas A. Day, Hongyu Guo, Duseong S. Jo, Anne V. Handschy, Demetrios Pagonis, Jason C. Schroder, Melinda K. Schueneman, Michael J. Cubison, Jack E. Dibb, Alma Hodzic, Weiwei Hu, Brett B. Palm, and Jose L. Jimenez
Atmos. Meas. Tech., 13, 6193–6213,Short summary
Collecting particulate matter, or aerosols, onto filters to be analyzed offline is a widely used method to investigate the mass concentration and chemical composition of the aerosol, especially the inorganic portion. Here, we show that acidic aerosol (sulfuric acid) collected onto filters and then exposed to high ammonia mixing ratios (from human emissions) will lead to biases in the ammonium collected onto filters, and the uptake of ammonia is rapid (< 10 s), which impacts the filter data.
Ari Laaksonen, Jussi Malila, and Athanasios Nenes
Atmos. Chem. Phys., 20, 13579–13589,Short summary
Aerosol particles containing black carbon are ubiquitous in the atmosphere and originate from combustion processes. We examine their capability to act as condensation centers for water vapor. We make use of published experimental data sets for different types of black carbon particles, ranging from very pure particles to particles that contain both black carbon and water soluble organic matter, and we show that a recently developed theory reproduces most of the experimental results.
Lanxiadi Chen, Chao Peng, Wenjun Gu, Hanjing Fu, Xing Jian, Huanhuan Zhang, Guohua Zhang, Jianxi Zhu, Xinming Wang, and Mingjin Tang
Atmos. Chem. Phys., 20, 13611–13626,Short summary
We investigated hygroscopic properties of a number of mineral dust particles in a quantitative manner, via measuring the sample mass at different relative humidities. The robust and comprehensive data obtained would significantly improve our knowledge of hygroscopicity of mineral dust and its impacts on atmospheric chemistry and climate.
Jake P. Rowe, Andrew T. Lambe, and William H. Brune
Atmos. Chem. Phys., 20, 13417–13424,Short summary
We conducted a series of experiments in which the 185 to 254 nm photon flux ratio (I185 : I254) emitted by low-pressure mercury lamps installed in an oxidation flow reactor (OFR) was systematically varied using multiple novel lamp configurations. Integrated OH exposure values achieved for each lamp type were obtained as a function of OFR operating conditions. A photochemical box model was used to develop a generalized OH exposure estimation equation as a function of [H2O], [O3], and OH reactivity.
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. Discuss.,
Preprint under review for ACPShort summary
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 are predictable and explained by key emissions. These results are used to estimate the premature mortality associated to SOA in urban regions.
Yiqi Zheng, Joel A. Thornton, Nga Lee Ng, Hansen Cao, Daven K. Henze, Erin E. McDuffie, Weiwei Hu, Jose L. Jimenez, Eloise A. Marais, Eric Edgerton, and Jingqiu Mao
Atmos. Chem. Phys., 20, 13091–13107,Short summary
This study aims to address a challenge in biosphere–atmosphere interactions: to what extent can biogenic organic aerosol (OA) be modified through human activities? From three surface network observations, we show OA is weakly dependent on sulfate and aerosol acidity in the summer southeast US, on both long-term trends and monthly variability. The results are in strong contrast to a global model, GEOS-Chem, suggesting the need to revisit the representation of aqueous-phase secondary OA formation.
Chen Dayan, Erick Fredj, Pawel K. Misztal, Maor Gabay, Alex B. Guenther, and Eran Tas
Atmos. Chem. Phys., 20, 12741–12759,Short summary
We studied the emission of biogenic volatile organic compounds from both marine and terrestrial ecosystems in the Eastern Mediterranean Basin, a global warming hot spot. We focused on isoprene and dimethyl sulfide (DMS), which are well recognized for their effect on climate and strong impact on photochemical pollution by the former. We found high emissions of isoprene and a strong decadal decrease in the emission of DMS which can both be attributed to the strong increase in seawater temperature.
Chinmoy Sarkar, Gracie Wong, Anne Mielnik, Alex B. Guenther, Taehyung Lee, Taehyun Park, Jihee Ban, Seokwon Kang, Jin-Soo Park, Joonyoung Ahn, Danbi Kim, Hyunjae Kim, Jinsoo Choi, Beom-Keon Seo, Jong-Ho Kim, Jeong-Ho Kim, Soo Bog Park, and Saewung Kim
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
We present experimental proofs illustrating emission of ketene in an industrial facility in South Korea. It has been rarely reported the emission of such a compound but our experimental data shows that the emission rate is substantial. It potentially has tremendous implication in regional air quality and public health as it is highly reactive and toxic at the sometime.
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,Short summary
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.
Haijie Tong, Fobang Liu, Alexander Filippi, Jake Wilson, Andrea M. Arangio, Yun Zhang, Siyao Yue, Steven Lelieveld, Fangxia Shen, Helmi-Marja K. Keskinen, Jing Li, Haoxuan Chen, Ting Zhang, Thorsten Hoffmann, Pingqing Fu, William H. Brune, Tuukka Petäjä, Markku Kulmala, Maosheng Yao, Thomas Berkemeier, Manabu Shiraiwa, and Ulrich Pöschl
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
We measured radical yields of aqueous PM2.5 extracts and found lower yields at higher concentrations of PM2.5. Abundances of water-soluble transition metals and aromatics in PM2.5 were positively correlated with the relative fraction (RF) of •OH among detected radicals, but negatively correlated with the RF of C-centered radicals. Composition-dependent reactive species yields may explain differences in the reactivity and health effects of PM2.5 in clean versus polluted air.
Georgia Sotiropoulou, Luisa Ickes, Athanasios Nenes, and Annica M. L. Ekman
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
Mixed-phase clouds are a large source of uncertainty in projections of the Arctic climate. This is partly due to the poor representation of the cloud-ice formation processes. Implementing a parameterization for ice multiplication due to mechanical break-up upon collision of two ice particles in a high resolution model improves cloud-ice phase representation. However, the results are sensitive to poorly constrained microphysical parameters (e.g. ice habit, rimed fraction, autoconversion rate).
Amir Yazdani, Nikunj Dudani, Satoshi Takahama, Amelie Bertrand, André S. H. Prévôt, Imad El Haddad, and Ann M. Dillner
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
Functional group composition of primary and aged aerosols from wood burning and coal combustion sources from chamber experiments are interpreted through compounds present in the fuels and known gas-phase oxidation products. Infrared spectra of aged wood burning in the chamber and ambient biomass burning samples reveal striking similarities, and a new method for identifying burning-impacted samples in monitoring network measurements is presented.
Archit Mehra, Jordan E. Krechmer, Andrew Lambe, Chinmoy Sarkar, Leah Williams, Farzaneh Khalaj, Alex Guenther, John Jayne, Hugh Coe, Douglas Worsnop, Celia Faiola, and Manjula Canagaratna
Atmos. Chem. Phys., 20, 10953–10965,Short summary
Emissions of volatile organic compounds (VOCs) from plants are important for tropospheric ozone and secondary organic aerosol (SOA) formation. Real plant emissions are much more diverse than the few proxies widely used for studies of plant SOA. Here we present the first study of SOA from Californian sage plants and the oxygenated monoterpenes representing their major emissions. We identify SOA products and show the importance of the formation of highly oxygenated organic molecules and oligomers.
Yutong Liang, Coty N. Jen, Robert J. Weber, Pawel K. Misztal, and Allen H. Goldstein
Atmos. Chem. Phys. Discuss.,
Revised manuscript under review for ACPShort summary
This article reports the molecular composition of smoke particles people in SF Bay Area were exposed to during northern California wildfires Oct. 2017. Major components include 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. Statistical analysis reveals a group of secondary compounds formed in daytime aging.
Bingqing Zhang, Huizhong Shen, Pengfei Liu, Hongyu Guo, Yongtao Hu, Yilin Chen, Shaodong Xie, Ziyan Xi, and Armistead G. Russell
Atmos. Chem. Phys. Discuss.,
Revised manuscript under review for ACPShort summary
Large-scale ground-level measurements are coupled with model simulations to comprehensively compare the aerosol acidity in China and the United States. Aerosol in China is significantly less acidic than that in the United States, with pH values 1–2 units higher. The abundance of ammonia and ammonium in China is the leading cause of the pH difference, and the large difference indicates potential distinctions in aerosol formation, composition, and toxicity between these two countries.
Eirini Boleti, Christoph Hueglin, Stuart K. Grange, André S. H. Prévôt, and Satoshi Takahama
Atmos. Chem. Phys., 20, 9051–9066,Short summary
Long-term temporal evolution of ozone concentrations between 2000 and 2015 in Europe was estimated using a signal decomposition technique. The seasonal cycles are correlated with local climate conditions and vary according to geographic region, while ozone levels are indicative of distance to emission sources. The site's environment plays a key role in ozone trends, with the most polluted environments showing the least reduction in ozone, while in less polluted areas ozone has decreased.
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,Short summary
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,Short summary
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.
Ifayoyinsola Ibikunle, Andreas Beyersdorf, Pedro Campuzano-Jost, Chelsea Corr, John D. Crounse, Jack Dibb, Glenn Diskin, Greg Huey, Jose-Luis Jimenez, Michelle J. Kim, Benjamin A. Nault, Eric Scheuer, Alex Teng, Paul O. Wennberg, Bruce Anderson, James Crawford, Rodney Weber, and Athanasios Nenes
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
Analysis of observations over South Korea during the NASA/NIER KORUS-AQ field campaign show that aerosol is fairly acidic (mean pH 2.43 ± 0.68). Aerosol formation is always sensitive to HNO3 levels, especially in highly polluted regions, while it is only exclusively sensitive to NH3 in some rural/remote regions. Nitrate levels accumulate because dry deposition velocity is low. HNO3 reductions achieved by NOx controls can be the most effective PM reduction strategy for all conditions observed.
Yunle Chen, Masayuki Takeuchi, Theodora Nah, Lu Xu, Manjula R. Canagaratna, Harald Stark, Karsten Baumann, Francesco Canonaco, André S. H. Prévôt, L. Gregory Huey, Rodney J. Weber, and Nga L. Ng
Atmos. Chem. Phys., 20, 8421–8440,Short summary
Two online mass spectrometry instruments, an aerosol mass spectrometer and a chemical ionization mass spectrometer equipped with a filter inlet for gases and aerosols, were deployed at Yorkville, GA, for a comprehensive characterization of organic aerosol. We observed notable secondary organic aerosol formation from isoprene and monoterpenes via different pathways during both day and night, and a series of highly oxidized acid-like compounds was found to be closely related to aged SOA.
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,Short summary
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.
Katherine R. Travis, Colette L. Heald, Hannah M. Allen, Eric C. Apel, Stephen R. Arnold, Donald R. Blake, William H. Brune, Xin Chen, Róisín Commane, John D. Crounse, Bruce C. Daube, Glenn S. Diskin, James W. Elkins, Mathew J. Evans, Samuel R. Hall, Eric J. Hintsa, Rebecca S. Hornbrook, Prasad S. Kasibhatla, Michelle J. Kim, Gan Luo, Kathryn McKain, Dylan B. Millet, Fred L. Moore, Jeffrey Peischl, Thomas B. Ryerson, Tomás Sherwen, Alexander B. Thames, Kirk Ullmann, Xuan Wang, Paul O. Wennberg, Glenn M. Wolfe, and Fangqun Yu
Atmos. Chem. Phys., 20, 7753–7781,Short summary
Atmospheric models overestimate the rate of removal of trace gases by the hydroxyl radical (OH). This is a concern for studies of the climate and air quality impacts of human activities. Here, we evaluate the performance of a commonly used model of atmospheric chemistry against data from the NASA Atmospheric Tomography Mission (ATom) over the remote oceans where models have received little validation. The model is generally successful, suggesting that biases in OH may be a concern over land.
Shunliu Zhao, Matthew G. Russell, Amir Hakami, Shannon L. Capps, Matthew D. Turner, Daven K. Henze, Peter B. Percell, Jaroslav Resler, Huizhong Shen, Armistead G. Russell, Athanasios Nenes, Amanda J. Pappin, Sergey L. Napelenok, Jesse O. Bash, Kathleen M. Fahey, Gregory R. Carmichael, Charles O. Stanier, and Tianfeng Chai
Geosci. Model Dev., 13, 2925–2944,
Jian Xu, Jia Chen, Na Zhao, Guochen Wang, Guangyuan Yu, Hao Li, Juntao Huo, Yanfen Lin, Qingyan Fu, Hongyu Guo, Congrui Deng, Shan-Hu Lee, Jianmin Chen, and Kan Huang
Atmos. Chem. Phys., 20, 7259–7269,Short summary
This study provided evidence that gas-particle partitioning of ammonia, as opposed to ammonia concentration, plays a critical role in the haze formation. A reduction in ammonia emissions alone may not reduce air pollution effectively, at least at rural agricultural sites in China.
Chinmoy Sarkar, Alex B. Guenther, Jeong-Hoo Park, Roger Seco, Eliane Alves, Sarah Batalha, Raoni Santana, Saewung Kim, James Smith, Julio Tóta, and Oscar Vega
Atmos. Chem. Phys., 20, 7179–7191,Short summary
Biogenic volatile organic compounds (BVOCs) are important components of the atmosphere due to their contribution to atmospheric chemistry and biogeochemical cycles. In this study, we report major BVOCs, e.g. isoprene and total monoterpene flux measurements with a proton transfer reaction time-of-flight mass spectrometer (PTR-TOF-MS) using the eddy covariance (EC) method at a primary rainforest in eastern Amazonia. We used the measured data to evaluate the MEGAN2.1 model for the emission site.
Hongyu Guo, Pedro Campuzano-Jost, Benjamin A. Nault, Douglas A. Day, Jason C. Schroder, Jack E. Dibb, Maximilian Dollner, Bernadett Weinzierl, and Jose L. Jimenez
Atmos. Meas. Tech. Discuss.,
Preprint under review for AMTShort summary
We utilize a set of high-quality datasets collected during the NASA ATom aircraft mission to investigate the impact of differences in observable particle sizes across aerosol instruments, in aerosol measurement comparisons. Very good agreement was found between chemically and physically derived submicron aerosol volume. Results support a lack of significant unknown biases in the response of Aerodyne Aerosol Mass Spectrometer (AMS) when sampling remote aerosols across the globe.
Sam J. Silva, Colette L. Heald, and Alex B. Guenther
Geosci. Model Dev., 13, 2569–2585,Short summary
Simulating the influence of the biosphere on atmospheric chemistry has traditionally been computationally intensive. We describe a surrogate canopy physics model parameterized using a statistical learning technique and specifically designed for use in large-scale chemical transport models. Our surrogate model reproduces a more detailed model to within 10 % without a large computational demand, improving the process representation of biosphere–atmosphere exchange.
Camille Mouchel-Vallon, Julia Lee-Taylor, Alma Hodzic, Paulo Artaxo, Bernard Aumont, Marie Camredon, David Gurarie, Jose-Luis Jimenez, Donald H. Lenschow, Scot T. Martin, Janaina Nascimento, John J. Orlando, Brett B. Palm, John E. Shilling, Manish Shrivastava, and Sasha Madronich
Atmos. Chem. Phys., 20, 5995–6014,Short summary
The GoAmazon 2014/5 field campaign took place near the city of Manaus, Brazil, isolated in the Amazon rainforest, to study the impacts of urban pollution on natural air masses. We simulated this campaign with an extremely detailed organic chemistry model to understand how the city would affect the growth and composition of natural aerosol particles. Discrepancies between the model and the measurements indicate that the chemistry of naturally emitted organic compounds is still poorly understood.
Dong Gao, Krystal J. Godri Pollitt, James A. Mulholland, Armistead G. Russell, and Rodney J. Weber
Atmos. Chem. Phys., 20, 5197–5210,Short summary
This study provides a direct intercomparison between two assays for quantifying oxidative potential (OP) of ambient particles: the synthetic respiratory-tract-lining fluid (RTLF) assay and the dithiothreitol (DTT) assay. The results suggest that the DTT assay and the ascorbic acid depletion in RTLF are associated with organic species, transition metal ions, and antagonistic interactions between species. The glutathione depletion in RTLF is strongly dependent on water-soluble copper.
Havala O. T. Pye, Athanasios Nenes, Becky Alexander, Andrew P. Ault, Mary C. Barth, Simon L. Clegg, Jeffrey L. Collett Jr., Kathleen M. Fahey, Christopher J. Hennigan, Hartmut Herrmann, Maria Kanakidou, James T. Kelly, I-Ting Ku, V. Faye McNeill, Nicole Riemer, Thomas Schaefer, Guoliang Shi, Andreas Tilgner, John T. Walker, Tao Wang, Rodney Weber, Jia Xing, Rahul A. Zaveri, and Andreas Zuend
Atmos. Chem. Phys., 20, 4809–4888,Short summary
Acid rain is recognized for its impacts on human health and ecosystems, and programs to mitigate these effects have had implications for atmospheric acidity. Historical measurements indicate that cloud and fog droplet acidity has changed in recent decades in response to controls on emissions from human activity, while the limited trend data for suspended particles indicate acidity may be relatively constant. This review synthesizes knowledge on the acidity of atmospheric particles and clouds.
Alexander B. Thames, William H. Brune, David O. Miller, Hannah M. Allen, Eric C. Apel, Donald R. Blake, T. Paul Bui, Roisin Commane, John D. Crounse, Bruce C. Daube, Glenn S. Diskin, Joshua P. DiGangi, James W. Elkins, Samuel R. Hall, Thomas F. Hanisco, Reem A. Hannun, Eric Hintsa, Rebecca S. Hornbrook, Michelle J. Kim, Kathryn McKain, Fred L. Moore, Julie M. Nicely, Jeffrey Peischl, Thomas B. Ryerson, Jason M. St. Clair, Colm Sweeney, Alex Teng, Chelsea R. Thompson, Kirk Ullmann, Paul O. Wennberg, and Glenn M. Wolfe
Atmos. Chem. Phys., 20, 4013–4029,Short summary
Oceans and the atmosphere exchange volatile gases that react with the hydroxyl radical (OH). During a NASA airborne study, measurements of the total frequency of OH reactions, called the OH reactivity, were made in the marine boundary layer of the Atlantic and Pacific oceans. The measured OH reactivity often exceeded the OH reactivity calculated from measured chemical species. This missing OH reactivity appears to be from unmeasured volatile organic compounds coming out of the ocean.
Charlotte Bürki, Matteo Reggente, Ann M. Dillner, Jenny L. Hand, Stephanie L. Shaw, and Satoshi Takahama
Atmos. Meas. Tech., 13, 1517–1538,Short summary
Infrared spectroscopy is a chemically informative method for particulate matter characterization. However, recent work has demonstrated that predictions depend heavily on the choice of calibration model parameters. We propose a means for managing parameter uncertainties by combining available data from laboratory standards, molecular databases, and collocated ambient measurements to provide useful characterization of atmospheric organic matter on a large scale.
Athanasios Nenes, Spyros N. Pandis, Maria Kanakidou, Armistead Russell, Shaojie Song, Petros Vasilakos, and Rodney J. Weber
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
Ecosystems and air quality are affected by the dry deposition of inorganic reactive nitrogen (Nr, the sum of ammonium and nitrate). Its large variability is driven by the large difference in deposition velocity of N when in the gas or particle phase. Here we show that aerosol liquid water and acidity, by affecting gas-particle partitioning, modulate the dry deposition velocity of NH3, HNO3 and Nr worldwide. These effects explain the rapid accumulation of nitrate aerosol during haze events.
Dianne Sanchez, Roger Seco, Dasa Gu, Alex Guenther, John Mak, Youngjae Lee, Danbi Kim, Joonyoung Ahn, Don Blake, Scott Herndon, Daun Jeong, John T. Sullivan, Thomas Mcgee, and Saewung Kim
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACP
Amir Yazdani, Ann M. Dillner, and Satoshi Takahama
Atmos. Meas. Tech. Discuss.,
Revised manuscript accepted for AMTShort summary
We propose a spectroscopic method for estimating several mixture-averaged molecular properties (carbon number and molecular weight) in particulate matter relevant for understanding its chemical origins. This estimation is enabled by calibration models built and tested using laboratory standards containing molecules with known structure, and can be applied to filter samples of PM2.5 currently collected in existing air pollution monitoring networks and field campaigns.
Athanasios Nenes, Spyros N. Pandis, Rodney J. Weber, and Armistead Russell
Atmos. Chem. Phys., 20, 3249–3258,Short summary
We show that aerosol acidity (pH) and liquid water content naturally emerge as previously ignored parameters that drive particulate matter formation in the atmosphere, and its sensitivity to emissions of ammonia and nitric acid. The simple framework presented is easily applied to ambient measurements or model output, and it provides the
chemical regimeof PM sensitivity to ammonia and nitric acid availability.
Hui Wang, Qizhong Wu, Alex B. Guenther, Xiaochun Yang, Lanning Wang, Tang Xiao, Jie Li, Jinming Feng, Qi Xu, and Huaqiong Cheng
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
We assessed the influence of greening trend on BVOCs emission and found that the land cover change dominated the significantly increasing trend of 1.09 % yr−1 of BVOCs emission in China. In the Qinling Mountains and in the south of China, the BVOC emission for the year 2016 were enhanced by 61.89 % and 67.64 % compared to that of 2001, respectively. The continued increase of BVOC will enhance its importance when making policies for controlling ozone pollution in China.
Mary Kacarab, K. Lee Thornhill, Amie Dobracki, Steven G. Howell, Joseph R. O'Brien, Steffen Freitag, Michael R. Poellot, Robert Wood, Paquita Zuidema, Jens Redemann, and Athanasios Nenes
Atmos. Chem. Phys., 20, 3029–3040,Short summary
We find that extensive biomass burning aerosol plumes from southern Africa can profoundly influence clouds in the southeastern Atlantic. Concurrent variations in vertical velocity, however, are found to magnify the relationship between boundary layer aerosol and the cloud droplet number. Neglecting these covariances may strongly bias the sign and magnitude of aerosol impacts on the cloud droplet number.
Aoxing Zhang, Yuhang Wang, Yuzhong Zhang, Rodney J. Weber, Yongjia Song, Ziming Ke, and Yufei Zou
Atmos. Chem. Phys., 20, 1901–1920,Short summary
Black carbon (BC) and brown carbon (BrC) are light-absorbing carbonaceous aerosols. We developed a module to simulate the emissions, atmospheric processing and direct radiative effect of BrC in the Community Earth System Model (CESM). We found that globally BrC is a significant absorber and is more centered in the tropical free troposphere compared to BC. The contribution of BrC heating to the Hadley circulation and latitudinal expansion of the tropics is comparable to BC heating.
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,Short summary
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.
Arnaldo Negron, Natasha DeLeon-Rodriguez, Samantha M. Waters, Luke D. Ziemba, Bruce Anderson, Michael Bergin, Konstantinos T. Konstantinidis, and Athanasios Nenes
Atmos. Chem. Phys., 20, 1817–1838,Short summary
Airborne biological particles impact human health, cloud formation, and ecosystems, but few techniques are available to characterize their atmospheric abundance. Combining a newly developed high-volume sampling/flow cytometry technique together with an laser-induced fluorescence instrument, we detect a highly dynamic bioaerosol community over urban Atlanta, composed of pollen, fungi, and bacteria with low and high nucleic acid content.
Georgia Sotiropoulou, Sylvia Sullivan, Julien Savre, Gary Lloyd, Thomas Lachlan-Cope, Annica M. L. Ekman, and Athanasios Nenes
Atmos. Chem. Phys., 20, 1301–1316,Short summary
Arctic clouds constitute a large source of uncertainty in predictions of future climate. Observations indicate that the number concentration of cloud ice crystals exceeds the concentration of aerosols that can act as ice-nucleating particles (INPs). We show that ice multiplication due to mechanical break-up upon collisions between the few primary ice crystals (formed from INPs) can explain the discrepancy. Including a description of the process in climate models can improve cloud representation.
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,Short summary
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,Short summary
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,Short summary
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.
Michael A. Battaglia Jr., Rodney J. Weber, Athanasios Nenes, and Christopher J. Hennigan
Atmos. Chem. Phys., 19, 14607–14620,Short summary
The effects of water-soluble organic carbon (WSOC) on aerosol pH were characterized for aqueous-phase particles containing a mixture of inorganics and organics. The ISORROPIA-II and E-AIM models were used in conjunction with AIOMFAC to quantify the effect of organics on aerosol pH through (1) changes to the aerosol liquid water content and (2) changes to the hydrogen ion activity coefficient. The study included both organic acids and nonacids, at RH levels ranging from 70 to 90 %.
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,Short summary
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.
Hayley S. Glicker, Michael J. Lawler, John Ortega, Suzane S. de Sá, Scot T. Martin, Paulo Artaxo, Oscar Vega Bustillos, Rodrigo de Souza, Julio Tota, Annmarie Carlton, and James N. Smith
Atmos. Chem. Phys., 19, 13053–13066,Short summary
An understanding of the chemical composition of the smallest particles in the air over the Amazon Basin provides insights into the natural and human-caused influences on particle production in this sensitive region. We present measurements of the composition of sub-100 nm diameter particles performed during the wet season and identify unique constituents that point to both natural and human-caused sources and processes.
Daun Jeong, Roger Seco, Dasa Gu, Youngro Lee, Benjamin A. Nault, Christoph J. Knote, Tom Mcgee, John T. Sullivan, Jose L. Jimenez, Pedro Campuzano-Jost, Donald R. Blake, Dianne Sanchez, Alex B. Guenther, David Tanner, L. Gregory Huey, Russell Long, Bruce E. Anderson, Samuel R. Hall, Kirk Ullmann, Hye-jung Shin, Scott C. Herndon, Youngjae Lee, Danbi Kim, Joonyoung Ahn, and Saewung Kim
Atmos. Chem. Phys., 19, 12779–12795,
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,Short summary
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.
Alexandra J. Boris, Satoshi Takahama, Andrew T. Weakley, Bruno M. Debus, Carley D. Fredrickson, Martin Esparza-Sanchez, Charlotte Burki, Matteo Reggente, Stephanie L. Shaw, Eric S. Edgerton, and Ann M. Dillner
Atmos. Meas. Tech., 12, 5391–5415,Short summary
Organic species are abundant in atmospheric particle-phase (aerosol) pollution and originate from a variety of biogenic and anthropogenic sources. Infrared spectrometry of filter-based atmospheric particle samples can afford a direct measurement of the particulate organic matter concentration and a characterization of its composition. This work discusses recent method improvements and compositions measured in samples from the SouthEastern Aerosol Research and Characterization (SEARCH) network.
Eleni Marinou, Matthias Tesche, Athanasios Nenes, Albert Ansmann, Jann Schrod, Dimitra Mamali, Alexandra Tsekeri, Michael Pikridas, Holger Baars, Ronny Engelmann, Kalliopi-Artemis Voudouri, Stavros Solomos, Jean Sciare, Silke Groß, Florian Ewald, and Vassilis Amiridis
Atmos. Chem. Phys., 19, 11315–11342,Short summary
We assess the feasibility of ground-based and spaceborne lidars to retrieve profiles of cloud-relevant aerosol concentrations and ice-nucleating particles. The retrieved profiles are in good agreement with airborne in situ measurements. Our methodology will be applied to satellite observations in the future so as to provide a global 3D product of cloud-relevant properties.
Emma L. D'Ambro, Siegfried Schobesberger, Cassandra J. Gaston, Felipe D. Lopez-Hilfiker, Ben H. Lee, Jiumeng Liu, Alla Zelenyuk, David Bell, Christopher D. Cappa, Taylor Helgestad, Ziyue Li, Alex Guenther, Jian Wang, Matthew Wise, Ryan Caylor, Jason D. Surratt, Theran Riedel, Noora Hyttinen, Vili-Taneli Salo, Galib Hasan, Theo Kurtén, John E. Shilling, and Joel A. Thornton
Atmos. Chem. Phys., 19, 11253–11265,Short summary
Isoprene is the most abundantly emitted reactive organic gas globally, and thus it is important to understand its fate and role in aerosol formation and growth. A major product of its oxidation is an epoxydiol, IEPOX, which can be efficiently taken up by acidic aerosol to generate substantial amounts of secondary organic aerosol (SOA). We present chamber experiments exploring the properties of IEPOX SOA and reconcile discrepancies between field, laboratory, and model studies of this process.
Nanna Myllys, Jakub Kubečka, Vitus Besel, Dina Alfaouri, Tinja Olenius, James Norman Smith, and Monica Passananti
Atmos. Chem. Phys., 19, 9753–9768,Short summary
In atmospheric sulfuric-acid-driven particle formation, bases are able to stabilize the initial molecular clusters and thus enhance particle formation. We have investigated the enhancing potential of different bases in atmospheric particle formation. We show that strong bases with low abundance are likely to dominate electrically neutral particle formation, whereas weak bases with high abundance have a larger role in ion-mediated particle formation.
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,Short summary
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.
Lee Tiszenkel, Chris Stangl, Justin Krasnomowitz, Qi Ouyang, Huan Yu, Michael J. Apsokardu, Murray V. Johnston, and Shan-Hu Lee
Atmos. Chem. Phys., 19, 8915–8929,Short summary
Understanding the processes surrounding the formation and growth of atmospheric aerosol particles is essential for understanding their effects on air quality, human health and cloud formation. Current atmospheric models neglect many essential variables that influence these processes. This study investigates temperature effects on new particle formation and the formation of clusters and their subsequent growth in differing temperature conditions.
George S. Fanourgakis, Maria Kanakidou, Athanasios Nenes, Susanne E. Bauer, Tommi Bergman, Ken S. Carslaw, Alf Grini, Douglas S. Hamilton, Jill S. Johnson, Vlassis A. Karydis, Alf Kirkevåg, John K. Kodros, Ulrike Lohmann, Gan Luo, Risto Makkonen, Hitoshi Matsui, David Neubauer, Jeffrey R. Pierce, Julia Schmale, Philip Stier, Kostas Tsigaridis, Twan van Noije, Hailong Wang, Duncan Watson-Parris, Daniel M. Westervelt, Yang Yang, Masaru Yoshioka, Nikos Daskalakis, Stefano Decesari, Martin Gysel-Beer, Nikos Kalivitis, Xiaohong Liu, Natalie M. Mahowald, Stelios Myriokefalitakis, Roland Schrödner, Maria Sfakianaki, Alexandra P. Tsimpidi, Mingxuan Wu, and Fangqun Yu
Atmos. Chem. Phys., 19, 8591–8617,Short summary
Effects of aerosols on clouds are important for climate studies but are among the largest uncertainties in climate projections. This study evaluates the skill of global models to simulate aerosol, cloud condensation nuclei (CCN) and cloud droplet number concentrations (CDNCs). Model results show reduced spread in CDNC compared to CCN due to the negative correlation between the sensitivities of CDNC to aerosol number concentration (air pollution) and updraft velocity (atmospheric dynamics).
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,Short summary
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.
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,Short summary
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.
Karena A. McKinney, Daniel Wang, Jianhuai Ye, Jean-Baptiste de Fouchier, Patricia C. Guimarães, Carla E. Batista, Rodrigo A. F. Souza, Eliane G. Alves, Dasa Gu, Alex B. Guenther, and Scot T. Martin
Atmos. Meas. Tech., 12, 3123–3135,Short summary
Volatile organic compound (VOC) emissions influence air quality and particulate distributions, particularly in major source regions such as the Amazon. A sampler for collecting VOCs from an unmanned aerial vehicle (UAV) is described. Field tests of its performance and an initial example data set collected in the Amazon are also presented. The low cost, ease of use, and maneuverability of UAVs give this method the potential to significantly advance knowledge of the spatial distribution of VOCs.
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,Short summary
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.
Moshe Shechner, Alex Guenther, Robert Rhew, Asher Wishkerman, Qian Li, Donald Blake, Gil Lerner, and Eran Tas
Atmos. Chem. Phys., 19, 7667–7690,Short summary
Along with other recent studies, our findings point to strong emission of a suite of volatile halogenated organic compounds (VHOCs) from saline soils and salt lakes. Some emitted VHOCs were not known to be emitted from terrestrial sources, and our observations point to apparent new common controls for the emission of several VHOCs. These findings are an important milestone toward a more complete understanding of the effect of VHOCs on atmospheric ozone concentrations and oxidation capacity.
Jenny P. S. Wong, Maria Tsagkaraki, Irini Tsiodra, Nikolaos Mihalopoulos, Kalliopi Violaki, Maria Kanakidou, Jean Sciare, Athanasios Nenes, and Rodney J. Weber
Atmos. Chem. Phys., 19, 7319–7334,Short summary
Biomass burning is a major source of light-absorbing organic species in atmospheric aerosols, and it can play an important role in climate and atmospheric chemistry. Through a combination of laboratory experiments and field observations, this work demonstrated that the light absorption properties of aged biomass burning organic aerosols are dominated by high-molecular-weight compounds. In addition, we found that total hydrated sugars may be a robust tracer for aged biomass burning aerosols.
Panayiotis Kalkavouras, Aikaterini Bougiatioti, Nikos Kalivitis, Iasonas Stavroulas, Maria Tombrou, Athanasios Nenes, and Nikolaos Mihalopoulos
Atmos. Chem. Phys., 19, 6185–6203,Short summary
We study how new particle formation (NPF) events affect clouds throughout the year at a ground site in the E Mediterranean. Using a new tools and evaluation metrics, NPF is found to affect only evening and nocturnal clouds by modestly increasing droplet number by 7 to 12 %. A conventional analysis based on CCN concentration at prescribed supersaturation levels or aerosol size can considerably bias the perceived influence of NPF events on regional clouds, the hydrological cycle, and climate.
Matteo Reggente, Ann M. Dillner, and Satoshi Takahama
Atmos. Meas. Tech., 12, 2287–2312,Short summary
We compare state-of-the-art models for predicting functional group composition in atmospheric particulate matter across urban and rural samples collected in a US monitoring network. While trends across models are consistent, absolute abundances can be sensitive to selection of calibration standards, spectral processing procedures, and calibration algorithms. Recommendations for further method development for reducing uncertainties are outlined.
Matteo Reggente, Rudolf Höhn, and Satoshi Takahama
Atmos. Meas. Tech., 12, 2313–2329,Short summary
The infrared spectra of atmospheric particles are rich in chemical information but require sophisticated statistical methods to extract information on account of their complex absorption profiles. We present an open software suite which makes current algorithms used for analysis of such spectra available to the community, with a browser-based interface for general users and modular architecture that facilitates addition of new methods by developers.
Nønne L. Prisle, Jack J. Lin, Sara Purdue, Haisheng Lin, J. Carson Meredith, and Athanasios Nenes
Atmos. Chem. Phys., 19, 4741–4761,Short summary
We measure surface activity and cloud-forming potential of pollenkitt, an organic mixture coating pollen grains. Cloud droplet formation is affected through both surface tension and bulk depletion, with a consistent particle size-dependent signature. We observe nonideal solution effects in pollenkitt mixtures with ammonium sulfate salt. Our results suggest sensitivity of general water interactions, including cloud formation by pollen and their fragments, to both atmospheric humidity and aging.
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,Short summary
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.
Erik Ahlberg, Axel Eriksson, William H. Brune, Pontus Roldin, and Birgitta Svenningsson
Atmos. Chem. Phys., 19, 2701–2712,Short summary
The effects of wet or dry salt seed particle concentration (ammonium nitrate and ammonium sulphate) on secondary organic aerosol mass yields from a mixture of m-xylene and α-pinene were examined in an oxidation flow reactor. The experiments confirmed that increasing the condensation sink significantly increases the particle mass yields in oxidation flow reactors. Further, wet seed particles increased the particle mass yield by 60 % more than dry particles.
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,Short summary
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.
Nathan J. Janechek, Rachel F. Marek, Nathan Bryngelson, Ashish Singh, Robert L. Bullard, William H. Brune, and Charles O. Stanier
Atmos. Chem. Phys., 19, 1649–1664,Short summary
Cyclic volatile methyl siloxanes (cVMSs) are widely used chemicals in personal care products which can undergo oxidation to generate secondary organic aerosol. In this work, cVMS oxidation aerosols were generated using a photochemical chamber and the physical properties characterized. The aerosol yield, volatility, hygroscopicity, morphology, elemental composition, and proposed parameters for treatment as secondary organic aerosol in atmospheric models are provided.
Xiaoxiao Li, Sabrina Chee, Jiming Hao, Jonathan P. D. Abbatt, Jingkun Jiang, and James N. Smith
Atmos. Chem. Phys., 19, 1555–1570,Short summary
We performed lab experiments to explore the role of relative humidity, RH, in atmospheric monoterpene oxidation and new particle formation. These studies will provide insights into the most important steps in the process, while also more accurately representing the real atmosphere. We found that the detected compounds did not change with RH, and in fact could mostly be fully explained by the autoxidation of organic peroxy radicals followed by bimolecular reactions with other peroxy radicals.
Satoshi Takahama, Ann M. Dillner, Andrew T. Weakley, Matteo Reggente, Charlotte Bürki, Mária Lbadaoui-Darvas, Bruno Debus, Adele Kuzmiakova, and Anthony S. Wexler
Atmos. Meas. Tech., 12, 525–567,Short summary
Mid-infrared spectra of particulate matter (PM) samples are complex but chemically informative and present an opportunity for cost-effective measurement of PM provided that quantitative calibration models can be built. We review an emerging strategy for building statistical calibration models using collocated measurements, interpreting the physical bases for such models and evaluating the suitability of existing calibration models to new samples.
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,Short summary
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,Short summary
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,Short summary
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.
Hongyu Guo, Athanasios Nenes, and Rodney J. Weber
Atmos. Chem. Phys., 18, 17307–17323,Short summary
Overprediction of fine-particle ammonium-sulfate molar ratios (R) by thermodynamic models is suggested as evidence for organic aerosol limiting the condensation of ammonia onto particles, with significant impacts on aerosol chemistry. We find that the effects of small amounts of salt and dust, combined with measurement artifacts, explain the discrepancy in R. These results are highly insensitive to mixing state. This means that aerosol predictions are much more robust than thought before.
Sylvia C. Sullivan, Christian Barthlott, Jonathan Crosier, Ilya Zhukov, Athanasios Nenes, and Corinna Hoose
Atmos. Chem. Phys., 18, 16461–16480,Short summary
Ice crystal formation in clouds can occur via thermodynamic nucleation, but also via mechanical collisions between pre-existing crystals or co-existing droplets. When descriptions of this mechanical ice generation are implemented into the COSMO weather model, we find that the contributions to crystal number from thermodynamic and mechanical processes are of the same order. Mechanical ice generation also intensifies differences in precipitation intensity between dynamic and quiescent regions.
Stelios Myriokefalitakis, Akinori Ito, Maria Kanakidou, Athanasios Nenes, Maarten C. Krol, Natalie M. Mahowald, Rachel A. Scanza, Douglas S. Hamilton, Matthew S. Johnson, Nicholas Meskhidze, Jasper F. Kok, Cecile Guieu, Alex R. Baker, Timothy D. Jickells, Manmohan M. Sarin, Srinivas Bikkina, Rachel Shelley, Andrew Bowie, Morgane M. G. Perron, and Robert A. Duce
Biogeosciences, 15, 6659–6684,Short summary
The first atmospheric iron (Fe) deposition model intercomparison is presented in this study, as a result of the deliberations of the United Nations Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP; http://www.gesamp.org/) Working Group 38. We conclude that model diversity over remote oceans reflects uncertainty in the Fe content parameterizations of dust aerosols, combustion aerosol emissions and the size distribution of transported aerosol Fe.
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,Short summary
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 %.
William H. Brune, Xinrong Ren, Li Zhang, Jingqiu Mao, David O. Miller, Bruce E. Anderson, Donald R. Blake, Ronald C. Cohen, Glenn S. Diskin, Samuel R. Hall, Thomas F. Hanisco, L. Gregory Huey, Benjamin A. Nault, Jeff Peischl, Ilana Pollack, Thomas B. Ryerson, Taylor Shingler, Armin Sorooshian, Kirk Ullmann, Armin Wisthaler, and Paul J. Wooldridge
Atmos. Chem. Phys., 18, 14493–14510,Short summary
Thunderstorms pull in polluted air from near the ground, transport it up through clouds containing lightning, and deposit it at altitudes where airplanes fly. The resulting chemical mixture in this air reacts to form ozone and particles, which affect climate. In this study, aircraft observations of the reactive gases responsible for this chemistry generally agree with modeled values, even in ice clouds. Thus, atmospheric oxidation chemistry appears to be mostly understood for this environment.
Sara Bacer, Sylvia C. Sullivan, Vlassis A. Karydis, Donifan Barahona, Martina Krämer, Athanasios Nenes, Holger Tost, Alexandra P. Tsimpidi, Jos Lelieveld, and Andrea Pozzer
Geosci. Model Dev., 11, 4021–4041,Short summary
The complexity of ice nucleation mechanisms and aerosol--ice interactions makes their representation still challenging in atmospheric models. We have implemented a comprehensive ice crystal formation parameterization in the global chemistry-climate model EMAC to improve the representation of ice crystal number concentrations. The newly implemented parameterization takes into account processes which were previously neglected by the standard version of the model.
Victor Lannuque, Marie Camredon, Florian Couvidat, Alma Hodzic, Richard Valorso, Sasha Madronich, Bertrand Bessagnet, and Bernard Aumont
Atmos. Chem. Phys., 18, 13411–13428,Short summary
Large uncertainties remain in understanding the influence of atmospheric environmental conditions on secondary organic aerosol (SOA) formation, evolution and properties. In this article, the GECKO-A modelling tool has been used in a box model under various environmental conditions to (i) explore the sensitivity of SOA formation and properties to changes on physical and chemical conditions and (ii) develop a volatility-basis-set-type parameterization for air quality models.
Theodora Nah, Yi Ji, David J. Tanner, Hongyu Guo, Amy P. Sullivan, Nga Lee Ng, Rodney J. Weber, and L. Gregory Huey
Atmos. Meas. Tech., 11, 5087–5104,Short summary
The sources and atmospheric chemistry of gas-phase organic acids are currently poorly understood, due in part to the limited range of measurement techniques available. We evaluated the use of SF6− as a sensitive and selective chemical ionization reagent ion for real-time measurements of gas-phase organic acids at a rural site in Yorkville, Georgia. We found that ambient concentrations of organic acids ranged from a few ppt to several ppb, and are dependent on ambient temperature.
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,Short summary
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.
Petros Vasilakos, Armistead Russell, Rodney Weber, and Athanasios Nenes
Atmos. Chem. Phys., 18, 12765–12775,Short summary
In this work, we investigated the role of emission reductions on aerosol acidity and particulate nitrate. We found that models exhibit positive biases in pH predictions, attributed to very high levels of crustal elements (Mg, Ca, K) in model simulations, which in turn led to an increasing aerosol pH trend over the past decade and allowed nitrate to become an important component of aerosol, which is inconsistent with the measurements, highlighting the importance of accurate pH prediction.
Fernando Santos, Karla Longo, Alex Guenther, Saewung Kim, Dasa Gu, Dave Oram, Grant Forster, James Lee, James Hopkins, Joel Brito, and Saulo Freitas
Atmos. Chem. Phys., 18, 12715–12734,Short summary
We investigated the impact of biomass burning on the chemical composition of trace gases in the Amazon. The findings corroborate the influence of biomass burning activity not only on direct emissions of particulate matter but also on the oxidative capacity to produce secondary organic aerosol. The scientists plan to use this information to improve the numerical model simulation with a better representativeness of the chemical processes, which can impact on global climate prediction.
Anna L. Hodshire, Brett B. Palm, M. Lizabeth Alexander, Qijing Bian, Pedro Campuzano-Jost, Eben S. Cross, Douglas A. Day, Suzane S. de Sá, Alex B. Guenther, Armin Hansel, James F. Hunter, Werner Jud, Thomas Karl, Saewung Kim, Jesse H. Kroll, Jeong-Hoo Park, Zhe Peng, Roger Seco, James N. Smith, Jose L. Jimenez, and Jeffrey R. Pierce
Atmos. Chem. Phys., 18, 12433–12460,Short summary
We investigate the nucleation and growth processes that shape the aerosol size distribution inside oxidation flow reactors (OFRs) that sampled ambient air from Colorado and the Amazon rainforest. Results indicate that organics are important for both nucleation and growth, vapor uptake was limited to accumulation-mode particles, fragmentation reactions were important to limit particle growth at higher OH exposures, and an H2SO4-organics nucleation mechanism captured new particle formation well.
Hongyu Guo, Rene Otjes, Patrick Schlag, Astrid Kiendler-Scharr, Athanasios Nenes, and Rodney J. Weber
Atmos. Chem. Phys., 18, 12241–12256,Short summary
Reduction in ammonia has been proposed as a way to lower fine particle mass and improve air quality, but gas-phase ammonia is linked to agricultural productivity. We assess the feasibility of ammonia control at a variety of locations through an aerosol thermodynamic analysis. We show that aerosol response to ammonia control is highly nonlinear and only becomes effective when ambient particle pH drops below approximately 3. Particle pH is a relevant aerosol air quality parameter.
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,Short summary
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,Short summary
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.
Theodora Nah, Hongyu Guo, Amy P. Sullivan, Yunle Chen, David J. Tanner, Athanasios Nenes, Armistead Russell, Nga Lee Ng, L. Gregory Huey, and Rodney J. Weber
Atmos. Chem. Phys., 18, 11471–11491,Short summary
We present measurements from a field study conducted in an agriculturally intensive region in the southeastern US during the fall of 2016 to investigate how NH3 affects particle acidity and SOA formation via gas–particle partitioning of semi-volatile organic acids. For this study, higher NH3 concentrations relative to what has been measured in the region in previous studies had minor effects on PM1 organic acids and their influence on the overall organic aerosol and PM1 mass concentrations.
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,Short summary
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,Short summary
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.
Eliane G. Alves, Julio Tóta, Andrew Turnipseed, Alex B. Guenther, José Oscar W. Vega Bustillos, Raoni A. Santana, Glauber G. Cirino, Julia V. Tavares, Aline P. Lopes, Bruce W. Nelson, Rodrigo A. de Souza, Dasa Gu, Trissevgeni Stavrakou, David K. Adams, Jin Wu, Scott Saleska, and Antonio O. Manzi
Biogeosciences, 15, 4019–4032,Short summary
This study shows that leaf quantity and leaf age have an important effect on seasonal changes in isoprene emissions and that these could play an even more important role in regulating ecosystem isoprene fluxes than light and temperature at seasonal timescales in tropical forests. These results bring novelty and new insight for future research because in the past leaf phenology was not considered as an important factor that controls biological processes in the tropics.
Chunxiang Ye, Xianliang Zhou, Dennis Pu, Jochen Stutz, James Festa, Max Spolaor, Catalina Tsai, Christopher Cantrell, Roy L. Mauldin III, Andrew Weinheimer, Rebecca S. Hornbrook, Eric C. Apel, Alex Guenther, Lisa Kaser, Bin Yuan, Thomas Karl, Julie Haggerty, Samuel Hall, Kirk Ullmann, James Smith, and John Ortega
Atmos. Chem. Phys., 18, 9107–9120,Short summary
Substantial levels of HONO existed during the day throughout the troposphere over the southeastern US during NOMADSS 2013. Particulate nitrate photolysis appeared to be the major volume HONO source, while NOx was an important HONO precursor only in industrial and urban plumes. HONO was not a significant OH radical precursor in the rural troposphere away from the ground surface; however, its production from particulate nitrate photolysis was an important renoxification pathway.
Jens-Uwe Grooß, Rolf Müller, Reinhold Spang, Ines Tritscher, Tobias Wegner, Martyn P. Chipperfield, Wuhu Feng, Douglas E. Kinnison, and Sasha Madronich
Atmos. Chem. Phys., 18, 8647–8666,Short summary
We investigate a discrepancy between model simulations and observations of HCl in the dark polar stratosphere. In early winter, the less-well-studied period of the onset of chlorine activation, observations show a much faster depletion of HCl than simulations of three models. This points to some unknown process that is currently not represented in the models. Various hypotheses for potential causes are investigated that partly reduce the discrepancy. The impact on polar ozone depletion is low.
Maite Bauwens, Trissevgeni Stavrakou, Jean-François Müller, Bert Van Schaeybroeck, Lesley De Cruz, Rozemien De Troch, Olivier Giot, Rafiq Hamdi, Piet Termonia, Quentin Laffineur, Crist Amelynck, Niels Schoon, Bernard Heinesch, Thomas Holst, Almut Arneth, Reinhart Ceulemans, Arturo Sanchez-Lorenzo, and Alex Guenther
Biogeosciences, 15, 3673–3690,Short summary
Biogenic isoprene fluxes are simulated over Europe with the MEGAN–MOHYCAN model for the recent past and end-of-century climate at high spatiotemporal resolution (0.1°, 3 min). Due to climate change, fluxes increased by 40 % over 1979–2014. Climate scenarios for 2070–2099 suggest an increase by 83 % due to climate, and an even stronger increase when the potential impact of CO2 fertilization is considered (up to 141 %). Accounting for CO2 inhibition cancels out a large part of these increases.
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,Short summary
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,Short summary
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.
Nan Li, Qingyang He, Jim Greenberg, Alex Guenther, Jingyi Li, Junji Cao, Jun Wang, Hong Liao, Qiyuan Wang, and Qiang Zhang
Atmos. Chem. Phys., 18, 7489–7507,Short summary
O3 pollution has been increasing in most Chinese cities in recent years. Our study reveals that the synergistic impact of individual source contributions to O3 formation should be considered in the formation of air pollution control strategies, especially for big cities in the vicinity of forests.
Xi Chen, Mingjie Xie, Michael D. Hays, Eric Edgerton, Donna Schwede, and John T. Walker
Atmos. Chem. Phys., 18, 6829–6846,
Eunha Kang, Meehye Lee, William H. Brune, Taehyoung Lee, Taehyun Park, Joonyoung Ahn, and Xiaona Shang
Atmos. Chem. Phys., 18, 6661–6677,Short summary
A potential aerosol mass (PAM) reactor expedites slow atmospheric oxidation reactions and enables the observation of chemical aging processes and the determination of the aerosol-forming power of an air mass. A PAM reactor was deployed at Baengnyeong Island in the Yellow Sea. Experimental results confirm the key role of SO2 in generating secondary aerosols in northeast Asia, and the contribution of organics to secondary aerosols is more variable during transport in the atmosphere.
Evangelia Kostenidou, Eleni Karnezi, James R. Hite Jr., Aikaterini Bougiatioti, Kate Cerully, Lu Xu, Nga L. Ng, Athanasios Nenes, and Spyros N. Pandis
Atmos. Chem. Phys., 18, 5799–5819,Short summary
The volatility distribution of organic aerosol (OA) and its sources during the Southern Oxidant and Aerosol Study (SOAS) was estimated. The volatility distribution of all components covered a wide range including both semi-volatile and low-volatility components. The oxygen content of the factors can be combined with their estimated volatility and hygroscopicity to provide a better view of their physical properties.
Haiyan Li, Qiang Zhang, Bo Zheng, Chunrong Chen, Nana Wu, Hongyu Guo, Yuxuan Zhang, Yixuan Zheng, Xin Li, and Kebin He
Atmos. Chem. Phys., 18, 5293–5306,Short summary
This study revealed the driving role of nitrate in urban haze development in the North China Plain (NCP) during summertime. Several factors favoring the rapid nitrate formation were investigated in detail. The higher concentration and, in particular, the higher contribution of nitrate in PM1 suggest an urgent need to initiate ammonia emission control measures and further reduce NOx emissions over the NCP region.
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,Short summary
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,Short summary
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.
Julia Schmale, Silvia Henning, Stefano Decesari, Bas Henzing, Helmi Keskinen, Karine Sellegri, Jurgita Ovadnevaite, Mira L. Pöhlker, Joel Brito, Aikaterini Bougiatioti, Adam Kristensson, Nikos Kalivitis, Iasonas Stavroulas, Samara Carbone, Anne Jefferson, Minsu Park, Patrick Schlag, Yoko Iwamoto, Pasi Aalto, Mikko Äijälä, Nicolas Bukowiecki, Mikael Ehn, Göran Frank, Roman Fröhlich, Arnoud Frumau, Erik Herrmann, Hartmut Herrmann, Rupert Holzinger, Gerard Kos, Markku Kulmala, Nikolaos Mihalopoulos, Athanasios Nenes, Colin O'Dowd, Tuukka Petäjä, David Picard, Christopher Pöhlker, Ulrich Pöschl, Laurent Poulain, André Stephan Henry Prévôt, Erik Swietlicki, Meinrat O. Andreae, Paulo Artaxo, Alfred Wiedensohler, John Ogren, Atsushi Matsuki, Seong Soo Yum, Frank Stratmann, Urs Baltensperger, and Martin Gysel
Atmos. Chem. Phys., 18, 2853–2881,Short summary
Collocated long-term observations of cloud condensation nuclei (CCN) number concentrations, particle number size distributions and chemical composition from 12 sites are synthesized. Observations cover coastal environments, the Arctic, the Mediterranean, the boreal and rain forest, high alpine and continental background sites, and Monsoon-influenced areas. We interpret regional and seasonal variability. CCN concentrations are predicted with the κ–Köhler model and compared to the measurements.
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,Short summary
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,Short summary
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.
Kenneth E. Christian, William H. Brune, Jingqiu Mao, and Xinrong Ren
Atmos. Chem. Phys., 18, 2443–2460,Short summary
We applied a global sensitivity analysis to the GEOS-Chem chemical transport model analyzing some well-studied tropospheric oxidants for a time period corresponding to an aircraft field campaign. We find modeled results generally agree with measurements when uncertainties in both the model and measurements are taken into account. While model results were largely sensitive to emissions, chemical reaction rates also represented a large source of uncertainty.
Nina Sarnela, Tuija Jokinen, Jonathan Duplissy, Chao Yan, Tuomo Nieminen, Mikael Ehn, Siegfried Schobesberger, Martin Heinritzi, Sebastian Ehrhart, Katrianne Lehtipalo, Jasmin Tröstl, Mario Simon, Andreas Kürten, Markus Leiminger, Michael J. Lawler, Matti P. Rissanen, Federico Bianchi, Arnaud P. Praplan, Jani Hakala, Antonio Amorim, Marc Gonin, Armin Hansel, Jasper Kirkby, Josef Dommen, Joachim Curtius, James N. Smith, Tuukka Petäjä, Douglas R. Worsnop, Markku Kulmala, Neil M. Donahue, and Mikko Sipilä
Atmos. Chem. Phys., 18, 2363–2380,Short summary
Atmospheric trace gases can form small molecular clusters, which can grow to larger sizes through the condensation of vapours. This process is called new particle formation. In this paper we studied the formation of sulfuric acid and highly oxygenated molecules, the key compounds in atmospheric new particle formation, in chamber experiments and introduced a way to simulate these ozonolysis products of α-pinene in a simple manner.
Claire F. Fortenberry, Michael J. Walker, Yaping Zhang, Dhruv Mitroo, William H. Brune, and Brent J. Williams
Atmos. Chem. Phys., 18, 2199–2224,Short summary
In these laboratory studies, two types of biomass burning organic aerosol (BBOA) were generated in a combustion chamber and treated in a flow reactor to mimic atmospheric oxidation. Complementary bulk and molecular chemical measurements show that while many species deplete with oxidation, oxidized BBOA markers are enhanced. The results provide insight into the complex chemical evolution of BBOA over nearly 10 days of atmospheric photochemistry, informing future laboratory and field studies.
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,Short summary
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.
Sylvia C. Sullivan, Corinna Hoose, Alexei Kiselev, Thomas Leisner, and Athanasios Nenes
Atmos. Chem. Phys., 18, 1593–1610,Short summary
Ice multiplication (IM) processes can have a profound impact on cloud and precipitation development but are poorly understood. Here we study whether a lower limit of ice nuclei exists to initiate IM. The lower limit is found to be extremely low (0.01 per liter or less). A counterintuitive but profound conclusion thus emerges: IM requires cloud formation around a thermodynamic
sweet spotand is sensitive to fluctuations in cloud condensation nuclei concentration alone.
Lukas Pichelstorfer, Dominik Stolzenburg, John Ortega, Thomas Karl, Harri Kokkola, Anton Laakso, Kari E. J. Lehtinen, James N. Smith, Peter H. McMurry, and Paul M. Winkler
Atmos. Chem. Phys., 18, 1307–1323,Short summary
Quantification of new particle formation as a source of atmospheric aerosol is clearly of importance for climate and health aspects. In our new study we developed two analysis methods that allow retrieval of nanoparticle growth dynamics at much higher precision than it was possible so far. Our results clearly demonstrate that growth rates show much more variation than is currently known and suggest that the Kelvin effect governs growth in the sub-10 nm size range.
Xuan Wang, Colette L. Heald, Jiumeng Liu, Rodney J. Weber, Pedro Campuzano-Jost, Jose L. Jimenez, Joshua P. Schwarz, and Anne E. Perring
Atmos. Chem. Phys., 18, 635–653,Short summary
Brown carbon (BrC) contributes significantly to uncertainty in estimating the global direct radiative effect (DRE) of aerosols. We develop a global model simulation of BrC and test it against BrC absorption measurements from two aircraft campaigns in the continental United States. We suggest that BrC DRE has been overestimated previously due to the lack of observational constraints from direct measurements and omission of the effects of photochemical whitening.
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,Short summary
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,Short summary
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.
Haihan Chen, Anna L. Hodshire, John Ortega, James Greenberg, Peter H. McMurry, Annmarie G. Carlton, Jeffrey R. Pierce, Dave R. Hanson, and James N. Smith
Atmos. Chem. Phys., 18, 311–326,Short summary
Much of what we know about atmospheric new particle formation (NPF) is based on ground-level measurements. We used tethered balloon measurements and remote sensing to study the location in the boundary layer in which NPF events are initiated, the degree to which the boundary layer is well-mixed during NPF, and the potential role that water may play in aerosol particle chemical evolution. This information will improve the representativeness of process level models and laboratory experiments.
Robert Wagner, Chao Yan, Katrianne Lehtipalo, Jonathan Duplissy, Tuomo Nieminen, Juha Kangasluoma, Lauri R. Ahonen, Lubna Dada, Jenni Kontkanen, Hanna E. Manninen, Antonio Dias, Antonio Amorim, Paulus S. Bauer, Anton Bergen, Anne-Kathrin Bernhammer, Federico Bianchi, Sophia Brilke, Stephany Buenrostro Mazon, Xuemeng Chen, Danielle C. Draper, Lukas Fischer, Carla Frege, Claudia Fuchs, Olga Garmash, Hamish Gordon, Jani Hakala, Liine Heikkinen, Martin Heinritzi, Victoria Hofbauer, Christopher R. Hoyle, Jasper Kirkby, Andreas Kürten, Alexander N. Kvashnin, Tiia Laurila, Michael J. Lawler, Huajun Mai, Vladimir Makhmutov, Roy L. Mauldin III, Ugo Molteni, Leonid Nichman, Wei Nie, Andrea Ojdanic, Antti Onnela, Felix Piel, Lauriane L. J. Quéléver, Matti P. Rissanen, Nina Sarnela, Simon Schallhart, Kamalika Sengupta, Mario Simon, Dominik Stolzenburg, Yuri Stozhkov, Jasmin Tröstl, Yrjö Viisanen, Alexander L. Vogel, Andrea C. Wagner, Mao Xiao, Penglin Ye, Urs Baltensperger, Joachim Curtius, Neil M. Donahue, Richard C. Flagan, Martin Gallagher, Armin Hansel, James N. Smith, António Tomé, Paul M. Winkler, Douglas Worsnop, Mikael Ehn, Mikko Sipilä, Veli-Matti Kerminen, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 17, 15181–15197,
Demetrios Pagonis, Jordan E. Krechmer, Joost de Gouw, Jose L. Jimenez, and Paul J. Ziemann
Atmos. Meas. Tech., 10, 4687–4696,Short summary
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,Short summary
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.
Hendrik Fuchs, Anna Novelli, Michael Rolletter, Andreas Hofzumahaus, Eva Y. Pfannerstill, Stephan Kessel, Achim Edtbauer, Jonathan Williams, Vincent Michoud, Sebastien Dusanter, Nadine Locoge, Nora Zannoni, Valerie Gros, Francois Truong, Roland Sarda-Esteve, Danny R. Cryer, Charlotte A. Brumby, Lisa K. Whalley, Daniel Stone, Paul W. Seakins, Dwayne E. Heard, Coralie Schoemaecker, Marion Blocquet, Sebastien Coudert, Sebastien Batut, Christa Fittschen, Alexander B. Thames, William H. Brune, Cheryl Ernest, Hartwig Harder, Jennifer B. A. Muller, Thomas Elste, Dagmar Kubistin, Stefanie Andres, Birger Bohn, Thorsten Hohaus, Frank Holland, Xin Li, Franz Rohrer, Astrid Kiendler-Scharr, Ralf Tillmann, Robert Wegener, Zhujun Yu, Qi Zou, and Andreas Wahner
Atmos. Meas. Tech., 10, 4023–4053,Short summary
Hydroxyl radical reactivity (k(OH)) is closely related to processes that lead to the formation of oxidised, secondary pollutants such as ozone and aerosol. In order to compare the performances of instruments measuring k(OH), experiments were conducted in the simulation chamber SAPHIR. Chemical conditions were chosen either to be representative of the atmosphere or to test potential limitations of instruments. Overall, the results show that instruments are capable of measuring k(OH).
Bianca C. Baier, William H. Brune, David O. Miller, Donald Blake, Russell Long, Armin Wisthaler, Christopher Cantrell, Alan Fried, Brian Heikes, Steven Brown, Erin McDuffie, Frank Flocke, Eric Apel, Lisa Kaser, and Andrew Weinheimer
Atmos. Chem. Phys., 17, 11273–11292,Short summary
Ozone production rates were measured using the Measurement of Ozone Production Sensor (MOPS). Measurements are compared to modeled ozone production rates using two different chemical mechanisms. At high nitric oxide levels, observed rates are higher than those modeled, prompting the need to revisit current model photochemistry. These direct measurements can add to our understanding of the ozone chemistry within air quality models and can be used to guide government regulatory strategies.
Min Huang, Gregory R. Carmichael, James H. Crawford, Armin Wisthaler, Xiwu Zhan, Christopher R. Hain, Pius Lee, and Alex B. Guenther
Geosci. Model Dev., 10, 3085–3104,Short summary
Various sensitivity simulations during two airborne campaigns were performed to assess the impact of different initialization methods and model resolutions on NUWRF-modeled weather states, heat fluxes, and the follow-on MEGAN isoprene emission calculations. Proper land initialization is shown to be important to the coupled weather modeling and the follow-on emission modeling, which is also critical to accurately representing other processes in air quality modeling and data assimilation.
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,Short summary
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.
Dong Gao, Ting Fang, Vishal Verma, Linghan Zeng, and Rodney J. Weber
Atmos. Meas. Tech., 10, 2821–2835,Short summary
This work compares three methods to determine the optimal approach for quantifying the total oxidative potential (OP) of fine particles collected with filters using the dithiothreitol (DTT) assay. An automated system has been developed to facilitate the total OP measurements for use in generation of large data sets needed for epidemiology studies. The results from this study show that the water-insoluble components contribute to PM2.5 OP and the related DTT-active species are largely secondary.
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,Short summary
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,Short summary
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.
Khairunnisa Yahya, Timothy Glotfelty, Kai Wang, Yang Zhang, and Athanasios Nenes
Geosci. Model Dev., 10, 2333–2363,
Andrew Lambe, Paola Massoli, Xuan Zhang, Manjula Canagaratna, John Nowak, Conner Daube, Chao Yan, Wei Nie, Timothy Onasch, John Jayne, Charles Kolb, Paul Davidovits, Douglas Worsnop, and William Brune
Atmos. Meas. Tech., 10, 2283–2298,Short summary
This work enables the study of NOx-influenced secondary organic aerosol formation chemistry in oxidation flow reactors to an extent that was not previously possible. The method uses reactions of exited oxygen O(1D) radicals (formed from ozone photolysis at 254 nm or nitrous oxide photolysis at 185 nm) with nitrous oxide (N2O) to produce NO. We demonstrate proof of concept using chemical ionization mass spectrometer measurements to detect gas-phase oxidation products of isoprene and
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,
Petros Vasilakos, Yong-Ηa Kim, Jeffrey R. Pierce, Sotira Yiacoumi, Costas Tsouris, and Athanasios Nenes
Geosci. Model Dev. Discuss.,
Revised manuscript not acceptedShort summary
Radioactive charging can significantly impact the way radioactive aerosols behave, and as a result their lifetime, but such effects are neglected in predictive model studies of radioactive plumes. We extend a well-established model that simulates the evolution of atmospheric particulate matter to account for radioactive charging effects in an accurate and computationally efficient way. It is shown that radioactivity can strongly impact the deposition patterns of aerosol.
Hongyu Guo, Jiumeng Liu, Karl D. Froyd, James M. Roberts, Patrick R. Veres, Patrick L. Hayes, Jose L. Jimenez, Athanasios Nenes, and Rodney J. Weber
Atmos. Chem. Phys., 17, 5703–5719,Short summary
Fine particle pH is linked to many environmental impacts by affecting particle concentration and composition. Predicted Pasadena, CA (CalNex campaign), PM1 pH is 1.9 and PM2.5 pH 2.7, the latter higher due to sea salts. The model predicted gas–particle partitionings of HNO3–NO3−, NH3–NH4+, and HCl–Cl− are in good agreement, verifying the model predictions. A summary of contrasting locations in the US and eastern Mediterranean shows fine particles are generally highly acidic, with pH below 3.
Vlassis A. Karydis, Alexandra P. Tsimpidi, Sara Bacer, Andrea Pozzer, Athanasios Nenes, and Jos Lelieveld
Atmos. Chem. Phys., 17, 5601–5621,Short summary
The importance of mineral dust for cloud droplet formation is studied by considering the adsorption activation of insoluble dust particles and the thermodynamic interactions between mineral cations and inorganic anions. This study demonstrates that a comprehensive treatment of the CCN activity of mineral dust and its chemical and thermodynamic interactions with inorganic species by chemistry climate models is important to realistically account for aerosol–chemistry–cloud–climate interaction.
Hilkka Timonen, Panu Karjalainen, Erkka Saukko, Sanna Saarikoski, Päivi Aakko-Saksa, Pauli Simonen, Timo Murtonen, Miikka Dal Maso, Heino Kuuluvainen, Matthew Bloss, Erik Ahlberg, Birgitta Svenningsson, Joakim Pagels, William H. Brune, Jorma Keskinen, Douglas R. Worsnop, Risto Hillamo, and Topi Rönkkö
Atmos. Chem. Phys., 17, 5311–5329,Short summary
The effect of fuel ethanol content (10–100 %) on primary emissions and the subsequent secondary aerosol formation was investigated for a Euro 5 flex-fuel gasoline vehicle. The emissions were characterized during the New European Driving Cycle (NEDC) using high time-resolution instruments. The chemical composition of the exhaust particulate matter was studied using a soot particle aerosol mass spectrometer (SP-AMS), and the secondary aerosol formation was studied with an oxidation chamber.
Chandan Sarangi, Sachchida Nand Tripathi, Vijay P. Kanawade, Ilan Koren, and D. Sivanand Pai
Atmos. Chem. Phys., 17, 5185–5204,Short summary
Aerosol-induced perturbations in cloud systems and rainfall are very uncertain. This study provides observational evidence of a robust positive association between aerosol–cloud–rainfall properties over the Indian summer monsoon region. Observed and modeled aerosol–cloud microphysical changes illustrate that cloud invigoration under a high AOD scenario can explain most of the aerosol-associated changes in cloud fraction, cloud top pressure, and surface rainfall over this region.
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,Short summary
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.
Satoshi Takahama and Giulia Ruggeri
Atmos. Chem. Phys., 17, 4433–4450,Short summary
We formalize a method for classifying carbon atoms in organic aerosols according to their functionalization. This conceptual approach allows estimation of carbon mass from functional group measurements, which previously required a series of assumptions that were not well constrained. We describe how the proposed strategy can lead to better comparisons among functional group measurements, chemically explicit model simulations, and other measurements.
Kenneth E. Christian, William H. Brune, and Jingqiu Mao
Atmos. Chem. Phys., 17, 3769–3784,Short summary
To better understand the sources of uncertainty in modeled Arctic tropospheric oxidants, we created and analyzed an ensemble of chemical transport model runs with inputs perturbed according to their respective uncertainties. Ozone and OH were most sensitive to various emissions and chemical factors. HO2 was overwhelmingly sensitive to aerosol particle uptake. When compared to airborne measurements, better agreement was found when the model used lower aerosol particle uptake rates.
Jenni Kontkanen, Katrianne Lehtipalo, Lauri Ahonen, Juha Kangasluoma, Hanna E. Manninen, Jani Hakala, Clémence Rose, Karine Sellegri, Shan Xiao, Lin Wang, Ximeng Qi, Wei Nie, Aijun Ding, Huan Yu, Shanhu Lee, Veli-Matti Kerminen, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 17, 2163–2187,Short summary
The concentrations of ~1–3 nm particles were investigated at nine sites around the world. Sub-3 nm particle concentrations were highest at the sites with strong anthropogenic influence. Electrically neutral particles dominated sub-3 nm particle concentrations in polluted environments and in boreal forest during spring and summer. Sub-3 nm particle concentrations were observed to be determined by the availability of precursor vapors rather than the sink caused by preexisting aerosol particles.
Jiaoyan Huang, Matthieu B. Miller, Eric Edgerton, and Mae Sexauer Gustin
Atmos. Chem. Phys., 17, 1689–1698,Short summary
The highest mercury (Hg) wet deposition in USA occurs along the Gulf of Mexico. Gaseous oxidized Hg (GOM) is a major contributor due to high water solubility and reactivity. Concentration and dry deposition of GOM were determined for OLF, Florida. Results indicated at least 5 GOM compounds in this area including HgBr2, HgO, and Hg–nitrogen and –sulfur forms. GOM chemistry indicates reactions with local mobile source pollutants and long-range transport from outside of the USA.
Anusha P. S. Hettiyadura, Thilina Jayarathne, Karsten Baumann, Allen H. Goldstein, Joost A. de Gouw, Abigail Koss, Frank N. Keutsch, Kate Skog, and Elizabeth A. Stone
Atmos. Chem. Phys., 17, 1343–1359,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.
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,Short summary
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.
Wing Y. Tuet, Yunle Chen, Lu Xu, Shierly Fok, Dong Gao, Rodney J. Weber, and Nga L. Ng
Atmos. Chem. Phys., 17, 839–853,Short summary
Secondary organic aerosols (SOA) comprise a significant fraction of particulate matter (PM) and may have health implications. The water-soluble oxidative potentials of various SOA systems were determined using dithiothreitol consumption. Results from this study demonstrate that precursor identity was more influential than reaction condition in determining SOA oxidative potential and highlight a need to consider SOA contributions from anthropogenic hydrocarbons to PM-induced health effects.
Alexandra Tsekeri, Vassilis Amiridis, Franco Marenco, Athanasios Nenes, Eleni Marinou, Stavros Solomos, Phil Rosenberg, Jamie Trembath, Graeme J. Nott, James Allan, Michael Le Breton, Asan Bacak, Hugh Coe, Carl Percival, and Nikolaos Mihalopoulos
Atmos. Meas. Tech., 10, 83–107,Short summary
The In situ/Remote sensing aerosol Retrieval Algorithm (IRRA) provides vertical profiles of aerosol optical, microphysical and hygroscopic properties from airborne in situ and remote sensing measurements. The algorithm is highly advantageous for aerosol characterization in humid conditions, employing the ISORROPIA II model for acquiring the particle hygroscopic growth. IRRA can find valuable applications in aerosol–cloud interaction schemes and in validation of active space-borne sensors.
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,Short summary
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.
Panayiotis Kalkavouras, Elissavet Bossioli, Spiros Bezantakos, Aikaterini Bougiatioti, Nikos Kalivitis, Iasonas Stavroulas, Giorgos Kouvarakis, Anna P. Protonotariou, Aggeliki Dandou, George Biskos, Nikolaos Mihalopoulos, Athanasios Nenes, and Maria Tombrou
Atmos. Chem. Phys., 17, 175–192,Short summary
Concentrations of chemically and size-resolved submicron aerosol particles along with concentrations of gases and meteorological variables were measured at Santorini and Finokalia (central and southern Aegean Sea) during the Etesians. Particle nucleation bursts were recorded. The NPF can double CCN number (at 0.1 % supersaturation), but the resulting strong competition for water vapor in cloudy updrafts decreases maximum supersaturation by 14 % and augments the potential droplet number by 12 %.
Kerneels Jaars, Pieter G. van Zyl, Johan P. Beukes, Heidi Hellén, Ville Vakkari, Micky Josipovic, Andrew D. Venter, Matti Räsänen, Leandra Knoetze, Dirk P. Cilliers, Stefan J. Siebert, Markku Kulmala, Janne Rinne, Alex Guenther, Lauri Laakso, and Hannele Hakola
Atmos. Chem. Phys., 16, 15665–15688,Short summary
Biogenic volatile organic compounds (BVOCs) – important in tropospheric ozone and secondary organic aerosol formation – were measured at a savannah grassland in South Africa. Results presented are the most extensive for this type of landscape. Compared to other parts of the world, monoterpene levels were similar, while very low isoprene levels led to significantly lower total BVOC levels. BVOC levels were an order of magnitude lower compared to anthropogenic VOC levels measured at Welgegund.
Stelios Myriokefalitakis, Athanasios Nenes, Alex R. Baker, Nikolaos Mihalopoulos, and Maria Kanakidou
Biogeosciences, 13, 6519–6543,Short summary
The global atmospheric cycle of P is simulated accounting for natural and anthropogenic sources, acid dissolution of dust aerosol and changes in atmospheric acidity. Simulations show that P-containing dust dissolution flux may have increased in the last 150 years but is expected to decrease in the future, and biological particles are important carriers of bioavailable P to the ocean. These insights to the P cycle have important implications for marine ecosystem responses to climate change.
Yaping Zhang, Brent J. Williams, Allen H. Goldstein, Kenneth S. Docherty, and Jose L. Jimenez
Atmos. Meas. Tech., 9, 5637–5653,Short summary
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,Short summary
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).
Michael J. Lawler, Paul M. Winkler, Jaeseok Kim, Lars Ahlm, Jasmin Tröstl, Arnaud P. Praplan, Siegfried Schobesberger, Andreas Kürten, Jasper Kirkby, Federico Bianchi, Jonathan Duplissy, Armin Hansel, Tuija Jokinen, Helmi Keskinen, Katrianne Lehtipalo, Markus Leiminger, Tuukka Petäjä, Matti Rissanen, Linda Rondo, Mario Simon, Mikko Sipilä, Christina Williamson, Daniela Wimmer, Ilona Riipinen, Annele Virtanen, and James N. Smith
Atmos. Chem. Phys., 16, 13601–13618,Short summary
We present chemical observations of newly formed particles as small as ~ 10 nm from new particle formation experiments using sulfuric acid, dimethylamine, ammonia, and water vapor as gas phase reactants. The nanoparticles were more acidic than expected based on thermodynamic expectations, particularly at the smallest measured sizes. The results suggest rapid surface conversion of SO2 to sulfate and show a marked composition change between 10 and 15 nm, possibly indicating a phase change.
Amelia F. Longo, David J. Vine, Laura E. King, Michelle Oakes, Rodney J. Weber, Lewis Gregory Huey, Armistead G. Russell, and Ellery D. Ingall
Atmos. Chem. Phys., 16, 13389–13398,Short summary
New synchrotron-based techniques were applied to characterize the oxidation state and composition of sulfur in ambient aerosol and emission sources. Individual particles were found to contain surprisingly high levels of elemental sulfur, a form of sulfur found in only one of the emission sources analyzed. We also show metal sulfates as a key component of urban aerosols. These metal sulfate phases are highly soluble and are indicative of acidic processes transforming metals in the environment.
Ivan Kourtchev, Ricardo H. M. Godoi, Sarah Connors, James G. Levine, Alex T. Archibald, Ana F. L. Godoi, Sarah L. Paralovo, Cybelli G. G. Barbosa, Rodrigo A. F. Souza, Antonio O. Manzi, Roger Seco, Steve Sjostedt, Jeong-Hoo Park, Alex Guenther, Saewung Kim, James Smith, Scot T. Martin, and Markus Kalberer
Atmos. Chem. Phys., 16, 11899–11913,
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,Short summary
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.
Maite Bauwens, Trissevgeni Stavrakou, Jean-François Müller, Isabelle De Smedt, Michel Van Roozendael, Guido R. van der Werf, Christine Wiedinmyer, Johannes W. Kaiser, Katerina Sindelarova, and Alex Guenther
Atmos. Chem. Phys., 16, 10133–10158,Short summary
Relying on a 9-year record of satellite observations of formaldehyde, we use inverse techniques to derive global top–down hydrocarbon fluxes over 2005–2013, infer seasonal and interannual variability, and detect emission trends. Our results suggest changes in fire seasonal patterns, a stronger contribution of agricultural burning, overestimated isoprene flux rates in the tropics, overly decreased isoprene emissions due to soil moisture stress in arid areas, and enhanced isoprene trends.
Amit Misra, Vijay P. Kanawade, and Sachchida Nand Tripathi
Ann. Geophys., 34, 657–671,Short summary
For an accurate understanding of earth climate system, it is necessary to evaluate the performance of the climate models used to perform these simulations. In this work we have examined aerosol optical depths simulated by 17 models by comparing them with satellite-derived aerosol optical depth. Our results indicate the role of dust aerosols and biogeochemistry in the simulation of aerosols by models.
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,Short summary
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.
Rob L. Modini and Satoshi Takahama
Atmos. Meas. Tech., 9, 3337–3354,Short summary
Aerosol measurement techniques with high detection limits often result in poorly time-resolved measurements. We investigated sampling strategies and post-processing methods for constructing hourly resolved aerosol concentration time series from samples collected for 4 to 8 h. We show that this is an effective way to increase measurement time resolution, and that under realistic experimental conditions, simple methods can perform as well as more sophisticated methods.
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,Short summary
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.
Satoshi Takahama, Giulia Ruggeri, and Ann M. Dillner
Atmos. Meas. Tech., 9, 3429–3454,Short summary
We introduce the application of statistical algorithms that allow us to associate various dimensions of aerosol composition to vibrational modes measured by infrared absorption spectroscopy. We demonstrate their use on four organic functional groups for which absorption bands are known and extend the application to interpret bands associated with ambient organic carbon and elemental carbon quantified by an independent measurement technique that is widely used in aerosol monitoring networks.
Anna L. Hodshire, Michael J. Lawler, Jun Zhao, John Ortega, Coty Jen, Taina Yli-Juuti, Jared F. Brewer, Jack K. Kodros, Kelley C. Barsanti, Dave R. Hanson, Peter H. McMurry, James N. Smith, and Jeffery R. Pierce
Atmos. Chem. Phys., 16, 9321–9348,Short summary
Processes that control the growth of newly formed particles are not well understood and limit predictions of aerosol climate impacts. We combine state-of-the-art measurements at a central-US site with a particle-growth model to investigate the species and processes contributing to growth. Observed growth was dominated by organics, sulfate salts, or a mixture of these two. The model qualitatively captures the variability between different days.
Albert Rivas-Ubach, Yina Liu, Jordi Sardans, Malak M. Tfaily, Young-Mo Kim, Eric Bourrianne, Ljiljana Paša-Tolić, Josep Peñuelas, and Alex Guenther
Atmos. Meas. Tech. Discuss.,
Revised manuscript not accepted
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,Short summary
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.
Giulia Ruggeri, Fabian A. Bernhard, Barron H. Henderson, and Satoshi Takahama
Atmos. Chem. Phys., 16, 8729–8747,Short summary
Functional groups provide an intermediate level of chemical resolution between full molecular speciation and elemental composition for describing complex mixtures and can be a useful metric in model–measurement comparison of reaction kinetics and secondary organic aerosol formation. We introduce tools to facilitate such comparisons and demonstrate its application in study of the photooxidation of two precursor volatile organic compounds and the gas–particle partitioning of their products.
Panu Karjalainen, Hilkka Timonen, Erkka Saukko, Heino Kuuluvainen, Sanna Saarikoski, Päivi Aakko-Saksa, Timo Murtonen, Matthew Bloss, Miikka Dal Maso, Pauli Simonen, Erik Ahlberg, Birgitta Svenningsson, William Henry Brune, Risto Hillamo, Jorma Keskinen, and Topi Rönkkö
Atmos. Chem. Phys., 16, 8559–8570,Short summary
We characterized time-resolved primary particulate emissions and secondary particle formation from a modern gasoline passenger car. In mass terms, the amount of secondary particles was 13 times the amount of primary particles. The highest emissions were observed after a cold start when the engine and catalyst performance were suboptimal. The key parameter for secondary particle formation was the amount of gaseous hydrocarbons in the exhaust.
Abigail R. Koss, Carsten Warneke, Bin Yuan, Matthew M. Coggon, Patrick R. Veres, and Joost A. de Gouw
Atmos. Meas. Tech., 9, 2909–2925,Short summary
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.
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,Short summary
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.
Alma Hodzic, Prasad S. Kasibhatla, Duseong S. Jo, Christopher D. Cappa, Jose L. Jimenez, Sasha Madronich, and Rokjin J. Park
Atmos. Chem. Phys., 16, 7917–7941,Short summary
The global budget and spatial distribution of secondary organic aerosol (SOA) are highly uncertain in chemistry-climate models, which reflects our inability to characterize all phases of the OA lifecycle. We have performed global model simulations with the newly proposed formation and removal processes (photolysis and heterogeneous chemistry) and shown that SOA is a far more dynamic system, with 4 times stronger production rates and more efficient removal mechanisms, than assumed in models.
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,
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,Short summary
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.
Adele Kuzmiakova, Ann M. Dillner, and Satoshi Takahama
Atmos. Meas. Tech., 9, 2615–2631,Short summary
We describe a new method for removing Teflon substrate interference from ambient aerosol infrared spectra such that functional group quantification and spectral clustering (for source classification) can be applied. We demonstrate that this technique produces similar results to a more labor-intensive method used in many field campaigns over the past several years, but is simpler and better constrained by physical criteria that we impose, leading to the possibility of widespread adoption.
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,Short summary
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.
Aikaterini Bougiatioti, Spiros Bezantakos, Iasonas Stavroulas, Nikos Kalivitis, Panagiotis Kokkalis, George Biskos, Nikolaos Mihalopoulos, Alexandros Papayannis, and Athanasios Nenes
Atmos. Chem. Phys., 16, 7389–7409,Short summary
BBOA from long-range transport exhibits increased CCN concentrations for particles larger than 100 nm. At the same time the hygroscopicity parameter decreased for all particle sizes, as sub-100 nm particles appear to be richer in less hygroscopic organic material, while larger particles become less hygroscopic due to condensation of less hygroscopic gaseous compounds. Finally, atmospheric processing of freshly emitted BBOA to more oxidized organic aerosol can result in a 2-fold increase of κ.
Swen Metzger, Benedikt Steil, Mohamed Abdelkader, Klaus Klingmüller, Li Xu, Joyce E. Penner, Christos Fountoukis, Athanasios Nenes, and Jos Lelieveld
Atmos. Chem. Phys., 16, 7213–7237,Short summary
We introduce an unique single parameter framework to efficiently parameterize the aerosol water uptake for mixtures of semi-volatile and non-volatile compounds, being entirely based on the single solute specific coefficient introduced in Metzger et al. (2012).
Kathryn M. Emmerson, Ian E. Galbally, Alex B. Guenther, Clare Paton-Walsh, Elise-Andree Guerette, Martin E. Cope, Melita D. Keywood, Sarah J. Lawson, Suzie B. Molloy, Erin Dunne, Marcus Thatcher, Thomas Karl, and Simin D. Maleknia
Atmos. Chem. Phys., 16, 6997–7011,Short summary
We have tested how a model using a global inventory of plant-based emissions compares with four sets of measurements made in southeast Australia. This region is known for its eucalypt species, which dominate the summertime global inventory. The Australian part of the inventory has been produced using measurements made on eucalypt saplings. The model could not match the measurements, and the inventory needs to be improved by taking measurements of a wider range of Australian plant types and ages.
Chun Zhao, Maoyi Huang, Jerome D. Fast, Larry K. Berg, Yun Qian, Alex Guenther, Dasa Gu, Manish Shrivastava, Ying Liu, Stacy Walters, Gabriele Pfister, Jiming Jin, John E. Shilling, and Carsten Warneke
Geosci. Model Dev., 9, 1959–1976,Short summary
In this study, the latest version of MEGAN is coupled within CLM4 in WRF-Chem. In this implementation, MEGAN shares a consistent vegetation map with CLM4. This improved modeling framework is used to investigate the impact of two land surface schemes on BVOCs and examine the sensitivity of BVOCs to vegetation distributions in California. This study indicates that more effort is needed to obtain the most appropriate and accurate land cover data sets for climate and air quality models.
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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.
Aikaterini Bougiatioti, Panayiota Nikolaou, Iasonas Stavroulas, Giorgos Kouvarakis, Rodney Weber, Athanasios Nenes, Maria Kanakidou, and Nikolaos Mihalopoulos
Atmos. Chem. Phys., 16, 4579–4591,Short summary
Atmospheric aerosols and relevant parameters were measured in the eastern Mediterranean during summer and fall 2012. Submicron aerosol water can contribute up to 33 % of total mass, and 27.5 % of this can be associated with organics. Using these data, the pH of the submicron aerosols was calculated to be highly acidic, varying from 0.5 to 2.8 and independently of air masses origin. Such pH values could increase nutrient availability and thus sea water productivity of the Mediterranean Sea.
Giulia Ruggeri and Satoshi Takahama
Atmos. Chem. Phys., 16, 4401–4422,Short summary
We present a set of tools for mapping molecular information to functional group composition. This allows us to reduce the complexity of representing the organic aerosol composition, as it consists of hundreds of thousands of different compounds. We describe the tools and methods for validation, and demonstrate several applications in which this tool can facilitate measurement intercomparisons and chemical modeling of aerosol chemistry.
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,Short summary
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.
Zhe Peng, Douglas A. Day, Amber M. Ortega, Brett B. Palm, Weiwei Hu, Harald Stark, Rui Li, Kostas Tsigaridis, William H. Brune, and Jose L. Jimenez
Atmos. Chem. Phys., 16, 4283–4305,Short summary
Oxidation flow reactors (OFRs) are promising tools of studying atmospheric oxidation processes. Elevated concentrations of both OH and non-OH oxidants in OFRs leave room for speculation that non-OH chemistry can play a major role. Through systematic modeling, we find conditions where non-OH VOC fate is significant and show that, in most field studies of SOA using OFRs, non-OH VOC fate in OFRs was insignificant. We also provide guidelines helping OFR users avoid significant non-OH VOC oxidation.
Christopher R. Hoyle, Clare S. Webster, Harald E. Rieder, Athanasios Nenes, Emanuel Hammer, Erik Herrmann, Martin Gysel, Nicolas Bukowiecki, Ernest Weingartner, Martin Steinbacher, and Urs Baltensperger
Atmos. Chem. Phys., 16, 4043–4061,Short summary
A simple statistical model to predict the number of aerosols which activate to form cloud droplets in warm clouds has been established, based on regression analysis of data from the high-altitude site Jungfraujoch. It is found that cloud droplet formation at the Jungfraujoch is predominantly controlled by the number concentration of aerosol particles. A statistical model based on only the number of particles larger than 80nm can explain 79 % of the observed variance in droplet numbers.
Eliane G. Alves, Kolby Jardine, Julio Tota, Angela Jardine, Ana Maria Yãnez-Serrano, Thomas Karl, Julia Tavares, Bruce Nelson, Dasa Gu, Trissevgeni Stavrakou, Scot Martin, Paulo Artaxo, Antonio Manzi, and Alex Guenther
Atmos. Chem. Phys., 16, 3903–3925,Short summary
For a long time, it was thought that tropical rainforests are evergreen forests and the processes involved in these ecosystems do not change all year long. However, some satellite retrievals have suggested that ecophysiological processes may present seasonal variations mainly due to variation in light and leaf phenology in Amazonia. These in situ measurements are the first showing of a seasonal trend of volatile organic compound emissions, correlating with light and leaf phenology in Amazonia.
Ting Fang, Vishal Verma, Josephine T. Bates, Joseph Abrams, Mitchel Klein, Matthew J. Strickland, Stefanie E. Sarnat, Howard H. Chang, James A. Mulholland, Paige E. Tolbert, Armistead G. Russell, and Rodney J. Weber
Atmos. Chem. Phys., 16, 3865–3879,Short summary
Ascorbic acid (AA) and Dithiothreitol (DTT) assay measures of water-soluble PM2.5 oxidative potential (OP) are compared in terms of spatiotemporal trends, chemical selectivity, sources, and health impacts based on an epidemiological study with backcast estimated OP. Both assays point to metals from brake/tire wear, but only the DTT assay also identifies organics from combustion. DTT is associated with emergency department visits for asthma/wheeze and congestive heart failure, whereas AA is not.
Sean Coburn, Barbara Dix, Eric Edgerton, Christopher D. Holmes, Douglas Kinnison, Qing Liang, Arnout ter Schure, Siyuan Wang, and Rainer Volkamer
Atmos. Chem. Phys., 16, 3743–3760,Short summary
Here we present a day of case study measurements of the vertical distribution of bromine monoxide over the coastal region of the Gulf of Mexico. These measurements are used to assess the contribution of bromine radicals to the oxidation of elemental mercury in the troposphere. We find that the measured levels of bromine in the troposphere are sufficient to quickly oxidize mercury, which has significant implications for our understanding of atmospheric mercury processes.
Yong-ha Kim, Sotira Yiacoumi, Athanasios Nenes, and Costas Tsouris
Atmos. Chem. Phys., 16, 3449–3462,Short summary
Three microphysical approaches are proposed to incorporate mutual effects of particle charging and coagulation in predictions of transient charge and size distributions of atmospheric particles, including radioactive aerosols. The three approaches have different levels of complexities and are applicable to various laboratory and field atmospheric studies. Also, these approaches can be easily incorporated into aerosol transport models at different scales to account for particle charging effects.
Brett B. Palm, Pedro Campuzano-Jost, Amber M. Ortega, Douglas A. Day, Lisa Kaser, Werner Jud, Thomas Karl, Armin Hansel, James F. Hunter, Eben S. Cross, Jesse H. Kroll, Zhe Peng, William H. Brune, and Jose L. Jimenez
Atmos. Chem. Phys., 16, 2943–2970,Short summary
Ambient pine forest air was oxidized by OH radicals in a PAM oxidation flow reactor during the BEACHON-RoMBAS campaign to study secondary organic aerosol formation. Approximately 4.4 times more secondary organic aerosol was formed in the reactor than could be explained by the volatile organic gases (VOCs) measured in ambient air. The organic aerosol formation can be explained by including an SOA yield from typically unmeasured semivolatile and intermediate-volatility organic gases (S/IVOCs).
Sylvia C. Sullivan, Ricardo Morales Betancourt, Donifan Barahona, and Athanasios Nenes
Atmos. Chem. Phys., 16, 2611–2629,Short summary
We use the adjoint model of a cirrus parameterization to quantify sources of crystal variability for various ice-nucleating spectra and output from CAM5. The sensitivities can be directly linked to nucleation regime and efficiency of various INP. The lab-based spectrum calculates much higher INP efficiencies than field-based ones, owing to aerosol surface properties. The sensitivity to temperature tends to be low, due to the compensating effects of temperature on INP spectrum parameters.
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,Short summary
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,Short summary
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.
Haijie Tong, Andrea M. Arangio, Pascale S. J. Lakey, Thomas Berkemeier, Fobang Liu, Christopher J. Kampf, William H. Brune, Ulrich Pöschl, and Manabu Shiraiwa
Atmos. Chem. Phys., 16, 1761–1771,Short summary
We provide experimental evidence that terpene and isoprene SOA form substantial amounts of OH radicals upon interaction with liquid water and iron. Our measurements and model results imply that the chemical reactivity of SOA in the atmosphere, particularly in clouds, can be faster than previously thought. Inhalation and deposition of SOA particles in the human respiratory tract may lead to a substantial release of OH radicals in vivo, causing oxidative stress and adverse aerosol health effects.
Matteo Reggente, Ann M. Dillner, and Satoshi Takahama
Atmos. Meas. Tech., 9, 441–454,Short summary
Organic carbon and elemental carbon are major components of atmospheric PM. Typically they are measured using destructive and relatively expensive methods (e.g., TOR). We aim to reduce the operating costs of large air quality monitoring networks using FT-IR spectra of ambient PTFE filters and PLS regression. We achieve accurate predictions for models (calibrated in 2011) that use samples collected at the same or different sites of the calibration data set and in a different year (2013).
Y. S. La, M. Camredon, P. J. Ziemann, R. Valorso, A. Matsunaga, V. Lannuque, J. Lee-Taylor, A. Hodzic, S. Madronich, and B. Aumont
Atmos. Chem. Phys., 16, 1417–1431,Short summary
The potential impact of chamber walls on the loss of gaseous organic species and secondary organic aerosol (SOA) formation has been explored using the GECKO-A modeling tool, which explicitly represents SOA formation and gas-wall partitioning. The model was compared with 41 smog chamber experiments of SOA formation under OH oxidation of alkane and alkene serie. The organic vapor loss to the chamber walls is found to affect SOA yields as well as the composition of the gas and the particle phase.
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,Short summary
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.
L. M. Zamora, R. A. Kahn, M. J. Cubison, G. S. Diskin, J. L. Jimenez, Y. Kondo, G. M. McFarquhar, A. Nenes, K. L. Thornhill, A. Wisthaler, A. Zelenyuk, and L. D. Ziemba
Atmos. Chem. Phys., 16, 715–738,Short summary
Based on extensive aircraft campaigns, we quantify how biomass burning smoke affects subarctic and Arctic liquid cloud microphysical properties. Enhanced cloud albedo may decrease short-wave radiative flux by between 2 and 4 Wm2 or more in some subarctic conditions. Smoke halved average cloud droplet diameter. In one case study, it also appeared to limit droplet formation. Numerous Arctic background Aitken particles can also interact with combustion particles, perhaps affecting their properties.
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,Short summary
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,Short summary
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. Kim, L. Ahlm, T. Yli-Juuti, M. Lawler, H. Keskinen, J. Tröstl, S. Schobesberger, J. Duplissy, A. Amorim, F. Bianchi, N. M. Donahue, R. C. Flagan, J. Hakala, M. Heinritzi, T. Jokinen, A. Kürten, A. Laaksonen, K. Lehtipalo, P. Miettinen, T. Petäjä, M. P. Rissanen, L. Rondo, K. Sengupta, M. Simon, A. Tomé, C. Williamson, D. Wimmer, P. M. Winkler, S. Ehrhart, P. Ye, J. Kirkby, J. Curtius, U. Baltensperger, M. Kulmala, K. E. J. Lehtinen, J. N. Smith, I. Riipinen, and A. Virtanen
Atmos. Chem. Phys., 16, 293–304,Short summary
The hygroscopicity of nucleated nanoparticles was measured in the presence of sulfuric acid, sulfuric acid-dimethylamine, and sulfuric acid-organics derived from α-pinene oxidation during CLOUD7 at CERN in 2012. The hygroscopicity parameter κ decreased with increasing particle size, indicating decreasing acidity of particles.
F. Yu, G. Luo, S. C. Pryor, P. R. Pillai, S. H. Lee, J. Ortega, J. J. Schwab, A. G. Hallar, W. R. Leaitch, V. P. Aneja, J. N. Smith, J. T. Walker, O. Hogrefe, and K. L. Demerjian
Atmos. Chem. Phys., 15, 13993–14003,Short summary
The role of low-volatility organics in new particle formation (NPF) in the atmosphere is assessed. An empirical formulation in which formation rate is a function of the concentrations of sulfuric acid and low-volatility organics significantly overpredicts NPF in the summer. Two different schemes predict quite different nucleation rates (including their spatial patterns), concentrations of cloud condensation nuclei, and aerosol first indirect radiative forcing in North America.
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,Short summary
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,
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,Short summary
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,Short summary
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.
Z. Peng, D. A. Day, H. Stark, R. Li, J. Lee-Taylor, B. B. Palm, W. H. Brune, and J. L. Jimenez
Atmos. Meas. Tech., 8, 4863–4890,
R. Gonzalez-Abraham, S. H. Chung, J. Avise, B. Lamb, E. P. Salathé Jr., C. G. Nolte, D. Loughlin, A. Guenther, C. Wiedinmyer, T. Duhl, Y. Zhang, and D. G. Streets
Atmos. Chem. Phys., 15, 12645–12665,
M. Paramonov, V.-M. Kerminen, M. Gysel, P. P. Aalto, M. O. Andreae, E. Asmi, U. Baltensperger, A. Bougiatioti, D. Brus, G. P. Frank, N. Good, S. S. Gunthe, L. Hao, M. Irwin, A. Jaatinen, Z. Jurányi, S. M. King, A. Kortelainen, A. Kristensson, H. Lihavainen, M. Kulmala, U. Lohmann, S. T. Martin, G. McFiggans, N. Mihalopoulos, A. Nenes, C. D. O'Dowd, J. Ovadnevaite, T. Petäjä, U. Pöschl, G. C. Roberts, D. Rose, B. Svenningsson, E. Swietlicki, E. Weingartner, J. Whitehead, A. Wiedensohler, C. Wittbom, and B. Sierau
Atmos. Chem. Phys., 15, 12211–12229,Short summary
The research paper presents the first comprehensive overview of field measurements with the CCN Counter performed at a large number of locations around the world within the EUCAARI framework. The paper sheds light on the CCN number concentrations and activated fractions around the world and their dependence on the water vapour supersaturation ratio, the dependence of aerosol hygroscopicity on particle size, and seasonal and diurnal variation of CCN activation and hygroscopic properties.
A. Guha, D. R. Gentner, R. J. Weber, R. Provencal, and A. H. Goldstein
Atmos. Chem. Phys., 15, 12043–12063,Short summary
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.
T. Stavrakou, J.-F. Müller, M. Bauwens, I. De Smedt, M. Van Roozendael, M. De Mazière, C. Vigouroux, F. Hendrick, M. George, C. Clerbaux, P.-F. Coheur, and A. Guenther
Atmos. Chem. Phys., 15, 11861–11884,Short summary
Formaldehyde columns from two space sensors, GOME-2 and OMI, constrain by inverse modeling the global emissions of HCHO precursors in 2010. The resulting biogenic and pyrogenic fluxes from both optimizations show a very good degree of consistency. The isoprene fluxes are reduced globally by ca. 10%, and emissions from fires decrease by ca. 35%, compared to the prior. Anthropogenic emissions are weakly constrained except over China. Sensitivity inversions show robustness of the inferred fluxes.
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,Short summary
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.
T. Fang, H. Guo, V. Verma, R. E. Peltier, and R. J. Weber
Atmos. Chem. Phys., 15, 11667–11682,Short summary
This work presented a new method of quantifying water-soluble elements in PM2.5 aqueous extracts (N~500) with an X-ray fluorescence analyzer. The results indicate that water-soluble elements had marked spatial and temporal patterns. Four sources were resolved: brake/tire wear, biomass burning, secondary formation, and mineral dust. The findings have informed studies on aerosol oxidative potential and provided insights into the health effects of water-soluble metals, especially Cu, Fe, Mn and Zn.
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,Short summary
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,Short summary
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.
A. M. Dillner and S. Takahama
Atmos. Meas. Tech., 8, 4013–4023,Short summary
Elemental carbon (EC), a constituent of atmospheric particulate matter (PM), adversely affects climate, visibility and human health. EC is measured in PM monitoring networks world-wide but the method is expensive and destructive to the samples. Here, methods are presented to accurately predict EC using Fourier transform infrared (FT-IR) analysis which is inexpensive and non-destructive. This method complements measurements of organic carbon and organic functional groups made using FT-IR.
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,Short summary
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,Short summary
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.
N. Kalivitis, V.-M. Kerminen, G. Kouvarakis, I. Stavroulas, A. Bougiatioti, A. Nenes, H. E. Manninen, T. Petäjä, M. Kulmala, and N. Mihalopoulos
Atmos. Chem. Phys., 15, 9203–9215,Short summary
Cloud condensation nuclei (CCN) production associated with atmospheric new particle formation (NPF) is presented, and this is the first direct evidence of CCN production resulting from NPF in the eastern Mediterranean atmosphere. We show that condensation of both gaseous sulfuric acid and organic compounds from multiple sources leads to the rapid growth of nucleated particles. Sub-100nm particles were found to be substantially less hygroscopic than larger particles during the active NPF period.
A. Hodzic, S. Madronich, P. S. Kasibhatla, G. Tyndall, B. Aumont, J. L. Jimenez, J. Lee-Taylor, and J. Orlando
Atmos. Chem. Phys., 15, 9253–9269,Short summary
Our study combines process and global chemistry modeling to investigate the potential effect of gas- and particle-phase organic photolysis reactions on the formation and lifetime of secondary organic aerosols (SOAs). Photolysis of the oxidation intermediates that partition between gas and particle phases to form SOA is not included in 3D models. Our results suggest that exposure to UV light can suppress the formation of SOA or even lead to its substantial loss (comparable to wet deposition).
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,Short summary
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.
K. M. Cerully, A. Bougiatioti, J. R. Hite Jr., H. Guo, L. Xu, N. L. Ng, R. Weber, and A. Nenes
Atmos. Chem. Phys., 15, 8679–8694,Short summary
The hygroscopicity of SE US aerosol is mostly water-soluble, with a hygroscopicity that is insensitive to partial volatilization in a thermodenuder. The most and least oxidized components of the aerosol are the most hygroscopic of organic constituents. No clear relationship was found between organic aerosol hygroscopicity and oxygen-to-carbon ratio. The aerosol factors covary in a way that induces the observed diurnal invariance in total organic hygroscopicity.
L. Zhou, R. Gierens, A. Sogachev, D. Mogensen, J. Ortega, J. N. Smith, P. C. Harley, A. J. Prenni, E. J. T. Levin, A. Turnipseed, A. Rusanen, S. Smolander, A. B. Guenther, M. Kulmala, T. Karl, and M. Boy
Atmos. Chem. Phys., 15, 8643–8656,
L. Hildebrandt Ruiz, A. L. Paciga, K. M. Cerully, A. Nenes, N. M. Donahue, and S. N. Pandis
Atmos. Chem. Phys., 15, 8301–8313,Short summary
Secondary organic aerosol (SOA) is transformed after its initial formation. We explored the effects of this chemical aging on the composition, mass yield, volatility, and hygroscopicity of SOA formed from the photo-oxidation of small aromatic volatile organic compounds. Higher exposure to the hydroxyl radical resulted in different SOA composition, average carbon oxidation state, and mass yield. The vapor pressure of SOA formed under different conditions varied by as much as a factor of 30.
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,Short summary
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. Liu, E. Scheuer, J. Dibb, G. S. Diskin, L. D. Ziemba, K. L. Thornhill, B. E. Anderson, A. Wisthaler, T. Mikoviny, J. J. Devi, M. Bergin, A. E. Perring, M. Z. Markovic, J. P. Schwarz, P. Campuzano-Jost, D. A. Day, J. L. Jimenez, and R. J. Weber
Atmos. Chem. Phys., 15, 7841–7858,Short summary
Brown carbon (BrC) is found throughout the US continental troposphere during a summer of extensive biomass burning and its prevalence relative to black carbon (BC) increases with altitude. A radiative transfer model based on direct measurements of aerosol scattering and absorption by BC and BrC shows BrC reduces top-of-atmosphere forcing by 20%. A method to estimate BrC radiative forcing efficiencies from surface-based measurements is provided.
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,
Y. Shinozuka, A. D. Clarke, A. Nenes, A. Jefferson, R. Wood, C. S. McNaughton, J. Ström, P. Tunved, J. Redemann, K. L. Thornhill, R. H. Moore, T. L. Lathem, J. J. Lin, and Y. J. Yoon
Atmos. Chem. Phys., 15, 7585–7604,
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,Short summary
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.
L. Xu, S. Suresh, H. Guo, R. J. Weber, and N. L. Ng
Atmos. Chem. Phys., 15, 7307–7336,Short summary
Year-long comprehensive characterization of ambient aerosol was performed in both rural and urban sites in the southeastern US as part of Southeastern Center of Air Pollution and Epidemiology (SCAPE) study and Southeastern Oxidant and Aerosol Study (SOAS). Three independent methods were applied to estimate the concentration of particle-phase organic nitrates. The spatial distribution of organic aerosol is investigated by comparing simultaneous HR-ToF-AMS and ACSM measurements at different sites.
S. Myriokefalitakis, N. Daskalakis, N. Mihalopoulos, A. R. Baker, A. Nenes, and M. Kanakidou
Biogeosciences, 12, 3973–3992,Short summary
The global atmospheric cycle of Fe is simulated accounting for natural and combustion sources, proton- and organic ligand-promoted Fe dissolution from dust aerosol and changes in anthropogenic emissions, and thus in atmospheric acidity. Simulations show that Fe dissolution may have increased in the last 150 years and is expected to decrease due to air pollution regulations. Reductions in dissolved-Fe deposition can further limit the primary productivity over high-nutrient-low-chlorophyll water.
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,Short summary
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,Short summary
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.
E. A. Bruns, I. El Haddad, A. Keller, F. Klein, N. K. Kumar, S. M. Pieber, J. C. Corbin, J. G. Slowik, W. H. Brune, U. Baltensperger, and A. S. H. Prévôt
Atmos. Meas. Tech., 8, 2315–2332,
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,Short summary
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.
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,Short summary
(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.
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,Short summary
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.
H. Guo, L. Xu, A. Bougiatioti, K. M. Cerully, S. L. Capps, J. R. Hite Jr., A. G. Carlton, S.-H. Lee, M. H. Bergin, N. L. Ng, A. Nenes, and R. J. Weber
Atmos. Chem. Phys., 15, 5211–5228,Short summary
Particle pH can affect many aerosol processes, including gas-particle partitioning, SOA formation, and mobilization of toxic redox metals. pH is challenging to directly measure and often improperly characterized by proxies like ion balances or molar ratios of measured aerosol ionic species. We present a detailed analysis predicting pH with a thermodynamic model, verify the prediction, and test pH sensitivity to model inputs based on data from the SOAS field campaign.
S. Kim, S.-Y. Kim, M. Lee, H. Shim, G. M. Wolfe, A. B. Guenther, A. He, Y. Hong, and J. Han
Atmos. Chem. Phys., 15, 4357–4371,
J. Huang, M. B. Miller, E. Edgerton, and M. S. Gustin
Atmos. Chem. Phys. Discuss.,
Revised manuscript not acceptedShort summary
Gaseous oxidized Hg (GOM) is a major contributor to Hg in wet and dry deposition. Recent work has indicated that the concentrations of GOM as measured are too low by 3-to-12 times; and that compounds vary across space and time. Data collected in Florida indicate five potential GOM compounds, including HgBr2, HgO, Hg(NO3)2, HgSO4, and an unknown compound. Sources include local combustion (cars and power plants), the marine boundary layer, and long range transport from Asia.
J. W. Taylor, J. D. Allan, D. Liu, M. Flynn, R. Weber, X. Zhang, B. L. Lefer, N. Grossberg, J. Flynn, and H. Coe
Atmos. Meas. Tech., 8, 1701–1718,Short summary
When using the SP2 to report black carbon core/shell coating thickness, the core density and refractive index must be estimated from literature values. We systematically vary the assumed parameters and the instrument calibration, and quantify the effects in the derived coatings. The technique is highly sensitive to the core refractive index but has only a minor sensitivity to the core density and coating refractive index. We identify the most appropriate values to use in future analysis.
A. T. Lambe, P. S. Chhabra, T. B. Onasch, W. H. Brune, J. F. Hunter, J. H. Kroll, M. J. Cummings, J. F. Brogan, Y. Parmar, D. R. Worsnop, C. E. Kolb, and P. Davidovits
Atmos. Chem. Phys., 15, 3063–3075,Short summary
We compared the chemistry and yields of SOA generated from OH oxidation of gas-phase precursors in a flow reactor (high OH, short residence time) and environmental chambers (low OH, long residence time). We find that chemical composition of SOA produced in the flow reactor and in chambers is similar. SOA yields measured in the flow reactor are lower than in chambers. Seed particles increase the yield of SOA produced in the flow reactor and may account in part for higher SOA yields in chambers.
C. J. Hennigan, J. Izumi, A. P. Sullivan, R. J. Weber, and A. Nenes
Atmos. Chem. Phys., 15, 2775–2790,Short summary
We show that the ion balance and molar ratio methods are unsuitable for use as aerosol pH proxies. Our recommendation is that 1) thermodynamic equilibrium models constrained by both gas and aerosol inputs run in the forward (open) mode, and 2) the phase partitioning of ammonia provides the best predictions of aerosol pH. Given the significance of acidity for numerous chemical processes in the atmosphere, the implications of this study are important and far reaching.
A. M. Dillner and S. Takahama
Atmos. Meas. Tech., 8, 1097–1109,Short summary
We demonstrate the feasibility of using FT-IR spectra of aerosols and a multivariate calibration to estimate organic carbon (OC) from thermal-optical reflectance analysis. Using 800 IMPROVE samples, we establish that prediction error can be explained by differences in distributions of OC and aerosol composition between calibration and test set. This work is an initial step in proposing a non-destructive analysis method that can reduce the operating costs of large air quality monitoring networks.
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,Short summary
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.
T. Fang, V. Verma, H. Guo, L. E. King, E. S. Edgerton, and R. J. Weber
Atmos. Meas. Tech., 8, 471–482,Short summary
This work summarizes a newly developed semi-automated system for quantifying the oxidative potential of aerosol aqueous extracts using the dithiothreitol (DTT) assay. 500 sample analyses indicate that DTT activity in the southeast US is likely not dominated by a unique local source, and sources change with season. The unique large data set generated with the technique described in this paper allows new studies on DTT sources and investigating linkages between reactive oxygen species and health.
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,
J. Lee-Taylor, A. Hodzic, S. Madronich, B. Aumont, M. Camredon, and R. Valorso
Atmos. Chem. Phys., 15, 595–615,
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,Short summary
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,
L. Q. Hao, A. Kortelainen, S. Romakkaniemi, H. Portin, A. Jaatinen, A. Leskinen, M. Komppula, P. Miettinen, D. Sueper, A. Pajunoja, J. N. Smith, K. E. J. Lehtinen, D. R. Worsnop, A. Laaksonen, and A. Virtanen
Atmos. Chem. Phys., 14, 13483–13495,Short summary
Positive matrix factorization (PMF) was applied to the unified high-resolution mass spectra organic species with NO+ and NO2+ ions from the measurement in a mixed region between the boreal forestland and the urban area. The PMF analysis succeeded in separating the mixed spectra into three distinct organic factors and one inorganic factor. The particulate organic nitrate was distinguished by PMF for the first time, with a contribution of one-third of the total nitrate mass.
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,Short summary
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,
V. Verma, T. Fang, H. Guo, L. King, J. T. Bates, R. E. Peltier, E. Edgerton, A. G. Russell, and R. J. Weber
Atmos. Chem. Phys., 14, 12915–12930,Short summary
The major emission sources of the reactive oxygen species (ROS) associated with ambient particulate matter in the southeastern United States were identified. The study shows biomass burning and secondary aerosol formation as the major sources contributing to the ROS-generating capability of ambient particles. The ubiquitous nature of these two sources suggests widespread population exposures to the toxic aerosol components.
L. Lee, P. J. Wooldridge, J. B. Gilman, C. Warneke, J. de Gouw, and R. C. Cohen
Atmos. Chem. Phys., 14, 12441–12454,Short summary
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.
C. S. Brauer, T. A. Blake, A. B. Guenther, S. W. Sharpe, R. L. Sams, and T. J. Johnson
Atmos. Meas. Tech., 7, 3839–3847,