Articles | Volume 25, issue 22
https://doi.org/10.5194/acp-25-15715-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-25-15715-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
17 Nov 2025
Research article |
| 17 Nov 2025
| 17 Nov 2025
Formation of highly oxygenated organic molecules from α-pinene photooxidation: evidence for the importance of highly oxygenated alkoxy radicals
Sungah Kang
Institute of Energy and Climate Systems, ICE-3, Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
Jürgen Wildt
Institute of Bio- and Geosciences, IBG-2, Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
retired
Iida Pullinen
Institute of Energy and Climate Systems, ICE-3, Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
present address: Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
Luc Vereecken
Institute of Energy and Climate Systems, ICE-3, Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
Institute of Energy and Climate Systems, ICE-3, Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
present address: Department of Chemistry and Molecular biology, University of Gothenburg, Göteborg, 41390, Sweden
Andreas Wahner
Institute of Energy and Climate Systems, ICE-3, Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
Institute of Energy and Climate Systems, ICE-3, Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
Thomas F. Mentel
Institute of Energy and Climate Systems, ICE-3, Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
retired
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Chemical mechanisms describe the chemical processes in atmospheric models that are used to describe the changes in the atmospheric composition. Therefore, accurate chemical mechanisms are necessary to predict the evolution of air pollution and climate change. The article describes all steps that are needed to build chemical mechanisms and discusses the advances and needs of experimental and theoretical research activities needed to build reliable chemical mechanisms.
Kuo-Ying Wang, Philippe Nedelec, Valerie Thouret, Hannah Clark, Andreas Wahner, and Andreas Petzold
EGUsphere, https://doi.org/10.5194/egusphere-2024-2414, https://doi.org/10.5194/egusphere-2024-2414, 2024
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We use routine in-service commercial passenger airplanes Airbus A340 and A330 to collect air pollutants in the upper troposphere. The beauty in using commercial airplanes is that these commercial airplanes, like taxi on the ground, keep flying all the time. We find that short-lived air pollutants are very sensitive to ground-level emissions. Effective regulation in ground-level emissions can help to reduce air pollution in the upper troposphere.
Yarê Baker, Sungah Kang, Hui Wang, Rongrong Wu, Jian Xu, Annika Zanders, Quanfu He, Thorsten Hohaus, Till Ziehm, Veronica Geretti, Thomas J. Bannan, Simon P. O'Meara, Aristeidis Voliotis, Mattias Hallquist, Gordon McFiggans, Sören R. Zorn, Andreas Wahner, and Thomas F. Mentel
Atmos. Chem. Phys., 24, 4789–4807, https://doi.org/10.5194/acp-24-4789-2024, https://doi.org/10.5194/acp-24-4789-2024, 2024
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Highly oxygenated organic molecules are important contributors to secondary organic aerosol. Their yield depends on detailed atmospheric chemical composition. One important parameter is the ratio of hydroperoxy radicals to organic peroxy radicals (HO2/RO2), and we show that higher HO2/RO2 ratios lower the secondary organic aerosol yield. This is of importance as laboratory studies are often biased towards organic peroxy radicals.
Rongrong Wu, Sören R. Zorn, Sungah Kang, Astrid Kiendler-Scharr, Andreas Wahner, and Thomas F. Mentel
Atmos. Meas. Tech., 17, 1811–1835, https://doi.org/10.5194/amt-17-1811-2024, https://doi.org/10.5194/amt-17-1811-2024, 2024
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Recent advances in high-resolution time-of-flight chemical ionization mass spectrometry (CIMS) enable the detection of highly oxygenated organic molecules, which efficiently contribute to secondary organic aerosol. Here we present an application of fuzzy c-means (FCM) clustering to deconvolve CIMS data. FCM not only reduces the complexity of mass spectrometric data but also the chemical and kinetic information retrieved by clustering gives insights into the chemical processes involved.
Wei Huang, Cheng Wu, Linyu Gao, Yvette Gramlich, Sophie L. Haslett, Joel Thornton, Felipe D. Lopez-Hilfiker, Ben H. Lee, Junwei Song, Harald Saathoff, Xiaoli Shen, Ramakrishna Ramisetty, Sachchida N. Tripathi, Dilip Ganguly, Feng Jiang, Magdalena Vallon, Siegfried Schobesberger, Taina Yli-Juuti, and Claudia Mohr
Atmos. Chem. Phys., 24, 2607–2624, https://doi.org/10.5194/acp-24-2607-2024, https://doi.org/10.5194/acp-24-2607-2024, 2024
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We present distinct molecular composition and volatility of oxygenated organic aerosol particles in different rural, urban, and mountain environments. We do a comprehensive investigation of the relationship between the chemical composition and volatility of oxygenated organic aerosol particles across different systems and environments. This study provides implications for volatility descriptions of oxygenated organic aerosol particles in different model frameworks.
Ernst-Peter Röth and Luc Vereecken
Atmos. Chem. Phys., 24, 2625–2638, https://doi.org/10.5194/acp-24-2625-2024, https://doi.org/10.5194/acp-24-2625-2024, 2024
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The paper presents the radical and molecular product quantum yields in the photolysis reaction of CHDO at wavelengths above 300 nm. Two different approaches based on literature data are used, with results falling within both approaches' uncertainty ranges. Simple functional forms are presented for use in photochemical models of the atmosphere.
Jing Cai, Juha Sulo, Yifang Gu, Sebastian Holm, Runlong Cai, Steven Thomas, Almuth Neuberger, Fredrik Mattsson, Marco Paglione, Stefano Decesari, Matteo Rinaldi, Rujing Yin, Diego Aliaga, Wei Huang, Yuanyuan Li, Yvette Gramlich, Giancarlo Ciarelli, Lauriane Quéléver, Nina Sarnela, Katrianne Lehtipalo, Nora Zannoni, Cheng Wu, Wei Nie, Juha Kangasluoma, Claudia Mohr, Markku Kulmala, Qiaozhi Zha, Dominik Stolzenburg, and Federico Bianchi
Atmos. Chem. Phys., 24, 2423–2441, https://doi.org/10.5194/acp-24-2423-2024, https://doi.org/10.5194/acp-24-2423-2024, 2024
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By combining field measurements, simulations and recent chamber experiments, we investigate new particle formation (NPF) and growth in the Po Valley, where both haze and frequent NPF occur. Our results show that sulfuric acid, ammonia and amines are the dominant NPF precursors there. A high NPF rate and a lower condensation sink lead to a greater survival probability for newly formed particles, highlighting the importance of gas-to-particle conversion for aerosol concentrations.
Arto Heitto, Cheng Wu, Diego Aliaga, Luis Blacutt, Xuemeng Chen, Yvette Gramlich, Liine Heikkinen, Wei Huang, Radovan Krejci, Paolo Laj, Isabel Moreno, Karine Sellegri, Fernando Velarde, Kay Weinhold, Alfred Wiedensohler, Qiaozhi Zha, Federico Bianchi, Marcos Andrade, Kari E. J. Lehtinen, Claudia Mohr, and Taina Yli-Juuti
Atmos. Chem. Phys., 24, 1315–1328, https://doi.org/10.5194/acp-24-1315-2024, https://doi.org/10.5194/acp-24-1315-2024, 2024
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Particle growth at the Chacaltaya station in Bolivia was simulated based on measured vapor concentrations and ambient conditions. Major contributors to the simulated growth were low-volatility organic compounds (LVOCs). Also, sulfuric acid had major role when volcanic activity was occurring in the area. This study provides insight on nanoparticle growth at this high-altitude Southern Hemispheric site and hence contributes to building knowledge of early growth of atmospheric particles.
Jacky Y. S. Pang, Florian Berg, Anna Novelli, Birger Bohn, Michelle Färber, Philip T. M. Carlsson, René Dubus, Georgios I. Gkatzelis, Franz Rohrer, Sergej Wedel, Andreas Wahner, and Hendrik Fuchs
Atmos. Chem. Phys., 23, 12631–12649, https://doi.org/10.5194/acp-23-12631-2023, https://doi.org/10.5194/acp-23-12631-2023, 2023
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In this study, the oxidations of sabinene by OH radicals and ozone were investigated with an atmospheric simulation chamber. Reaction rate coefficients of the OH-oxidation reaction at temperatures between 284 to 340 K were determined for the first time in the laboratory by measuring the OH reactivity. Product yields determined in chamber experiments had good agreement with literature values, but discrepancies were found between experimental yields and expected yields from oxidation mechanisms.
Emelie L. Graham, Cheng Wu, David M. Bell, Amelie Bertrand, Sophie L. Haslett, Urs Baltensperger, Imad El Haddad, Radovan Krejci, Ilona Riipinen, and Claudia Mohr
Atmos. Chem. Phys., 23, 7347–7362, https://doi.org/10.5194/acp-23-7347-2023, https://doi.org/10.5194/acp-23-7347-2023, 2023
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The volatility of an aerosol particle is an important parameter for describing its atmospheric lifetime. We studied the volatility of secondary organic aerosols from nitrate-initiated oxidation of three biogenic precursors with experimental methods and model simulations. We saw higher volatility than for the corresponding ozone system, and our simulations produced variable results with different parameterizations which warrant a re-evaluation of the treatment of the nitrate functional group.
Hao Luo, Luc Vereecken, Hongru Shen, Sungah Kang, Iida Pullinen, Mattias Hallquist, Hendrik Fuchs, Andreas Wahner, Astrid Kiendler-Scharr, Thomas F. Mentel, and Defeng Zhao
Atmos. Chem. Phys., 23, 7297–7319, https://doi.org/10.5194/acp-23-7297-2023, https://doi.org/10.5194/acp-23-7297-2023, 2023
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Oxidation of limonene, an element emitted by trees and chemical products, by OH, a daytime oxidant, forms many highly oxygenated organic molecules (HOMs), including C10-20 compounds. HOMs play an important role in new particle formation and growth. HOM formation can be explained by the chemistry of peroxy radicals. We found that a minor branching ratio initial pathway plays an unexpected, significant role. Considering this pathway enables accurate simulations of HOMs and other concentrations.
Qiaozhi Zha, Wei Huang, Diego Aliaga, Otso Peräkylä, Liine Heikkinen, Alkuin Maximilian Koenig, Cheng Wu, Joonas Enroth, Yvette Gramlich, Jing Cai, Samara Carbone, Armin Hansel, Tuukka Petäjä, Markku Kulmala, Douglas Worsnop, Victoria Sinclair, Radovan Krejci, Marcos Andrade, Claudia Mohr, and Federico Bianchi
Atmos. Chem. Phys., 23, 4559–4576, https://doi.org/10.5194/acp-23-4559-2023, https://doi.org/10.5194/acp-23-4559-2023, 2023
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We investigate the chemical composition of atmospheric cluster ions from January to May 2018 at the high-altitude research station Chacaltaya (5240 m a.s.l.) in the Bolivian Andes. With state-of-the-art mass spectrometers and air mass history analysis, the measured cluster ions exhibited distinct diurnal and seasonal patterns, some of which contributed to new particle formation. Our study will improve the understanding of atmospheric ions and their role in high-altitude new particle formation.
Philip T. M. Carlsson, Luc Vereecken, Anna Novelli, François Bernard, Steven S. Brown, Bellamy Brownwood, Changmin Cho, John N. Crowley, Patrick Dewald, Peter M. Edwards, Nils Friedrich, Juliane L. Fry, Mattias Hallquist, Luisa Hantschke, Thorsten Hohaus, Sungah Kang, Jonathan Liebmann, Alfred W. Mayhew, Thomas Mentel, David Reimer, Franz Rohrer, Justin Shenolikar, Ralf Tillmann, Epameinondas Tsiligiannis, Rongrong Wu, Andreas Wahner, Astrid Kiendler-Scharr, and Hendrik Fuchs
Atmos. Chem. Phys., 23, 3147–3180, https://doi.org/10.5194/acp-23-3147-2023, https://doi.org/10.5194/acp-23-3147-2023, 2023
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The investigation of the night-time oxidation of the most abundant hydrocarbon, isoprene, in chamber experiments shows the importance of reaction pathways leading to epoxy products, which could enhance particle formation, that have so far not been accounted for. The chemical lifetime of organic nitrates from isoprene is long enough for the majority to be further oxidized the next day by daytime oxidants.
Jing Cai, Kaspar R. Daellenbach, Cheng Wu, Yan Zheng, Feixue Zheng, Wei Du, Sophie L. Haslett, Qi Chen, Markku Kulmala, and Claudia Mohr
Atmos. Meas. Tech., 16, 1147–1165, https://doi.org/10.5194/amt-16-1147-2023, https://doi.org/10.5194/amt-16-1147-2023, 2023
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We introduce the offline application of FIGAERO-CIMS by analyzing Teflon and quartz filter samples that were collected at a typical urban site in Beijing with the deposition time varying from 30 min to 24 h. This method provides a feasible, simple, and quantitative way to investigate the molecular composition and volatility of OA compounds by using FIGAERO-CIMS to analyze offline samples.
Changmin Cho, Hendrik Fuchs, Andreas Hofzumahaus, Frank Holland, William J. Bloss, Birger Bohn, Hans-Peter Dorn, Marvin Glowania, Thorsten Hohaus, Lu Liu, Paul S. Monks, Doreen Niether, Franz Rohrer, Roberto Sommariva, Zhaofeng Tan, Ralf Tillmann, Astrid Kiendler-Scharr, Andreas Wahner, and Anna Novelli
Atmos. Chem. Phys., 23, 2003–2033, https://doi.org/10.5194/acp-23-2003-2023, https://doi.org/10.5194/acp-23-2003-2023, 2023
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With this study, we investigated the processes leading to the formation, destruction, and recycling of radicals for four seasons in a rural environment. Complete knowledge of their chemistry is needed if we are to predict the formation of secondary pollutants from primary emissions. The results highlight a still incomplete understanding of the paths leading to the formation of the OH radical, which has been observed in several other environments as well and needs to be further investigated.
Wiebke Scholz, Jiali Shen, Diego Aliaga, Cheng Wu, Samara Carbone, Isabel Moreno, Qiaozhi Zha, Wei Huang, Liine Heikkinen, Jean Luc Jaffrezo, Gaelle Uzu, Eva Partoll, Markus Leiminger, Fernando Velarde, Paolo Laj, Patrick Ginot, Paolo Artaxo, Alfred Wiedensohler, Markku Kulmala, Claudia Mohr, Marcos Andrade, Victoria Sinclair, Federico Bianchi, and Armin Hansel
Atmos. Chem. Phys., 23, 895–920, https://doi.org/10.5194/acp-23-895-2023, https://doi.org/10.5194/acp-23-895-2023, 2023
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Dimethyl sulfide (DMS), emitted from the ocean, is the most abundant biogenic sulfur emission into the atmosphere. OH radicals, among others, can oxidize DMS to sulfuric and methanesulfonic acid, which are relevant for aerosol formation. We quantified DMS and nearly all DMS oxidation products with novel mass spectrometric instruments for gas and particle phase at the high mountain station Chacaltaya (5240 m a.s.l.) in the Bolivian Andes in free tropospheric air after long-range transport.
Zijun Li, Angela Buchholz, Luis M. F. Barreira, Arttu Ylisirniö, Liqing Hao, Iida Pullinen, Siegfried Schobesberger, and Annele Virtanen
Atmos. Chem. Phys., 23, 203–220, https://doi.org/10.5194/acp-23-203-2023, https://doi.org/10.5194/acp-23-203-2023, 2023
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Interaction between NOx and biogenic emissions can be important in suburban areas. Our study showed that the addition of NOx during α-pinene SOA formation produced considerable amounts of organic nitrates and affected the composition of non-nitrated organic compounds. The compositional difference consequently altered the primary type of aqueous-phase processes during the isothermal particle evaporation.
Aristeidis Voliotis, Mao Du, Yu Wang, Yunqi Shao, M. Rami Alfarra, Thomas J. Bannan, Dawei Hu, Kelly L. Pereira, Jaqueline F. Hamilton, Mattias Hallquist, Thomas F. Mentel, and Gordon McFiggans
Atmos. Chem. Phys., 22, 14147–14175, https://doi.org/10.5194/acp-22-14147-2022, https://doi.org/10.5194/acp-22-14147-2022, 2022
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Mixing experiments are crucial and highly beneficial for our understanding of atmospheric chemical interactions. However, interpretation quickly becomes complex, and both the experimental design and evaluation need to be scrutinised carefully. Advanced online and offline compositional measurements can reveal substantial additional information to aid in the interpretation of yield data, including components uniquely found in mixtures and property changes in SOA formed from mixtures of VOCs.
David M. Bell, Cheng Wu, Amelie Bertrand, Emelie Graham, Janne Schoonbaert, Stamatios Giannoukos, Urs Baltensperger, Andre S. H. Prevot, Ilona Riipinen, Imad El Haddad, and Claudia Mohr
Atmos. Chem. Phys., 22, 13167–13182, https://doi.org/10.5194/acp-22-13167-2022, https://doi.org/10.5194/acp-22-13167-2022, 2022
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A series of studies designed to investigate the evolution of organic aerosol were performed in an atmospheric simulation chamber, using a common oxidant found at night (NO3). The chemical composition steadily changed from its initial composition via different chemical reactions that were taking place inside of the aerosol particle. These results show that the composition of organic aerosol steadily changes during its lifetime in the atmosphere.
Zhaofeng Tan, Hendrik Fuchs, Andreas Hofzumahaus, William J. Bloss, Birger Bohn, Changmin Cho, Thorsten Hohaus, Frank Holland, Chandrakiran Lakshmisha, Lu Liu, Paul S. Monks, Anna Novelli, Doreen Niether, Franz Rohrer, Ralf Tillmann, Thalassa S. E. Valkenburg, Vaishali Vardhan, Astrid Kiendler-Scharr, Andreas Wahner, and Roberto Sommariva
Atmos. Chem. Phys., 22, 13137–13152, https://doi.org/10.5194/acp-22-13137-2022, https://doi.org/10.5194/acp-22-13137-2022, 2022
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During the 2019 JULIAC campaign, ClNO2 was measured at a rural site in Germany in different seasons. The highest ClNO2 level was 1.6 ppbv in September. ClNO2 production was more sensitive to the availability of NO2 than O3. The average ClNO2 production efficiency was up to 18 % in February and September and down to 3 % in December. These numbers are at the high end of the values reported in the literature, indicating the importance of ClNO2 chemistry in rural environments in midwestern Europe.
Silvia M. Calderón, Juha Tonttila, Angela Buchholz, Jorma Joutsensaari, Mika Komppula, Ari Leskinen, Liqing Hao, Dmitri Moisseev, Iida Pullinen, Petri Tiitta, Jian Xu, Annele Virtanen, Harri Kokkola, and Sami Romakkaniemi
Atmos. Chem. Phys., 22, 12417–12441, https://doi.org/10.5194/acp-22-12417-2022, https://doi.org/10.5194/acp-22-12417-2022, 2022
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The spatial and temporal restrictions of observations and oversimplified aerosol representation in large eddy simulations (LES) limit our understanding of aerosol–stratocumulus interactions. In this closure study of in situ and remote sensing observations and outputs from UCLALES–SALSA, we have assessed the role of convective overturning and aerosol effects in two cloud events observed at the Puijo SMEAR IV station, Finland, a diurnal-high aerosol case and a nocturnal-low aerosol case.
Yindong Guo, Hongru Shen, Iida Pullinen, Hao Luo, Sungah Kang, Luc Vereecken, Hendrik Fuchs, Mattias Hallquist, Ismail-Hakki Acir, Ralf Tillmann, Franz Rohrer, Jürgen Wildt, Astrid Kiendler-Scharr, Andreas Wahner, Defeng Zhao, and Thomas F. Mentel
Atmos. Chem. Phys., 22, 11323–11346, https://doi.org/10.5194/acp-22-11323-2022, https://doi.org/10.5194/acp-22-11323-2022, 2022
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The oxidation of limonene, a common volatile emitted by trees and chemical products, by NO3, a nighttime oxidant, forms many highly oxygenated organic molecules (HOM), including C10-30 compounds. Most of the HOM are second-generation organic nitrates, in which carbonyl-substituted C10 nitrates accounted for a major fraction. Their formation can be explained by chemistry of peroxy radicals. HOM, especially low-volatile ones, play an important role in nighttime new particle formation and growth.
Lisa J. Beck, Siegfried Schobesberger, Heikki Junninen, Janne Lampilahti, Antti Manninen, Lubna Dada, Katri Leino, Xu-Cheng He, Iida Pullinen, Lauriane L. J. Quéléver, Anna Franck, Pyry Poutanen, Daniela Wimmer, Frans Korhonen, Mikko Sipilä, Mikael Ehn, Douglas R. Worsnop, Veli-Matti Kerminen, Tuukka Petäjä, Markku Kulmala, and Jonathan Duplissy
Atmos. Chem. Phys., 22, 8547–8577, https://doi.org/10.5194/acp-22-8547-2022, https://doi.org/10.5194/acp-22-8547-2022, 2022
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The presented article introduces an overview of atmospheric ions and their composition above the boreal forest. We provide the results of an extensive airborne measurement campaign with an air ion mass spectrometer and particle measurements, showing their diurnal evolution within the boundary layer and free troposphere. In addition, we compare the airborne dataset with the co-located data from the ground at SMEAR II station, Finland.
Jacky Yat Sing Pang, Anna Novelli, Martin Kaminski, Ismail-Hakki Acir, Birger Bohn, Philip T. M. Carlsson, Changmin Cho, Hans-Peter Dorn, Andreas Hofzumahaus, Xin Li, Anna Lutz, Sascha Nehr, David Reimer, Franz Rohrer, Ralf Tillmann, Robert Wegener, Astrid Kiendler-Scharr, Andreas Wahner, and Hendrik Fuchs
Atmos. Chem. Phys., 22, 8497–8527, https://doi.org/10.5194/acp-22-8497-2022, https://doi.org/10.5194/acp-22-8497-2022, 2022
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This study investigates the radical chemical budget during the limonene oxidation at different atmospheric-relevant NO concentrations in chamber experiments under atmospheric conditions. It is found that the model–measurement discrepancies of HO2 and RO2 are very large at low NO concentrations that are typical for forested environments. Possible additional processes impacting HO2 and RO2 concentrations are discussed.
Mike J. Newland, Camille Mouchel-Vallon, Richard Valorso, Bernard Aumont, Luc Vereecken, Michael E. Jenkin, and Andrew R. Rickard
Atmos. Chem. Phys., 22, 6167–6195, https://doi.org/10.5194/acp-22-6167-2022, https://doi.org/10.5194/acp-22-6167-2022, 2022
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Alkene ozonolysis produces Criegee intermediates, which can act as oxidants or decompose to give a range of closed-shell and radical products, including OH. Therefore it is essential to accurately represent the chemistry of Criegee intermediates in atmospheric models in order to understand their impacts on atmospheric composition. Here we provide a mechanism construction protocol by which the central features of alkene ozonolysis chemistry can be included in an automatic mechanism generator.
Jing Cai, Cheng Wu, Jiandong Wang, Wei Du, Feixue Zheng, Simo Hakala, Xiaolong Fan, Biwu Chu, Lei Yao, Zemin Feng, Yongchun Liu, Yele Sun, Jun Zheng, Chao Yan, Federico Bianchi, Markku Kulmala, Claudia Mohr, and Kaspar R. Daellenbach
Atmos. Chem. Phys., 22, 1251–1269, https://doi.org/10.5194/acp-22-1251-2022, https://doi.org/10.5194/acp-22-1251-2022, 2022
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This study investigates the connection between organic aerosol (OA) molecular composition and particle absorptive properties in autumn in Beijing. We find that the molecular properties of OA compounds in different episodes influence particle light absorption properties differently: the light absorption enhancement of black carbon and light absorption coefficient of brown carbon were mostly related to more oxygenated OA (low C number and four O atoms) and aromatics/nitro-aromatics, respectively.
Noora Hyttinen, Iida Pullinen, Aki Nissinen, Siegfried Schobesberger, Annele Virtanen, and Taina Yli-Juuti
Atmos. Chem. Phys., 22, 1195–1208, https://doi.org/10.5194/acp-22-1195-2022, https://doi.org/10.5194/acp-22-1195-2022, 2022
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Accurate saturation vapor pressure estimates of atmospherically relevant organic compounds are critical for modeling secondary organic aerosol (SOA) formation. We investigated vapor pressures of highly oxygenated SOA constituents using state-of-the-art computational and experimental methods. We found a good agreement between low and extremely low vapor pressures estimated using the two methods, and the smallest molecules detected in our experiment were likely products of thermal decomposition.
Najin Kim, Yafang Cheng, Nan Ma, Mira L. Pöhlker, Thomas Klimach, Thomas F. Mentel, Ovid O. Krüger, Ulrich Pöschl, and Hang Su
Atmos. Meas. Tech., 14, 6991–7005, https://doi.org/10.5194/amt-14-6991-2021, https://doi.org/10.5194/amt-14-6991-2021, 2021
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A broad supersaturation scanning CCN (BS2-CCN) system, in which particles are exposed to a range of supersaturation simultaneously, can measure a broad range of CCN activity distribution with a high time resolution. We describe how the BS2-CCN system can be effectively calibrated and which factors can affect the calibration curve. Intercomparison experiments between typical DMA-CCN and BS2-CCN measurements to evaluate the BS2-CCN system showed high correlation and good agreement.
Zhaofeng Tan, Luisa Hantschke, Martin Kaminski, Ismail-Hakki Acir, Birger Bohn, Changmin Cho, Hans-Peter Dorn, Xin Li, Anna Novelli, Sascha Nehr, Franz Rohrer, Ralf Tillmann, Robert Wegener, Andreas Hofzumahaus, Astrid Kiendler-Scharr, Andreas Wahner, and Hendrik Fuchs
Atmos. Chem. Phys., 21, 16067–16091, https://doi.org/10.5194/acp-21-16067-2021, https://doi.org/10.5194/acp-21-16067-2021, 2021
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The photo-oxidation of myrcene, a monoterpene species emitted by plants, was investigated at atmospheric conditions in the outdoor simulation chamber SAPHIR. The chemical structure of myrcene is partly similar to isoprene. Therefore, it can be expected that hydrogen shift reactions could play a role as observed for isoprene. In this work, their potential impact on the regeneration efficiency of hydroxyl radicals is investigated.
Cheng Wu, David M. Bell, Emelie L. Graham, Sophie Haslett, Ilona Riipinen, Urs Baltensperger, Amelie Bertrand, Stamatios Giannoukos, Janne Schoonbaert, Imad El Haddad, Andre S. H. Prevot, Wei Huang, and Claudia Mohr
Atmos. Chem. Phys., 21, 14907–14925, https://doi.org/10.5194/acp-21-14907-2021, https://doi.org/10.5194/acp-21-14907-2021, 2021
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Night-time reactions of biogenic volatile organic compounds and nitrate radicals can lead to the formation of secondary organic aerosol (BSOANO3). Here, we study the impacts of light exposure on the BSOANO3 from three biogenic precursors. Our results suggest that photolysis causes photodegradation of a substantial fraction of BSOANO3, changes the chemical composition and bulk volatility, and might be a potentially important loss pathway of BSOANO3 during the night-to-day transition.
Philipp G. Eger, Luc Vereecken, Rolf Sander, Jan Schuladen, Nicolas Sobanski, Horst Fischer, Einar Karu, Jonathan Williams, Ville Vakkari, Tuukka Petäjä, Jos Lelieveld, Andrea Pozzer, and John N. Crowley
Atmos. Chem. Phys., 21, 14333–14349, https://doi.org/10.5194/acp-21-14333-2021, https://doi.org/10.5194/acp-21-14333-2021, 2021
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We determine the impact of pyruvic acid photolysis on the formation of acetaldehyde and peroxy radicals during summer and autumn in the Finnish boreal forest using a data-constrained box model. Our results are dependent on the chosen scenario in which the overall quantum yield and the photolysis products are varied. We highlight that pyruvic acid photolysis can be an important contributor to acetaldehyde and peroxy radical formation in remote, forested regions.
Luisa Hantschke, Anna Novelli, Birger Bohn, Changmin Cho, David Reimer, Franz Rohrer, Ralf Tillmann, Marvin Glowania, Andreas Hofzumahaus, Astrid Kiendler-Scharr, Andreas Wahner, and Hendrik Fuchs
Atmos. Chem. Phys., 21, 12665–12685, https://doi.org/10.5194/acp-21-12665-2021, https://doi.org/10.5194/acp-21-12665-2021, 2021
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The reactions of Δ3-carene with ozone and the hydroxyl radical (OH) and the photolysis and OH reaction of caronaldehyde were investigated in the simulation chamber SAPHIR. Reaction rate constants of these reactions were determined. Caronaldehyde yields of the ozonolysis and OH reaction were determined. The organic nitrate yield of the reaction of Δ3-carene and caronaldehyde-derived peroxy radicals with NO was determined. The ROx budget (ROx = OH+HO2+RO2) was also investigated.
Janne Lampilahti, Hanna E. Manninen, Tuomo Nieminen, Sander Mirme, Mikael Ehn, Iida Pullinen, Katri Leino, Siegfried Schobesberger, Juha Kangasluoma, Jenni Kontkanen, Emma Järvinen, Riikka Väänänen, Taina Yli-Juuti, Radovan Krejci, Katrianne Lehtipalo, Janne Levula, Aadu Mirme, Stefano Decesari, Ralf Tillmann, Douglas R. Worsnop, Franz Rohrer, Astrid Kiendler-Scharr, Tuukka Petäjä, Veli-Matti Kerminen, Thomas F. Mentel, and Markku Kulmala
Atmos. Chem. Phys., 21, 12649–12663, https://doi.org/10.5194/acp-21-12649-2021, https://doi.org/10.5194/acp-21-12649-2021, 2021
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We studied aerosol particle formation and growth in different parts of the planetary boundary layer at two different locations (Po Valley, Italy, and Hyytiälä, Finland). The observations consist of airborne measurements on board an instrumented Zeppelin and a small airplane combined with comprehensive ground-based measurements.
Cited articles
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Short summary
Highly oxygenated organic molecules by atmospheric oxidation of plant emitted monoterpenes are important components in secondary organic aerosol formation. Autoxidation of organic peroxy radicals is one important pathway of their formation. We show that isomerization of highly oxygenated alkoxy radicals leads to highly oxygenated peroxy radicals that continue the autoxidation chain. Alkoxy-peroxy steps may dominate the formation of highly oxygenated molecules at high nitrogen oxide levels.
Highly oxygenated organic molecules by atmospheric oxidation of plant emitted monoterpenes are...
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