Articles | Volume 14, issue 3
https://doi.org/10.5194/amt-14-1851-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-14-1851-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
05 Mar 2021
Research article |
| 05 Mar 2021
| 05 Mar 2021
Characterization of a chemical modulation reactor (CMR) for the measurement of atmospheric concentrations of hydroxyl radicals with a laser-induced fluorescence instrument
Changmin Cho
Troposphere (IEK-8), Institute of Energy and Climate Research, Forschungszentrum Jülich, 52425 Jülich, Germany
Andreas Hofzumahaus
CORRESPONDING AUTHOR
Troposphere (IEK-8), Institute of Energy and Climate Research, Forschungszentrum Jülich, 52425 Jülich, Germany
Hendrik Fuchs
Troposphere (IEK-8), Institute of Energy and Climate Research, Forschungszentrum Jülich, 52425 Jülich, Germany
Hans-Peter Dorn
Troposphere (IEK-8), Institute of Energy and Climate Research, Forschungszentrum Jülich, 52425 Jülich, Germany
Marvin Glowania
Troposphere (IEK-8), Institute of Energy and Climate Research, Forschungszentrum Jülich, 52425 Jülich, Germany
Frank Holland
Troposphere (IEK-8), Institute of Energy and Climate Research, Forschungszentrum Jülich, 52425 Jülich, Germany
Franz Rohrer
Troposphere (IEK-8), Institute of Energy and Climate Research, Forschungszentrum Jülich, 52425 Jülich, Germany
Vaishali Vardhan
Troposphere (IEK-8), Institute of Energy and Climate Research, Forschungszentrum Jülich, 52425 Jülich, Germany
Astrid Kiendler-Scharr
Troposphere (IEK-8), Institute of Energy and Climate Research, Forschungszentrum Jülich, 52425 Jülich, Germany
Andreas Wahner
Troposphere (IEK-8), Institute of Energy and Climate Research, Forschungszentrum Jülich, 52425 Jülich, Germany
Troposphere (IEK-8), Institute of Energy and Climate Research, Forschungszentrum Jülich, 52425 Jülich, Germany
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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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Amir H. Souri, Matthew S. Johnson, Glenn M. Wolfe, James H. Crawford, Alan Fried, Armin Wisthaler, William H. Brune, Donald R. Blake, Andrew J. Weinheimer, Tijl Verhoelst, Steven Compernolle, Gaia Pinardi, Corinne Vigouroux, Bavo Langerock, Sungyeon Choi, Lok Lamsal, Lei Zhu, Shuai Sun, Ronald C. Cohen, Kyung-Eun Min, Changmin Cho, Sajeev Philip, Xiong Liu, and Kelly Chance
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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
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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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Julianna Antonia Christopoulos, Pablo Saide, Manas Mohanty, Nattamon Maneenoi, Jhoon Kim, Laura Judd, Katherine Travis, Savitri Garivait, Agapol Junpen, Kazuyuki Miyazaki, Jinkyul Choi, Takashi Sekiya, David Peterson, Theodore McHardy, Nicholas Gapp, Jason St. Clair, Erin Delaria, Glenn Wolfe, Abby Sebol, Alessandro Franchin, Changmin Cho, Morgan Silverman, and James H. Crawford
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Air quality in rapidly growing cities is difficult to model because emissions vary throughout the day and are poorly constrained. We study Bangkok by combining hourly satellite observations with high-resolution air quality modeling to estimate nitrogen dioxide emissions. We find emissions are much lower than commonly used inventories, and that updated emissions improve model agreement with aircraft and ground observations.
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This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
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Alexandros Milousis, Susanne M. C. Scholz, Hendrik Fuchs, Alexandra P. Tsimpidi, and Vlassis A. Karydis
Atmos. Chem. Phys., 26, 571–605, https://doi.org/10.5194/acp-26-571-2026, https://doi.org/10.5194/acp-26-571-2026, 2026
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Nitrate aerosol has become a dominant atmospheric component, surpassing sulfate in aerosol composition. However, its simulation remains challenging due to complex formation processes and regional variability. We use the EMAC model to assess key factors in nitrate predictions. Increasing grid resolution, reducing dinitrogen pentoxide hydrolysis uptake, and refining emissions improve model performance, although seasonal and diurnal discrepancies persist, requiring further refinement.
Farhan R. Nursanto, Quanfu He, Sophia van de Wouw, Annika Zanders, Thorsten Hohaus, Willem S. J. Kroese, Robert Wegener, Max Gerrit Adam, Benjamin Winter, René Dubus, Lukas Kesper, Franz Rohrer, Yuwei Wang, Emily Matthews, Aristeidis Voliotis, Thomas J. Bannan, Gordon McFiggans, Hugh Coe, Yizhen Wu, Milan Roska, Manjula Canagaratna, Mitch Alton, Matthew M. Coggon, Chelsea E. Stockwell, Kelvin H. Bates, Eva Y. Pfannerstill, Sören R. Zorn, Hui Wang, Matthieu Riva, Sebastien Perrier, Boxing Yang, Lu Liu, Anna Novelli, Michelle Färber, Hendrik Fuchs, Andrea Carolina Marcillo Lara, Achim Grasse, Christian Wesolek, Ralf Tillmann, Rupert Holzinger, Maarten C. Krol, Georgios I. Gkatzelis, and Juliane L. Fry
EGUsphere, https://doi.org/10.5194/egusphere-2025-6310, https://doi.org/10.5194/egusphere-2025-6310, 2026
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Susanne M. C. Scholz, Vlassis A. Karydis, Georgios I. Gkatzelis, Hendrik Fuchs, Spyros N. Pandis, and Alexandra P. Tsimpidi
Geosci. Model Dev., 18, 10119–10142, https://doi.org/10.5194/gmd-18-10119-2025, https://doi.org/10.5194/gmd-18-10119-2025, 2025
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Alexander Hermanns, Anne Caroline Lange, Julia Kowalski, Hendrik Fuchs, and Philipp Franke
Geosci. Model Dev., 18, 9417–9432, https://doi.org/10.5194/gmd-18-9417-2025, https://doi.org/10.5194/gmd-18-9417-2025, 2025
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Lu Liu, Thorsten Hohaus, Andreas Hofzumahaus, Frank Holland, Hendrik Fuchs, Ralf Tillmann, Birger Bohn, Stefanie Andres, Zhaofeng Tan, Franz Rohrer, Vlassis A. Karydis, Vaishali Vardhan, Philipp Franke, Anne C. Lange, Anna Novelli, Benjamin Winter, Changmin Cho, Iulia Gensch, Sergej Wedel, Andreas Wahner, and Astrid Kiendler-Scharr
Atmos. Chem. Phys., 25, 16189–16213, https://doi.org/10.5194/acp-25-16189-2025, https://doi.org/10.5194/acp-25-16189-2025, 2025
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We measured air particles at a rural site in Germany over a year to understand how their sources and properties change with the seasons. Particles from natural sources peaked in summer, especially during heatwaves, while those from burning activities like residential heating and wildfires dominated in colder months. Winds carrying air from other regions also influenced particle levels. These findings link air quality to climate change and energy transitions.
Sungah Kang, Jürgen Wildt, Iida Pullinen, Luc Vereecken, Cheng Wu, Andreas Wahner, Sören R. Zorn, and Thomas F. Mentel
Atmos. Chem. Phys., 25, 15715–15740, https://doi.org/10.5194/acp-25-15715-2025, https://doi.org/10.5194/acp-25-15715-2025, 2025
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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.
Michael Rolletter, Andreas Hofzumahaus, Anna Novelli, Andreas Wahner, and Hendrik Fuchs
Atmos. Chem. Phys., 25, 3481–3502, https://doi.org/10.5194/acp-25-3481-2025, https://doi.org/10.5194/acp-25-3481-2025, 2025
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Highly accurate rate coefficients of termolecular reactions between OH and HO2 radicals and reactive nitrogen oxides were measured for conditions in the lower troposphere, providing improved constraints on recommended values. No dependence on water vapour was found except for the HO2+NO2 reaction, which can be explained by an enhanced rate coefficient of the NO2 reaction with the water complex of the HO2 radical.
Hendrik Fuchs, Aaron Stainsby, Florian Berg, René Dubus, Michelle Färber, Andreas Hofzumahaus, Frank Holland, Kelvin H. Bates, Steven S. Brown, Matthew M. Coggon, Glenn S. Diskin, Georgios I. Gkatzelis, Christopher M. Jernigan, Jeff Peischl, Michael A. Robinson, Andrew W. Rollins, Nell B. Schafer, Rebecca H. Schwantes, Chelsea E. Stockwell, Patrick R. Veres, Carsten Warneke, Eleanor M. Waxman, Lu Xu, Kristen Zuraski, Andreas Wahner, and Anna Novelli
Atmos. Meas. Tech., 18, 881–895, https://doi.org/10.5194/amt-18-881-2025, https://doi.org/10.5194/amt-18-881-2025, 2025
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Significant improvements have been made to the instruments used to measure OH reactivity, which is equivalent to the sum of air pollutant concentrations. Accurate and precise measurements with a high time resolution have been achieved, allowing use on aircraft, as demonstrated during flights in the USA.
Hassnae Erraji, Philipp Franke, Astrid Lampert, Tobias Schuldt, Ralf Tillmann, Andreas Wahner, and Anne Caroline Lange
Atmos. Chem. Phys., 24, 13913–13934, https://doi.org/10.5194/acp-24-13913-2024, https://doi.org/10.5194/acp-24-13913-2024, 2024
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Four-dimensional variational data assimilation allows for the simultaneous optimisation of initial values and emission rates by using trace-gas profiles from drone observations in a regional air quality model. Assimilated profiles positively impact the representation of air pollutants in the model by improving their vertical distribution and ground-level concentrations. This case study highlights the potential of drone data to enhance air quality analyses including local emission evaluation.
Florian Berg, Anna Novelli, René Dubus, Andreas Hofzumahaus, Frank Holland, Andreas Wahner, and Hendrik Fuchs
Atmos. Chem. Phys., 24, 13715–13731, https://doi.org/10.5194/acp-24-13715-2024, https://doi.org/10.5194/acp-24-13715-2024, 2024
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This study reports temperature-dependent rate coefficients of the reaction of atmospherically relevant hydrocarbons from biogenic sources (methyl vinyl ketones and monoterpenes) and anthropogenic sources (alkanes and aromatics). Measurements were done at atmospheric conditions (ambient pressure and temperature range) in air.
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
Preprint archived
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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.
Felix Wieser, Rolf Sander, Changmin Cho, Hendrik Fuchs, Thorsten Hohaus, Anna Novelli, Ralf Tillmann, and Domenico Taraborrelli
Geosci. Model Dev., 17, 4311–4330, https://doi.org/10.5194/gmd-17-4311-2024, https://doi.org/10.5194/gmd-17-4311-2024, 2024
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The chemistry scheme of the atmospheric box model CAABA/MECCA is expanded to achieve an improved aerosol formation from emitted organic compounds. In addition to newly added reactions, temperature-dependent partitioning of all new species between the gas and aqueous phases is estimated and included in the pre-existing scheme. Sensitivity runs show an overestimation of key compounds from isoprene, which can be explained by a lack of aqueous-phase degradation reactions and box model limitations.
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.
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.
Marc von Hobe, Domenico Taraborrelli, Sascha Alber, Birger Bohn, Hans-Peter Dorn, Hendrik Fuchs, Yun Li, Chenxi Qiu, Franz Rohrer, Roberto Sommariva, Fred Stroh, Zhaofeng Tan, Sergej Wedel, and Anna Novelli
Atmos. Chem. Phys., 23, 10609–10623, https://doi.org/10.5194/acp-23-10609-2023, https://doi.org/10.5194/acp-23-10609-2023, 2023
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The trace gas carbonyl sulfide (OCS) transports sulfur from the troposphere to the stratosphere, where sulfate aerosols are formed that influence climate and stratospheric chemistry. An uncertain OCS source in the troposphere is chemical production form dimethyl sulfide (DMS), a gas released in large quantities from the oceans. We carried out experiments in a large atmospheric simulation chamber to further elucidate the chemical mechanism of OCS production from DMS.
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.
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.
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.
Amir H. Souri, Matthew S. Johnson, Glenn M. Wolfe, James H. Crawford, Alan Fried, Armin Wisthaler, William H. Brune, Donald R. Blake, Andrew J. Weinheimer, Tijl Verhoelst, Steven Compernolle, Gaia Pinardi, Corinne Vigouroux, Bavo Langerock, Sungyeon Choi, Lok Lamsal, Lei Zhu, Shuai Sun, Ronald C. Cohen, Kyung-Eun Min, Changmin Cho, Sajeev Philip, Xiong Liu, and Kelly Chance
Atmos. Chem. Phys., 23, 1963–1986, https://doi.org/10.5194/acp-23-1963-2023, https://doi.org/10.5194/acp-23-1963-2023, 2023
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We have rigorously characterized different sources of error in satellite-based HCHO / NO2 tropospheric columns, a widely used metric for diagnosing near-surface ozone sensitivity. Specifically, the errors were categorized/quantified into (i) an inherent chemistry error, (ii) the decoupled relationship between columns and the near-surface concentration, (iii) the spatial representativeness error of ground satellite pixels, and (iv) the satellite retrieval errors.
Tobias Schuldt, Georgios I. Gkatzelis, Christian Wesolek, Franz Rohrer, Benjamin Winter, Thomas A. J. Kuhlbusch, Astrid Kiendler-Scharr, and Ralf Tillmann
Atmos. Meas. Tech., 16, 373–386, https://doi.org/10.5194/amt-16-373-2023, https://doi.org/10.5194/amt-16-373-2023, 2023
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We report in situ measurements of air pollutant concentrations within the planetary boundary layer on board a Zeppelin NT in Germany. We highlight the in-flight evaluation of electrochemical sensors that were installed inside a hatch box located on the bottom of the Zeppelin. Results from this work emphasize the potential of these sensors for other in situ airborne applications, e.g., on board unmanned aerial vehicles (UAVs).
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.
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.
Woohui Nam, Changmin Cho, Begie Perdigones, Tae Siek Rhee, and Kyung-Eun Min
Atmos. Meas. Tech., 15, 4473–4487, https://doi.org/10.5194/amt-15-4473-2022, https://doi.org/10.5194/amt-15-4473-2022, 2022
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We describe our vibration-resistant instrument for measuring ambient NO3, NO2, and H2O based on cavity-enhanced absorption spectroscopy. By simultaneous retrieval of H2O with the other species using a measured H2O absorption spectrum, direct quantifications among all species are possible without any pre-treatment for H2O. Our instrument achieves the effective light path to ~101.5 km, which allows the sensitive measurements of NO3 and NO2 as 1.41 pptv and 6.92 ppbv (1σ) in 1 s.
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.
Ralf Tillmann, Georgios I. Gkatzelis, Franz Rohrer, Benjamin Winter, Christian Wesolek, Tobias Schuldt, Anne C. Lange, Philipp Franke, Elmar Friese, Michael Decker, Robert Wegener, Morten Hundt, Oleg Aseev, and Astrid Kiendler-Scharr
Atmos. Meas. Tech., 15, 3827–3842, https://doi.org/10.5194/amt-15-3827-2022, https://doi.org/10.5194/amt-15-3827-2022, 2022
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We report in situ measurements of air pollutant concentrations within the planetary boundary layer on board a Zeppelin in Germany. The low costs of commercial flights provide an affordable and efficient method to improve our understanding of changes in emissions in space and time. The experimental setup expands the capabilities of this platform and provides insights into primary and secondary pollution observations and planetary boundary layer dynamics which determine air quality significantly.
Andrea Pozzer, Simon F. Reifenberg, Vinod Kumar, Bruno Franco, Matthias Kohl, Domenico Taraborrelli, Sergey Gromov, Sebastian Ehrhart, Patrick Jöckel, Rolf Sander, Veronica Fall, Simon Rosanka, Vlassis Karydis, Dimitris Akritidis, Tamara Emmerichs, Monica Crippa, Diego Guizzardi, Johannes W. Kaiser, Lieven Clarisse, Astrid Kiendler-Scharr, Holger Tost, and Alexandra Tsimpidi
Geosci. Model Dev., 15, 2673–2710, https://doi.org/10.5194/gmd-15-2673-2022, https://doi.org/10.5194/gmd-15-2673-2022, 2022
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A newly developed setup of the chemistry general circulation model EMAC (ECHAM5/MESSy for Atmospheric Chemistry) is evaluated here. A comprehensive organic degradation mechanism is used and coupled with a volatility base model.
The results show that the model reproduces most of the tracers and aerosols satisfactorily but shows discrepancies for oxygenated organic gases. It is also shown that this model configuration can be used for further research in atmospheric chemistry.
Sophie Dixneuf, Albert A. Ruth, Rolf Häseler, Theo Brauers, Franz Rohrer, and Hans-Peter Dorn
Atmos. Meas. Tech., 15, 945–964, https://doi.org/10.5194/amt-15-945-2022, https://doi.org/10.5194/amt-15-945-2022, 2022
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Atmospheric chambers, like SAPHIR in Jülich (Germany), are used to experimentally simulate specific atmospheric scenarios to improve our understanding of the complex chemical reactions occurring in our atmospheres. These facilities hence require cutting-edge gas-sensing capabilities to detect trace gases at the lowest level and in a short time. One important trace gas is HONO, for which we custom-built an optical sensing setup, capable of detecting one HONO molecule in ~40 billion in 1 min.
Zhi-Hui Zhang, Elena Hartner, Battist Utinger, Benjamin Gfeller, Andreas Paul, Martin Sklorz, Hendryk Czech, Bin Xia Yang, Xin Yi Su, Gert Jakobi, Jürgen Orasche, Jürgen Schnelle-Kreis, Seongho Jeong, Thomas Gröger, Michal Pardo, Thorsten Hohaus, Thomas Adam, Astrid Kiendler-Scharr, Yinon Rudich, Ralf Zimmermann, and Markus Kalberer
Atmos. Chem. Phys., 22, 1793–1809, https://doi.org/10.5194/acp-22-1793-2022, https://doi.org/10.5194/acp-22-1793-2022, 2022
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Using a novel setup, we comprehensively characterized the formation of particle-bound reactive oxygen species (ROS) in anthropogenic and biogenic secondary organic aerosols (SOAs). We found that more than 90 % of all ROS components in both SOA types have a short lifetime. Our results also show that photochemical aging promotes particle-bound ROS production and enhances the oxidative potential of the aerosols. We found consistent results between chemical-based and biological-based ROS analyses.
Dongwook Kim, Changmin Cho, Seokhan Jeong, Soojin Lee, Benjamin A. Nault, Pedro Campuzano-Jost, Douglas A. Day, Jason C. Schroder, Jose L. Jimenez, Rainer Volkamer, Donald R. Blake, Armin Wisthaler, Alan Fried, Joshua P. DiGangi, Glenn S. Diskin, Sally E. Pusede, Samuel R. Hall, Kirk Ullmann, L. Gregory Huey, David J. Tanner, Jack Dibb, Christoph J. Knote, and Kyung-Eun Min
Atmos. Chem. Phys., 22, 805–821, https://doi.org/10.5194/acp-22-805-2022, https://doi.org/10.5194/acp-22-805-2022, 2022
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CHOCHO was simulated using a 0-D box model constrained by measurements during the KORUS-AQ mission. CHOCHO concentration was high in large cities, aromatics being the most important precursors. Loss path to aerosol was the highest sink, contributing to ~ 20 % of secondary organic aerosol formation. Our work highlights that simple CHOCHO surface uptake approach is valid only for low aerosol conditions and more work is required to understand CHOCHO solubility in high-aerosol conditions.
Clara M. Nussbaumer, John N. Crowley, Jan Schuladen, Jonathan Williams, Sascha Hafermann, Andreas Reiffs, Raoul Axinte, Hartwig Harder, Cheryl Ernest, Anna Novelli, Katrin Sala, Monica Martinez, Chinmay Mallik, Laura Tomsche, Christian Plass-Dülmer, Birger Bohn, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 21, 18413–18432, https://doi.org/10.5194/acp-21-18413-2021, https://doi.org/10.5194/acp-21-18413-2021, 2021
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HCHO is an important atmospheric trace gas influencing the photochemical processes in the Earth’s atmosphere, including the budget of HOx and the abundance of tropospheric O3. This research presents the photochemical calculations of HCHO and O3 based on three field campaigns across Europe. We show that HCHO production via the oxidation of only four volatile organic compound precursors, i.e., CH4, CH3CHO, C5H8 and CH3OH, can balance the observed loss at all sites well.
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.
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.
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.
Simon Rosanka, Bruno Franco, Lieven Clarisse, Pierre-François Coheur, Andrea Pozzer, Andreas Wahner, and Domenico Taraborrelli
Atmos. Chem. Phys., 21, 11257–11288, https://doi.org/10.5194/acp-21-11257-2021, https://doi.org/10.5194/acp-21-11257-2021, 2021
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The strong El Niño in 2015 led to a particular dry season in Indonesia and favoured severe peatland fires. The smouldering conditions of these fires and the high carbon content of peat resulted in high volatile organic compound (VOC) emissions. By using a comprehensive atmospheric model, we show that these emissions have a significant impact on the tropospheric composition and oxidation capacity. These emissions are transported into to the lower stratosphere, resulting in a depletion of ozone.
Rongrong Wu, Luc Vereecken, Epameinondas Tsiligiannis, Sungah Kang, Sascha R. Albrecht, Luisa Hantschke, Defeng Zhao, Anna Novelli, Hendrik Fuchs, Ralf Tillmann, Thorsten Hohaus, Philip T. M. Carlsson, Justin Shenolikar, François Bernard, John N. Crowley, Juliane L. Fry, Bellamy Brownwood, Joel A. Thornton, Steven S. Brown, Astrid Kiendler-Scharr, Andreas Wahner, Mattias Hallquist, and Thomas F. Mentel
Atmos. Chem. Phys., 21, 10799–10824, https://doi.org/10.5194/acp-21-10799-2021, https://doi.org/10.5194/acp-21-10799-2021, 2021
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Isoprene is the biogenic volatile organic compound with the largest emissions rates. The nighttime reaction of isoprene with the NO3 radical has a large potential to contribute to SOA. We classified isoprene nitrates into generations and proposed formation pathways. Considering the potential functionalization of the isoprene nitrates we propose that mainly isoprene dimers contribute to SOA formation from the isoprene NO3 reactions with at least a 5 % mass yield.
Simon Rosanka, Rolf Sander, Andreas Wahner, and Domenico Taraborrelli
Geosci. Model Dev., 14, 4103–4115, https://doi.org/10.5194/gmd-14-4103-2021, https://doi.org/10.5194/gmd-14-4103-2021, 2021
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The Jülich Aqueous-phase Mechanism of Organic Chemistry (JAMOC) is developed and implemented into the Module Efficiently Calculating the Chemistry of the Atmosphere (MECCA). JAMOC is an explicit in-cloud oxidation scheme for oxygenated volatile organic compounds (OVOCs), which is suitable for global model applications. Within a box-model study, we show that JAMOC yields reduced gas-phase concentrations of most OVOCs and oxidants, except for nitrogen oxides.
Simon Rosanka, Rolf Sander, Bruno Franco, Catherine Wespes, Andreas Wahner, and Domenico Taraborrelli
Atmos. Chem. Phys., 21, 9909–9930, https://doi.org/10.5194/acp-21-9909-2021, https://doi.org/10.5194/acp-21-9909-2021, 2021
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In-cloud destruction of ozone depends on hydroperoxyl radicals in cloud droplets, where they are produced by oxygenated volatile organic compound (OVOC) oxygenation. Only rudimentary representations of these processes, if any, are currently available in global atmospheric models. By using a comprehensive atmospheric model that includes a complex in-cloud OVOC oxidation scheme, we show that atmospheric oxidants are reduced and models ignoring this process will underpredict clouds as ozone sinks.
Defeng Zhao, Iida Pullinen, Hendrik Fuchs, Stephanie Schrade, Rongrong Wu, Ismail-Hakki Acir, Ralf Tillmann, Franz Rohrer, Jürgen Wildt, Yindong Guo, Astrid Kiendler-Scharr, Andreas Wahner, Sungah Kang, Luc Vereecken, and Thomas F. Mentel
Atmos. Chem. Phys., 21, 9681–9704, https://doi.org/10.5194/acp-21-9681-2021, https://doi.org/10.5194/acp-21-9681-2021, 2021
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The reaction of isoprene, a biogenic volatile organic compound with the globally largest emission rates, with NO3, an nighttime oxidant influenced heavily by anthropogenic emissions, forms a large number of highly oxygenated organic molecules (HOM). These HOM are formed via one or multiple oxidation steps, followed by autoxidation. Their total yield is much higher than that in the daytime oxidation of isoprene. They may play an important role in nighttime organic aerosol formation and growth.
Marvin Glowania, Franz Rohrer, Hans-Peter Dorn, Andreas Hofzumahaus, Frank Holland, Astrid Kiendler-Scharr, Andreas Wahner, and Hendrik Fuchs
Atmos. Meas. Tech., 14, 4239–4253, https://doi.org/10.5194/amt-14-4239-2021, https://doi.org/10.5194/amt-14-4239-2021, 2021
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Three instruments that use different techniques to measure gaseous formaldehyde concentrations were compared in experiments in the atmospheric simulation chamber SAPHIR at Forschungszentrum Jülich. The results demonstrated the need to correct the baseline in measurements by instruments that use the Hantzsch reaction or make use of cavity ring-down spectroscopy. After applying corrections, all three methods gave accurate and precise measurements within their specifications.
Clara Betancourt, Christoph Küppers, Tammarat Piansawan, Uta Sager, Andrea B. Hoyer, Heinz Kaminski, Gerhard Rapp, Astrid C. John, Miriam Küpper, Ulrich Quass, Thomas Kuhlbusch, Jochen Rudolph, Astrid Kiendler-Scharr, and Iulia Gensch
Atmos. Chem. Phys., 21, 5953–5964, https://doi.org/10.5194/acp-21-5953-2021, https://doi.org/10.5194/acp-21-5953-2021, 2021
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For the first time, we included stable isotopes in the Lagrangian particle dispersion model FLEXPART to investigate firewood home heating aerosol. This is an innovative source apportionment methodology since comparison of stable isotope ratio model predictions with observations delivers quantitative understanding of atmospheric processes. The main outcome of this study is that the home heating aerosol in residential areas was not of remote origin.
Alexander Zaytsev, Martin Breitenlechner, Anna Novelli, Hendrik Fuchs, Daniel A. Knopf, Jesse H. Kroll, and Frank N. Keutsch
Atmos. Meas. Tech., 14, 2501–2513, https://doi.org/10.5194/amt-14-2501-2021, https://doi.org/10.5194/amt-14-2501-2021, 2021
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We have developed an online method for speciated measurements of organic peroxy radicals and stabilized Criegee intermediates using chemical derivatization combined with chemical ionization mass spectrometry. Chemical derivatization prevents secondary radical reactions and eliminates potential interferences. Comparison between our measurements and results from numeric modeling shows that the method can be used for the quantification of a wide range of atmospheric radicals and intermediates.
Michael Priestley, Thomas J. Bannan, Michael Le Breton, Stephen D. Worrall, Sungah Kang, Iida Pullinen, Sebastian Schmitt, Ralf Tillmann, Einhard Kleist, Defeng Zhao, Jürgen Wildt, Olga Garmash, Archit Mehra, Asan Bacak, Dudley E. Shallcross, Astrid Kiendler-Scharr, Åsa M. Hallquist, Mikael Ehn, Hugh Coe, Carl J. Percival, Mattias Hallquist, Thomas F. Mentel, and Gordon McFiggans
Atmos. Chem. Phys., 21, 3473–3490, https://doi.org/10.5194/acp-21-3473-2021, https://doi.org/10.5194/acp-21-3473-2021, 2021
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A significant fraction of emissions from human activity consists of aromatic hydrocarbons, e.g. benzene, which oxidise to form new compounds important for particle growth. Characterisation of benzene oxidation products highlights the range of species produced as well as their chemical properties and contextualises them within relevant frameworks, e.g. MCM. Cluster analysis of the oxidation product time series distinguishes behaviours of CHON compounds that could aid in identifying functionality.
Cited articles
Atkinson, R., Baulch, D. L., Cox, R. A., Crowley, J. N., Hampson, R. F., Hynes, R. G., Jenkin, M. E., Rossi, M. J., and Troe, J.: Evaluated kinetic and photochemical data for atmospheric chemistry: Volume I - gas phase reactions of Ox, HOx, NOx and SOx species, Atmos. Chem. Phys., 4, 1461–1738, https://doi.org/10.5194/acp-4-1461-2004, 2004.
Atkinson, R., Baulch, D. L., Cox, R. A., Crowley, J. N., Hampson, R. F., Hynes, R. G., Jenkin, M. E., Rossi, M. J., Troe, J., and IUPAC Subcommittee: Evaluated kinetic and photochemical data for atmospheric chemistry: Volume II – gas phase reactions of organic species, Atmos. Chem. Phys., 6, 3625–4055, https://doi.org/10.5194/acp-6-3625-2006, 2006.
Berndt, T.: Formation of carbonyls and hydroperoxyenals (HPALDs) from the OH
radical reaction of isoprene for low-NOx conditions: influence of
temperature and water vapour content, J. Atmos. Chem., 69, 253–272,
https://doi.org/10.1007/s10874-012-9245-2, 2012.
Berndt, T., Hyttinen, N., Herrmann, H., and Hansel, A.: First oxidation
products from the reaction of hydroxyl radicals with isoprene for pristine
environmental conditions, Comm. Chem., 2, 21, https://doi.org/10.1038/s42004-019-0120-9,
2019.
Berresheim, H., Elste, T., Plass-Dülmer, C., Eiseleb, F. L., and
Tannerb, D. J.: Chemical ionization mass spectrometer for long-term
measurements of atmospheric OH and H2SO4, Int. J. Mass Spectrom., 202,
91–109, https://doi.org/10.1016/S1387-3806(00)00233-5, 2000.
Bohn, B. and Zilken, H.: Model-aided radiometric determination of photolysis frequencies in a sunlit atmosphere simulation chamber, Atmos. Chem. Phys., 5, 191–206, https://doi.org/10.5194/acp-5-191-2005, 2005.
Bohn, B., Rohrer, F., Brauers, T., and Wahner, A.: Actinometric measurements of NO2 photolysis frequencies in the atmosphere simulation chamber SAPHIR, Atmos. Chem. Phys., 5, 493–503, https://doi.org/10.5194/acp-5-493-2005, 2005.
Brune, W. H., Baier, B. C., Thomas, J., Ren, X., Cohen, R. C., Pusede, S.
E., Browne, E. C., Goldstein, A. H., Gentner, D. R., Keutsch, F. N.,
Thornton, J. A., Harrold, S., Lopez-Hilfiker, F. D., and Wennberg, P. O.:
Ozone production chemistry in the presence of urban plumes, Faraday
Discuss., 189, 169–189, https://doi.org/10.1039/C5FD00204D, 2016.
Carslaw, K. S., Boucher, O., Spracklen, D. V., Mann, G. W., Rae, J. G. L., Woodward, S., and Kulmala, M.: A review of natural aerosol interactions and feedbacks within the Earth system, Atmos. Chem. Phys., 10, 1701–1737, https://doi.org/10.5194/acp-10-1701-2010, 2010.
Cho, C., Hofzumahaus, A., Fuchs, H., Dorn, H.-P., Glowania, M., Holland, F., Rohrer, F., Vardhan, V., Kiendler-Scharr, A., Wahner, A., and Novelli, A.:
Characterization and application of a chemical modulation reactor during the JULIAC campaign, V1, Jülich DATA, https://doi.org/10.26165/JUELICH-DATA/GK7PJQ, 2021.
Crounse, J. D., Paulot, F., Kjaergaard, H. G., and Wennberg, P. O.: Peroxy
radical isomerization in the oxidation of isoprene, Phys. Chem. Chem. Phys.,
13, 13607–13613, https://doi.org/10.1039/C1CP21330J, 2011.
Crounse, J. D., Knap, H. C., Ørnsø, K. B., Jørgensen, S., Paulot,
F., Kjaergaard, H. G., and Wennberg, P. O.: Atmospheric Fate of
Methacrolein. 1. Peroxy Radical Isomerization Following Addition of OH and
O2, J. Phys. Chem. A, 116, 5756–5762, https://doi.org/10.1021/jp211560u, 2012.
da Silva, G., Graham, C., and Wang, Z.-F.: Unimolecular β-hydroxyperoxy radical decomposition with OH recycling in the photochemical
oxidation of isoprene, Environ. Sci. Technol., 44, 250–256,
https://doi.org/10.1021/es900924d, 2010.
Dorn, H. P., Neuroth, R., and Hofzumahaus, A.: Investigation of OH
absorption cross sections of rotational transitions in the A26+, ν0=0<X25, ν00=0 band under atmospheric conditions:
Implications for tropospheric long-path absorption measurements, J. Geophys.
Res., 100, 7397–7409, 1995.
Dorn, H.-P., Apodaca, R. L., Ball, S. M., Brauers, T., Brown, S. S., Crowley, J. N., Dubé, W. P., Fuchs, H., Häseler, R., Heitmann, U., Jones, R. L., Kiendler-Scharr, A., Labazan, I., Langridge, J. M., Meinen, J., Mentel, T. F., Platt, U., Pöhler, D., Rohrer, F., Ruth, A. A., Schlosser, E., Schuster, G., Shillings, A. J. L., Simpson, W. R., Thieser, J., Tillmann, R., Varma, R., Venables, D. S., and Wahner, A.: Intercomparison of NO3 radical detection instruments in the atmosphere simulation chamber SAPHIR, Atmos. Meas. Tech., 6, 1111–1140, https://doi.org/10.5194/amt-6-1111-2013, 2013.
Dubey, M. K., Hanisco, T. F., Wennberg, P. O., and Anderson, J. G.:
Monitoring potential photochemical interference in laser-induced
fluorescence measurements of atmospheric OH, Geophys. Res. Lett., 23,
3215–3218, https://doi.org/10.1029/96gl03008, 1996.
Eisele, F. L., and Tanner, D. J.: Ion-assisted tropospheric OH measurements,
J. Geophys. Res.-Atmos., 96, 9295–9308, https://doi.org/10.1029/91JD00198, 1991.
Feiner, P. A., Brune, W. H., Miller, D. O., Zhang, L., Cohen, R. C., Romer,
P. S., Goldstein, A. H., Keutsch, F. N., Skog, K. M., Wennberg, P. O.,
Nguyen, T. B., Teng, A. P., DeGouw, J., Koss, A., Wild, R. J., Brown, S. S.,
Guenther, A., Edgerton, E., Baumann, K., and Fry, J. L.: Testing atmospheric
oxidation in an Alabama forest, J. Atmos. Sci., 73, 4699–4710,
https://doi.org/10.1175/jas-d-16-0044.1, 2016.
Fuchs, H., Holland, F., and Hofzumahaus, A.: Measurement of tropospheric
RO2 and HO2 radicals by a laser-induced fluorescence instrument,
Rev. Sci. Instrum., 79, 084104, https://doi.org/10.1063/1.2968712, 2008.
Fuchs, H., Dubé, W. P., Lerner, B. M., Wagner, N. L., Williams, E. J.,
and Brown, S. S.: A Sensitive and Versatile Detector for Atmospheric NO2 and NOx Based on Blue Diode Laser Cavity Ring-Down Spectroscopy, Environ. Sci.
Technol., 43, 7831–7836, https://doi.org/10.1021/es902067h, 2009.
Fuchs, H., Ball, S. M., Bohn, B., Brauers, T., Cohen, R. C., Dorn, H.-P., Dubé, W. P., Fry, J. L., Häseler, R., Heitmann, U., Jones, R. L., Kleffmann, J., Mentel, T. F., Müsgen, P., Rohrer, F., Rollins, A. W., Ruth, A. A., Kiendler-Scharr, A., Schlosser, E., Shillings, A. J. L., Tillmann, R., Varma, R. M., Venables, D. S., Villena Tapia, G., Wahner, A., Wegener, R., Wooldridge, P. J., and Brown, S. S.: Intercomparison of measurements of NO2 concentrations in the atmosphere simulation chamber SAPHIR during the NO3Comp campaign, Atmos. Meas. Tech., 3, 21–37, https://doi.org/10.5194/amt-3-21-2010, 2010a.
Fuchs, H., Brauers, T., Dorn, H.-P., Harder, H., Häseler, R., Hofzumahaus, A., Holland, F., Kanaya, Y., Kajii, Y., Kubistin, D., Lou, S., Martinez, M., Miyamoto, K., Nishida, S., Rudolf, M., Schlosser, E., Wahner, A., Yoshino, A., and Schurath, U.: Technical Note: Formal blind intercomparison of HO2 measurements in the atmosphere simulation chamber SAPHIR during the HOxComp campaign, Atmos. Chem. Phys., 10, 12233–12250, https://doi.org/10.5194/acp-10-12233-2010, 2010b.
Fuchs, H., Bohn, B., Hofzumahaus, A., Holland, F., Lu, K. D., Nehr, S., Rohrer, F., and Wahner, A.: Detection of HO2 by laser-induced fluorescence: calibration and interferences from RO2 radicals, Atmos. Meas. Tech., 4, 1209–1225, https://doi.org/10.5194/amt-4-1209-2011, 2011.
Fuchs, H., Dorn, H.-P., Bachner, M., Bohn, B., Brauers, T., Gomm, S., Hofzumahaus, A., Holland, F., Nehr, S., Rohrer, F., Tillmann, R., and Wahner, A.: Comparison of OH concentration measurements by DOAS and LIF during SAPHIR chamber experiments at high OH reactivity and low NO concentration, Atmos. Meas. Tech., 5, 1611–1626, https://doi.org/10.5194/amt-5-1611-2012, 2012a.
Fuchs, H., Simpson, W. R., Apodaca, R. L., Brauers, T., Cohen, R. C., Crowley, J. N., Dorn, H.-P., Dubé, W. P., Fry, J. L., Häseler, R., Kajii, Y., Kiendler-Scharr, A., Labazan, I., Matsumoto, J., Mentel, T. F., Nakashima, Y., Rohrer, F., Rollins, A. W., Schuster, G., Tillmann, R., Wahner, A., Wooldridge, P. J., and Brown, S. S.: Comparison of N2O5 mixing ratios during NO3Comp 2007 in SAPHIR, Atmos. Meas. Tech., 5, 2763–2777, https://doi.org/10.5194/amt-5-2763-2012, 2012b.
Fuchs, H., Hofzumahaus, A., Rohrer, F., Bohn, B., Brauers, T., Dorn, H. P.,
Häseler, R., Holland, F., Kaminski, M., Li, X., Lu, K., Nehr, S.,
Tillmann, R., Wegener, R., and Wahner, A.: Experimental evidence for
efficient hydroxyl radical regeneration in isoprene oxidation, Nat. Geosci.,
6, 1023–1026, https://doi.org/10.1038/ngeo1964, 2013.
Fuchs, H., Acir, I.-H., Bohn, B., Brauers, T., Dorn, H.-P., Häseler, R., Hofzumahaus, A., Holland, F., Kaminski, M., Li, X., Lu, K., Lutz, A., Nehr, S., Rohrer, F., Tillmann, R., Wegener, R., and Wahner, A.: OH regeneration from methacrolein oxidation investigated in the atmosphere simulation chamber SAPHIR, Atmos. Chem. Phys., 14, 7895–7908, https://doi.org/10.5194/acp-14-7895-2014, 2014.
Fuchs, H., Tan, Z., Hofzumahaus, A., Broch, S., Dorn, H.-P., Holland, F., Künstler, C., Gomm, S., Rohrer, F., Schrade, S., Tillmann, R., and Wahner, A.: Investigation of potential interferences in the detection of atmospheric ROx radicals by laser-induced fluorescence under dark conditions, Atmos. Meas. Tech., 9, 1431–1447, https://doi.org/10.5194/amt-9-1431-2016, 2016.
Fuchs, H., Novelli, A., Rolletter, M., Hofzumahaus, A., Pfannerstill, E. Y., Kessel, S., Edtbauer, A., Williams, J., Michoud, V., Dusanter, S., Locoge, N., Zannoni, N., Gros, V., Truong, F., Sarda-Esteve, R., Cryer, D. R., Brumby, C. A., Whalley, L. K., Stone, D., Seakins, P. W., Heard, D. E., Schoemaecker, C., Blocquet, M., Coudert, S., Batut, S., Fittschen, C., Thames, A. B., Brune, W. H., Ernest, C., Harder, H., Muller, J. B. A., Elste, T., Kubistin, D., Andres, S., Bohn, B., Hohaus, T., Holland, F., Li, X., Rohrer, F., Kiendler-Scharr, A., Tillmann, R., Wegener, R., Yu, Z., Zou, Q., and Wahner, A.: Comparison of OH reactivity measurements in the atmospheric simulation chamber SAPHIR, Atmos. Meas. Tech., 10, 4023–4053, https://doi.org/10.5194/amt-10-4023-2017, 2017a.
Fuchs, H., Tan, Z., Lu, K., Bohn, B., Broch, S., Brown, S. S., Dong, H., Gomm, S., Häseler, R., He, L., Hofzumahaus, A., Holland, F., Li, X., Liu, Y., Lu, S., Min, K.-E., Rohrer, F., Shao, M., Wang, B., Wang, M., Wu, Y., Zeng, L., Zhang, Y., Wahner, A., and Zhang, Y.: OH reactivity at a rural site (Wangdu) in the North China Plain: contributions from OH reactants and experimental OH budget, Atmos. Chem. Phys., 17, 645–661, https://doi.org/10.5194/acp-17-645-2017, 2017b.
Fuchs, H., Albrecht, S., Acir, I., Bohn, B., Breitenlechner, M., Dorn, H.-P., Gkatzelis, G. I., Hofzumahaus, A., Holland, F., Kaminski, M., Keutsch, F. N., Novelli, A., Reimer, D., Rohrer, F., Tillmann, R., Vereecken, L., Wegener, R., Zaytsev, A., Kiendler-Scharr, A., and Wahner, A.: Investigation of the oxidation of methyl vinyl ketone (MVK) by OH radicals in the atmospheric simulation chamber SAPHIR, Atmos. Chem. Phys., 18, 8001–8016, https://doi.org/10.5194/acp-18-8001-2018, 2018.
Griffith, S. M., Hansen, R. F., Dusanter, S., Michoud, V., Gilman, J. B.,
Kuster, W. C., Veres, P. R., Graus, M., de Gouw, J. A., Roberts, J., Young,
C., Washenfelder, R., Brown, S. S., Thalman, R., Waxman, E., Volkamer, R.,
Tsai, C., Stutz, J., Flynn, J. H., Grossberg, N., Lefer, B., Alvarez, S. L.,
Rappenglueck, B., Mielke, L. H., Osthoff, H. D., and Stevens, P. S.:
Measurements of hydroxyl and hydroperoxy radicals during CalNex-LA: Model
comparisons and radical budgets, J. Geophys. Res.-Atmos., 121, 4211–4232,
https://doi.org/10.1002/2015jd024358, 2016.
Hausmann, M., Brandenburger, U., Brauers, T., and Dorn, H.-P.: Detection of
tropospheric OH radicals by long-path differential optical-absorption
spectroscopy: Experimental setup, accuracy, and precision, J. Geophys. Res.,
102, 16011–16022, 1997.
Hens, K., Novelli, A., Martinez, M., Auld, J., Axinte, R., Bohn, B., Fischer, H., Keronen, P., Kubistin, D., Nölscher, A. C., Oswald, R., Paasonen, P., Petäjä, T., Regelin, E., Sander, R., Sinha, V., Sipilä, M., Taraborrelli, D., Tatum Ernest, C., Williams, J., Lelieveld, J., and Harder, H.: Observation and modelling of HOx radicals in a boreal forest, Atmos. Chem. Phys., 14, 8723–8747, https://doi.org/10.5194/acp-14-8723-2014, 2014.
Hofzumahaus, A., Aschmutat, U., Heßling, M., Holland, F., and Ehhalt, D.
H.: The measurement of tropospheric OH radicals by laser-induced
fluorescence spectroscopy during the POPCORN Field Campaign, Geophys. Res.
Lett., 23, 2541–2544, https://doi.org/10.1029/96gl02205, 1996.
Hofzumahaus, A., Aschmutat, U., Brandenburger, U., Brauers, T., Dorn, H. P.,
Hausmann, M., Heßling, M., Holland, F., Plass-Dülmer, C., and
Ehhalt, D. H.: Intercomparison of Tropospheric OH Measurements by Different
Laser Techniques during the POPCORN Campaign 1994, J. Atmos. Chem., 31,
227–246, https://doi.org/10.1023/A:1006014707617, 1998.
Hofzumahaus, A., Rohrer, F., Lu, K., Bohn, B., Brauers, T., Chang, C.-C.,
Fuchs, H., Holland, F., Kita, K., Kondo, Y., Li, X., Lou, S., Shao, M.,
Zeng, L., Wahner, A., and Zhang, Y.: Amplified trace gas removal in the
troposphere, Science, 324, 1702–1704, https://doi.org/10.1126/science.1164566, 2009.
Hofzumahaus, A. and Heard, D. H.: Assessment of local HOx and ROx
measurement techniques: achivements, challenges, and future directions -
Outcomes of the 2015 international HOx workshop, Forschungszentrum
Jülich, Jülich, 23–25 March 2015, 20–21, 2016.
Holland, F., Aschmutat, U., Heßling, M., Hofzumahaus, A., and Ehhalt, D.
H.: Highly Time Resolved Measurements of OH during POPCORN Using
Laser-Induced Fluorescence Spectroscopy, in: Atmospheric Measurements during
POPCORN – Characterisation of the Photochemistry over a Rural Area, edited
by: Rudolph, J. and Koppmann, R., Springer Netherlands, Dordrecht, 205–225,
1998.
Holland, F., Hofzumahaus, A., Schäfer, J., Kraus, A., and Pätz,
H.-W.: Measurements of OH and HO2 radical concentrations and photolysis
frequencies during BERLIOZ, J. Geophys. Res.-Atmos., 108, 8246,
https://doi.org/10.1029/2001jd001393, 2003.
Kleffmann, J., Lörzer, J. C., Wiesen, P., Kern, C., Trick, S., Volkamer,
R., Rodenas, M., and Wirtz, K.: Intercomparison of the DOAS and LOPAP
techniques for the detection of nitrous acid (HONO), Atmos. Environ., 40,
3640–3652, https://doi.org/10.1016/j.atmosenv.2006.03.027, 2006.
Kubistin, D., Harder, H., Martinez, M., Rudolf, M., Sander, R., Bozem, H., Eerdekens, G., Fischer, H., Gurk, C., Klüpfel, T., Königstedt, R., Parchatka, U., Schiller, C. L., Stickler, A., Taraborrelli, D., Williams, J., and Lelieveld, J.: Hydroxyl radicals in the tropical troposphere over the Suriname rainforest: comparison of measurements with the box model MECCA, Atmos. Chem. Phys., 10, 9705–9728, https://doi.org/10.5194/acp-10-9705-2010, 2010.
Lelieveld, J., Butler, T. M., Crowley, J. N., Dillon, T. J., Fischer, H.,
Ganzeveld, L., Harder, H., Lawrence, M. G., Martinez, M., Taraborrelli, D.,
and Williams, J.: Atmospheric oxidation capacity sustained by a tropical
forest, Nature, 452, 737, https://doi.org/10.1038/nature06870, 2008.
Levy, H.: Normal atmosphere: Large radical and formaldehyde concentrations
predicted, Science, 173, 141, https://doi.org/10.1126/science.173.3992.141, 1971.
Lew, M. M., Rickly, P. S., Bottorff, B. P., Reidy, E., Sklaveniti, S., Léonardis, T., Locoge, N., Dusanter, S., Kundu, S., Wood, E., and Stevens, P. S.: OH and HO2 radical chemistry in a midlatitude forest: measurements and model comparisons, Atmos. Chem. Phys., 20, 9209–9230, https://doi.org/10.5194/acp-20-9209-2020, 2020.
Li, K., Jacob, D. J., Liao, H., Zhu, J., Shah, V., Shen, L., Bates, K. H.,
Zhang, Q., and Zhai, S.: A two-pollutant strategy for improving ozone and
particulate air quality in China, Nat. Geosci., 12, 906–910,
https://doi.org/10.1038/s41561-019-0464-x, 2019.
Li, X., Rohrer, F., Hofzumahaus, A., Brauers, T., Häseler, R., Bohn, B.,
Broch, S., Fuchs, H., Gomm, S., Holland, F., Jäger, J., Kaiser, J.,
Keutsch, F. N., Lohse, I., Lu, K., Tillmann, R., Wegener, R., Wolfe, G. M.,
Mentel, T. F., Kiendler-Scharr, A., and Wahner, A.: Missing gas-phase source
of HONO Inferred from zeppelin measurements in the troposphere, Science,
344, 292–296, https://doi.org/10.1126/science.1248999, 2014.
Lou, S., Holland, F., Rohrer, F., Lu, K., Bohn, B., Brauers, T., Chang, C. C., Fuchs, H., Häseler, R., Kita, K., Kondo, Y., Li, X., Shao, M., Zeng, L., Wahner, A., Zhang, Y., Wang, W., and Hofzumahaus, A.: Atmospheric OH reactivities in the Pearl River Delta – China in summer 2006: measurement and model results, Atmos. Chem. Phys., 10, 11243–11260, https://doi.org/10.5194/acp-10-11243-2010, 2010.
Lu, K. D., Rohrer, F., Holland, F., Fuchs, H., Bohn, B., Brauers, T., Chang, C. C., Häseler, R., Hu, M., Kita, K., Kondo, Y., Li, X., Lou, S. R., Nehr, S., Shao, M., Zeng, L. M., Wahner, A., Zhang, Y. H., and Hofzumahaus, A.: Observation and modelling of OH and HO2 concentrations in the Pearl River Delta 2006: a missing OH source in a VOC rich atmosphere, Atmos. Chem. Phys., 12, 1541–1569, https://doi.org/10.5194/acp-12-1541-2012, 2012.
Lu, K. D., Hofzumahaus, A., Holland, F., Bohn, B., Brauers, T., Fuchs, H., Hu, M., Häseler, R., Kita, K., Kondo, Y., Li, X., Lou, S. R., Oebel, A., Shao, M., Zeng, L. M., Wahner, A., Zhu, T., Zhang, Y. H., and Rohrer, F.: Missing OH source in a suburban environment near Beijing: observed and modelled OH and HO2 concentrations in summer 2006, Atmos. Chem. Phys., 13, 1057–1080, https://doi.org/10.5194/acp-13-1057-2013, 2013.
Ma, X., Tan, Z., Lu, K., Yang, X., Liu, Y., Li, S., Li, X., Chen, S.,
Novelli, A., Cho, C., Zeng, L., Wahner, A., and Zhang, Y.: Winter
photochemistry in Beijing: Observation and model simulation of OH and
HO2 radicals at an urban site, Sci. Tot. Environ., 685, 85–95,
https://doi.org/10.1016/j.scitotenv.2019.05.329, 2019.
Mallik, C., Tomsche, L., Bourtsoukidis, E., Crowley, J. N., Derstroff, B., Fischer, H., Hafermann, S., Hüser, I., Javed, U., Keßel, S., Lelieveld, J., Martinez, M., Meusel, H., Novelli, A., Phillips, G. J., Pozzer, A., Reiffs, A., Sander, R., Taraborrelli, D., Sauvage, C., Schuladen, J., Su, H., Williams, J., and Harder, H.: Oxidation processes in the eastern Mediterranean atmosphere: evidence from the modelling of HOx measurements over Cyprus, Atmos. Chem. Phys., 18, 10825–10847, https://doi.org/10.5194/acp-18-10825-2018, 2018.
Mao, J., Ren, X., Zhang, L., Van Duin, D. M., Cohen, R. C., Park, J.-H., Goldstein, A. H., Paulot, F., Beaver, M. R., Crounse, J. D., Wennberg, P. O., DiGangi, J. P., Henry, S. B., Keutsch, F. N., Park, C., Schade, G. W., Wolfe, G. M., Thornton, J. A., and Brune, W. H.: Insights into hydroxyl measurements and atmospheric oxidation in a California forest, Atmos. Chem. Phys., 12, 8009–8020, https://doi.org/10.5194/acp-12-8009-2012, 2012.
Mauldin, R., Kosciuch, E., Eisele, F., Huey, G., Tanner, D., Sjostedt, S.,
Blake, D., Chen, G., Crawford, J., and Davis, D.: South Pole Antarctica
observations and modeling results: New insights on HOx radical and sulfur
chemistry, Atmos. Environ., 44, 572–581, https://doi.org/10.1016/j.atmosenv.2009.07.058,
2010.
Møller, K. H., Bates, K. H., and Kjaergaard, H. G.: The importance of
peroxy radical hydrogen-shift reactions in atmospheric isoprene oxidation,
J. Phys. Chem. A, 123, 920–932, https://doi.org/10.1021/acs.jpca.8b10432, 2019.
Novelli, A., Hens, K., Tatum Ernest, C., Kubistin, D., Regelin, E., Elste, T., Plass-Dülmer, C., Martinez, M., Lelieveld, J., and Harder, H.: Characterisation of an inlet pre-injector laser-induced fluorescence instrument for the measurement of atmospheric hydroxyl radicals, Atmos. Meas. Tech., 7, 3413–3430, https://doi.org/10.5194/amt-7-3413-2014, 2014a.
Novelli, A., Vereecken, L., Lelieveld, J., and Harder, H.: Direct
observation of OH formation from stabilised Criegee intermediates, Phys.
Chem. Chem. Phys, 16, 19941–19951, https://doi.org/10.1039/C4CP02719A, 2014b.
Novelli, A., Hens, K., Tatum Ernest, C., Martinez, M., Nölscher, A. C., Sinha, V., Paasonen, P., Petäjä, T., Sipilä, M., Elste, T., Plass-Dülmer, C., Phillips, G. J., Kubistin, D., Williams, J., Vereecken, L., Lelieveld, J., and Harder, H.: Estimating the atmospheric concentration of Criegee intermediates and their possible interference in a FAGE-LIF instrument, Atmos. Chem. Phys., 17, 7807–7826, https://doi.org/10.5194/acp-17-7807-2017, 2017.
Novelli, A., Kaminski, M., Rolletter, M., Acir, I.-H., Bohn, B., Dorn, H.-P., Li, X., Lutz, A., Nehr, S., Rohrer, F., Tillmann, R., Wegener, R., Holland, F., Hofzumahaus, A., Kiendler-Scharr, A., Wahner, A., and Fuchs, H.: Evaluation of OH and HO2 concentrations and their budgets during photooxidation of 2-methyl-3-butene-2-ol (MBO) in the atmospheric simulation chamber SAPHIR, Atmos. Chem. Phys., 18, 11409–11422, https://doi.org/10.5194/acp-18-11409-2018, 2018.
Novelli, A., Vereecken, L., Bohn, B., Dorn, H.-P., Gkatzelis, G. I., Hofzumahaus, A., Holland, F., Reimer, D., Rohrer, F., Rosanka, S., Taraborrelli, D., Tillmann, R., Wegener, R., Yu, Z., Kiendler-Scharr, A., Wahner, A., and Fuchs, H.: Importance of isomerization reactions for OH radical regeneration from the photo-oxidation of isoprene investigated in the atmospheric simulation chamber SAPHIR, Atmos. Chem. Phys., 20, 3333–3355, https://doi.org/10.5194/acp-20-3333-2020, 2020.
Peeters, J., Nguyen, T., and Vereecken, L.: HOx radical regeneration in the
oxidation of isoprene, Phys. Chem. Chem. Phys, 11, 5935–5939,
https://doi.org/10.1039/b908511d, 2009.
Peeters, J., and Müller, J.-F.: HOx radical regeneration in isoprene
oxidation via peroxy radical isomerisations. II: experimental evidence and
global impact, Phys. Chem. Chem. Phys, 12, 14227–14235,
https://doi.org/10.1039/C0CP00811G, 2010.
Peeters, J., Müller, J. F., Stavrakou, T., and Vinh Son, N.: Hydroxyl
radical recycling in isoprene oxidation driven by hydrogen bonding and
hydrogen tunneling: The upgraded LIM1 mechanism, J. Phys. Chem.. A, 118,
https://doi.org/10.1021/jp5033146, 2014.
Ren, X., Harder, H., Martinez, M., Faloona, I. C., Tan, D., Lesher, R. L.,
Di Carlo, P., Simpas, J. B., and Brune, W. H.: Interference testing for
atmospheric HOx measurements by laser-induced fluorescence, J. Atmos. Chem.,
47, 169-190, https://doi.org/10.1023/b:Joch.0000021037.46866.81, 2004.
Rickly, P. and Stevens, P. S.: Measurements of a potential interference with laser-induced fluorescence measurements of ambient OH from the ozonolysis of biogenic alkenes, Atmos. Meas. Tech., 11, 1–16, https://doi.org/10.5194/amt-11-1-2018, 2018.
Rohrer, F., Bohn, B., Brauers, T., Brüning, D., Johnen, F.-J., Wahner, A., and Kleffmann, J.: Characterisation of the photolytic HONO-source in the atmosphere simulation chamber SAPHIR, Atmos. Chem. Phys., 5, 2189–2201, https://doi.org/10.5194/acp-5-2189-2005, 2005.
Rohrer, F., Lu, K., Hofzumahaus, A., Bohn, B., Brauers, T., Chang, C.-C.,
Fuchs, H., Häseler, R., Holland, F., Hu, M., Kita, K., Kondo, Y., Li,
X., Lou, S., Oebel, A., Shao, M., Zeng, L., Zhu, T., Zhang, Y., and Wahner,
A.: Maximum efficiency in the hydroxyl-radical-based self-cleansing of the
troposphere, Nat. Geosci., 7, 559, https://doi.org/10.1038/ngeo2199, 2014.
Rolletter, M., Kaminski, M., Acir, I.-H., Bohn, B., Dorn, H.-P., Li, X., Lutz, A., Nehr, S., Rohrer, F., Tillmann, R., Wegener, R., Hofzumahaus, A., Kiendler-Scharr, A., Wahner, A., and Fuchs, H.: Investigation of the α-pinene photooxidation by OH in the atmospheric simulation chamber SAPHIR, Atmos. Chem. Phys., 19, 11635–11649, https://doi.org/10.5194/acp-19-11635-2019, 2019.
Rozhenshtein, V. B., Gershenzon, Y. M., Il'in, S. D., and Kishkovich, O. P.:
Study of reactions of HO2 radicals by means of combined ESR/LMR
spectrometer. Destruction on surface, Kinet. Catal., 26, 7248224, available at: https://www.osti.gov/biblio/7248224 1985.
Schlosser, E., Bohn, B., Brauers, T., Dorn, H.-P., Fuchs, H., Häseler,
R., Hofzumahaus, A., Holland, F., Rohrer, F., Rupp, L. O., Siese, M.,
Tillmann, R., and Wahner, A.: Intercomparison of two hydroxyl radical
measurement techniques at the atmosphere simulation chamber SAPHIR, J.
Atmos. Chem., 56, 187–205, https://doi.org/10.1007/s10874-006-9049-3, 2007.
Schlosser, E., Brauers, T., Dorn, H.-P., Fuchs, H., Häseler, R., Hofzumahaus, A., Holland, F., Wahner, A., Kanaya, Y., Kajii, Y., Miyamoto, K., Nishida, S., Watanabe, K., Yoshino, A., Kubistin, D., Martinez, M., Rudolf, M., Harder, H., Berresheim, H., Elste, T., Plass-Dülmer, C., Stange, G., and Schurath, U.: Technical Note: Formal blind intercomparison of OH measurements: results from the international campaign HOxComp, Atmos. Chem. Phys., 9, 7923–7948, https://doi.org/10.5194/acp-9-7923-2009, 2009.
Sinha, V., Williams, J., Crowley, J. N., and Lelieveld, J.: The Comparative Reactivity Method – a new tool to measure total OH Reactivity in ambient air, Atmos. Chem. Phys., 8, 2213–2227, https://doi.org/10.5194/acp-8-2213-2008, 2008.
Stone, D., Evans, M. J., Edwards, P. M., Commane, R., Ingham, T., Rickard, A. R., Brookes, D. M., Hopkins, J., Leigh, R. J., Lewis, A. C., Monks, P. S., Oram, D., Reeves, C. E., Stewart, D., and Heard, D. E.: Isoprene oxidation mechanisms: measurements and modelling of OH and HO2 over a South-East Asian tropical rainforest during the OP3 field campaign, Atmos. Chem. Phys., 11, 6749–6771, https://doi.org/10.5194/acp-11-6749-2011, 2011.
Stone, D., Whalley, L. K., and Heard, D. E.: Tropospheric OH and HO2
radicals: field measurements and model comparisons, Chem. Soc. Rev., 41,
6348–6404, https://doi.org/10.1039/C2CS35140D, 2012.
Tan, D., Faloona, I., Simpas, J. B., Brune, W., Shepson, P. B., Couch, T.
L., Sumner, A. L., Carroll, M. A., Thornberry, T., Apel, E., Riemer, D., and
Stockwell, W.: HO x budgets in a deciduous forest: Results from the PROPHET
summer 1998 campaign, J. Geophys. Res.-Atmos., 106, 24407–24427,
https://doi.org/10.1029/2001jd900016, 2001.
Tan, Z., Fuchs, H., Lu, K., Hofzumahaus, A., Bohn, B., Broch, S., Dong, H., Gomm, S., Häseler, R., He, L., Holland, F., Li, X., Liu, Y., Lu, S., Rohrer, F., Shao, M., Wang, B., Wang, M., Wu, Y., Zeng, L., Zhang, Y., Wahner, A., and Zhang, Y.: Radical chemistry at a rural site (Wangdu) in the North China Plain: observation and model calculations of OH, HO2 and RO2 radicals, Atmos. Chem. Phys., 17, 663–690, https://doi.org/10.5194/acp-17-663-2017, 2017.
Tan, Z., Rohrer, F., Lu, K., Ma, X., Bohn, B., Broch, S., Dong, H., Fuchs, H., Gkatzelis, G. I., Hofzumahaus, A., Holland, F., Li, X., Liu, Y., Liu, Y., Novelli, A., Shao, M., Wang, H., Wu, Y., Zeng, L., Hu, M., Kiendler-Scharr, A., Wahner, A., and Zhang, Y.: Wintertime photochemistry in Beijing: observations of ROx radical concentrations in the North China Plain during the BEST-ONE campaign, Atmos. Chem. Phys., 18, 12391–12411, https://doi.org/10.5194/acp-18-12391-2018, 2018.
Tan, Z., Lu, K., Hofzumahaus, A., Fuchs, H., Bohn, B., Holland, F., Liu, Y., Rohrer, F., Shao, M., Sun, K., Wu, Y., Zeng, L., Zhang, Y., Zou, Q., Kiendler-Scharr, A., Wahner, A., and Zhang, Y.: Experimental budgets of OH, HO2, and RO2 radicals and implications for ozone formation in the Pearl River Delta in China 2014, Atmos. Chem. Phys., 19, 7129–7150, https://doi.org/10.5194/acp-19-7129-2019, 2019.
Tanner, D. J., Jefferson, A., and Eisele, F. L.: Selected ion chemical
ionization mass spectrometric measurement of OH, J. Geophys. Res.-Atmos.,
102, 6415–6425, https://doi.org/10.1029/96jd03919, 1997.
Teng, A. P., Crounse, J. D., and Wennberg, P. O.: Isoprene peroxy radical
dynamics, J. Am. Chem. Soc., 139, 5367–5377, https://doi.org/10.1021/jacs.6b12838, 2017.
Wagner, N. L., Dubé, W. P., Washenfelder, R. A., Young, C. J., Pollack, I. B., Ryerson, T. B., and Brown, S. S.: Diode laser-based cavity ring-down instrument for NO3, N2O5, NO, NO2 and O3 from aircraft, Atmos. Meas. Tech., 4, 1227–1240, https://doi.org/10.5194/amt-4-1227-2011, 2011.
Wang, S., Riva, M., Yan, C., Ehn, M., and Wang, L.: Primary formation of
highly oxidized multifunctional products in the OH-initiated oxidation of
isoprene: A combined theoretical and experimental study, Environ. Sci.
Technol., 52, 12255–12264, https://doi.org/10.1021/acs.est.8b02783, 2018.
Whalley, L. K., Edwards, P. M., Furneaux, K. L., Goddard, A., Ingham, T., Evans, M. J., Stone, D., Hopkins, J. R., Jones, C. E., Karunaharan, A., Lee, J. D., Lewis, A. C., Monks, P. S., Moller, S. J., and Heard, D. E.: Quantifying the magnitude of a missing hydroxyl radical source in a tropical rainforest, Atmos. Chem. Phys., 11, 7223–7233, https://doi.org/10.5194/acp-11-7223-2011, 2011.
Whalley, L. K., Stone, D., Dunmore, R., Hamilton, J., Hopkins, J. R., Lee, J. D., Lewis, A. C., Williams, P., Kleffmann, J., Laufs, S., Woodward-Massey, R., and Heard, D. E.: Understanding in situ ozone production in the summertime through radical observations and modelling studies during the Clean air for London project (ClearfLo), Atmos. Chem. Phys., 18, 2547–2571, https://doi.org/10.5194/acp-18-2547-2018, 2018.
Wolfe, G. M., Crounse, J. D., Parrish, J. D., St. Clair, J. M., Beaver, M.
R., Paulot, F., Yoon, T. P., Wennberg, P. O., and Keutsch, F. N.:
Photolysis, OH reactivity and ozone reactivity of a proxy for
isoprene-derived hydroperoxyenals (HPALDs), Phys. Chem. Chem. Phys, 14,
7276–7286, https://doi.org/10.1039/C2CP40388A, 2012.
Wolfe, G. M., Cantrell, C., Kim, S., Mauldin III, R. L., Karl, T., Harley, P., Turnipseed, A., Zheng, W., Flocke, F., Apel, E. C., Hornbrook, R. S., Hall, S. R., Ullmann, K., Henry, S. B., DiGangi, J. P., Boyle, E. S., Kaser, L., Schnitzhofer, R., Hansel, A., Graus, M., Nakashima, Y., Kajii, Y., Guenther, A., and Keutsch, F. N.: Missing peroxy radical sources within a summertime ponderosa pine forest, Atmos. Chem. Phys., 14, 4715–4732, https://doi.org/10.5194/acp-14-4715-2014, 2014.
Woodward-Massey, R., Slater, E. J., Alen, J., Ingham, T., Cryer, D. R., Stimpson, L. M., Ye, C., Seakins, P. W., Whalley, L. K., and Heard, D. E.: Implementation of a chemical background method for atmospheric OH measurements by laser-induced fluorescence: characterisation and observations from the UK and China, Atmos. Meas. Tech., 13, 3119–3146, https://doi.org/10.5194/amt-13-3119-2020, 2020.
Zasypkin, A. Y., Grigor'eva, V. M., Korchak, V. N., and Gershenson, Y. M.: A
formula for summing of kinetic resistances for mobile and stationary media:
I. Cylindrical reactor, Kinet. Catal., 38, 772–781, 1997.
Short summary
This study describes the implementation and characterization of the chemical modulation reactor (CMR) used in the laser-induced fluorescence instrument of the Forschungszentrum Jülich. The CMR allows for interference-free OH radical measurement in ambient air. During a field campaign in a rural environment, the observed interference was mostly below the detection limit of the instrument and fully explained by the known ozone interference.
This study describes the implementation and characterization of the chemical modulation reactor...
