Articles | Volume 19, issue 6
https://doi.org/10.5194/amt-19-2047-2026
© Author(s) 2026. 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-19-2047-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
25 Mar 2026
Research article |
| 25 Mar 2026
| 25 Mar 2026
VOLCANO3 – a Miniaturized Chemiluminescence Ozone Monitor for Drone-Based Measurements in Volcanic Plumes
Maja Rüth
Institute of Environmental Physics, Heidelberg University, Heidelberg, Germany
now at: Institute for Atmospheric and Climate Science, ETH, Zurich, Switzerland
Nicole Bobrowski
CORRESPONDING AUTHOR
Institute of Environmental Physics, Heidelberg University, Heidelberg, Germany
Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Etneo, Catania, Italy
Ellen Bräutigam
Institute of Environmental Physics, Heidelberg University, Heidelberg, Germany
Alexander Nies
Laboratoire de Physique et Chimie de l'Environnement et de l'Espace, CNRS/University of Orléans, Orléans, France
Jonas Kuhn
Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, CA, USA
Thorsten Hoffmann
Institute of Inorganic and Analytical Chemistry, Johannes Gutenberg-University, Mainz, Germany
Niklas Karbach
Institute of Inorganic and Analytical Chemistry, Johannes Gutenberg-University, Mainz, Germany
Bastien Geil
Institute of Inorganic and Analytical Chemistry, Johannes Gutenberg-University, Mainz, Germany
Ralph Kleinschek
Institute of Environmental Physics, Heidelberg University, Heidelberg, Germany
Stefan Schmitt
Airyx GmbH, Hans-Bunte-Str. 4, 69123 Heidelberg, Germany
Ulrich Platt
Institute of Environmental Physics, Heidelberg University, Heidelberg, Germany
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Tobias Dieter Schmitt, Moritz Sindram, Benedikt Alexander Löw, Lukas Weis, Ralph Kleinschek, Nicole Bobrowski, and André Butz
EGUsphere, https://doi.org/10.5194/egusphere-2026-1387, https://doi.org/10.5194/egusphere-2026-1387, 2026
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
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Current monitoring systems for volcanic gases use ultra-violet and visible light, since the sky is bright in these regions. We analyzed if it is possible to extend their measurement concept to the near-infrared, where other important gases like CO2, HF and HCl are accessible. Our results indicate that this is unrealistic for CO2, but possible for HF and HCl, at least for some volcanos. In the future, this could contribute to a better understanding of volcanic processes and eruption risks.
Jochen Stutz, Jonas Kuhn, Sol Cooperdock, Sarah Johnson, Fangzhou Guo, James H. Flynn, Meeta Cesler-Maloney, and William R. Simpson
EGUsphere, https://doi.org/10.5194/egusphere-2026-816, https://doi.org/10.5194/egusphere-2026-816, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Northern cities often experience periods of wintertime air pollution, which are associated with surface temperature inversions and weak winds. In Fairbanks, Alaska, pollutants accumulate in a 20–40 m high surface layer with SO2 and NO2 mixing ratios of up to 35 ppb and 65 ppb, respectively. This surface pollution is caused by the balance of emissions, chemistry, and inefficient mixing with clean background air. This balance has to be considered for air pollution mitigation strategies.
Patrick Dewald, Tobias Seubert, Laura Wüst, Jan Schuladen, Frank Drewnick, Friederike Fachinger, Thorsten Hoffmann, and John N. Crowley
EGUsphere, https://doi.org/10.5194/egusphere-2026-157, https://doi.org/10.5194/egusphere-2026-157, 2026
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
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We have developed and tested an instrument that quantitatively detects particulate nitrate. Gas-phase reactive nitrogen species are denuded using an active-carbon surface and particle nitrate is converted to NO2, which is detected using cavity-ringdown-spectroscopy. Key to accurate measurement of particulate nitrate is drying of the sampled air. Excellent agreement with an aerosol-mass-spectrometer indicates that the instrument detects both organic and inorganic nitrate particle mass accurately.
Denis Leppla, Stefanie Hildmann, Nora Zannoni, Leslie A. Kremper, Bruna A. Holanda, Jonathan Williams, Christopher Pöhlker, Stefan Wolff, Marta Sà, Maria Christina Solci, Ulrich Pöschl, and Thorsten Hoffmann
Atmos. Chem. Phys., 26, 365–390, https://doi.org/10.5194/acp-26-365-2026, https://doi.org/10.5194/acp-26-365-2026, 2026
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The chemical composition of organic particles in the Amazon rainforest was investigated to understand how biogenic and human emissions influence the atmosphere in this unique ecosystem. Seasonal patterns were found where wet seasons were dominated by biogenic compounds from natural sources while dry seasons showed increased fire-related pollutants. These findings reveal how emissions, fires and long-range transport affect atmospheric chemistry, with implications for climate models.
Jackson Seymore, Miklós Szakáll, Alexander Theis, Subir K. Mitra, Christine Borchers, and Thorsten Hoffmann
Atmos. Chem. Phys., 25, 18249–18265, https://doi.org/10.5194/acp-25-18249-2025, https://doi.org/10.5194/acp-25-18249-2025, 2025
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Laboratory studies examined carbonyl deposition into ice crystals using a flowtube setup. Ice crystals were grown under conditions that mimic cirrus clouds in the presence of carbonyl vapors. Ice and gas samples were collected and analyzed to calculate ice uptake coefficients for 14 carbonyls at different temperatures. This revealed an inverse relationship between uptake and temperature. Vapor pressure and molar mass were found to be the most significant factors in uptake.
Thomas Wagner, Steffen Beirle, Sebastian Donner, Carl-Fredrik Enell, Myojeong Gu, Bianca Lauster, Ulrich Platt, Janis Pukite, Uwe Raffalski, and Steffen Ziegler
EGUsphere, https://doi.org/10.5194/egusphere-2025-5878, https://doi.org/10.5194/egusphere-2025-5878, 2025
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The characterisation of spectroscopic properties of Differential Optical Absorption Spectroscopy (DOAS) instruments is important for accurate trace gas retrievals. In this study, we evaluate and extend existing methods for the determination of such properties using high-resolution solar spectra. These methods can be applied to routine observations in the field. Our results and developed techniques are especially important for trend analyses from long-term measurements.
Christine Borchers, Lasse Moormann, Bastien Geil, Niklas Karbach, David Wasserzier, and Thorsten Hoffmann
Atmos. Meas. Tech., 18, 7231–7242, https://doi.org/10.5194/amt-18-7231-2025, https://doi.org/10.5194/amt-18-7231-2025, 2025
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A three-dimensionally printed filter holder is connected to a lightweight, high-performance pump. This sampling system allows for easy and cost-effective measurements of organic aerosols at different heights and locations. By elucidating the chemical composition of organic aerosol, sources and processing of the compounds can be identified. Measurements at different altitudes and times of the day provide insight into the chemical aging and daytime trends of the aerosol particles.
Anna Breuninger, Philipp Joppe, Jonas Wilsch, Cornelis Schwenk, Heiko Bozem, Nicolas Emig, Laurin Merkel, Rainer Rossberg, Timo Keber, Arthur Kutschka, Philipp Waleska, Stefan Hofmann, Sarah Richter, Florian Ungeheuer, Konstantin Dörholt, Thorsten Hoffmann, Annette Miltenberger, Johannes Schneider, Peter Hoor, and Alexander L. Vogel
Atmos. Chem. Phys., 25, 16533–16551, https://doi.org/10.5194/acp-25-16533-2025, https://doi.org/10.5194/acp-25-16533-2025, 2025
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This study investigates molecular organic aerosol composition in the upper troposphere and lower stratosphere from an airborne campaign over Central Europe in summer 2024. Via ultra-high-performance liquid chromatography and high-resolution mass spectrometry of tropospheric and stratospheric filter samples, we identified various organic compounds. Our findings underscore the significant cross-tropopause transport of biogenic secondary organic aerosol and anthropogenic pollutants.
Jackson Seymore, Martanda Gautam, Miklós Szakáll, Alexander Theis, Thorsten Hoffmann, Jialiang Ma, Lingli Zhou, and Alexander L. Vogel
Atmos. Chem. Phys., 25, 11829–11845, https://doi.org/10.5194/acp-25-11829-2025, https://doi.org/10.5194/acp-25-11829-2025, 2025
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We investigated the chemical retention of water-soluble organic compounds in Beijing aerosols using an acoustic levitator and drop-freezing experiments. Samples from PM2.5 filter extracts were frozen at -15 °C in an acoustic levitator without artificial nucleators and analyzed using ultra-high resolution mass spectrometry. Our findings reveal a non-normal distribution of retention coefficients that differs from current literature on cloud droplets.
Vincent Enders, Astrid Müller, Matthias Max Frey, Frank Hase, Ralph Kleinschek, Marvin Knapp, Benedikt Löw, Isamu Morino, Shin-Ichiro Nakaoka, Hideki Nara, Hiroshi Tanimoto, Sanam N. Vardag, Karolin Voss, and André Butz
EGUsphere, https://doi.org/10.5194/egusphere-2025-4552, https://doi.org/10.5194/egusphere-2025-4552, 2025
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We have deployed two spectrometers on a ship traveling along the coast of Japan. By that, we were able to repeatedly measure the greenhouse gas and air pollutant emissions of power plants, large industrial facilities, and cities. Using the ratios between the different gases, we are able to identify sources based on their unique signature. In addition, we are able to show that spectrometers can be operated on a ship, while still fulfilling the high standards of land-based observation networks.
Bianca Lauster, Udo Frieß, Jan-Marcus Nasse, Ulrich Platt, and Thomas Wagner
Atmos. Meas. Tech., 18, 3393–3405, https://doi.org/10.5194/amt-18-3393-2025, https://doi.org/10.5194/amt-18-3393-2025, 2025
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Remote sensing measurements of scattered sunlight use the atmospheric absorption of O2–O2 (or O4) to derive cloud and aerosol properties. However, inconsistencies between measurements and radiative transfer simulations were found recently, and, so far, there has been no consensus on how to deal with these appropriately. In this study, long-term long-path differential optical absorption spectroscopy (LP-DOAS) observations were analysed and very good agreement with laboratory measurements was found.
Jade Margerum, Julia Homann, Stuart Umbo, Gernot Nehrke, Thorsten Hoffmann, Anton Vaks, Aleksandr Kononov, Alexander Osintsev, Alena Giesche, Andrew Mason, Franziska A. Lechleitner, Gideon M. Henderson, Ola Kwiecien, and Sebastian F. M. Breitenbach
Clim. Past, 21, 661–677, https://doi.org/10.5194/cp-21-661-2025, https://doi.org/10.5194/cp-21-661-2025, 2025
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We analyse a southern Siberian stalagmite to reconstruct soil respiration, wildfire, and vegetation trends during the Last Interglacial (LIG) (124.1–118.8 ka) and the Holocene (10–0 ka). Wildfires were more prevalent during the LIG than the Holocene and were supported by fire-prone species, low soil respiration, and a greater difference between summer and winter temperature. We show that vegetation type and summer/winter temperature contrast are strong drivers of Siberian wildfires.
Johanna Schäfer, Anja Beschnitt, François Burgay, Thomas Singer, Margit Schwikowski, and Thorsten Hoffmann
Atmos. Meas. Tech., 18, 421–430, https://doi.org/10.5194/amt-18-421-2025, https://doi.org/10.5194/amt-18-421-2025, 2025
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Glaciers preserve organic compounds from atmospheric aerosols, which can serve as markers for emission sources. Most studies overlook the enantiomers of chiral compounds. We developed a two-dimensional liquid chromatography method to determine the chiral ratios of the monoterpene oxidation products cis-pinic acid and cis-pinonic acid in ice-core samples. Applied to samples from the Belukha Glacier (1870–1970 CE), the method revealed fluctuating chiral ratios for the analytes.
Christine Borchers, Jackson Seymore, Martanda Gautam, Konstantin Dörholt, Yannik Müller, Andreas Arndt, Laura Gömmer, Florian Ungeheuer, Miklós Szakáll, Stephan Borrmann, Alexander Theis, Alexander L. Vogel, and Thorsten Hoffmann
Atmos. Chem. Phys., 24, 13961–13974, https://doi.org/10.5194/acp-24-13961-2024, https://doi.org/10.5194/acp-24-13961-2024, 2024
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Riming, a crucial process in cloud dynamics, influences the vertical distribution of compounds in the atmosphere. Experiments in Mainz's wind tunnel investigated retention coefficients of organic compounds under varying conditions. Findings suggest a correlation between the Henry's law constant and retention, applicable even to complex organic molecules.
Karolin Voss, Philip Holzbeck, Klaus Pfeilsticker, Ralph Kleinschek, Gerald Wetzel, Blanca Fuentes Andrade, Michael Höpfner, Jörn Ungermann, Björn-Martin Sinnhuber, and André Butz
Atmos. Meas. Tech., 17, 4507–4528, https://doi.org/10.5194/amt-17-4507-2024, https://doi.org/10.5194/amt-17-4507-2024, 2024
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A novel balloon-borne instrument for direct sun and solar occultation measurements of several UV–Vis absorbing gases (e.g. O3, NO2, BrO, IO, and HONO) is described. Its major design features and performance during two stratospheric deployments are discussed. From the measured overhead BrO concentration and a suitable photochemical correction, total stratospheric bromine is inferred to (17.5 ± 2.2) ppt in air masses which entered the stratosphere around early 2017 ± 1 year.
Niklas Karbach, Lisa Höhler, Peter Hoor, Heiko Bozem, Nicole Bobrowski, and Thorsten Hoffmann
Atmos. Meas. Tech., 17, 4081–4086, https://doi.org/10.5194/amt-17-4081-2024, https://doi.org/10.5194/amt-17-4081-2024, 2024
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The system presented here can accurately generate and reproduce a stable flow of gas mixtures of known concentrations over several days using ambient air as a dilution medium. In combination with the small size and low weight of the system, this enables the calibration of hydrogen sensors in the field, reducing the influence of matrix effects on the accuracy of the sensor. The system is inexpensive to assemble and easy to maintain, which is the key to reliable measurement results.
Meeta Cesler-Maloney, William Simpson, Jonas Kuhn, Jochen Stutz, Jennie Thomas, Tjarda Roberts, Deanna Huff, and Sol Cooperdock
EGUsphere, https://doi.org/10.5194/egusphere-2023-3082, https://doi.org/10.5194/egusphere-2023-3082, 2024
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We used a one-dimensional model to simulate how pollution in Fairbanks, Alaska, accumulates in shallow layers near the ground when temperature inversions are present. We find pollution accumulates in a 20 m to 50 m thick layer. The model agrees with observations of SO2 pollution using only home heating emissions sources, which shows that ground-based sources dominate sulfur pollution in downtown Fairbanks. Air residence times in downtown are only a few hours, limiting chemical transformations.
Tobias D. Schmitt, Jonas Kuhn, Ralph Kleinschek, Benedikt A. Löw, Stefan Schmitt, William Cranton, Martina Schmidt, Sanam N. Vardag, Frank Hase, David W. T. Griffith, and André Butz
Atmos. Meas. Tech., 16, 6097–6110, https://doi.org/10.5194/amt-16-6097-2023, https://doi.org/10.5194/amt-16-6097-2023, 2023
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Our new observatory measures greenhouse gas concentrations of carbon dioxide (CO2) and methane (CH4) along a 1.55 km long light path over the city of Heidelberg, Germany. We compared our measurements with measurements that were taken at a single point at one end of our path. The two mostly agreed but show a significant difference for CO2 with certain wind directions. This is important when using greenhouse gas concentration measurements to observe greenhouse gas emissions of cities.
Simon Warnach, Holger Sihler, Christian Borger, Nicole Bobrowski, Steffen Beirle, Ulrich Platt, and Thomas Wagner
Atmos. Meas. Tech., 16, 5537–5573, https://doi.org/10.5194/amt-16-5537-2023, https://doi.org/10.5194/amt-16-5537-2023, 2023
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BrO inside volcanic gas plumes but can be used in combination with SO2 to characterize the volcanic property and its activity state. High-quality satellite observations can provide a global inventory of this important quantity. This paper investigates how to accurately detect BrO inside volcanic plumes from the satellite UV spectrum. A sophisticated novel non-volcanic background correction scheme is presented, and systematic errors including cross-interference with formaldehyde are minimized.
Julia Homann, Niklas Karbach, Stacy A. Carolin, Daniel H. James, David Hodell, Sebastian F. M. Breitenbach, Ola Kwiecien, Mark Brenner, Carlos Peraza Lope, and Thorsten Hoffmann
Biogeosciences, 20, 3249–3260, https://doi.org/10.5194/bg-20-3249-2023, https://doi.org/10.5194/bg-20-3249-2023, 2023
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Cave stalagmites contain substances that can be used to reconstruct past changes in local and regional environmental conditions. We used two classes of biomarkers (polycyclic aromatic hydrocarbons and monosaccharide anhydrides) to detect the presence of fire and to also explore changes in fire regime (e.g. fire frequency, intensity, and fuel source). We tested our new method on a stalagmite from Mayapan, a large Maya city on the Yucatán Peninsula.
Thomas Wagner, Simon Warnach, Steffen Beirle, Nicole Bobrowski, Adrian Jost, Janis Puķīte, and Nicolas Theys
Atmos. Meas. Tech., 16, 1609–1662, https://doi.org/10.5194/amt-16-1609-2023, https://doi.org/10.5194/amt-16-1609-2023, 2023
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We investigate 3D effects of volcanic plumes on the retrieval results of satellite and ground-based UV–Vis observations. With its small ground pixels of 3.5 x 5.5 km², the TROPOMI instrument can detect much smaller volcanic plumes than previous instruments. At the same time, 3D effects become important. The effect of horizontal photon paths especially can lead to a strong underestimation of the derived plume contents of up to > 50 %, which can be further increased for strong absorbers like SO2.
Henning Finkenzeller, Denis Pöhler, Martin Horbanski, Johannes Lampel, and Ulrich Platt
Atmos. Meas. Tech., 16, 1343–1356, https://doi.org/10.5194/amt-16-1343-2023, https://doi.org/10.5194/amt-16-1343-2023, 2023
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Optical resonators enhance the light path in compact instruments, thereby improving their sensitivity. Determining the established path length in the instrument is a prerequisite for the accurate determination of trace gas concentrations but can be a significant complication in the use of such resonators. Here we show two calibration techniques which are relatively simple and free of consumables but still provide accurate calibrations. This facilitates the use of optical resonators.
Udo Frieß, Karin Kreher, Richard Querel, Holger Schmithüsen, Dan Smale, Rolf Weller, and Ulrich Platt
Atmos. Chem. Phys., 23, 3207–3232, https://doi.org/10.5194/acp-23-3207-2023, https://doi.org/10.5194/acp-23-3207-2023, 2023
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Reactive bromine compounds, emitted by the sea ice during polar spring, play an important role in the atmospheric chemistry of the coastal regions of Antarctica. We investigate the sources and impacts of reactive bromine in detail using many years of measurements at two Antarctic sites located at opposite sides of the Antarctic continent. Using a multitude of meteorological observations, we were able to identify the main triggers and source regions for reactive bromine in Antarctica.
Denis Leppla, Nora Zannoni, Leslie Kremper, Jonathan Williams, Christopher Pöhlker, Marta Sá, Maria Christina Solci, and Thorsten Hoffmann
Atmos. Chem. Phys., 23, 809–820, https://doi.org/10.5194/acp-23-809-2023, https://doi.org/10.5194/acp-23-809-2023, 2023
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Chiral chemodiversity plays a critical role in biochemical processes such as insect and plant communication. Here we report on the measurement of chiral-specified secondary organic aerosol in the Amazon rainforest. The results show that the chiral ratio is mainly determined by large-scale emission processes. Characteristic emissions of chiral aerosol precursors from different forest ecosystems can thus provide large-scale information on different biogenic sources via chiral particle analysis.
Yunfan Liu, Hang Su, Siwen Wang, Chao Wei, Wei Tao, Mira L. Pöhlker, Christopher Pöhlker, Bruna A. Holanda, Ovid O. Krüger, Thorsten Hoffmann, Manfred Wendisch, Paulo Artaxo, Ulrich Pöschl, Meinrat O. Andreae, and Yafang Cheng
Atmos. Chem. Phys., 23, 251–272, https://doi.org/10.5194/acp-23-251-2023, https://doi.org/10.5194/acp-23-251-2023, 2023
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The origins of the abundant cloud condensation nuclei (CCN) in the upper troposphere (UT) of the Amazon remain unclear. With model developments of new secondary organic aerosol schemes and constrained by observation, we show that strong aerosol nucleation and condensation in the UT is triggered by biogenic organics, and organic condensation is key for UT CCN production. This UT CCN-producing mechanism may prevail over broader vegetation canopies and deserves emphasis in aerosol–climate feedback.
Maximilian Herrmann, Moritz Schöne, Christian Borger, Simon Warnach, Thomas Wagner, Ulrich Platt, and Eva Gutheil
Atmos. Chem. Phys., 22, 13495–13526, https://doi.org/10.5194/acp-22-13495-2022, https://doi.org/10.5194/acp-22-13495-2022, 2022
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Ozone depletion events (ODEs) are a common occurrence in the boundary layer during Arctic spring. Ozone is depleted by bromine species in an autocatalytic reaction cycle. Previous modeling studies assumed an infinite bromine source at the ground. An alternative emission scheme is presented in which a finite amount of bromide in the snow is tracked over time. The Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) is used to study ODEs in the Arctic from February to May 2019.
Jing Duan, Ru-Jin Huang, Yifang Gu, Chunshui Lin, Haobin Zhong, Wei Xu, Quan Liu, Yan You, Jurgita Ovadnevaite, Darius Ceburnis, Thorsten Hoffmann, and Colin O'Dowd
Atmos. Chem. Phys., 22, 10139–10153, https://doi.org/10.5194/acp-22-10139-2022, https://doi.org/10.5194/acp-22-10139-2022, 2022
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Biomass-burning-influenced oxygenated organic aerosol (OOA-BB), formed from the photochemical oxidation and aging of biomass burning OA (BBOA), was resolved in urban Xi’an. The aqueous-phase processed oxygenated OA (aq-OOA) concentration was more dependent on secondary inorganic aerosol (SIA) content and aerosol liquid water content (ALWC). The increased aq-OOA contribution during SIA-enhanced periods likely reflects OA evolution due to the addition of alcohol or peroxide groups
M. Dolores Andrés Hernández, Andreas Hilboll, Helmut Ziereis, Eric Förster, Ovid O. Krüger, Katharina Kaiser, Johannes Schneider, Francesca Barnaba, Mihalis Vrekoussis, Jörg Schmidt, Heidi Huntrieser, Anne-Marlene Blechschmidt, Midhun George, Vladyslav Nenakhov, Theresa Harlass, Bruna A. Holanda, Jennifer Wolf, Lisa Eirenschmalz, Marc Krebsbach, Mira L. Pöhlker, Anna B. Kalisz Hedegaard, Linlu Mei, Klaus Pfeilsticker, Yangzhuoran Liu, Ralf Koppmann, Hans Schlager, Birger Bohn, Ulrich Schumann, Andreas Richter, Benjamin Schreiner, Daniel Sauer, Robert Baumann, Mariano Mertens, Patrick Jöckel, Markus Kilian, Greta Stratmann, Christopher Pöhlker, Monica Campanelli, Marco Pandolfi, Michael Sicard, José L. Gómez-Amo, Manuel Pujadas, Katja Bigge, Flora Kluge, Anja Schwarz, Nikos Daskalakis, David Walter, Andreas Zahn, Ulrich Pöschl, Harald Bönisch, Stephan Borrmann, Ulrich Platt, and John P. Burrows
Atmos. Chem. Phys., 22, 5877–5924, https://doi.org/10.5194/acp-22-5877-2022, https://doi.org/10.5194/acp-22-5877-2022, 2022
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EMeRGe provides a unique set of in situ and remote sensing airborne measurements of trace gases and aerosol particles along selected flight routes in the lower troposphere over Europe. The interpretation uses also complementary collocated ground-based and satellite measurements. The collected data help to improve the current understanding of the complex spatial distribution of trace gases and aerosol particles resulting from mixing, transport, and transformation of pollution plumes over Europe.
Jan-Lukas Tirpitz, Udo Frieß, Robert Spurr, and Ulrich Platt
Atmos. Meas. Tech., 15, 2077–2098, https://doi.org/10.5194/amt-15-2077-2022, https://doi.org/10.5194/amt-15-2077-2022, 2022
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MAX-DOAS is a widely used measurement technique for the remote detection of atmospheric aerosol and trace gases. It relies on the analysis of ultra-violet and visible radiation spectra of skylight. To date, information contained in the skylight's polarisation state has not been utilised. On the basis of synthetic data, we carried out sensitivity analyses to assess the potential of polarimetry for MAX-DOAS applications.
Leon Kuhn, Jonas Kuhn, Thomas Wagner, and Ulrich Platt
Atmos. Meas. Tech., 15, 1395–1414, https://doi.org/10.5194/amt-15-1395-2022, https://doi.org/10.5194/amt-15-1395-2022, 2022
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We present a novel instrument for imaging measurements of NO2 with high spatiotemporal resolution based on gas correlation spectroscopy, called the GCS NO2 camera. The instrument works by placing two gas cells (cuvettes) in front of two photosensor arrays, one filled with air and one filled with a high concentration of NO2, acting as a non-dispersive spectral filter. NO2 images are then generated on the basis of the signal ratio of the two channels in the spectral region of 430–445 nm.
Jonas Kuhn, Nicole Bobrowski, Thomas Wagner, and Ulrich Platt
Atmos. Meas. Tech., 14, 7873–7892, https://doi.org/10.5194/amt-14-7873-2021, https://doi.org/10.5194/amt-14-7873-2021, 2021
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We propose spectrograph implementations using Fabry–Pérot interferometers for atmospheric trace gas remote sensing. Compared with widely used grating spectrographs, we find substantial light throughput and mobility advantages for high resolving powers. Besides lowering detection limits and increasing the spatial and temporal resolution of many atmospheric trace gas measurements, this approach might enable remote sensing of further important gases such as tropospheric OH radicals.
Ulrich Platt, Thomas Wagner, Jonas Kuhn, and Thomas Leisner
Atmos. Meas. Tech., 14, 6867–6883, https://doi.org/10.5194/amt-14-6867-2021, https://doi.org/10.5194/amt-14-6867-2021, 2021
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Absorption spectroscopy of scattered sunlight is extremely useful for the analysis of atmospheric trace gas distributions. A central parameter for the achievable sensitivity of spectroscopic instruments is the light throughput, which can be enhanced in a number of ways. We present new ideas and considerations of how instruments could be optimized. Particular emphasis is on arrays of massively parallel instruments. Such arrays can reduce the size and weight of instruments by orders of magnitude.
Alexandra Gutmann, Nicole Bobrowski, Marcello Liotta, and Thorsten Hoffmann
Atmos. Meas. Tech., 14, 6395–6406, https://doi.org/10.5194/amt-14-6395-2021, https://doi.org/10.5194/amt-14-6395-2021, 2021
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Motivated by a special interest in bromine chemistry in volcanic plumes, the study presented here describes a new method for the quantitative collection of gaseous hydrogen bromide in gas diffusion denuders. The hydrogen bromide reacted during sampling with appropriate epoxides applied to the denuder walls. The denuder sampling assembly was successfully deployed in the volcanic plume of Masaya volcano, Nicaragua.
Kai Krause, Folkard Wittrock, Andreas Richter, Stefan Schmitt, Denis Pöhler, Andreas Weigelt, and John P. Burrows
Atmos. Meas. Tech., 14, 5791–5807, https://doi.org/10.5194/amt-14-5791-2021, https://doi.org/10.5194/amt-14-5791-2021, 2021
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Ships are an important source of key pollutants. Usually, these are measured aboard the ship or on the coast using in situ instruments. This study shows how active optical remote sensing can be used to measure ship emissions and how to determine emission rates of individual ships out of those measurements. These emission rates are valuable input for the assessment of the influence of shipping emissions in regions close to the shipping lanes.
Haijie Tong, Fobang Liu, Alexander Filippi, Jake Wilson, Andrea M. Arangio, Yun Zhang, Siyao Yue, Steven Lelieveld, Fangxia Shen, Helmi-Marja K. Keskinen, Jing Li, Haoxuan Chen, Ting Zhang, Thorsten Hoffmann, Pingqing Fu, William H. Brune, Tuukka Petäjä, Markku Kulmala, Maosheng Yao, Thomas Berkemeier, Manabu Shiraiwa, and Ulrich Pöschl
Atmos. Chem. Phys., 21, 10439–10455, https://doi.org/10.5194/acp-21-10439-2021, https://doi.org/10.5194/acp-21-10439-2021, 2021
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We measured radical yields of aqueous PM2.5 extracts and found lower yields at higher concentrations of PM2.5. Abundances of water-soluble transition metals and aromatics in PM2.5 were positively correlated with the relative fraction of •OH but negatively correlated with the relative fraction of C-centered radicals among detected radicals. Composition-dependent reactive species yields may explain differences in the reactivity and health effects of PM2.5 in clean versus polluted air.
Florian Dinger, Timo Kleinbek, Steffen Dörner, Nicole Bobrowski, Ulrich Platt, Thomas Wagner, Martha Ibarra, and Eveling Espinoza
Atmos. Chem. Phys., 21, 9367–9404, https://doi.org/10.5194/acp-21-9367-2021, https://doi.org/10.5194/acp-21-9367-2021, 2021
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Monitoring magnitude or chemical composition of volcanic gas emissions can help to forecast volcanic eruptions and provides empirical data on the impact of volcanoes on the chemistry in the local and global atmosphere. This study reports and discusses continuous time series of the sulfur and bromine emission fluxes of Masaya from 2014 to 2020. We observed an annual cyclicity in the BrO / SO2 molar ratio, possibly caused by the annual variability in the atmospheric humidity.
Kai Wang, Ru-Jin Huang, Martin Brüggemann, Yun Zhang, Lu Yang, Haiyan Ni, Jie Guo, Meng Wang, Jiajun Han, Merete Bilde, Marianne Glasius, and Thorsten Hoffmann
Atmos. Chem. Phys., 21, 9089–9104, https://doi.org/10.5194/acp-21-9089-2021, https://doi.org/10.5194/acp-21-9089-2021, 2021
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Here we present the detailed molecular composition of the organic aerosol collected in three eastern Chinese cities from north to south, Changchun, Shanghai and Guangzhou, by applying LC–Orbitrap analysis. Accordingly, the aromaticity degree of chemical compounds decreases from north to south, while the oxidation degree increases from north to south, which can be explained by the different anthropogenic emissions and photochemical oxidation processes.
Bo Galle, Santiago Arellano, Nicole Bobrowski, Vladimir Conde, Tobias P. Fischer, Gustav Gerdes, Alexandra Gutmann, Thorsten Hoffmann, Ima Itikarai, Tomas Krejci, Emma J. Liu, Kila Mulina, Scott Nowicki, Tom Richardson, Julian Rüdiger, Kieran Wood, and Jiazhi Xu
Atmos. Meas. Tech., 14, 4255–4277, https://doi.org/10.5194/amt-14-4255-2021, https://doi.org/10.5194/amt-14-4255-2021, 2021
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Measurements of volcanic gases are important for geophysical research, risk assessment and environmental impact studies. Some gases, like SO2 and BrO, may be studied from the ground at a safe distance using remote sensing techniques. Many other gases require in situ access to the gas plume. Here, a drone may be an attractive alternative. This paper describes a drone specially adapted for volcanic gas studies and demonstrates its use in a field campaign at Manam volcano in Papua New Guinea.
Maximilian Herrmann, Holger Sihler, Udo Frieß, Thomas Wagner, Ulrich Platt, and Eva Gutheil
Atmos. Chem. Phys., 21, 7611–7638, https://doi.org/10.5194/acp-21-7611-2021, https://doi.org/10.5194/acp-21-7611-2021, 2021
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Time-dependent 3D numerical simulations of tropospheric bromine release and ozone depletion events (ODEs) in the Arctic polar spring of 2009 are compared to observations. Simulation results agree well with the observations at both Utqiaġvik, Alaska, and at Summit, Greenland. In a parameter study, different settings for the bromine release mechanism are evaluated. An enhancement of the bromine release mechanism improves the agreement regarding the occurrence of ODEs with the observations.
Inken Heidke, Adam Hartland, Denis Scholz, Andrew Pearson, John Hellstrom, Sebastian F. M. Breitenbach, and Thorsten Hoffmann
Biogeosciences, 18, 2289–2300, https://doi.org/10.5194/bg-18-2289-2021, https://doi.org/10.5194/bg-18-2289-2021, 2021
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We analyzed lignin oxidation products (LOPs) in leaf litter and different soil horizons as well as dripwater and flowstone samples from four different cave sites from different vegetation zones in New Zealand using liquid chromatography coupled to mass spectrometry. We test whether the original source-dependent LOP signal of the overlying vegetation is preserved and can be recovered from flowstone samples and investigate how the signal is altered by the transport from the soil to the cave.
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Short summary
UV absorption and electrochemical O3 sensor measurement techniques suffer from interferences, especially from SO2, which is a main constituent of volcanic plumes. Only chemiluminescence (CL) O3 monitors have no known interference with SO2. However, modern CL O3 monitors are impractical because they are heavy and bulky. We developed and applied a lightweight version of a CL O3 instrument (l.5 kg, shoebox size) and present the result of those drone based CL O3 measurements.
UV absorption and electrochemical O3 sensor measurement techniques suffer from interferences,...
