Articles | Volume 18, issue 3
https://doi.org/10.5194/acp-18-1671-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-18-1671-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
06 Feb 2018
Research article |
| 06 Feb 2018
| 06 Feb 2018
Detection of O4 absorption around 328 and 419 nm in measured atmospheric absorption spectra
Johannes Lampel
CORRESPONDING AUTHOR
Max Planck Institute for Chemistry, Mainz, Germany
now at: Institute of Environmental Physics, University of Heidelberg, Heidelberg, Germany
Johannes Zielcke
Institute of Environmental Physics, University of Heidelberg, Heidelberg, Germany
now at: Faculty of Medicine, University of Heidelberg, Heidelberg, Germany
Stefan Schmitt
Institute of Environmental Physics, University of Heidelberg, Heidelberg, Germany
Denis Pöhler
Institute of Environmental Physics, University of Heidelberg, Heidelberg, Germany
Udo Frieß
Institute of Environmental Physics, University of Heidelberg, Heidelberg, Germany
Ulrich Platt
Institute of Environmental Physics, University of Heidelberg, Heidelberg, Germany
Thomas Wagner
Max Planck Institute for Chemistry, Mainz, Germany
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Thomas Wagner, Steffen Beirle, Nuria Benavent, Tim Bösch, Ka Lok Chan, Sebastian Donner, Steffen Dörner, Caroline Fayt, Udo Frieß, David García-Nieto, Clio Gielen, David González-Bartolome, Laura Gomez, François Hendrick, Bas Henzing, Jun Li Jin, Johannes Lampel, Jianzhong Ma, Kornelia Mies, Mónica Navarro, Enno Peters, Gaia Pinardi, Olga Puentedura, Janis Puķīte, Julia Remmers, Andreas Richter, Alfonso Saiz-Lopez, Reza Shaiganfar, Holger Sihler, Michel Van Roozendael, Yang Wang, and Margarita Yela
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Yang Wang, Steffen Beirle, Johannes Lampel, Mariliza Koukouli, Isabelle De Smedt, Nicolas Theys, Ang Li, Dexia Wu, Pinhua Xie, Cheng Liu, Michel Van Roozendael, Trissevgeni Stavrakou, Jean-François Müller, and Thomas Wagner
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Enno Peters, Gaia Pinardi, André Seyler, Andreas Richter, Folkard Wittrock, Tim Bösch, Michel Van Roozendael, François Hendrick, Theano Drosoglou, Alkiviadis F. Bais, Yugo Kanaya, Xiaoyi Zhao, Kimberly Strong, Johannes Lampel, Rainer Volkamer, Theodore Koenig, Ivan Ortega, Olga Puentedura, Mónica Navarro-Comas, Laura Gómez, Margarita Yela González, Ankie Piters, Julia Remmers, Yang Wang, Thomas Wagner, Shanshan Wang, Alfonso Saiz-Lopez, David García-Nieto, Carlos A. Cuevas, Nuria Benavent, Richard Querel, Paul Johnston, Oleg Postylyakov, Alexander Borovski, Alexander Elokhov, Ilya Bruchkouski, Haoran Liu, Cheng Liu, Qianqian Hong, Claudia Rivera, Michel Grutter, Wolfgang Stremme, M. Fahim Khokhar, Junaid Khayyam, and John P. Burrows
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This work is about harmonization of differential optical absorption spectroscopy retrieval codes, which is a remote sensing technique widely used to derive atmospheric trace gas amounts. The study is based on ground-based measurements performed during the Multi-Axis DOAS Comparison campaign for Aerosols and Trace gases (MAD-CAT) in Mainz, Germany, in summer 2013. In total, 17 international groups working in the field of the DOAS technique participated in this study.
Holger Sihler, Peter Lübcke, Rüdiger Lang, Steffen Beirle, Martin de Graaf, Christoph Hörmann, Johannes Lampel, Marloes Penning de Vries, Julia Remmers, Ed Trollope, Yang Wang, and Thomas Wagner
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Steffen Beirle, Johannes Lampel, Christophe Lerot, Holger Sihler, and Thomas Wagner
Atmos. Meas. Tech., 10, 581–598, https://doi.org/10.5194/amt-10-581-2017, https://doi.org/10.5194/amt-10-581-2017, 2017
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We propose to parameterize the instrumental spectral response function (ISRF) as a "super-Gaussian", which can reproduce a variety of shapes, from point-hat to boxcar shape, by just adding one parameter to the "classical" Gaussian.
In addition, the super-Gaussian allows for a straightforward parametrization of the effect of ISRF changes.
Yang Wang, Johannes Lampel, Pinhua Xie, Steffen Beirle, Ang Li, Dexia Wu, and Thomas Wagner
Atmos. Chem. Phys., 17, 2189–2215, https://doi.org/10.5194/acp-17-2189-2017, https://doi.org/10.5194/acp-17-2189-2017, 2017
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The air pollution in the Yangtze River delta (YRD), the largest economic region in China, threatens the health of the inhabitants in this region. A long-term MAX-DOAS observation in Wuxi, China (belonging to YRD), is used to characterize vertical distributions (VD) of the aerosols and the precursor trace gases in the boundary to identify the dominating sources. The results are valuable for further validation of satellite products and chemical transport modelings.
Johannes Lampel, Denis Pöhler, Oleg L. Polyansky, Aleksandra A. Kyuberis, Nikolai F. Zobov, Jonathan Tennyson, Lorenzo Lodi, Udo Frieß, Yang Wang, Steffen Beirle, Ulrich Platt, and Thomas Wagner
Atmos. Chem. Phys., 17, 1271–1295, https://doi.org/10.5194/acp-17-1271-2017, https://doi.org/10.5194/acp-17-1271-2017, 2017
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Water vapour is known to absorb radiation from the microwave region to the blue part of the visible spectrum.
Ab initio approaches to model individual absorption lines of the gaseous water molecule predict absorption lines
until its dissociation limit at 243 nm.
We present first evidence of water vapour absorption near 363 nm from field measurements using data
from multi-axis differential optical absorption spectroscopy (MAX-DOAS) and long-path (LP)-DOAS measurements.
Peter Lübcke, Johannes Lampel, Santiago Arellano, Nicole Bobrowski, Florian Dinger, Bo Galle, Gustavo Garzón, Silvana Hidalgo, Zoraida Chacón Ortiz, Leif Vogel, Simon Warnach, and Ulrich Platt
Atmos. Meas. Tech., 9, 5677–5698, https://doi.org/10.5194/amt-9-5677-2016, https://doi.org/10.5194/amt-9-5677-2016, 2016
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We evaluated spectra from a scanning spectrometer network for the monitoring of volcanic gas emissions using a modelled background spectrum. Statistical methods were applied in order to improve the quality of the spectroscopic evaluation. We used this technique to assess the robustness of standard retrievals at two volcanos: Nevado del Ruiz (Colombia) and Tungurahua (Ecuador).
Helmke Hepach, Birgit Quack, Susann Tegtmeier, Anja Engel, Astrid Bracher, Steffen Fuhlbrügge, Luisa Galgani, Elliot L. Atlas, Johannes Lampel, Udo Frieß, and Kirstin Krüger
Atmos. Chem. Phys., 16, 12219–12237, https://doi.org/10.5194/acp-16-12219-2016, https://doi.org/10.5194/acp-16-12219-2016, 2016
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We present surface seawater measurements of bromo- and iodocarbons, which are involved in numerous atmospheric processes such as tropospheric and stratospheric ozone chemistry, from the highly productive Peruvian upwelling. By combining trace gas measurements, characterization of organic matter and phytoplankton species, and tropospheric modelling, we show that large amounts of iodocarbons produced from the pool of organic matter may contribute strongly to local tropospheric iodine loading.
J. Lampel, D. Pöhler, J. Tschritter, U. Frieß, and U. Platt
Atmos. Meas. Tech., 8, 4329–4346, https://doi.org/10.5194/amt-8-4329-2015, https://doi.org/10.5194/amt-8-4329-2015, 2015
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In recent updates of the HITRAN water vapour H2O spectroscopic compilation covering the blue spectral region (here 394–-480 nm) significant changes for the absorption bands at 416 and 426 nm were reported. In order to investigate the consistency of the different cross sections calculated from these compilations, H2O vapour column density ratios for different spectral intervals were retrieved from long-path and multi-axis differential optical absorption spectroscopy measurements.
J. Lampel, U. Frieß, and U. Platt
Atmos. Meas. Tech., 8, 3767–3787, https://doi.org/10.5194/amt-8-3767-2015, https://doi.org/10.5194/amt-8-3767-2015, 2015
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In remote sensing applications, such as differential optical absorption spectroscopy (DOAS), atmospheric scattering processes need to be considered. Inelastic scattering on air molecules can lead to filling-in of absorption lines. The contribution of rotational Raman scattering is typically corrected for. The magnitude of vibrational Raman scattering (VRS) is known from theory and agrees with our first DOAS observations of this effect. Its impact on trace-gas measurements of NO2 is discussed.
K. Großmann, U. Frieß, E. Peters, F. Wittrock, J. Lampel, S. Yilmaz, J. Tschritter, R. Sommariva, R. von Glasow, B. Quack, K. Krüger, K. Pfeilsticker, and U. Platt
Atmos. Chem. Phys., 13, 3363–3378, https://doi.org/10.5194/acp-13-3363-2013, https://doi.org/10.5194/acp-13-3363-2013, 2013
Ramina Alwarda, Kristof Bognar, Xiaoyi Zhao, Vitali Fioletov, Jonathan Davies, Sum Chi Lee, Debora Griffin, Alexandru Lupu, Udo Frieß, Alexander Cede, Yushan Su, and Kimberly Strong
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-180, https://doi.org/10.5194/amt-2024-180, 2024
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Nitrogen dioxide (NO2) is a pollutant with a short lifetime and large variability, but there are limited measurements of its distribution in the lower atmosphere. We present a new dataset of three years of NO2 vertical profiles in Toronto, Canada, and evaluate it using NO2 from satellite and surface monitoring networks and simulations by an air quality forecast model. We quantify and explain the differences among the datasets to provide information that can be used to understand NO2 variability.
Leon Kuhn, Steffen Beirle, Sergey Osipov, Andrea Pozzer, and Thomas Wagner
Atmos. Meas. Tech., 17, 6485–6516, https://doi.org/10.5194/amt-17-6485-2024, https://doi.org/10.5194/amt-17-6485-2024, 2024
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This paper presents a new machine learning model that allows us to compute NO2 concentration profiles from satellite observations. A neural network was trained on synthetic data from the regional chemistry and transport model WRF-Chem. This is the first model of its kind. We present a thorough model validation study, covering various seasons and regions of the world.
Yuhang Zhang, Huan Yu, Isabelle De Smedt, Jintai Lin, Nicolas Theys, Michel Van Roozendael, Gaia Pinardi, Steven Compernolle, Ruijing Ni, Fangxuan Ren, Sijie Wang, Lulu Chen, Jos Van Geffen, Mengyao Liu, Alexander Cede, Alexis Merlaud, Martina Friedrich, Andreas Richter, Ankie Piters, Vinod Kumar, Vinayak Sinha, Thomas Wagner, Yongjoo Choi, Hisahiro Takashima, Yugo Kanaya, Hitoshi Irie, Robert Spurr, Wenfu Sun, and Lorenzo Fabris
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-182, https://doi.org/10.5194/amt-2024-182, 2024
Preprint under review for AMT
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We developed an advanced POMINO algorithm for global retrieval of TROPOMI HCHO and NO2 VCDs with much improved consistency. Sensitivity tests demonstrate the complexity and non-linear interactions of auxiliary parameters in the AMF calculation. An improved agreement is found with measurements from a global ground-based instrument network. The POMINO retrieval provides a useful source of information for studies combining HCHO and NO2.
Kezia Lange, Andreas Richter, Tim Bösch, Bianca Zilker, Miriam Latsch, Lisa K. Behrens, Chisom M. Okafor, Hartmut Bösch, John P. Burrows, Alexis Merlaud, Gaia Pinardi, Caroline Fayt, Martina M. Friedrich, Ermioni Dimitropoulou, Michel Van Roozendael, Steffen Ziegler, Simona Ripperger-Lukosiunaite, Leon Kuhn, Bianca Lauster, Thomas Wagner, Hyunkee Hong, Donghee Kim, Lim-Seok Chang, Kangho Bae, Chang-Keun Song, Jong-Uk Park, and Hanlim Lee
Atmos. Meas. Tech., 17, 6315–6344, https://doi.org/10.5194/amt-17-6315-2024, https://doi.org/10.5194/amt-17-6315-2024, 2024
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Instruments for air quality observations on geostationary satellites provide multiple observations per day and allow for the analysis of the diurnal variation of important air pollutants such as nitrogen dioxide (NO2) over large areas. The South Korean instrument GEMS, launched in February 2020, is the first instrument in geostationary orbit and covers a large part of Asia. Our investigations show the observed diurnal evolution of NO2 at different measurement sites.
Tim Trent, Marc Schröder, Shu-Peng Ho, Steffen Beirle, Ralf Bennartz, Eva Borbas, Christian Borger, Helene Brogniez, Xavier Calbet, Elisa Castelli, Gilbert P. Compo, Wesley Ebisuzaki, Ulrike Falk, Frank Fell, John Forsythe, Hans Hersbach, Misako Kachi, Shinya Kobayashi, Robert E. Kursinski, Diego Loyola, Zhengzao Luo, Johannes K. Nielsen, Enzo Papandrea, Laurence Picon, Rene Preusker, Anthony Reale, Lei Shi, Laura Slivinski, Joao Teixeira, Tom Vonder Haar, and Thomas Wagner
Atmos. Chem. Phys., 24, 9667–9695, https://doi.org/10.5194/acp-24-9667-2024, https://doi.org/10.5194/acp-24-9667-2024, 2024
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In a warmer future, water vapour will spend more time in the atmosphere, changing global rainfall patterns. In this study, we analysed the performance of 28 water vapour records between 1988 and 2014. We find sensitivity to surface warming generally outside expected ranges, attributed to breakpoints in individual record trends and differing representations of climate variability. The implication is that longer records are required for high confidence in assessing climate trends.
Chengxin Zhang, Xinhan Niu, Hongyu Wu, Zhipeng Ding, Ka Lok Chan, Jhoon Kim, Thomas Wagner, and Cheng Liu
EGUsphere, https://doi.org/10.5194/egusphere-2024-2620, https://doi.org/10.5194/egusphere-2024-2620, 2024
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This research utilizes hourly air pollution observations from the world’s first geostationary satellite to develop a spatiotemporal neural network model for full-coverage surface NO2 pollution prediction over the next 24 hours, achieving outstanding forecasting performance and efficacy. These results highlight the profound impact of geostationary satellite observations in advancing air quality forecasting models, thereby contributing to future models for health exposure to air pollution.
Steffen Beirle and Thomas Wagner
Atmos. Meas. Tech., 17, 3439–3453, https://doi.org/10.5194/amt-17-3439-2024, https://doi.org/10.5194/amt-17-3439-2024, 2024
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We present a new method for estimating emissions and lifetimes for nitrogen oxides emitted from large cities by using satellite NO2 observations combined with wind fields. The estimate is based on the simultaneous evaluation of the downwind plumes for opposing wind directions. This allows us to derive seasonal mean emissions and lifetimes for 100 cities around the globe.
Markus Knoll, Martin Penz, Hannes Juchem, Christina Schmidt, Denis Pöhler, and Alexander Bergmann
Atmos. Meas. Tech., 17, 2481–2505, https://doi.org/10.5194/amt-17-2481-2024, https://doi.org/10.5194/amt-17-2481-2024, 2024
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Exhaust emissions from combustion-based vehicles are negatively affecting human health and our environment. In particular, a small share (< 20 %) of poorly maintained or tampered vehicles are responsible for the majority (60 %–90 %) of traffic-related emissions. The emissions from vehicles are currently not properly monitored during their lifetime. We present a roadside measurement technique, called
point sampling, which can be used to monitor vehicle emissions throughout their life cycle.
Fei Liu, Steffen Beirle, Joanna Joiner, Sungyeon Choi, Zhining Tao, K. Emma Knowland, Steven J. Smith, Daniel Q. Tong, Siqi Ma, Zachary T. Fasnacht, and Thomas Wagner
Atmos. Chem. Phys., 24, 3717–3728, https://doi.org/10.5194/acp-24-3717-2024, https://doi.org/10.5194/acp-24-3717-2024, 2024
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Using satellite data, we developed a coupled method independent of the chemical transport model to map NOx emissions across US cities. After validating our technique with synthetic data, we charted NOx emissions from 2018–2021 in 39 cities. Our results closely matched EPA estimates but also highlighted some inconsistencies in both magnitude and spatial distribution. This research can help refine strategies for monitoring and managing air quality.
Thomas Wagner and Jānis Puķīte
Atmos. Meas. Tech., 17, 277–297, https://doi.org/10.5194/amt-17-277-2024, https://doi.org/10.5194/amt-17-277-2024, 2024
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We present a radiance calibration method based on the comparison of measurements and radiative transfer simulations of the zenith-scattered sun radiance during twilight. Cloud-free conditions are required. The method can be applied to measurements in the filed, and no laboratory measurements are required. The accuracy is estimated to range from about 4 % at 340 nm to about 10 % at 700 nm.
Glenn-Michael Oomen, Jean-François Müller, Trissevgeni Stavrakou, Isabelle De Smedt, Thomas Blumenstock, Rigel Kivi, Maria Makarova, Mathias Palm, Amelie Röhling, Yao Té, Corinne Vigouroux, Martina M. Friedrich, Udo Frieß, François Hendrick, Alexis Merlaud, Ankie Piters, Andreas Richter, Michel Van Roozendael, and Thomas Wagner
Atmos. Chem. Phys., 24, 449–474, https://doi.org/10.5194/acp-24-449-2024, https://doi.org/10.5194/acp-24-449-2024, 2024
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Natural emissions from vegetation have a profound impact on air quality for their role in the formation of harmful tropospheric ozone and organic aerosols, yet these emissions are highly uncertain. In this study, we quantify emissions of organic gases over Europe using high-quality satellite measurements of formaldehyde. These satellite observations suggest that emissions from vegetation are much higher than predicted by models, especially in southern Europe.
Leon Kuhn, Steffen Beirle, Vinod Kumar, Sergey Osipov, Andrea Pozzer, Tim Bösch, Rajesh Kumar, and Thomas Wagner
Atmos. Chem. Phys., 24, 185–217, https://doi.org/10.5194/acp-24-185-2024, https://doi.org/10.5194/acp-24-185-2024, 2024
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NO₂ is an important air pollutant. It was observed that the WRF-Chem model shows significant deviations in NO₂ abundance when compared to measurements. We use a 1-month simulation over central Europe to show that these deviations can be mostly resolved by reparameterization of the vertical mixing routine. In order to validate our results, they are compared to in situ, satellite, and MAX-DOAS measurements.
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.
Yuhang Zhang, Jintai Lin, Jhoon Kim, Hanlim Lee, Junsung Park, Hyunkee Hong, Michel Van Roozendael, Francois Hendrick, Ting Wang, Pucai Wang, Qin He, Kai Qin, Yongjoo Choi, Yugo Kanaya, Jin Xu, Pinhua Xie, Xin Tian, Sanbao Zhang, Shanshan Wang, Siyang Cheng, Xinghong Cheng, Jianzhong Ma, Thomas Wagner, Robert Spurr, Lulu Chen, Hao Kong, and Mengyao Liu
Atmos. Meas. Tech., 16, 4643–4665, https://doi.org/10.5194/amt-16-4643-2023, https://doi.org/10.5194/amt-16-4643-2023, 2023
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Our tropospheric NO2 vertical column density product with high spatiotemporal resolution is based on the Geostationary Environment Monitoring Spectrometer (GEMS) and named POMINO–GEMS. Strong hotspot signals and NO2 diurnal variations are clearly seen. Validations with multiple satellite products and ground-based, mobile car and surface measurements exhibit the overall great performance of the POMINO–GEMS product, indicating its capability for application in environmental studies.
Herizo Narivelo, Paul David Hamer, Virginie Marécal, Luke Surl, Tjarda Roberts, Sophie Pelletier, Béatrice Josse, Jonathan Guth, Mickaël Bacles, Simon Warnach, Thomas Wagner, Stefano Corradini, Giuseppe Salerno, and Lorenzo Guerrieri
Atmos. Chem. Phys., 23, 10533–10561, https://doi.org/10.5194/acp-23-10533-2023, https://doi.org/10.5194/acp-23-10533-2023, 2023
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Volcanic emissions emit large quantities of gases and primary aerosols that can play an important role in atmospheric chemistry. We present a study of the fate of volcanic bromine emissions from the eruption of Mount Etna around Christmas 2018. Using a numerical model and satellite observations, we analyse the impact of the volcanic plume and how it modifies the composition of the air over the whole Mediterranean basin, in particular on tropospheric ozone through the bromine-explosion cycle.
Steffen Beirle, Christian Borger, Adrian Jost, and Thomas Wagner
Earth Syst. Sci. Data, 15, 3051–3073, https://doi.org/10.5194/essd-15-3051-2023, https://doi.org/10.5194/essd-15-3051-2023, 2023
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We present a catalog of nitrogen oxide emissions from point sources (like power plants or metal smelters) based on satellite observations of NO2 combined with meteorological wind fields.
Christian Borger, Steffen Beirle, and Thomas Wagner
Earth Syst. Sci. Data, 15, 3023–3049, https://doi.org/10.5194/essd-15-3023-2023, https://doi.org/10.5194/essd-15-3023-2023, 2023
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This study presents a long-term data set of monthly mean total column water vapour (TCWV) based on measurements of the Ozone Monitoring Instrument (OMI) covering the time range from January 2005 to December 2020. We describe how the TCWV values are retrieved from UV–Vis satellite spectra and demonstrate that the OMI TCWV data set is in good agreement with various different reference data sets. Moreover, we also show that it fulfills typical stability requirements for climate data records.
Robert G. Ryan, Eloise A. Marais, Eleanor Gershenson-Smith, Robbie Ramsay, Jan-Peter Muller, Jan-Lukas Tirpitz, and Udo Frieß
Atmos. Chem. Phys., 23, 7121–7139, https://doi.org/10.5194/acp-23-7121-2023, https://doi.org/10.5194/acp-23-7121-2023, 2023
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We describe the first data retrieval from a newly installed instrument providing measurements of vertical profiles of air pollution over Central London during heatwaves in summer 2022. We use these observations with surface air quality network measurements to support interpretation that an exponential increase in biogenic emissions of isoprene during heatwaves provides the limiting ingredient for severe ozone pollution, leading to non-compliance with the national ozone air quality standard.
Ka Lok Chan, Pieter Valks, Klaus-Peter Heue, Ronny Lutz, Pascal Hedelt, Diego Loyola, Gaia Pinardi, Michel Van Roozendael, François Hendrick, Thomas Wagner, Vinod Kumar, Alkis Bais, Ankie Piters, Hitoshi Irie, Hisahiro Takashima, Yugo Kanaya, Yongjoo Choi, Kihong Park, Jihyo Chong, Alexander Cede, Udo Frieß, Andreas Richter, Jianzhong Ma, Nuria Benavent, Robert Holla, Oleg Postylyakov, Claudia Rivera Cárdenas, and Mark Wenig
Earth Syst. Sci. Data, 15, 1831–1870, https://doi.org/10.5194/essd-15-1831-2023, https://doi.org/10.5194/essd-15-1831-2023, 2023
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This paper presents the theoretical basis as well as verification and validation of the Global Ozone Monitoring Experiment-2 (GOME-2) daily and monthly level-3 products.
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.
Siyang Cheng, Xinghong Cheng, Jianzhong Ma, Xiangde Xu, Wenqian Zhang, Jinguang Lv, Gang Bai, Bing Chen, Siying Ma, Steffen Ziegler, Sebastian Donner, and Thomas Wagner
Atmos. Chem. Phys., 23, 3655–3677, https://doi.org/10.5194/acp-23-3655-2023, https://doi.org/10.5194/acp-23-3655-2023, 2023
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We made mobile MAX-DOAS measurements in the background atmosphere over the Tibetan Plateau in summer 2021. We retrieved the tropospheric NO2 and HCHO vertical column densities (VCDs) along extended driving routes and found a decreasing trend of the VCDs with altitude. Elevated NO2 VCDs along the driving routes could be attributed to enhanced traffic emissions from the towns crossed. The spatio-temporal distribution of the HCHO VCDs correlated strongly with the surface temperature.
Kezia Lange, Andreas Richter, Anja Schönhardt, Andreas C. Meier, Tim Bösch, André Seyler, Kai Krause, Lisa K. Behrens, Folkard Wittrock, Alexis Merlaud, Frederik Tack, Caroline Fayt, Martina M. Friedrich, Ermioni Dimitropoulou, Michel Van Roozendael, Vinod Kumar, Sebastian Donner, Steffen Dörner, Bianca Lauster, Maria Razi, Christian Borger, Katharina Uhlmannsiek, Thomas Wagner, Thomas Ruhtz, Henk Eskes, Birger Bohn, Daniel Santana Diaz, Nader Abuhassan, Dirk Schüttemeyer, and John P. Burrows
Atmos. Meas. Tech., 16, 1357–1389, https://doi.org/10.5194/amt-16-1357-2023, https://doi.org/10.5194/amt-16-1357-2023, 2023
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We present airborne imaging DOAS and ground-based stationary and car DOAS measurements conducted during the S5P-VAL-DE-Ruhr campaign in the Rhine-Ruhr region. The measurements are used to validate spaceborne NO2 data products from the Sentinel-5 Precursor TROPOspheric Monitoring Instrument (TROPOMI). Auxiliary data of the TROPOMI NO2 retrieval, such as spatially higher resolved a priori NO2 vertical profiles, surface reflectivity, and cloud treatment are investigated to evaluate their impact.
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.
Bianca Lauster, Steffen Dörner, Carl-Fredrik Enell, Udo Frieß, Myojeong Gu, Janis Puķīte, Uwe Raffalski, and Thomas Wagner
Atmos. Chem. Phys., 22, 15925–15942, https://doi.org/10.5194/acp-22-15925-2022, https://doi.org/10.5194/acp-22-15925-2022, 2022
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Polar stratospheric clouds (PSCs) are an important component in ozone chemistry. Here, we use two differential optical absorption spectroscopy (DOAS) instruments in the Antarctic and Arctic to investigate the occurrence of PSCs based on the colour index, i.e. the colour of the zenith sky. Additionally using radiative transfer simulations, the variability and the seasonal cycle of PSC occurrence are analysed and an unexpectedly high signal during spring suggests the influence of volcanic aerosol.
Miriam Latsch, Andreas Richter, Henk Eskes, Maarten Sneep, Ping Wang, Pepijn Veefkind, Ronny Lutz, Diego Loyola, Athina Argyrouli, Pieter Valks, Thomas Wagner, Holger Sihler, Michel van Roozendael, Nicolas Theys, Huan Yu, Richard Siddans, and John P. Burrows
Atmos. Meas. Tech., 15, 6257–6283, https://doi.org/10.5194/amt-15-6257-2022, https://doi.org/10.5194/amt-15-6257-2022, 2022
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The article investigates different S5P TROPOMI cloud retrieval algorithms for tropospheric trace gas retrievals. The cloud products show differences primarily over snow and ice and for scenes under sun glint. Some issues regarding across-track dependence are found for the cloud fractions as well as for the cloud heights.
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.
Christian Borger, Steffen Beirle, and Thomas Wagner
Atmos. Chem. Phys., 22, 10603–10621, https://doi.org/10.5194/acp-22-10603-2022, https://doi.org/10.5194/acp-22-10603-2022, 2022
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In this study, we analyse trends of total column water vapour (TCWV) using multiple years of satellite observations and find, on the global average, an increase in the TCWV amount by about 0.21 % per year. Further investigations of the hydrological cycle reveal that the assumption of temporally invariant relative humidity is not always fulfilled and that the response of the global water vapour turnover time to global warming is 2 to 3 times higher than previously reported values.
Gaia Pinardi, Michel Van Roozendael, François Hendrick, Andreas Richter, Pieter Valks, Ramina Alwarda, Kristof Bognar, Udo Frieß, José Granville, Myojeong Gu, Paul Johnston, Cristina Prados-Roman, Richard Querel, Kimberly Strong, Thomas Wagner, Folkard Wittrock, and Margarita Yela Gonzalez
Atmos. Meas. Tech., 15, 3439–3463, https://doi.org/10.5194/amt-15-3439-2022, https://doi.org/10.5194/amt-15-3439-2022, 2022
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We report on the GOME-2A and GOME-2B OClO dataset (2007 to 2016, from the EUMETSAT's AC SAF) validation using data from nine NDACC zenith-scattered-light DOAS (ZSL-DOAS) instruments distributed in both the Arctic and Antarctic. Specific sensitivity tests are performed on the ground-based data to estimate the impact of the different OClO DOAS analysis settings and their typical errors. Good agreement is found for both the inter-annual variability and the overall OClO seasonal behavior.
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.
Gerrit Kuhlmann, Ka Lok Chan, Sebastian Donner, Ying Zhu, Marc Schwaerzel, Steffen Dörner, Jia Chen, Andreas Hueni, Duc Hai Nguyen, Alexander Damm, Annette Schütt, Florian Dietrich, Dominik Brunner, Cheng Liu, Brigitte Buchmann, Thomas Wagner, and Mark Wenig
Atmos. Meas. Tech., 15, 1609–1629, https://doi.org/10.5194/amt-15-1609-2022, https://doi.org/10.5194/amt-15-1609-2022, 2022
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Nitrogen dioxide (NO2) is an air pollutant whose concentration often exceeds air quality guideline values, especially in urban areas. To map the spatial distribution of NO2 in Munich, we conducted the Munich NO2 Imaging Campaign (MuNIC), where NO2 was measured with stationary, mobile, and airborne in situ and remote sensing instruments. The campaign provides a unique dataset that has been used to compare the different instruments and to study the spatial variability of NO2 and its sources.
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.
Dimitris Karagkiozidis, Martina Michaela Friedrich, Steffen Beirle, Alkiviadis Bais, François Hendrick, Kalliopi Artemis Voudouri, Ilias Fountoulakis, Angelos Karanikolas, Paraskevi Tzoumaka, Michel Van Roozendael, Dimitris Balis, and Thomas Wagner
Atmos. Meas. Tech., 15, 1269–1301, https://doi.org/10.5194/amt-15-1269-2022, https://doi.org/10.5194/amt-15-1269-2022, 2022
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In this study we focus on the retrieval of aerosol, NO2, and HCHO vertical profiles from multi-axis differential optical absorption spectroscopy (MAX-DOAS) observations for the first time over Thessaloniki, Greece. We use two independent inversion algorithms for the profile retrievals. We evaluate their performance, we intercompare their results, and we validate their products with ancillary data, measured by other co-located reference instruments.
Steffen Beirle, Christian Borger, Steffen Dörner, Vinod Kumar, and Thomas Wagner
Atmos. Meas. Tech., 15, 987–1006, https://doi.org/10.5194/amt-15-987-2022, https://doi.org/10.5194/amt-15-987-2022, 2022
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We present a formalism that relates the vertical column density (VCD) of the oxygen collision complex O4 to surface values of temperature and pressure, based on physical laws. In addition, we propose an empirical modification which also accounts for surface relative humidity (RH). This allows for simple and quick but still accurate calculation of the O4 VCD without the need for constructing full vertical profiles, which is expected to be useful in particular for MAX-DOAS applications.
Fei Liu, Zhining Tao, Steffen Beirle, Joanna Joiner, Yasuko Yoshida, Steven J. Smith, K. Emma Knowland, and Thomas Wagner
Atmos. Chem. Phys., 22, 1333–1349, https://doi.org/10.5194/acp-22-1333-2022, https://doi.org/10.5194/acp-22-1333-2022, 2022
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In this work, we present a novel method to infer NOx emissions and lifetimes based on tropospheric NO2 observations together with reanalysis wind fields for cities located in polluted backgrounds. We evaluate the accuracy of the method using synthetic NO2 observations derived from a high-resolution model simulation. Our work provides an estimate for uncertainties in satellite-derived emissions inferred from chemical transport model (CTM)-independent approaches.
Tobias Küchler, Stefan Noël, Heinrich Bovensmann, John Philip Burrows, Thomas Wagner, Christian Borger, Tobias Borsdorff, and Andreas Schneider
Atmos. Meas. Tech., 15, 297–320, https://doi.org/10.5194/amt-15-297-2022, https://doi.org/10.5194/amt-15-297-2022, 2022
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We applied the air-mass-corrected differential optical absorption spectroscopy (AMC-DOAS) method to derive total column water vapour (TCWV) from Sentinel-5P measurements and compared it to independent data sets. The correlation coefficients of typically more than 0.9 and the small deviations up to 2.5 kg m−2 reveal good agreement between our data product and other TCWV data sets. In particular for the different Sentinel-5P water vapour products, the deviations are around 1 kg m−2.
Jānis Puķīte, Christian Borger, Steffen Dörner, Myojeong Gu, and Thomas Wagner
Atmos. Chem. Phys., 22, 245–272, https://doi.org/10.5194/acp-22-245-2022, https://doi.org/10.5194/acp-22-245-2022, 2022
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Chlorine dioxide (OClO) is an indicator for chlorine activation. New OClO data by TROPOMI (S5P) are interpreted in a meteorological context and related to CALIOP PSC observations. We report very high OClO levels for the northern hemispheric winter 2019/20 with an extraordinarily long period with a stable polar vortex. A minor stratospheric warming in the Southern Hemisphere was also observed in September 2019, where usual OClO values rapidly deactivated 1–2 weeks earlier.
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.
Christophe Lerot, François Hendrick, Michel Van Roozendael, Leonardo M. A. Alvarado, Andreas Richter, Isabelle De Smedt, Nicolas Theys, Jonas Vlietinck, Huan Yu, Jeroen Van Gent, Trissevgeni Stavrakou, Jean-François Müller, Pieter Valks, Diego Loyola, Hitoshi Irie, Vinod Kumar, Thomas Wagner, Stefan F. Schreier, Vinayak Sinha, Ting Wang, Pucai Wang, and Christian Retscher
Atmos. Meas. Tech., 14, 7775–7807, https://doi.org/10.5194/amt-14-7775-2021, https://doi.org/10.5194/amt-14-7775-2021, 2021
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Global measurements of glyoxal tropospheric columns from the satellite instrument TROPOMI are presented. Such measurements can contribute to the estimation of atmospheric emissions of volatile organic compounds. This new glyoxal product has been fully characterized with a comprehensive error budget, with comparison with other satellite data sets as well as with validation based on independent ground-based remote sensing glyoxal observations.
Jānis Puķīte, Christian Borger, Steffen Dörner, Myojeong Gu, Udo Frieß, Andreas Carlos Meier, Carl-Fredrik Enell, Uwe Raffalski, Andreas Richter, and Thomas Wagner
Atmos. Meas. Tech., 14, 7595–7625, https://doi.org/10.5194/amt-14-7595-2021, https://doi.org/10.5194/amt-14-7595-2021, 2021
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Chlorine dioxide (OClO) is used as an indicator for chlorine activation. We present a new differential optical absorption spectroscopy retrieval algorithm for OClO from measurements of TROPOMI on the Sentinel-5P satellite. To achieve a substantially improved accuracy for the weak absorber OClO, we consider several additional fit parameters accounting for various higher-order spectral effects. The retrieved OClO slant column densities are compared with ground-based zenith sky measurements.
Song Liu, Pieter Valks, Gaia Pinardi, Jian Xu, Ka Lok Chan, Athina Argyrouli, Ronny Lutz, Steffen Beirle, Ehsan Khorsandi, Frank Baier, Vincent Huijnen, Alkiviadis Bais, Sebastian Donner, Steffen Dörner, Myrto Gratsea, François Hendrick, Dimitris Karagkiozidis, Kezia Lange, Ankie J. M. Piters, Julia Remmers, Andreas Richter, Michel Van Roozendael, Thomas Wagner, Mark Wenig, and Diego G. Loyola
Atmos. Meas. Tech., 14, 7297–7327, https://doi.org/10.5194/amt-14-7297-2021, https://doi.org/10.5194/amt-14-7297-2021, 2021
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In this work, an improved tropospheric NO2 retrieval algorithm from TROPOMI measurements over Europe is presented. The stratospheric estimation is implemented with correction for the dependency of the stratospheric NO2 on the viewing geometry. The AMF calculation is implemented using improved surface albedo, a priori NO2 profiles, and cloud correction. The improved tropospheric NO2 data show good correlations with ground-based MAX-DOAS measurements.
Nicolas Theys, Vitali Fioletov, Can Li, Isabelle De Smedt, Christophe Lerot, Chris McLinden, Nickolay Krotkov, Debora Griffin, Lieven Clarisse, Pascal Hedelt, Diego Loyola, Thomas Wagner, Vinod Kumar, Antje Innes, Roberto Ribas, François Hendrick, Jonas Vlietinck, Hugues Brenot, and Michel Van Roozendael
Atmos. Chem. Phys., 21, 16727–16744, https://doi.org/10.5194/acp-21-16727-2021, https://doi.org/10.5194/acp-21-16727-2021, 2021
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We present a new algorithm to retrieve sulfur dioxide from space UV measurements. We apply the technique to high-resolution TROPOMI measurements and demonstrate the high sensitivity of the approach to weak SO2 emissions worldwide with an unprecedented limit of detection of 8 kt yr−1. This result has broad implications for atmospheric science studies dealing with improving emission inventories and identifying and quantifying missing sources, in the context of air quality and climate.
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.
Xin Tian, Yang Wang, Steffen Beirle, Pinhua Xie, Thomas Wagner, Jin Xu, Ang Li, Steffen Dörner, Bo Ren, and Xiaomei Li
Atmos. Chem. Phys., 21, 12867–12894, https://doi.org/10.5194/acp-21-12867-2021, https://doi.org/10.5194/acp-21-12867-2021, 2021
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The performances of two MAX-DOAS inversion algorithms were evaluated for various aerosol pollution scenarios. One inversion algorithm is based on optimal estimation; the other uses a parameterized approach. In this analysis, three types of profile shapes for aerosols and NO2 were considered: exponential, Boltzmann, and Gaussian. The evaluation results can effectively guide the application of the two inversion algorithms in the actual atmosphere and improve the accuracy of the actual inversion.
Bjorn Stevens, Sandrine Bony, David Farrell, Felix Ament, Alan Blyth, Christopher Fairall, Johannes Karstensen, Patricia K. Quinn, Sabrina Speich, Claudia Acquistapace, Franziska Aemisegger, Anna Lea Albright, Hugo Bellenger, Eberhard Bodenschatz, Kathy-Ann Caesar, Rebecca Chewitt-Lucas, Gijs de Boer, Julien Delanoë, Leif Denby, Florian Ewald, Benjamin Fildier, Marvin Forde, Geet George, Silke Gross, Martin Hagen, Andrea Hausold, Karen J. Heywood, Lutz Hirsch, Marek Jacob, Friedhelm Jansen, Stefan Kinne, Daniel Klocke, Tobias Kölling, Heike Konow, Marie Lothon, Wiebke Mohr, Ann Kristin Naumann, Louise Nuijens, Léa Olivier, Robert Pincus, Mira Pöhlker, Gilles Reverdin, Gregory Roberts, Sabrina Schnitt, Hauke Schulz, A. Pier Siebesma, Claudia Christine Stephan, Peter Sullivan, Ludovic Touzé-Peiffer, Jessica Vial, Raphaela Vogel, Paquita Zuidema, Nicola Alexander, Lyndon Alves, Sophian Arixi, Hamish Asmath, Gholamhossein Bagheri, Katharina Baier, Adriana Bailey, Dariusz Baranowski, Alexandre Baron, Sébastien Barrau, Paul A. Barrett, Frédéric Batier, Andreas Behrendt, Arne Bendinger, Florent Beucher, Sebastien Bigorre, Edmund Blades, Peter Blossey, Olivier Bock, Steven Böing, Pierre Bosser, Denis Bourras, Pascale Bouruet-Aubertot, Keith Bower, Pierre Branellec, Hubert Branger, Michal Brennek, Alan Brewer, Pierre-Etienne Brilouet, Björn Brügmann, Stefan A. Buehler, Elmo Burke, Ralph Burton, Radiance Calmer, Jean-Christophe Canonici, Xavier Carton, Gregory Cato Jr., Jude Andre Charles, Patrick Chazette, Yanxu Chen, Michal T. Chilinski, Thomas Choularton, Patrick Chuang, Shamal Clarke, Hugh Coe, Céline Cornet, Pierre Coutris, Fleur Couvreux, Susanne Crewell, Timothy Cronin, Zhiqiang Cui, Yannis Cuypers, Alton Daley, Gillian M. Damerell, Thibaut Dauhut, Hartwig Deneke, Jean-Philippe Desbios, Steffen Dörner, Sebastian Donner, Vincent Douet, Kyla Drushka, Marina Dütsch, André Ehrlich, Kerry Emanuel, Alexandros Emmanouilidis, Jean-Claude Etienne, Sheryl Etienne-Leblanc, Ghislain Faure, Graham Feingold, Luca Ferrero, Andreas Fix, Cyrille Flamant, Piotr Jacek Flatau, Gregory R. Foltz, Linda Forster, Iulian Furtuna, Alan Gadian, Joseph Galewsky, Martin Gallagher, Peter Gallimore, Cassandra Gaston, Chelle Gentemann, Nicolas Geyskens, Andreas Giez, John Gollop, Isabelle Gouirand, Christophe Gourbeyre, Dörte de Graaf, Geiske E. de Groot, Robert Grosz, Johannes Güttler, Manuel Gutleben, Kashawn Hall, George Harris, Kevin C. Helfer, Dean Henze, Calvert Herbert, Bruna Holanda, Antonio Ibanez-Landeta, Janet Intrieri, Suneil Iyer, Fabrice Julien, Heike Kalesse, Jan Kazil, Alexander Kellman, Abiel T. Kidane, Ulrike Kirchner, Marcus Klingebiel, Mareike Körner, Leslie Ann Kremper, Jan Kretzschmar, Ovid Krüger, Wojciech Kumala, Armin Kurz, Pierre L'Hégaret, Matthieu Labaste, Tom Lachlan-Cope, Arlene Laing, Peter Landschützer, Theresa Lang, Diego Lange, Ingo Lange, Clément Laplace, Gauke Lavik, Rémi Laxenaire, Caroline Le Bihan, Mason Leandro, Nathalie Lefevre, Marius Lena, Donald Lenschow, Qiang Li, Gary Lloyd, Sebastian Los, Niccolò Losi, Oscar Lovell, Christopher Luneau, Przemyslaw Makuch, Szymon Malinowski, Gaston Manta, Eleni Marinou, Nicholas Marsden, Sebastien Masson, Nicolas Maury, Bernhard Mayer, Margarette Mayers-Als, Christophe Mazel, Wayne McGeary, James C. McWilliams, Mario Mech, Melina Mehlmann, Agostino Niyonkuru Meroni, Theresa Mieslinger, Andreas Minikin, Peter Minnett, Gregor Möller, Yanmichel Morfa Avalos, Caroline Muller, Ionela Musat, Anna Napoli, Almuth Neuberger, Christophe Noisel, David Noone, Freja Nordsiek, Jakub L. Nowak, Lothar Oswald, Douglas J. Parker, Carolyn Peck, Renaud Person, Miriam Philippi, Albert Plueddemann, Christopher Pöhlker, Veronika Pörtge, Ulrich Pöschl, Lawrence Pologne, Michał Posyniak, Marc Prange, Estefanía Quiñones Meléndez, Jule Radtke, Karim Ramage, Jens Reimann, Lionel Renault, Klaus Reus, Ashford Reyes, Joachim Ribbe, Maximilian Ringel, Markus Ritschel, Cesar B. Rocha, Nicolas Rochetin, Johannes Röttenbacher, Callum Rollo, Haley Royer, Pauline Sadoulet, Leo Saffin, Sanola Sandiford, Irina Sandu, Michael Schäfer, Vera Schemann, Imke Schirmacher, Oliver Schlenczek, Jerome Schmidt, Marcel Schröder, Alfons Schwarzenboeck, Andrea Sealy, Christoph J. Senff, Ilya Serikov, Samkeyat Shohan, Elizabeth Siddle, Alexander Smirnov, Florian Späth, Branden Spooner, M. Katharina Stolla, Wojciech Szkółka, Simon P. de Szoeke, Stéphane Tarot, Eleni Tetoni, Elizabeth Thompson, Jim Thomson, Lorenzo Tomassini, Julien Totems, Alma Anna Ubele, Leonie Villiger, Jan von Arx, Thomas Wagner, Andi Walther, Ben Webber, Manfred Wendisch, Shanice Whitehall, Anton Wiltshire, Allison A. Wing, Martin Wirth, Jonathan Wiskandt, Kevin Wolf, Ludwig Worbes, Ethan Wright, Volker Wulfmeyer, Shanea Young, Chidong Zhang, Dongxiao Zhang, Florian Ziemen, Tobias Zinner, and Martin Zöger
Earth Syst. Sci. Data, 13, 4067–4119, https://doi.org/10.5194/essd-13-4067-2021, https://doi.org/10.5194/essd-13-4067-2021, 2021
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The EUREC4A field campaign, designed to test hypothesized mechanisms by which clouds respond to warming and benchmark next-generation Earth-system models, is presented. EUREC4A comprised roughly 5 weeks of measurements in the downstream winter trades of the North Atlantic – eastward and southeastward of Barbados. It was the first campaign that attempted to characterize the full range of processes and scales influencing trade wind clouds.
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.
Isabelle De Smedt, Gaia Pinardi, Corinne Vigouroux, Steven Compernolle, Alkis Bais, Nuria Benavent, Folkert Boersma, Ka-Lok Chan, Sebastian Donner, Kai-Uwe Eichmann, Pascal Hedelt, François Hendrick, Hitoshi Irie, Vinod Kumar, Jean-Christopher Lambert, Bavo Langerock, Christophe Lerot, Cheng Liu, Diego Loyola, Ankie Piters, Andreas Richter, Claudia Rivera Cárdenas, Fabian Romahn, Robert George Ryan, Vinayak Sinha, Nicolas Theys, Jonas Vlietinck, Thomas Wagner, Ting Wang, Huan Yu, and Michel Van Roozendael
Atmos. Chem. Phys., 21, 12561–12593, https://doi.org/10.5194/acp-21-12561-2021, https://doi.org/10.5194/acp-21-12561-2021, 2021
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This paper assess the performances of the TROPOMI formaldehyde observations compared to its predecessor OMI at different spatial and temporal scales. We also use a global network of MAX-DOAS instruments to validate both satellite datasets for a large range of HCHO columns. The precision obtained with daily TROPOMI observations is comparable to monthly OMI observations. We present clear detection of weak HCHO column enhancements related to shipping emissions in the Indian Ocean.
Anoop S. Mahajan, Mriganka S. Biswas, Steffen Beirle, Thomas Wagner, Anja Schönhardt, Nuria Benavent, and Alfonso Saiz-Lopez
Atmos. Chem. Phys., 21, 11829–11842, https://doi.org/10.5194/acp-21-11829-2021, https://doi.org/10.5194/acp-21-11829-2021, 2021
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Iodine plays a vital role in oxidation chemistry over Antarctica, with past observations showing highly elevated levels of iodine oxide (IO) leading to severe depletion of boundary layer ozone. We present IO observations over three summers (2015–2017) at the Indian Antarctic bases of Bharati and Maitri. IO was observed during all campaigns with mixing ratios below 2 pptv, which is lower than the peak levels observed in West Antarctica, showing the differences in regional chemistry and emissions.
Vinod Kumar, Julia Remmers, Steffen Beirle, Joachim Fallmann, Astrid Kerkweg, Jos Lelieveld, Mariano Mertens, Andrea Pozzer, Benedikt Steil, Marc Barra, Holger Tost, and Thomas Wagner
Atmos. Meas. Tech., 14, 5241–5269, https://doi.org/10.5194/amt-14-5241-2021, https://doi.org/10.5194/amt-14-5241-2021, 2021
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We present high-resolution regional atmospheric chemistry model simulations focused around Germany. We highlight the importance of spatial resolution of the model itself as well as the input emissions inventory and short-scale temporal variability of emissions for simulations. We propose a consistent approach for evaluating the simulated vertical distribution of NO2 using MAX-DOAS measurements while also considering its spatial sensitivity volume and change in sensitivity within this volume.
Steffen Beirle, Christian Borger, Steffen Dörner, Henk Eskes, Vinod Kumar, Adrianus de Laat, and Thomas Wagner
Earth Syst. Sci. Data, 13, 2995–3012, https://doi.org/10.5194/essd-13-2995-2021, https://doi.org/10.5194/essd-13-2995-2021, 2021
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A catalog of point sources of nitrogen oxides was created using satellite observations of NO2. Key for the identification of point sources was the divergence, i.e., the difference between upwind and downwind levels of NO2.
The catalog lists 451 locations, of which 242 could be automatically matched to power plants. Other point sources are metal smelters, cement plants, or industrial areas. The catalog thus allows checking and improving of existing emission inventories.
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.
Holger Sihler, Steffen Beirle, Steffen Dörner, Marloes Gutenstein-Penning de Vries, Christoph Hörmann, Christian Borger, Simon Warnach, and Thomas Wagner
Atmos. Meas. Tech., 14, 3989–4031, https://doi.org/10.5194/amt-14-3989-2021, https://doi.org/10.5194/amt-14-3989-2021, 2021
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MICRU is an algorithm for the retrieval of effective cloud fractions (CFs) from satellite measurements. CFs describe the amount of clouds, which have a significant impact on the vertical sensitivity profile of trace gases like NO2 and HCHO. MICRU retrieves small CFs with an accuracy of 0.04 over the entire satellite swath. It features an empirical surface reflectivity model accounting for physical anisotropy (BRDF, sun glitter) and instrumental effects. MICRU is also applicable to imager data.
Thomas Wagner, Steffen Dörner, Steffen Beirle, Sebastian Donner, and Stefan Kinne
Atmos. Meas. Tech., 14, 3871–3893, https://doi.org/10.5194/amt-14-3871-2021, https://doi.org/10.5194/amt-14-3871-2021, 2021
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We compare measured and simulated O4 absorptions for conditions of extremely low aerosol optical depth, for which the uncertainties related to imperfect knowledge of aerosol properties do not significantly affect the comparison results. The simulations underestimate the measurements by 15 % to 20 %. Even if no aerosols are considered, the simulated O4 absorptions are systematically lower than the measurements. Our results indicate a fundamental inconsistency between simulations and measurements.
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.
Thomas Wagner, Steffen Beirle, Steffen Dörner, Christian Borger, and Roeland Van Malderen
Atmos. Chem. Phys., 21, 5315–5353, https://doi.org/10.5194/acp-21-5315-2021, https://doi.org/10.5194/acp-21-5315-2021, 2021
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A global long-term (1995–2015) data set of total column water vapour (TCWV) derived from satellite observations is used to quantify the influence of teleconnections. Based on a newly developed empirical method more than 40 teleconnection indices are significantly detected in our global TCWV data set. After orthogonalisation, only 20 indices are left significant. The global distribution of the cumulative influence of teleconnection indices is strongest in the tropics and high latitudes.
Santiago Arellano, Bo Galle, Fredy Apaza, Geoffroy Avard, Charlotte Barrington, Nicole Bobrowski, Claudia Bucarey, Viviana Burbano, Mike Burton, Zoraida Chacón, Gustavo Chigna, Christian Joseph Clarito, Vladimir Conde, Fidel Costa, Maarten De Moor, Hugo Delgado-Granados, Andrea Di Muro, Deborah Fernandez, Gustavo Garzón, Hendra Gunawan, Nia Haerani, Thor H. Hansteen, Silvana Hidalgo, Salvatore Inguaggiato, Mattias Johansson, Christoph Kern, Manne Kihlman, Philippe Kowalski, Pablo Masias, Francisco Montalvo, Joakim Möller, Ulrich Platt, Claudia Rivera, Armando Saballos, Giuseppe Salerno, Benoit Taisne, Freddy Vásconez, Gabriela Velásquez, Fabio Vita, and Mathieu Yalire
Earth Syst. Sci. Data, 13, 1167–1188, https://doi.org/10.5194/essd-13-1167-2021, https://doi.org/10.5194/essd-13-1167-2021, 2021
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This study presents a dataset of volcanic sulfur dioxide (SO2) emissions from 2005–2017. Measurements were obtained by Network for Observation of Volcanic and Atmospheric Change (NOVAC) scanning differential optical absorption spectrometer (ScanDOAS) instruments at 32 volcanoes and processed using a standardized procedure. We show statistics of volcanic gas emissions under a variety of conditions and compare them with averages derived from measurements from space and historical inventories.
Bianca Lauster, Steffen Dörner, Steffen Beirle, Sebastian Donner, Sergey Gromov, Katharina Uhlmannsiek, and Thomas Wagner
Atmos. Meas. Tech., 14, 769–783, https://doi.org/10.5194/amt-14-769-2021, https://doi.org/10.5194/amt-14-769-2021, 2021
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In urban areas, road traffic is a dominant source of nitrogen oxides. In this study, two multi-axis differential optical absorption spectroscopy (MAX-DOAS) instruments on opposite sides of a motorway were used to measure the nitrogen dioxide absorption near Mainz, Germany. Total nitrogen oxide emissions are estimated for the occurring traffic flux. We show that the measured emissions systematically exceed the maximum expected emissions calculated from the European emission standards.
Tijl Verhoelst, Steven Compernolle, Gaia Pinardi, Jean-Christopher Lambert, Henk J. Eskes, Kai-Uwe Eichmann, Ann Mari Fjæraa, José Granville, Sander Niemeijer, Alexander Cede, Martin Tiefengraber, François Hendrick, Andrea Pazmiño, Alkiviadis Bais, Ariane Bazureau, K. Folkert Boersma, Kristof Bognar, Angelika Dehn, Sebastian Donner, Aleksandr Elokhov, Manuel Gebetsberger, Florence Goutail, Michel Grutter de la Mora, Aleksandr Gruzdev, Myrto Gratsea, Georg H. Hansen, Hitoshi Irie, Nis Jepsen, Yugo Kanaya, Dimitris Karagkiozidis, Rigel Kivi, Karin Kreher, Pieternel F. Levelt, Cheng Liu, Moritz Müller, Monica Navarro Comas, Ankie J. M. Piters, Jean-Pierre Pommereau, Thierry Portafaix, Cristina Prados-Roman, Olga Puentedura, Richard Querel, Julia Remmers, Andreas Richter, John Rimmer, Claudia Rivera Cárdenas, Lidia Saavedra de Miguel, Valery P. Sinyakov, Wolfgang Stremme, Kimberly Strong, Michel Van Roozendael, J. Pepijn Veefkind, Thomas Wagner, Folkard Wittrock, Margarita Yela González, and Claus Zehner
Atmos. Meas. Tech., 14, 481–510, https://doi.org/10.5194/amt-14-481-2021, https://doi.org/10.5194/amt-14-481-2021, 2021
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This paper reports on the ground-based validation of the NO2 data produced operationally by the TROPOMI instrument on board the Sentinel-5 Precursor satellite. Tropospheric, stratospheric, and total NO2 columns are compared to measurements collected from MAX-DOAS, ZSL-DOAS, and PGN/Pandora instruments respectively. The products are found to satisfy mission requirements in general, though negative mean differences are found at sites with high pollution levels. Potential causes are discussed.
Christopher Fuchs, Jonas Kuhn, Nicole Bobrowski, and Ulrich Platt
Atmos. Meas. Tech., 14, 295–307, https://doi.org/10.5194/amt-14-295-2021, https://doi.org/10.5194/amt-14-295-2021, 2021
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We present first measurements of volcanic SO2 emissions with a novel imaging technique for atmospheric trace gases in the UV and visible spectral range. Periodic spectral Fabry–Pérot interferometer transmission features are matched to differential absorption cross sections of the investigated trace gas, yielding high selectivity and sensitivity. The technique can be extended to measure many other trace gases with high spatio-temporal resolution.
Jan-Lukas Tirpitz, Udo Frieß, François Hendrick, Carlos Alberti, Marc Allaart, Arnoud Apituley, Alkis Bais, Steffen Beirle, Stijn Berkhout, Kristof Bognar, Tim Bösch, Ilya Bruchkouski, Alexander Cede, Ka Lok Chan, Mirjam den Hoed, Sebastian Donner, Theano Drosoglou, Caroline Fayt, Martina M. Friedrich, Arnoud Frumau, Lou Gast, Clio Gielen, Laura Gomez-Martín, Nan Hao, Arjan Hensen, Bas Henzing, Christian Hermans, Junli Jin, Karin Kreher, Jonas Kuhn, Johannes Lampel, Ang Li, Cheng Liu, Haoran Liu, Jianzhong Ma, Alexis Merlaud, Enno Peters, Gaia Pinardi, Ankie Piters, Ulrich Platt, Olga Puentedura, Andreas Richter, Stefan Schmitt, Elena Spinei, Deborah Stein Zweers, Kimberly Strong, Daan Swart, Frederik Tack, Martin Tiefengraber, René van der Hoff, Michel van Roozendael, Tim Vlemmix, Jan Vonk, Thomas Wagner, Yang Wang, Zhuoru Wang, Mark Wenig, Matthias Wiegner, Folkard Wittrock, Pinhua Xie, Chengzhi Xing, Jin Xu, Margarita Yela, Chengxin Zhang, and Xiaoyi Zhao
Atmos. Meas. Tech., 14, 1–35, https://doi.org/10.5194/amt-14-1-2021, https://doi.org/10.5194/amt-14-1-2021, 2021
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Multi-axis differential optical absorption spectroscopy (MAX-DOAS) is a ground-based remote sensing measurement technique that derives atmospheric aerosol and trace gas vertical profiles from skylight spectra. In this study, consistency and reliability of MAX-DOAS profiles are assessed by applying nine different evaluation algorithms to spectral data recorded during an intercomparison campaign in the Netherlands and by comparing the results to colocated supporting observations.
Vinod Kumar, Steffen Beirle, Steffen Dörner, Abhishek Kumar Mishra, Sebastian Donner, Yang Wang, Vinayak Sinha, and Thomas Wagner
Atmos. Chem. Phys., 20, 14183–14235, https://doi.org/10.5194/acp-20-14183-2020, https://doi.org/10.5194/acp-20-14183-2020, 2020
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We present the first long-term MAX-DOAS measurements of aerosols, nitrogen dioxide and formaldehyde tropospheric columns, vertical distributions, and temporal variation from Mohali in the Indo-Gangetic Plain. We investigate the effect of various emission sources and meteorological conditions on the measured pollutants and how they control ozone formation. These measurements are also used to validate the corresponding satellite observations and are also compared against in situ observations.
Gaia Pinardi, Michel Van Roozendael, François Hendrick, Nicolas Theys, Nader Abuhassan, Alkiviadis Bais, Folkert Boersma, Alexander Cede, Jihyo Chong, Sebastian Donner, Theano Drosoglou, Anatoly Dzhola, Henk Eskes, Udo Frieß, José Granville, Jay R. Herman, Robert Holla, Jari Hovila, Hitoshi Irie, Yugo Kanaya, Dimitris Karagkiozidis, Natalia Kouremeti, Jean-Christopher Lambert, Jianzhong Ma, Enno Peters, Ankie Piters, Oleg Postylyakov, Andreas Richter, Julia Remmers, Hisahiro Takashima, Martin Tiefengraber, Pieter Valks, Tim Vlemmix, Thomas Wagner, and Folkard Wittrock
Atmos. Meas. Tech., 13, 6141–6174, https://doi.org/10.5194/amt-13-6141-2020, https://doi.org/10.5194/amt-13-6141-2020, 2020
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We validate several GOME-2 and OMI tropospheric NO2 products with 23 MAX-DOAS and 16 direct sun instruments distributed worldwide, highlighting large horizontal inhomogeneities at several sites affecting the validation results. We propose a method for quantification and correction. We show the application of such correction reduces the satellite underestimation in almost all heterogeneous cases, but a negative bias remains over the MAX-DOAS and direct sun network ensemble for both satellites.
Yeyuan Huang, Ang Li, Thomas Wagner, Yang Wang, Zhaokun Hu, Pinhua Xie, Jin Xu, Hongmei Ren, Julia Remmers, Xiaoyi Fang, and Bing Dang
Atmos. Meas. Tech., 13, 6025–6051, https://doi.org/10.5194/amt-13-6025-2020, https://doi.org/10.5194/amt-13-6025-2020, 2020
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Mobile DOAS has become an important tool for the quantification of emission sources. In this study, we focused on the error budget of mobile DOAS measurements from NOx and SO2 point sources based on the model simulations, and we also offered recommendations for the optimum settings of such measurements.
Alexis Merlaud, Livio Belegante, Daniel-Eduard Constantin, Mirjam Den Hoed, Andreas Carlos Meier, Marc Allaart, Magdalena Ardelean, Maxim Arseni, Tim Bösch, Hugues Brenot, Andreea Calcan, Emmanuel Dekemper, Sebastian Donner, Steffen Dörner, Mariana Carmelia Balanica Dragomir, Lucian Georgescu, Anca Nemuc, Doina Nicolae, Gaia Pinardi, Andreas Richter, Adrian Rosu, Thomas Ruhtz, Anja Schönhardt, Dirk Schuettemeyer, Reza Shaiganfar, Kerstin Stebel, Frederik Tack, Sorin Nicolae Vâjâiac, Jeni Vasilescu, Jurgen Vanhamel, Thomas Wagner, and Michel Van Roozendael
Atmos. Meas. Tech., 13, 5513–5535, https://doi.org/10.5194/amt-13-5513-2020, https://doi.org/10.5194/amt-13-5513-2020, 2020
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The AROMAT campaigns took place in Romania in 2014 and 2015. They aimed to test airborne observation systems dedicated to air quality studies and to verify the concept of such campaigns in support of the validation of space-borne atmospheric missions. We show that airborne measurements of NO2 can be valuable for the validation of air quality satellites. For H2CO and SO2, the validation should involve ground-based measurement systems at key locations that the AROMAT measurements help identify.
Yang Wang, Arnoud Apituley, Alkiviadis Bais, Steffen Beirle, Nuria Benavent, Alexander Borovski, Ilya Bruchkouski, Ka Lok Chan, Sebastian Donner, Theano Drosoglou, Henning Finkenzeller, Martina M. Friedrich, Udo Frieß, David Garcia-Nieto, Laura Gómez-Martín, François Hendrick, Andreas Hilboll, Junli Jin, Paul Johnston, Theodore K. Koenig, Karin Kreher, Vinod Kumar, Aleksandra Kyuberis, Johannes Lampel, Cheng Liu, Haoran Liu, Jianzhong Ma, Oleg L. Polyansky, Oleg Postylyakov, Richard Querel, Alfonso Saiz-Lopez, Stefan Schmitt, Xin Tian, Jan-Lukas Tirpitz, Michel Van Roozendael, Rainer Volkamer, Zhuoru Wang, Pinhua Xie, Chengzhi Xing, Jin Xu, Margarita Yela, Chengxin Zhang, and Thomas Wagner
Atmos. Meas. Tech., 13, 5087–5116, https://doi.org/10.5194/amt-13-5087-2020, https://doi.org/10.5194/amt-13-5087-2020, 2020
Marc Schwaerzel, Claudia Emde, Dominik Brunner, Randulph Morales, Thomas Wagner, Alexis Berne, Brigitte Buchmann, and Gerrit Kuhlmann
Atmos. Meas. Tech., 13, 4277–4293, https://doi.org/10.5194/amt-13-4277-2020, https://doi.org/10.5194/amt-13-4277-2020, 2020
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Horizontal homogeneity is often assumed for trace gases remote sensing, although it is not valid where trace gas concentrations have high spatial variability, e.g., in cities. We show the importance of 3D effects for MAX-DOAS and airborne imaging spectrometers using 3D-box air mass factors implemented in the MYSTIC radiative transfer solver. In both cases, 3D information is invaluable for interpreting the measurements, as not considering 3D effects can lead to misinterpretation of measurements.
Steven Compernolle, Tijl Verhoelst, Gaia Pinardi, José Granville, Daan Hubert, Arno Keppens, Sander Niemeijer, Bruno Rino, Alkis Bais, Steffen Beirle, Folkert Boersma, John P. Burrows, Isabelle De Smedt, Henk Eskes, Florence Goutail, François Hendrick, Alba Lorente, Andrea Pazmino, Ankie Piters, Enno Peters, Jean-Pierre Pommereau, Julia Remmers, Andreas Richter, Jos van Geffen, Michel Van Roozendael, Thomas Wagner, and Jean-Christopher Lambert
Atmos. Chem. Phys., 20, 8017–8045, https://doi.org/10.5194/acp-20-8017-2020, https://doi.org/10.5194/acp-20-8017-2020, 2020
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Tropospheric and stratospheric NO2 columns from the OMI QA4ECV NO2 satellite product are validated by comparison with ground-based measurements at 11 sites. The OMI stratospheric column has a small negative bias, and the OMI tropospheric column has a stronger negative bias relative to the ground-based data. Discrepancies are attributed to comparison errors (e.g. difference in horizontal smoothing) and measurement errors (e.g. clouds, aerosols, vertical smoothing and a priori profile assumptions).
Jianzhong Ma, Steffen Dörner, Sebastian Donner, Junli Jin, Siyang Cheng, Junrang Guo, Zhanfeng Zhang, Jianqiong Wang, Peng Liu, Guoqing Zhang, Janis Pukite, Johannes Lampel, and Thomas Wagner
Atmos. Chem. Phys., 20, 6973–6990, https://doi.org/10.5194/acp-20-6973-2020, https://doi.org/10.5194/acp-20-6973-2020, 2020
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We made ground-based MAX-DOAS measurements at the Mt. Waliguan WMO GAW global baseline station (WLG) in the Tibetan Plateau during the years 2012–2015. We retrieve the differential slant column densities (dSCDs) of NO2, SO2, HCHO, and BrO from measured spectra at different elevation angles. Mixing ratios of these trace gases in the background troposphere over WLG are derived based on these dSCDs at a 1° elevation angle and the TRACY-2 radiative transfer model simulations.
Christian Borger, Steffen Beirle, Steffen Dörner, Holger Sihler, and Thomas Wagner
Atmos. Meas. Tech., 13, 2751–2783, https://doi.org/10.5194/amt-13-2751-2020, https://doi.org/10.5194/amt-13-2751-2020, 2020
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We present a total column water vapour (TCWV) retrieval analysing measurements from S-5P/TROPOMI in the visible blue spectral range. The retrieval can well capture the global water vapour distribution with similar sensitivity over the land and ocean and agrees well with various reference data sets within the estimated TCWV uncertainties of typically around 10 %–20 %.
Karin Kreher, Michel Van Roozendael, Francois Hendrick, Arnoud Apituley, Ermioni Dimitropoulou, Udo Frieß, Andreas Richter, Thomas Wagner, Johannes Lampel, Nader Abuhassan, Li Ang, Monica Anguas, Alkis Bais, Nuria Benavent, Tim Bösch, Kristof Bognar, Alexander Borovski, Ilya Bruchkouski, Alexander Cede, Ka Lok Chan, Sebastian Donner, Theano Drosoglou, Caroline Fayt, Henning Finkenzeller, David Garcia-Nieto, Clio Gielen, Laura Gómez-Martín, Nan Hao, Bas Henzing, Jay R. Herman, Christian Hermans, Syedul Hoque, Hitoshi Irie, Junli Jin, Paul Johnston, Junaid Khayyam Butt, Fahim Khokhar, Theodore K. Koenig, Jonas Kuhn, Vinod Kumar, Cheng Liu, Jianzhong Ma, Alexis Merlaud, Abhishek K. Mishra, Moritz Müller, Monica Navarro-Comas, Mareike Ostendorf, Andrea Pazmino, Enno Peters, Gaia Pinardi, Manuel Pinharanda, Ankie Piters, Ulrich Platt, Oleg Postylyakov, Cristina Prados-Roman, Olga Puentedura, Richard Querel, Alfonso Saiz-Lopez, Anja Schönhardt, Stefan F. Schreier, André Seyler, Vinayak Sinha, Elena Spinei, Kimberly Strong, Frederik Tack, Xin Tian, Martin Tiefengraber, Jan-Lukas Tirpitz, Jeroen van Gent, Rainer Volkamer, Mihalis Vrekoussis, Shanshan Wang, Zhuoru Wang, Mark Wenig, Folkard Wittrock, Pinhua H. Xie, Jin Xu, Margarita Yela, Chengxin Zhang, and Xiaoyi Zhao
Atmos. Meas. Tech., 13, 2169–2208, https://doi.org/10.5194/amt-13-2169-2020, https://doi.org/10.5194/amt-13-2169-2020, 2020
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In September 2016, 36 spectrometers from 24 institutes measured a number of key atmospheric pollutants during an instrument intercomparison campaign (CINDI-2) at Cabauw, the Netherlands. Here we report on the outcome of this intercomparison exercise. The three major goals were to characterise the differences between the participating instruments, to define a robust methodology for performance assessment, and to contribute to the harmonisation of the measurement settings and retrieval methods.
Zhuoru Wang, Ka Lok Chan, Klaus-Peter Heue, Adrian Doicu, Thomas Wagner, Robert Holla, and Matthias Wiegner
Atmos. Meas. Tech., 13, 1835–1866, https://doi.org/10.5194/amt-13-1835-2020, https://doi.org/10.5194/amt-13-1835-2020, 2020
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We present a new aerosol profile retrieval algorithm for MAX-DOAS measurements at high-altitude sites and applied to the MAX-DOAS measurements at UFS. The retrieval algorithm is based on a O4 DSCD lookup table which is dedicated to high-altitude MAX-DOAS measurements. The comparison of retrieved aerosol optical depths (AODs) to sun photometer observations shows good agreement with a correlation coefficient (R) of 0.733 and 0.798 at 360 and 477 nm, respectively.
Zoë Y. W. Davis, Udo Frieß, Kevin B. Strawbridge, Monika Aggarwaal, Sabour Baray, Elijah G. Schnitzler, Akshay Lobo, Vitali E. Fioletov, Ihab Abboud, Chris A. McLinden, Jim Whiteway, Megan D. Willis, Alex K. Y. Lee, Jeff Brook, Jason Olfert, Jason O'Brien, Ralf Staebler, Hans D. Osthoff, Cristian Mihele, and Robert McLaren
Atmos. Meas. Tech., 13, 1129–1155, https://doi.org/10.5194/amt-13-1129-2020, https://doi.org/10.5194/amt-13-1129-2020, 2020
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Here, we evaluate a ground-based remote sensing method (MAX-DOAS) for measuring total pollutant loading and vertical profiles of pollution in the lower atmosphere by comparing our method to a variety of other measurement methods (lidar, sunphotometer, active DOAS, and aircraft measurements). Measurements were made in the Athabasca Oil Sands Region in Alberta, Canada. The complex dataset provided a rare opportunity to evaluate the performance of MAX-DOAS under varying atmospheric conditions.
Sebastian Donner, Jonas Kuhn, Michel Van Roozendael, Alkiviadis Bais, Steffen Beirle, Tim Bösch, Kristof Bognar, Ilya Bruchkouski, Ka Lok Chan, Steffen Dörner, Theano Drosoglou, Caroline Fayt, Udo Frieß, François Hendrick, Christian Hermans, Junli Jin, Ang Li, Jianzhong Ma, Enno Peters, Gaia Pinardi, Andreas Richter, Stefan F. Schreier, André Seyler, Kimberly Strong, Jan-Lukas Tirpitz, Yang Wang, Pinhua Xie, Jin Xu, Xiaoyi Zhao, and Thomas Wagner
Atmos. Meas. Tech., 13, 685–712, https://doi.org/10.5194/amt-13-685-2020, https://doi.org/10.5194/amt-13-685-2020, 2020
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The calibration of the elevation angles of MAX-DOAS instruments is important for the correct interpretation of such MAX-DOAS measurements. We present and evaluate different methods for the elevation calibration of MAX-DOAS instruments which were applied during the CINDI-2 field campaign.
Ulrich Platt and Jonas Kuhn
Atmos. Meas. Tech., 12, 6259–6272, https://doi.org/10.5194/amt-12-6259-2019, https://doi.org/10.5194/amt-12-6259-2019, 2019
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Measurements of atmospheric trace gases by absorption spectroscopy are frequently supported by recording the amount of trace gas in absorption cells. These are typically small glass (or quartz) cylinders containing the gas to be studied. Here we show in the example of NO2-absorption cells that the effective amount of gas seen by the instrument can deviate greatly from expected values (by orders of magnitude in severe cases). Some suggestions for improving the situation are discussed.
Maximilian Herrmann, Le Cao, Holger Sihler, Ulrich Platt, and Eva Gutheil
Atmos. Chem. Phys., 19, 10161–10190, https://doi.org/10.5194/acp-19-10161-2019, https://doi.org/10.5194/acp-19-10161-2019, 2019
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The oscillations of tropospheric ODEs in the Arctic spring is studied numerically. After the termination of an ODE, the reactive bromine is deposited onto aerosols/the snow surface, and the ozone may regenerate. The replenished ozone is available for the next autocatalytic bromine release, leading to the oscillation of an ODE. Its dependence on the NOx mixing ratio, the inversion layer strength, the ambient temperature, the aerosol density, and the solar radiation is investigated.
Jan-Marcus Nasse, Philipp G. Eger, Denis Pöhler, Stefan Schmitt, Udo Frieß, and Ulrich Platt
Atmos. Meas. Tech., 12, 4149–4169, https://doi.org/10.5194/amt-12-4149-2019, https://doi.org/10.5194/amt-12-4149-2019, 2019
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We present several changes to the setup of long-path differential optical absorption spectroscopy (LP-DOAS) instruments, including the application of a laser-driven light source, a modified coupling of the measurement signal between components, improved stray-light suppression, and better signal homogenization measures. These changes reduce detection limits of typical trace-gas species by a factor of 3–4 compared to previous setups and enable automated long-term observations in Antarctica.
Martin Horbanski, Denis Pöhler, Johannes Lampel, and Ulrich Platt
Atmos. Meas. Tech., 12, 3365–3381, https://doi.org/10.5194/amt-12-3365-2019, https://doi.org/10.5194/amt-12-3365-2019, 2019
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ICAD allows a precise in situ measurement of gases like NO2 in a relatively simple and compact setup. The main advantage in comparison to most other optical methods is that it does not require a stable total light intensity. This allows a simpler and mobile instrument setup and additionally it features no observed cross-interferences. We validated the high quality for an ICAD NO2 instrument in different inter-comparisons with a detection limit of 0.02 ppbv.
Florian Dinger, Stefan Bredemeyer, Santiago Arellano, Nicole Bobrowski, Ulrich Platt, and Thomas Wagner
Solid Earth, 10, 725–740, https://doi.org/10.5194/se-10-725-2019, https://doi.org/10.5194/se-10-725-2019, 2019
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Evidence for tidal impacts on volcanism have been gathered by numerous empirical studies. This paper elucidates whether a causal link from the tidal forces to a variation in the volcanic degassing can be traced analytically. We model the response of a simplified magmatic system to the local tidal gravity variations, find that the tide-induced dynamics may significantly alter the bubble coalescence rate, and discuss the consequences for volcanic degassing behaviour.
Thomas Wagner, Steffen Beirle, Nuria Benavent, Tim Bösch, Ka Lok Chan, Sebastian Donner, Steffen Dörner, Caroline Fayt, Udo Frieß, David García-Nieto, Clio Gielen, David González-Bartolome, Laura Gomez, François Hendrick, Bas Henzing, Jun Li Jin, Johannes Lampel, Jianzhong Ma, Kornelia Mies, Mónica Navarro, Enno Peters, Gaia Pinardi, Olga Puentedura, Janis Puķīte, Julia Remmers, Andreas Richter, Alfonso Saiz-Lopez, Reza Shaiganfar, Holger Sihler, Michel Van Roozendael, Yang Wang, and Margarita Yela
Atmos. Meas. Tech., 12, 2745–2817, https://doi.org/10.5194/amt-12-2745-2019, https://doi.org/10.5194/amt-12-2745-2019, 2019
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In this study the consistency between MAX-DOAS measurements and radiative transfer simulations of the atmospheric O4 absorption is investigated. The study is based on measurements (2 selected days during the MADCAT campaign) as well as synthetic spectra. The uncertainties of all relevant aspects (spectral retrieval and radiative transfer simulations) are quantified. For one of the selected days, measurements and simulations do not agree within their uncertainties.
Yang Wang, Steffen Dörner, Sebastian Donner, Sebastian Böhnke, Isabelle De Smedt, Russell R. Dickerson, Zipeng Dong, Hao He, Zhanqing Li, Zhengqiang Li, Donghui Li, Dong Liu, Xinrong Ren, Nicolas Theys, Yuying Wang, Yang Wang, Zhenzhu Wang, Hua Xu, Jiwei Xu, and Thomas Wagner
Atmos. Chem. Phys., 19, 5417–5449, https://doi.org/10.5194/acp-19-5417-2019, https://doi.org/10.5194/acp-19-5417-2019, 2019
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A MAX-DOAS instrument was operated to derive tropospheric vertical profiles of NO2, SO2, HONO, HCHO, CHOCHO and aerosols in the central western North China Plain in May and June 2016. The MAX-DOAS results are verified by comparisons with a collocated Raman lidar, overpass aircraft measurements, a sun photometer and in situ measurements. The contributions of regional transports and local emissions to the pollutants are evaluated based on case studies and statistic analysis.
Udo Frieß, Steffen Beirle, Leonardo Alvarado Bonilla, Tim Bösch, Martina M. Friedrich, François Hendrick, Ankie Piters, Andreas Richter, Michel van Roozendael, Vladimir V. Rozanov, Elena Spinei, Jan-Lukas Tirpitz, Tim Vlemmix, Thomas Wagner, and Yang Wang
Atmos. Meas. Tech., 12, 2155–2181, https://doi.org/10.5194/amt-12-2155-2019, https://doi.org/10.5194/amt-12-2155-2019, 2019
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Multi-axis differential optical absorption spectroscopy (MAX-DOAS) is a widely used measurement technique for the detection of a variety of atmospheric trace gases. It enables the retrieval of aerosol and trace gas vertical profiles in the atmospheric boundary layer using appropriate retrieval algorithms. In this study, the ability of eight profile retrieval algorithms to reconstruct vertical profiles is assessed on the basis of synthetic measurements.
Steffen Beirle, Steffen Dörner, Sebastian Donner, Julia Remmers, Yang Wang, and Thomas Wagner
Atmos. Meas. Tech., 12, 1785–1806, https://doi.org/10.5194/amt-12-1785-2019, https://doi.org/10.5194/amt-12-1785-2019, 2019
Umar Javed, Dagmar Kubistin, Monica Martinez, Jan Pollmann, Markus Rudolf, Uwe Parchatka, Andreas Reiffs, Jim Thieser, Gerhard Schuster, Martin Horbanski, Denis Pöhler, John N. Crowley, Horst Fischer, Jos Lelieveld, and Hartwig Harder
Atmos. Meas. Tech., 12, 1461–1481, https://doi.org/10.5194/amt-12-1461-2019, https://doi.org/10.5194/amt-12-1461-2019, 2019
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Nitrogen dioxide (NO2) affects the concentration of key species like ozone, hydroxyl radical, and nitrate radical in the atmosphere. In situ, direct, and interference-free NO2 measurements are important for validating our understanding of NOx chemistry related to ozone formation and the radical loss process. This article describes the important features and performance of a newly developed NO2 instrument during a field intercomparison.
Jonas Kuhn, Ulrich Platt, Nicole Bobrowski, and Thomas Wagner
Atmos. Meas. Tech., 12, 735–747, https://doi.org/10.5194/amt-12-735-2019, https://doi.org/10.5194/amt-12-735-2019, 2019
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We study a novel remote-sensing technique for atmospheric trace gases absorbing in the UV and visible spectral range. Using Fabry–Perot interferometers with a spectral transmission matched to the trace gas's spectral absorption allows for imaging trace gases with high sensitivity and selectivity. The thereby achieved high spatio-temporal resolution enables the study of small-scale and dynamic processes in the atmosphere. We present sample calculations and a proof-of-concept study.
Mengyao Liu, Jintai Lin, K. Folkert Boersma, Gaia Pinardi, Yang Wang, Julien Chimot, Thomas Wagner, Pinhua Xie, Henk Eskes, Michel Van Roozendael, François Hendrick, Pucai Wang, Ting Wang, Yingying Yan, Lulu Chen, and Ruijing Ni
Atmos. Meas. Tech., 12, 1–21, https://doi.org/10.5194/amt-12-1-2019, https://doi.org/10.5194/amt-12-1-2019, 2019
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China has become the world’s largest emitter of NOx, which mainly comes from vehicle exhaust, power plants, etc. However, there are no official ground-based measurements before 2013, so satellites have been widely used to monitor and analyze NOx pollution here. Aerosol is the key factor influencing the accuracy of the satellite NOx product. Our study provides a more accurate way to account for aerosol's influence compared to current widely used products.
Tim Bösch, Vladimir Rozanov, Andreas Richter, Enno Peters, Alexei Rozanov, Folkard Wittrock, Alexis Merlaud, Johannes Lampel, Stefan Schmitt, Marijn de Haij, Stijn Berkhout, Bas Henzing, Arnoud Apituley, Mirjam den Hoed, Jan Vonk, Martin Tiefengraber, Moritz Müller, and John Philip Burrows
Atmos. Meas. Tech., 11, 6833–6859, https://doi.org/10.5194/amt-11-6833-2018, https://doi.org/10.5194/amt-11-6833-2018, 2018
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A new MAX-DOAS profiling algorithm for aerosols and trace
gases was developed.
The performance of this novel algorithm was tested with the help of
synthetic data and measurements from the CINDI-2 campaign in Cabauw, the
Netherlands, in 2016.
Ying Zhu, Ka Lok Chan, Yun Fat Lam, Martin Horbanski, Denis Pöhler, Johannes Boll, Ivo Lipkowitsch, Sheng Ye, and Mark Wenig
Atmos. Meas. Tech., 11, 6719–6734, https://doi.org/10.5194/amt-11-6719-2018, https://doi.org/10.5194/amt-11-6719-2018, 2018
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The paper presents an investigation of spatio-temporal variability of street-level NO2 in Hong Kong using mobile cavity-enhanced differential optical absorption spectroscopy (DOAS) and long-path DOAS. Measurements were conducted in December 2010 and March 2017. A significant decreasing trend in on-road NO2 was found by comparing measurements taken in 2010 and 2017. Influences of changes in bus companies' operation strategies can also be observed from the measured NO2 concentration maps.
K. Folkert Boersma, Henk J. Eskes, Andreas Richter, Isabelle De Smedt, Alba Lorente, Steffen Beirle, Jos H. G. M. van Geffen, Marina Zara, Enno Peters, Michel Van Roozendael, Thomas Wagner, Joannes D. Maasakkers, Ronald J. van der A, Joanne Nightingale, Anne De Rudder, Hitoshi Irie, Gaia Pinardi, Jean-Christopher Lambert, and Steven C. Compernolle
Atmos. Meas. Tech., 11, 6651–6678, https://doi.org/10.5194/amt-11-6651-2018, https://doi.org/10.5194/amt-11-6651-2018, 2018
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This paper describes a new, improved data record of 22+ years of coherent nitrogen dioxide (NO2) pollution measurements from different satellite instruments. Our work helps to ensure that climate data are of sufficient quality to draw reliable conclusions and shape decisions. It shows how dedicated intercomparisons of retrieval sub-steps have led to improved NO2 measurements from the GOME, SCIAMACHY, GOME-2(A), and OMI sensors, and how quality assurance of the new data product is achieved.
Roeland Van Malderen, Eric Pottiaux, Gintautas Stankunavicius, Steffen Beirle, Thomas Wagner, Hugues Brenot, and Carine Bruyninx
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2018-1170, https://doi.org/10.5194/acp-2018-1170, 2018
Revised manuscript not accepted
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The study investigates the long-term time variability of the integrated water vapour retrieved by different techniques (GPS, UV/VIS satellites and numerical weather prediction reanalyses) for a global dataset of almost 120 sites and for the time period 1995–2010. A stepwise multiple linear regression technique is applied to ascribe the time variability of integrated water vapour to surface measurements at the sites, but also using teleconnection patterns or climate/oceanic indices.
Robert G. Ryan, Steve Rhodes, Matthew Tully, Stephen Wilson, Nicholas Jones, Udo Frieß, and Robyn Schofield
Atmos. Chem. Phys., 18, 13969–13985, https://doi.org/10.5194/acp-18-13969-2018, https://doi.org/10.5194/acp-18-13969-2018, 2018
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Nitrous acid (HONO) plays a crucial role in the self-cleansing capacity of the atmosphere but its formation mechanisms and spatial distributions are not well understood. This paper presents spectroscopic measurements of HONO, NO2 and aerosol measurements from Melbourne, Australia. HONO levels are at a maximum in the middle of the day, which is unprecedented for an urban area, and these measurements provide evidence for the existence of a strong ground-based, daytime nitrogen oxide source.
Jorge Saturno, Florian Ditas, Marloes Penning de Vries, Bruna A. Holanda, Mira L. Pöhlker, Samara Carbone, David Walter, Nicole Bobrowski, Joel Brito, Xuguang Chi, Alexandra Gutmann, Isabella Hrabe de Angelis, Luiz A. T. Machado, Daniel Moran-Zuloaga, Julian Rüdiger, Johannes Schneider, Christiane Schulz, Qiaoqiao Wang, Manfred Wendisch, Paulo Artaxo, Thomas Wagner, Ulrich Pöschl, Meinrat O. Andreae, and Christopher Pöhlker
Atmos. Chem. Phys., 18, 10391–10405, https://doi.org/10.5194/acp-18-10391-2018, https://doi.org/10.5194/acp-18-10391-2018, 2018
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This study uses satellite observations to track volcanic emissions in eastern Congo and their subsequent transport across the Atlantic Ocean into the Amazon Basin. Aircraft and ground-based observations are used to characterize the influence of volcanogenic aerosol on the chemical and microphysical properties of Amazonian aerosols. Further, this work is an illustrative example of the conditions and dynamics driving the transatlantic transport of African emissions to South America.
Marina Zara, K. Folkert Boersma, Isabelle De Smedt, Andreas Richter, Enno Peters, Jos H. G. M. van Geffen, Steffen Beirle, Thomas Wagner, Michel Van Roozendael, Sergey Marchenko, Lok N. Lamsal, and Henk J. Eskes
Atmos. Meas. Tech., 11, 4033–4058, https://doi.org/10.5194/amt-11-4033-2018, https://doi.org/10.5194/amt-11-4033-2018, 2018
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Nitrogen dioxide and formaldehyde satellite data are used for air quality and climate studies. We quantify and characterise slant column uncertainties from different research groups. Our evaluation is motivated by recently improved techniques and by a desire to provide fully traceable uncertainty budget for climate records generated within the QA4ECV project. The improved slant columns are in agreement but with substantial differences in the reported uncertainties between groups and instruments.
Stephen Broccardo, Klaus-Peter Heue, David Walter, Christian Meyer, Alexander Kokhanovsky, Ronald van der A, Stuart Piketh, Kristy Langerman, and Ulrich Platt
Atmos. Meas. Tech., 11, 2797–2819, https://doi.org/10.5194/amt-11-2797-2018, https://doi.org/10.5194/amt-11-2797-2018, 2018
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Measurements of nitrogen dioxide, known to originate from industrial and automotive combustion sources, have been made from space for two decades. Successive generations of instrument bring improvements in ground-pixel resolution; however features in the atmosphere are known to be smaller than what the satellites can resolve. Measurements of urban and industrial areas using a high-resolution airborne instrument allow the impact of the satellite's relatively low resolution to be evaluated.
Isabelle De Smedt, Nicolas Theys, Huan Yu, Thomas Danckaert, Christophe Lerot, Steven Compernolle, Michel Van Roozendael, Andreas Richter, Andreas Hilboll, Enno Peters, Mattia Pedergnana, Diego Loyola, Steffen Beirle, Thomas Wagner, Henk Eskes, Jos van Geffen, Klaas Folkert Boersma, and Pepijn Veefkind
Atmos. Meas. Tech., 11, 2395–2426, https://doi.org/10.5194/amt-11-2395-2018, https://doi.org/10.5194/amt-11-2395-2018, 2018
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This paper introduces the formaldehyde (HCHO) tropospheric vertical column retrieval algorithm implemented in the TROPOMI/Sentinel-5 Precursor operational processor, and comprehensively describes its various retrieval steps. Furthermore, algorithmic improvements developed in the framework of the EU FP7-project QA4ECV are described for future updates of the processor. Detailed error estimates are discussed in the light of Copernicus user requirements and needs for validation are highlighted.
David W. T. Griffith, Denis Pöhler, Stefan Schmitt, Samuel Hammer, Sanam N. Vardag, and Ulrich Platt
Atmos. Meas. Tech., 11, 1549–1563, https://doi.org/10.5194/amt-11-1549-2018, https://doi.org/10.5194/amt-11-1549-2018, 2018
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Measurements of atmospheric trace gases over an open path complement in situ measurements by spatial averaging. This paper describes the first open-path measurements of CO2, CH4 and other trace gases by near-infrared Fourier transform spectroscopy. The measurements were made in Heidelberg, Germany, for 4 months in 2014 over a 1.5 km path and compared to in situ measurements made at one end of the path. The experiment setup and methods (and the comparisons of open path to in situ) are described.
Steffen Beirle, Johannes Lampel, Yang Wang, Kornelia Mies, Steffen Dörner, Margherita Grossi, Diego Loyola, Angelika Dehn, Anja Danielczok, Marc Schröder, and Thomas Wagner
Earth Syst. Sci. Data, 10, 449–468, https://doi.org/10.5194/essd-10-449-2018, https://doi.org/10.5194/essd-10-449-2018, 2018
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We present time series of the global distribution of water vapor over more than 2 decades based on satellite measurements from different sensors. A particular focus is the consistency amongst the different sensors to avoid jumps from one instrument to another. This is reached by applying robust and simple retrieval settings consistently. The resulting
Climateproduct allows the study of the temporal evolution of water vapor over the last 20 years on a global scale.
Florian Dinger, Nicole Bobrowski, Simon Warnach, Stefan Bredemeyer, Silvana Hidalgo, Santiago Arellano, Bo Galle, Ulrich Platt, and Thomas Wagner
Solid Earth, 9, 247–266, https://doi.org/10.5194/se-9-247-2018, https://doi.org/10.5194/se-9-247-2018, 2018
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We monitored the bromine monoxide-to-sulfur dioxide molar ratio in the effusive gas plume of Cotopaxi volcano in order to gain insight into the geological processes which control the pressure regime of the volcanic system. We observed a conspicuous periodic pattern with a periodicity of about 2 weeks, which significantly correlates with the Earth tidal forcing. Our results support a possible Earth tidal impact on volcanic activity, in particular for the Cotopaxi eruption 2015.
Christoph Kleinschmitt, Olivier Boucher, and Ulrich Platt
Atmos. Chem. Phys., 18, 2769–2786, https://doi.org/10.5194/acp-18-2769-2018, https://doi.org/10.5194/acp-18-2769-2018, 2018
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We use a state-of-the-art stratospheric aerosol model to study geoengineering through stratospheric sulfur injections. We find that the efficiency may decrease more drastically for larger injections than previously estimated and that injections at higher altitude are not more effective. This study may provide additional evidence that this proposed geoengineering technique is still more complicated, probably less effective, and may implicate stronger side effects than initially thought.
Johannes Lampel, Yang Wang, Andreas Hilboll, Steffen Beirle, Holger Sihler, Janis Puķīte, Ulrich Platt, and Thomas Wagner
Atmos. Meas. Tech., 10, 4819–4831, https://doi.org/10.5194/amt-10-4819-2017, https://doi.org/10.5194/amt-10-4819-2017, 2017
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Experience of differential atmospheric absorption spectroscopy (DOAS) shows that a spectral shift between measurement and reference spectrum is frequently required in order to achieve optimal fit results. The shift is often attributed to temporal instabilities of the instrument but implicitly solved the problem of the tilt effect discussed in this paper. The tilt effect results from the finite resolution of the measurements and amounts to 2 pm for the example data set.
Yang Wang, Steffen Beirle, Francois Hendrick, Andreas Hilboll, Junli Jin, Aleksandra A. Kyuberis, Johannes Lampel, Ang Li, Yuhan Luo, Lorenzo Lodi, Jianzhong Ma, Monica Navarro, Ivan Ortega, Enno Peters, Oleg L. Polyansky, Julia Remmers, Andreas Richter, Olga Puentedura, Michel Van Roozendael, André Seyler, Jonathan Tennyson, Rainer Volkamer, Pinhua Xie, Nikolai F. Zobov, and Thomas Wagner
Atmos. Meas. Tech., 10, 3719–3742, https://doi.org/10.5194/amt-10-3719-2017, https://doi.org/10.5194/amt-10-3719-2017, 2017
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Slant column densities of nitrous acid (HONO) derived from different MAX-DOAS instruments and retrieval software are systematically compared for the first time during the Multi Axis DOAS – Comparison campaign for Aerosols and Trace gases (MAD-CAT) campaign held at MPIC in Mainz, Germany, from June to October 2013. Through the inter-comparisons and sensitivity studies we quantified the uncertainties in the DOAS fits of HONO from different sources and concluded a recommended setting.
Christoph Kleinschmitt, Olivier Boucher, Slimane Bekki, François Lott, and Ulrich Platt
Geosci. Model Dev., 10, 3359–3378, https://doi.org/10.5194/gmd-10-3359-2017, https://doi.org/10.5194/gmd-10-3359-2017, 2017
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Stratospheric aerosols play an important role in the climate system by affecting the Earth's radiative budget. In this article we present the newly developed LMDZ-S3A model and assess its performance against observations in periods of low and high aerosol loading. The model may serve as a tool to study the climate impacts of volcanic eruptions, as well as the deliberate injection of aerosols into the stratosphere, which has been proposed as a method of geoengineering to abate global warming.
William R. Simpson, Peter K. Peterson, Udo Frieß, Holger Sihler, Johannes Lampel, Ulrich Platt, Chris Moore, Kerri Pratt, Paul Shepson, John Halfacre, and Son V. Nghiem
Atmos. Chem. Phys., 17, 9291–9309, https://doi.org/10.5194/acp-17-9291-2017, https://doi.org/10.5194/acp-17-9291-2017, 2017
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We investigated Arctic atmospheric bromine chemistry during March–April 2012 to improve understanding of the role of sea ice and cracks in sea ice (leads) in this phenomenon. We find that leads vertically redistribute reactive bromine but that open/re-freezing leads are not major direct reactive halogen sources. Surface ozone depletion affects the vertical distribution and amount of reactive halogens, and aerosol particles are necessary but not sufficient to maintain reactive bromine aloft.
Reza Shaiganfar, Steffen Beirle, Hugo Denier van der Gon, Sander Jonkers, Jeroen Kuenen, Herve Petetin, Qijie Zhang, Matthias Beekmann, and Thomas Wagner
Atmos. Chem. Phys., 17, 7853–7890, https://doi.org/10.5194/acp-17-7853-2017, https://doi.org/10.5194/acp-17-7853-2017, 2017
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We determine NOx emissions for Paris in summer 2009 and winter 2009/2010 by combining car MAX-DOAS measurements of NO2 with wind fields. We compare the results with simulations from the CHIMERE model. We derive daily average NOx emissions for Paris of 4.0 × 1025 molecules s−1 for summer and of 6.9 × 1025 molecules s−1 in winter. These values are a factor of about 1.4 and 2.0 larger than the corresponding emissions in the MACC-III emission inventory.
Peter K. Peterson, Denis Pöhler, Holger Sihler, Johannes Zielcke, Stephan General, Udo Frieß, Ulrich Platt, William R. Simpson, Son V. Nghiem, Paul B. Shepson, Brian H. Stirm, Suresh Dhaniyala, Thomas Wagner, Dana R. Caulton, Jose D. Fuentes, and Kerri A. Pratt
Atmos. Chem. Phys., 17, 7567–7579, https://doi.org/10.5194/acp-17-7567-2017, https://doi.org/10.5194/acp-17-7567-2017, 2017
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High-spatial-resolution aircraft measurements in the Arctic showed the sustained transport of reactive bromine in a lofted layer via heterogeneous reactions on aerosol particles. This process provides an explanation for free tropospheric reactive bromine and the significant spatial extent of satellite-observed bromine monoxide. The knowledge gained herein improves our understanding of the fate and transport of atmospheric pollutants in the Arctic.
Andreas Carlos Meier, Anja Schönhardt, Tim Bösch, Andreas Richter, André Seyler, Thomas Ruhtz, Daniel-Eduard Constantin, Reza Shaiganfar, Thomas Wagner, Alexis Merlaud, Michel Van Roozendael, Livio Belegante, Doina Nicolae, Lucian Georgescu, and John Philip Burrows
Atmos. Meas. Tech., 10, 1831–1857, https://doi.org/10.5194/amt-10-1831-2017, https://doi.org/10.5194/amt-10-1831-2017, 2017
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We present airborne remote sensing measurements of NO2 in the urban area of Bucharest. NO2 is a harmful pollutant, which is emitted in combustion processes. The measurements presented here enable the creation of maps, showing the horizontal NO2 distribution across the whole city within a relatively short time window of 1.5 h. These data provide new insight into urban pollution levels and their spatial distribution.
Yang Wang, Steffen Beirle, Johannes Lampel, Mariliza Koukouli, Isabelle De Smedt, Nicolas Theys, Ang Li, Dexia Wu, Pinhua Xie, Cheng Liu, Michel Van Roozendael, Trissevgeni Stavrakou, Jean-François Müller, and Thomas Wagner
Atmos. Chem. Phys., 17, 5007–5033, https://doi.org/10.5194/acp-17-5007-2017, https://doi.org/10.5194/acp-17-5007-2017, 2017
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A long-term MAX-DOAS measurement from 2011 to 2014 was operated in Wuxi, part of the most industrialized area of the Yangtze River delta region of China. The tropospheric VCDs and vertical profiles of NO2, SO2 and HCHO derived from the MAX-DOAS are used to validate the products derived from OMI and GOME-2A/B by different scientific teams (daily- and bimonthly-averaged data). We investigate the effects of clouds, aerosols and a priori profile shapes on satellite retrievals of tropospheric VCDs.
Angelika Klein, Peter Lübcke, Nicole Bobrowski, Jonas Kuhn, and Ulrich Platt
Atmos. Meas. Tech., 10, 979–987, https://doi.org/10.5194/amt-10-979-2017, https://doi.org/10.5194/amt-10-979-2017, 2017
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While measuring sulfur dioxide fluxes in volcanic plumes with a UV-sensitive camera, the wind direction can influence the retrieved fluxes. If the volcanic plume is tilted in the field of view of the camera, it can lead to over- or underestimations of the determined fluxes. This paper presents a method to deal with such a circumstance. Additionally, it provides the possibility to determine the wind direction of the plume directly from the image time series themselves.
Enno Peters, Gaia Pinardi, André Seyler, Andreas Richter, Folkard Wittrock, Tim Bösch, Michel Van Roozendael, François Hendrick, Theano Drosoglou, Alkiviadis F. Bais, Yugo Kanaya, Xiaoyi Zhao, Kimberly Strong, Johannes Lampel, Rainer Volkamer, Theodore Koenig, Ivan Ortega, Olga Puentedura, Mónica Navarro-Comas, Laura Gómez, Margarita Yela González, Ankie Piters, Julia Remmers, Yang Wang, Thomas Wagner, Shanshan Wang, Alfonso Saiz-Lopez, David García-Nieto, Carlos A. Cuevas, Nuria Benavent, Richard Querel, Paul Johnston, Oleg Postylyakov, Alexander Borovski, Alexander Elokhov, Ilya Bruchkouski, Haoran Liu, Cheng Liu, Qianqian Hong, Claudia Rivera, Michel Grutter, Wolfgang Stremme, M. Fahim Khokhar, Junaid Khayyam, and John P. Burrows
Atmos. Meas. Tech., 10, 955–978, https://doi.org/10.5194/amt-10-955-2017, https://doi.org/10.5194/amt-10-955-2017, 2017
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This work is about harmonization of differential optical absorption spectroscopy retrieval codes, which is a remote sensing technique widely used to derive atmospheric trace gas amounts. The study is based on ground-based measurements performed during the Multi-Axis DOAS Comparison campaign for Aerosols and Trace gases (MAD-CAT) in Mainz, Germany, in summer 2013. In total, 17 international groups working in the field of the DOAS technique participated in this study.
Holger Sihler, Peter Lübcke, Rüdiger Lang, Steffen Beirle, Martin de Graaf, Christoph Hörmann, Johannes Lampel, Marloes Penning de Vries, Julia Remmers, Ed Trollope, Yang Wang, and Thomas Wagner
Atmos. Meas. Tech., 10, 881–903, https://doi.org/10.5194/amt-10-881-2017, https://doi.org/10.5194/amt-10-881-2017, 2017
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This paper presents the independent and simple IFR method to retrieve the FOV of an instrument, i.e. the two-dimensional sensitivity distribution. IFR relies on correlated measurements featuring a higher spatial resolution and was applied to two satellite instruments, GOME-2 and OMI, and a DOAS instrument integrated in an SO2 camera. Our results confirm the commonly applied FOV distributions. IFR is applicable for verification exercises as well as degradation monitoring in the field.
Alba Lorente, K. Folkert Boersma, Huan Yu, Steffen Dörner, Andreas Hilboll, Andreas Richter, Mengyao Liu, Lok N. Lamsal, Michael Barkley, Isabelle De Smedt, Michel Van Roozendael, Yang Wang, Thomas Wagner, Steffen Beirle, Jin-Tai Lin, Nickolay Krotkov, Piet Stammes, Ping Wang, Henk J. Eskes, and Maarten Krol
Atmos. Meas. Tech., 10, 759–782, https://doi.org/10.5194/amt-10-759-2017, https://doi.org/10.5194/amt-10-759-2017, 2017
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Choices and assumptions made to represent the state of the atmosphere introduce an uncertainty of 42 % in the air mass factor calculation in trace gas satellite retrievals in polluted regions. The AMF strongly depends on the choice of a priori trace gas profile, surface albedo data set and the correction method to account for clouds and aerosols. We call for well-designed validation exercises focusing on situations when AMF structural uncertainty has the highest impact on satellite retrievals.
Steffen Beirle, Johannes Lampel, Christophe Lerot, Holger Sihler, and Thomas Wagner
Atmos. Meas. Tech., 10, 581–598, https://doi.org/10.5194/amt-10-581-2017, https://doi.org/10.5194/amt-10-581-2017, 2017
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We propose to parameterize the instrumental spectral response function (ISRF) as a "super-Gaussian", which can reproduce a variety of shapes, from point-hat to boxcar shape, by just adding one parameter to the "classical" Gaussian.
In addition, the super-Gaussian allows for a straightforward parametrization of the effect of ISRF changes.
Yang Wang, Johannes Lampel, Pinhua Xie, Steffen Beirle, Ang Li, Dexia Wu, and Thomas Wagner
Atmos. Chem. Phys., 17, 2189–2215, https://doi.org/10.5194/acp-17-2189-2017, https://doi.org/10.5194/acp-17-2189-2017, 2017
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The air pollution in the Yangtze River delta (YRD), the largest economic region in China, threatens the health of the inhabitants in this region. A long-term MAX-DOAS observation in Wuxi, China (belonging to YRD), is used to characterize vertical distributions (VD) of the aerosols and the precursor trace gases in the boundary to identify the dominating sources. The results are valuable for further validation of satellite products and chemical transport modelings.
Nga Lee Ng, Steven S. Brown, Alexander T. Archibald, Elliot Atlas, Ronald C. Cohen, John N. Crowley, Douglas A. Day, Neil M. Donahue, Juliane L. Fry, Hendrik Fuchs, Robert J. Griffin, Marcelo I. Guzman, Hartmut Herrmann, Alma Hodzic, Yoshiteru Iinuma, José L. Jimenez, Astrid Kiendler-Scharr, Ben H. Lee, Deborah J. Luecken, Jingqiu Mao, Robert McLaren, Anke Mutzel, Hans D. Osthoff, Bin Ouyang, Benedicte Picquet-Varrault, Ulrich Platt, Havala O. T. Pye, Yinon Rudich, Rebecca H. Schwantes, Manabu Shiraiwa, Jochen Stutz, Joel A. Thornton, Andreas Tilgner, Brent J. Williams, and Rahul A. Zaveri
Atmos. Chem. Phys., 17, 2103–2162, https://doi.org/10.5194/acp-17-2103-2017, https://doi.org/10.5194/acp-17-2103-2017, 2017
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Oxidation of biogenic volatile organic compounds by NO3 is an important interaction between anthropogenic
and natural emissions. This review results from a June 2015 workshop and includes the recent literature
on kinetics, mechanisms, organic aerosol yields, and heterogeneous chemistry; advances in analytical
instrumentation; the current state NO3-BVOC chemistry in atmospheric models; and critical needs for
future research in modeling, field observations, and laboratory studies.
Johannes Lampel, Denis Pöhler, Oleg L. Polyansky, Aleksandra A. Kyuberis, Nikolai F. Zobov, Jonathan Tennyson, Lorenzo Lodi, Udo Frieß, Yang Wang, Steffen Beirle, Ulrich Platt, and Thomas Wagner
Atmos. Chem. Phys., 17, 1271–1295, https://doi.org/10.5194/acp-17-1271-2017, https://doi.org/10.5194/acp-17-1271-2017, 2017
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Water vapour is known to absorb radiation from the microwave region to the blue part of the visible spectrum.
Ab initio approaches to model individual absorption lines of the gaseous water molecule predict absorption lines
until its dissociation limit at 243 nm.
We present first evidence of water vapour absorption near 363 nm from field measurements using data
from multi-axis differential optical absorption spectroscopy (MAX-DOAS) and long-path (LP)-DOAS measurements.
Nicolas Theys, Isabelle De Smedt, Huan Yu, Thomas Danckaert, Jeroen van Gent, Christoph Hörmann, Thomas Wagner, Pascal Hedelt, Heiko Bauer, Fabian Romahn, Mattia Pedergnana, Diego Loyola, and Michel Van Roozendael
Atmos. Meas. Tech., 10, 119–153, https://doi.org/10.5194/amt-10-119-2017, https://doi.org/10.5194/amt-10-119-2017, 2017
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This paper provides a thorough description of the algorithm to retrieve SO2 columns from TROPOMI/Sentinel-5 Precursor measurements. The different algorithmic steps including error analysis are detailed. Scientific verification of the algorithm and validation needs are also discussed.
Peter Lübcke, Johannes Lampel, Santiago Arellano, Nicole Bobrowski, Florian Dinger, Bo Galle, Gustavo Garzón, Silvana Hidalgo, Zoraida Chacón Ortiz, Leif Vogel, Simon Warnach, and Ulrich Platt
Atmos. Meas. Tech., 9, 5677–5698, https://doi.org/10.5194/amt-9-5677-2016, https://doi.org/10.5194/amt-9-5677-2016, 2016
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We evaluated spectra from a scanning spectrometer network for the monitoring of volcanic gas emissions using a modelled background spectrum. Statistical methods were applied in order to improve the quality of the spectroscopic evaluation. We used this technique to assess the robustness of standard retrievals at two volcanos: Nevado del Ruiz (Colombia) and Tungurahua (Ecuador).
Christoph Hörmann, Holger Sihler, Steffen Beirle, Marloes Penning de Vries, Ulrich Platt, and Thomas Wagner
Atmos. Chem. Phys., 16, 13015–13034, https://doi.org/10.5194/acp-16-13015-2016, https://doi.org/10.5194/acp-16-13015-2016, 2016
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We present 10 years of bromine monoxide (BrO) satellite observations by the Ozone Monitoring Instrument (OMI) over the Rann of Kutch salt marsh. The measurements reveal a typical seasonal cycle of BrO with maximum concentrations during April/May. The results indicate that the Rann of Kutch is probably one of the strongest natural point sources of reactive bromine compounds outside the polar regions and is thought to have a significant impact on local and regional ozone chemistry.
Shanshan Wang, Carlos A. Cuevas, Udo Frieß, and Alfonso Saiz-Lopez
Atmos. Meas. Tech., 9, 5089–5101, https://doi.org/10.5194/amt-9-5089-2016, https://doi.org/10.5194/amt-9-5089-2016, 2016
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Multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements were performed in the urban environment of Madrid, Spain, where Sahara dust intrusion sometimes occurs. The study shows a high performances in the retrieval of aerosol optical depth, the surface extinction coefficient and an elevated layer during dust episodes, validated by AERONET in situ and modeling data. It is essential to capture the extinction properties of both local aerosol and Saharan dust.
Helmke Hepach, Birgit Quack, Susann Tegtmeier, Anja Engel, Astrid Bracher, Steffen Fuhlbrügge, Luisa Galgani, Elliot L. Atlas, Johannes Lampel, Udo Frieß, and Kirstin Krüger
Atmos. Chem. Phys., 16, 12219–12237, https://doi.org/10.5194/acp-16-12219-2016, https://doi.org/10.5194/acp-16-12219-2016, 2016
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We present surface seawater measurements of bromo- and iodocarbons, which are involved in numerous atmospheric processes such as tropospheric and stratospheric ozone chemistry, from the highly productive Peruvian upwelling. By combining trace gas measurements, characterization of organic matter and phytoplankton species, and tropospheric modelling, we show that large amounts of iodocarbons produced from the pool of organic matter may contribute strongly to local tropospheric iodine loading.
Thomas Wagner, Steffen Beirle, Julia Remmers, Reza Shaiganfar, and Yang Wang
Atmos. Meas. Tech., 9, 4803–4823, https://doi.org/10.5194/amt-9-4803-2016, https://doi.org/10.5194/amt-9-4803-2016, 2016
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A method is developed for the calibration of the colour index (CI) and the O4 absorption derived from differential optical absorption spectroscopy (DOAS) measurements of scattered sunlight. Calibrated measurements of the CI and the O4 absorption are important for the detection and classification of clouds from MAX-DOAS observations.
Buhalqem Mamtimin, Franz X. Meixner, Thomas Behrendt, Moawad Badawy, and Thomas Wagner
Atmos. Chem. Phys., 16, 10175–10194, https://doi.org/10.5194/acp-16-10175-2016, https://doi.org/10.5194/acp-16-10175-2016, 2016
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In this study, we focused on the contributions of soil biogenic NO and HONO emissions from a managed hyperarid ecosystem to the regional NOx emissions during growing season. In particular, the second maximum in summer provides substantial evidence to hypothesize that those biogenic emissions from soils of managed drylands in the growing period may be much more important contributors to regional NOx budgets of dryland regions than previously thought.
Erna Frins, Reza Shaiganfar, Ulrich Platt, and Thomas Wagner
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2016-255, https://doi.org/10.5194/amt-2016-255, 2016
Revised manuscript has not been submitted
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Standard methods like in-situ measurements can hardly register NOx (= NO + NO2) emissions from aircrafts during take-off, when engines run at high load and thus an important amount of fuel is consumed and most of the harmful emissions are produced . The goal of this work is to show that it is possible to measure aircraft emissions generated during take-off (and initial part of the climb) by a remote spectroscopic method like automobile – based – Differential Optical Absorption Spectroscopy (DOAS).
Jan Zörner, Marloes Penning de Vries, Steffen Beirle, Holger Sihler, Patrick R. Veres, Jonathan Williams, and Thomas Wagner
Atmos. Chem. Phys., 16, 9457–9487, https://doi.org/10.5194/acp-16-9457-2016, https://doi.org/10.5194/acp-16-9457-2016, 2016
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We present a top-down approach to infer and quantify rain-induced emission pulses of nitrogen oxides from soils using satellite-borne measurements of NO2. We found strong enhancements of NO2 induced by the first intense precipitation after prolonged droughts in many semi-arid regions of the world, in particular in the Sahel. Apart from the clear first-day peak, NO2 VCDs are moderately enhanced compared to background over the following 2 weeks suggesting potential further emissions.
U. Frieß, H. Klein Baltink, S. Beirle, K. Clémer, F. Hendrick, B. Henzing, H. Irie, G. de Leeuw, A. Li, M. M. Moerman, M. van Roozendael, R. Shaiganfar, T. Wagner, Y. Wang, P. Xie, S. Yilmaz, and P. Zieger
Atmos. Meas. Tech., 9, 3205–3222, https://doi.org/10.5194/amt-9-3205-2016, https://doi.org/10.5194/amt-9-3205-2016, 2016
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This article describes the first direct comparison of aerosol extinction profiles from Multi-Axis DOAS measurements of the oxygen collision complex using five different retrieval algorithms. A comparison of the retrieved profiles with co-located aerosol measurements shows good agreement with respect to profile shape and aerosol optical thickness. This study shows that MAX-DOAS is a simple, versatile and cost-effective method for the measurement of aerosol properties in the lower troposphere.
Le Cao, Ulrich Platt, Chenggang Wang, Nianwen Cao, and Qing Qin
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2016-553, https://doi.org/10.5194/acp-2016-553, 2016
Revised manuscript has not been submitted
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A snowpack module which represents the mass transfer between the ambient air and the snowpack is implemented in a box model, aiming to clarify the influences of the snowpack on the ozone depletion events (ODEs) and the associated bromine explosion in the springtime of Arctic. The size of snow grains, volume fraction of the liquid-like layer (LLL), and the rate of the mass exchange between the snow interstitial air and the snow particles are shown to be critical parameters.
Steffen Beirle, Christoph Hörmann, Patrick Jöckel, Song Liu, Marloes Penning de Vries, Andrea Pozzer, Holger Sihler, Pieter Valks, and Thomas Wagner
Atmos. Meas. Tech., 9, 2753–2779, https://doi.org/10.5194/amt-9-2753-2016, https://doi.org/10.5194/amt-9-2753-2016, 2016
Jānis Puķīte and Thomas Wagner
Atmos. Meas. Tech., 9, 2147–2177, https://doi.org/10.5194/amt-9-2147-2016, https://doi.org/10.5194/amt-9-2147-2016, 2016
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We address specialities of differential optical absorption spectroscopy of scattered light in the presence of strong absorbers (like ozone), where the optical depth becomes a non-linear function of the absorber concentration. We quantify the non-linearity using higher-order terms by expanding the radiative transfer equation in a Taylor series.
Fei Liu, Steffen Beirle, Qiang Zhang, Steffen Dörner, Kebin He, and Thomas Wagner
Atmos. Chem. Phys., 16, 5283–5298, https://doi.org/10.5194/acp-16-5283-2016, https://doi.org/10.5194/acp-16-5283-2016, 2016
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We present a new method to quantify NOx emissions and corresponding atmospheric lifetimes from OMI NO2 observations together with ECMWF wind fields without further model input for sources located in polluted background. The derived NOx emissions show generally good agreement with bottom-up inventories for power plants and cities. Global inventory significantly underestimated NOx emissions in Chinese cities, most likely due to uncertainties associated with downscaling approaches.
N. Sobanski, M. J. Tang, J. Thieser, G. Schuster, D. Pöhler, H. Fischer, W. Song, C. Sauvage, J. Williams, J. Fachinger, F. Berkes, P. Hoor, U. Platt, J. Lelieveld, and J. N. Crowley
Atmos. Chem. Phys., 16, 4867–4883, https://doi.org/10.5194/acp-16-4867-2016, https://doi.org/10.5194/acp-16-4867-2016, 2016
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The nitrate radical (NO3) is an important nocturnal oxidant. By measuring NO3, its precursors (nitrogen dioxide and ozone) and several trace gases with which it reacts, we examined the chemical and meteorological factors influencing the lifetime of NO3 at a semi-rural mountain site. Unexpectedly long lifetimes, approaching 1 h, were observed on several nights and were associated with a low-lying residual layer. We discuss the role of other reactions that convert NO2 to NO3.
J. Thieser, G. Schuster, J. Schuladen, G. J. Phillips, A. Reiffs, U. Parchatka, D. Pöhler, J. Lelieveld, and J. N. Crowley
Atmos. Meas. Tech., 9, 553–576, https://doi.org/10.5194/amt-9-553-2016, https://doi.org/10.5194/amt-9-553-2016, 2016
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We report on the use of thermal dissociation cavity ring-down spectroscopy to detect NO2, peroxy nitrates and alkyl nitrates. We present both laboratory studies that characterise the chemical formation and loss of NO2 in the heated inlets and also result from a first field deployment.
Y. Wang, M. Penning de Vries, P. H. Xie, S. Beirle, S. Dörner, J. Remmers, A. Li, and T. Wagner
Atmos. Meas. Tech., 8, 5133–5156, https://doi.org/10.5194/amt-8-5133-2015, https://doi.org/10.5194/amt-8-5133-2015, 2015
J. Lampel, D. Pöhler, J. Tschritter, U. Frieß, and U. Platt
Atmos. Meas. Tech., 8, 4329–4346, https://doi.org/10.5194/amt-8-4329-2015, https://doi.org/10.5194/amt-8-4329-2015, 2015
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In recent updates of the HITRAN water vapour H2O spectroscopic compilation covering the blue spectral region (here 394–-480 nm) significant changes for the absorption bands at 416 and 426 nm were reported. In order to investigate the consistency of the different cross sections calculated from these compilations, H2O vapour column density ratios for different spectral intervals were retrieved from long-path and multi-axis differential optical absorption spectroscopy measurements.
T. Wagner, S. Beirle, S. Dörner, M. Penning de Vries, J. Remmers, A. Rozanov, and R. Shaiganfar
Atmos. Meas. Tech., 8, 4265–4280, https://doi.org/10.5194/amt-8-4265-2015, https://doi.org/10.5194/amt-8-4265-2015, 2015
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We present a new method for the absolute calibration of atmospheric radiance measurements. Existing methods are based on laboratory measurements, but our method uses the atmospheric radiance measurements themselves. For selected sky conditions these measurements are compared to radiative transfer simulations. The method is very accurate (better than 7%) and might be used for a variety of scientific applications, as well as for the determination of the energy yield of photovoltaic cells.
K. D. Custard, C. R. Thompson, K. A. Pratt, P B. Shepson, J. Liao, L. G. Huey, J. J. Orlando, A. J. Weinheimer, E. Apel, S. R. Hall, F. Flocke, L. Mauldin, R. S. Hornbrook, D. Pöhler, S. General, J. Zielcke, W. R. Simpson, U. Platt, A. Fried, P. Weibring, B. C. Sive, K. Ullmann, C. Cantrell, D. J. Knapp, and D. D. Montzka
Atmos. Chem. Phys., 15, 10799–10809, https://doi.org/10.5194/acp-15-10799-2015, https://doi.org/10.5194/acp-15-10799-2015, 2015
M. J. M. Penning de Vries, S. Beirle, C. Hörmann, J. W. Kaiser, P. Stammes, L. G. Tilstra, O. N. E. Tuinder, and T. Wagner
Atmos. Chem. Phys., 15, 10597–10618, https://doi.org/10.5194/acp-15-10597-2015, https://doi.org/10.5194/acp-15-10597-2015, 2015
J. Lampel, U. Frieß, and U. Platt
Atmos. Meas. Tech., 8, 3767–3787, https://doi.org/10.5194/amt-8-3767-2015, https://doi.org/10.5194/amt-8-3767-2015, 2015
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In remote sensing applications, such as differential optical absorption spectroscopy (DOAS), atmospheric scattering processes need to be considered. Inelastic scattering on air molecules can lead to filling-in of absorption lines. The contribution of rotational Raman scattering is typically corrected for. The magnitude of vibrational Raman scattering (VRS) is known from theory and agrees with our first DOAS observations of this effect. Its impact on trace-gas measurements of NO2 is discussed.
R. Shaiganfar, S. Beirle, H. Petetin, Q. Zhang, M. Beekmann, and T. Wagner
Atmos. Meas. Tech., 8, 2827–2852, https://doi.org/10.5194/amt-8-2827-2015, https://doi.org/10.5194/amt-8-2827-2015, 2015
J. Gliß, N. Bobrowski, L. Vogel, D. Pöhler, and U. Platt
Atmos. Chem. Phys., 15, 5659–5681, https://doi.org/10.5194/acp-15-5659-2015, https://doi.org/10.5194/acp-15-5659-2015, 2015
M. Grossi, P. Valks, D. Loyola, B. Aberle, S. Slijkhuis, T. Wagner, S. Beirle, and R. Lang
Atmos. Meas. Tech., 8, 1111–1133, https://doi.org/10.5194/amt-8-1111-2015, https://doi.org/10.5194/amt-8-1111-2015, 2015
P. K. Peterson, W. R. Simpson, K. A. Pratt, P. B. Shepson, U. Frieß, J. Zielcke, U. Platt, S. J. Walsh, and S. V. Nghiem
Atmos. Chem. Phys., 15, 2119–2137, https://doi.org/10.5194/acp-15-2119-2015, https://doi.org/10.5194/acp-15-2119-2015, 2015
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We developed methods to measure the vertical distribution of bromine monoxide, a gas that oxidizes pollutants, above sea ice based upon MAX-DOAS observations from Barrow, Alaska, and find that atmospheric stability exerts a strong control on BrO's vertical distribution. Specifically, more stable (temperature inversion) situations result in BrO being closer to the ground while more neutral (not inverted) atmospheres allow BrO to ascend further aloft and grow to larger column abundance.
B. Mamtimin, T. Behrendt, M. M. Badawy, T. Wagner, Y. Qi, Z. Wu, and F. X. Meixner
Atmos. Chem. Phys., 15, 867–882, https://doi.org/10.5194/acp-15-867-2015, https://doi.org/10.5194/acp-15-867-2015, 2015
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In the paper, very good agreement between measured NO2 (MAX-DOAS) and simulated local ambient NO2 concentrations originating from enhanced soil biogenic NO emission was found. This agreement is considered as the first successful attempt to prove the validity of the chosen approach to upscale laboratory-derived biogenic NO fluxes to ecosystem field conditions. We believe that these topics and key findings make our article suitable for a wider scientific audience and for the interested public.
J. Kuhn, N. Bobrowski, P. Lübcke, L. Vogel, and U. Platt
Atmos. Meas. Tech., 7, 3705–3715, https://doi.org/10.5194/amt-7-3705-2014, https://doi.org/10.5194/amt-7-3705-2014, 2014
S. General, D. Pöhler, H. Sihler, N. Bobrowski, U. Frieß, J. Zielcke, M. Horbanski, P. B. Shepson, B. H. Stirm, W. R. Simpson, K. Weber, C. Fischer, and U. Platt
Atmos. Meas. Tech., 7, 3459–3485, https://doi.org/10.5194/amt-7-3459-2014, https://doi.org/10.5194/amt-7-3459-2014, 2014
S. Beirle, W. Koshak, R. Blakeslee, and T. Wagner
Nat. Hazards Earth Syst. Sci., 14, 2715–2726, https://doi.org/10.5194/nhess-14-2715-2014, https://doi.org/10.5194/nhess-14-2715-2014, 2014
S. Beirle, C. Hörmann, M. Penning de Vries, S. Dörner, C. Kern, and T. Wagner
Atmos. Chem. Phys., 14, 8309–8322, https://doi.org/10.5194/acp-14-8309-2014, https://doi.org/10.5194/acp-14-8309-2014, 2014
M. J. M. Penning de Vries, S. Dörner, J. Puķīte, C. Hörmann, M. D. Fromm, and T. Wagner
Atmos. Chem. Phys., 14, 8149–8163, https://doi.org/10.5194/acp-14-8149-2014, https://doi.org/10.5194/acp-14-8149-2014, 2014
R. Van Malderen, H. Brenot, E. Pottiaux, S. Beirle, C. Hermans, M. De Mazière, T. Wagner, H. De Backer, and C. Bruyninx
Atmos. Meas. Tech., 7, 2487–2512, https://doi.org/10.5194/amt-7-2487-2014, https://doi.org/10.5194/amt-7-2487-2014, 2014
K.-P. Heue, H. Riede, D. Walter, C. A. M. Brenninkmeijer, T. Wagner, U. Frieß, U. Platt, A. Zahn, G. Stratmann, and H. Ziereis
Atmos. Chem. Phys., 14, 6621–6642, https://doi.org/10.5194/acp-14-6621-2014, https://doi.org/10.5194/acp-14-6621-2014, 2014
Y. Wang, A. Li, P. H. Xie, T. Wagner, H. Chen, W. Q. Liu, and J. G. Liu
Atmos. Meas. Tech., 7, 1663–1680, https://doi.org/10.5194/amt-7-1663-2014, https://doi.org/10.5194/amt-7-1663-2014, 2014
P. Lübcke, N. Bobrowski, S. Arellano, B. Galle, G. Garzón, L. Vogel, and U. Platt
Solid Earth, 5, 409–424, https://doi.org/10.5194/se-5-409-2014, https://doi.org/10.5194/se-5-409-2014, 2014
T. Wagner, A. Apituley, S. Beirle, S. Dörner, U. Friess, J. Remmers, and R. Shaiganfar
Atmos. Meas. Tech., 7, 1289–1320, https://doi.org/10.5194/amt-7-1289-2014, https://doi.org/10.5194/amt-7-1289-2014, 2014
S. Bleicher, J. C. Buxmann, R. Sander, T. P. Riedel, J. A. Thornton, U. Platt, and C. Zetzsch
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-14-10135-2014, https://doi.org/10.5194/acpd-14-10135-2014, 2014
Revised manuscript has not been submitted
L. Cao, H. Sihler, U. Platt, and E. Gutheil
Atmos. Chem. Phys., 14, 3771–3787, https://doi.org/10.5194/acp-14-3771-2014, https://doi.org/10.5194/acp-14-3771-2014, 2014
C. Liu, S. Beirle, T. Butler, P. Hoor, C. Frankenberg, P. Jöckel, M. Penning de Vries, U. Platt, A. Pozzer, M. G. Lawrence, J. Lelieveld, H. Tost, and T. Wagner
Atmos. Chem. Phys., 14, 1717–1732, https://doi.org/10.5194/acp-14-1717-2014, https://doi.org/10.5194/acp-14-1717-2014, 2014
D. J. Hoch, J. Buxmann, H. Sihler, D. Pöhler, C. Zetzsch, and U. Platt
Atmos. Meas. Tech., 7, 199–214, https://doi.org/10.5194/amt-7-199-2014, https://doi.org/10.5194/amt-7-199-2014, 2014
J. Yoon, A. Pozzer, P. Hoor, D. Y. Chang, S. Beirle, T. Wagner, S. Schloegl, J. Lelieveld, and H. M. Worden
Atmos. Chem. Phys., 13, 11307–11316, https://doi.org/10.5194/acp-13-11307-2013, https://doi.org/10.5194/acp-13-11307-2013, 2013
R. M. Varma, S. M. Ball, T. Brauers, H.-P. Dorn, U. Heitmann, R. L. Jones, U. Platt, D. Pöhler, A. A. Ruth, A. J. L. Shillings, J. Thieser, A. Wahner, and D. S. Venables
Atmos. Meas. Tech., 6, 3115–3130, https://doi.org/10.5194/amt-6-3115-2013, https://doi.org/10.5194/amt-6-3115-2013, 2013
T. Wagner, S. Beirle, H. Sihler, and K. Mies
Atmos. Meas. Tech., 6, 2593–2605, https://doi.org/10.5194/amt-6-2593-2013, https://doi.org/10.5194/amt-6-2593-2013, 2013
A. Steffen, J. Bottenheim, A. Cole, T. A. Douglas, R. Ebinghaus, U. Friess, S. Netcheva, S. Nghiem, H. Sihler, and R. Staebler
Atmos. Chem. Phys., 13, 7007–7021, https://doi.org/10.5194/acp-13-7007-2013, https://doi.org/10.5194/acp-13-7007-2013, 2013
C. Hörmann, H. Sihler, N. Bobrowski, S. Beirle, M. Penning de Vries, U. Platt, and T. Wagner
Atmos. Chem. Phys., 13, 4749–4781, https://doi.org/10.5194/acp-13-4749-2013, https://doi.org/10.5194/acp-13-4749-2013, 2013
H.-P. Dorn, R. L. Apodaca, S. M. Ball, T. Brauers, S. S. Brown, J. N. Crowley, W. P. Dubé, H. Fuchs, R. Häseler, U. Heitmann, R. L. Jones, A. Kiendler-Scharr, I. Labazan, J. M. Langridge, J. Meinen, T. F. Mentel, U. Platt, D. Pöhler, F. Rohrer, A. A. Ruth, E. Schlosser, G. Schuster, A. J. L. Shillings, W. R. Simpson, J. Thieser, R. Tillmann, R. Varma, D. S. Venables, and A. Wahner
Atmos. Meas. Tech., 6, 1111–1140, https://doi.org/10.5194/amt-6-1111-2013, https://doi.org/10.5194/amt-6-1111-2013, 2013
K. Großmann, U. Frieß, E. Peters, F. Wittrock, J. Lampel, S. Yilmaz, J. Tschritter, R. Sommariva, R. von Glasow, B. Quack, K. Krüger, K. Pfeilsticker, and U. Platt
Atmos. Chem. Phys., 13, 3363–3378, https://doi.org/10.5194/acp-13-3363-2013, https://doi.org/10.5194/acp-13-3363-2013, 2013
P. Lübcke, N. Bobrowski, S. Illing, C. Kern, J. M. Alvarez Nieves, L. Vogel, J. Zielcke, H. Delgado Granados, and U. Platt
Atmos. Meas. Tech., 6, 677–696, https://doi.org/10.5194/amt-6-677-2013, https://doi.org/10.5194/amt-6-677-2013, 2013
S. Beirle, H. Sihler, and T. Wagner
Atmos. Meas. Tech., 6, 661–675, https://doi.org/10.5194/amt-6-661-2013, https://doi.org/10.5194/amt-6-661-2013, 2013
J. Z. Ma, S. Beirle, J. L. Jin, R. Shaiganfar, P. Yan, and T. Wagner
Atmos. Chem. Phys., 13, 1547–1567, https://doi.org/10.5194/acp-13-1547-2013, https://doi.org/10.5194/acp-13-1547-2013, 2013
G. Pinardi, M. Van Roozendael, N. Abuhassan, C. Adams, A. Cede, K. Clémer, C. Fayt, U. Frieß, M. Gil, J. Herman, C. Hermans, F. Hendrick, H. Irie, A. Merlaud, M. Navarro Comas, E. Peters, A. J. M. Piters, O. Puentedura, A. Richter, A. Schönhardt, R. Shaiganfar, E. Spinei, K. Strong, H. Takashima, M. Vrekoussis, T. Wagner, F. Wittrock, and S. Yilmaz
Atmos. Meas. Tech., 6, 167–185, https://doi.org/10.5194/amt-6-167-2013, https://doi.org/10.5194/amt-6-167-2013, 2013
T. Wagner, M. O. Andreae, S. Beirle, S. Dörner, K. Mies, and R. Shaiganfar
Atmos. Meas. Tech., 6, 131–149, https://doi.org/10.5194/amt-6-131-2013, https://doi.org/10.5194/amt-6-131-2013, 2013
Related subject area
Subject: Gases | Research Activity: Remote Sensing | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Development of a high-spatial-resolution annual emission inventory of greenhouse gases from open straw burning in Northeast China from 2001 to 2020
Quantifying large methane emissions from the Nord Stream pipeline gas leak of September 2022 using IASI satellite observations and inverse modelling
Automated detection of regions with persistently enhanced methane concentrations using Sentinel-5 Precursor satellite data
Biomass burning CO emissions: exploring insights through TROPOMI-derived emissions and emission coefficients
Measurement report: Combined use of MAX-DOAS and AERONET ground-based measurements in Montevideo, Uruguay, for the detection of distant biomass burning
Analysis of the long-range transport of the volcanic plume from the 2021 Tajogaite/Cumbre Vieja eruption to Europe using TROPOMI and ground-based measurements
Evaluation of the WRF-Chem Performance for gaseous pollutants over the United Arab Emirates
Quantifying CH4 emissions from coal mine aggregation areas in Shanxi, China, using TROPOMI observations and the wind-assigned anomaly method
SO2 emissions and lifetimes derived from TROPOMI observations over India using a flux-divergence method
Identifying episodic carbon monoxide emission events in the MOPITT measurement dataset
Quantifying effects of long-range transport of NO2 over Delhi using back trajectories and satellite data
Measurement report: Ammonia in Paris derived from ground-based open-path and satellite observations
Anthropogenic CO2 emission estimates in the Tokyo metropolitan area from ground-based CO2 column observations
Characterizing the tropospheric water vapor spatial variation and trend using 2007–2018 COSMIC radio occultation and ECMWF reanalysis data
Detecting nitrogen oxide emissions in Qatar and quantifying emission factors of gas-fired power plants – a 4-year study
Identifying and accounting for the Coriolis effect in satellite NO2 observations and emission estimates
Characterisations of Europe's integrated water vapour and assessments of atmospheric reanalyses using more than 2 decades of ground-based GPS
Ground-level gaseous pollutants (NO2, SO2, and CO) in China: daily seamless mapping and spatiotemporal variations
NH3 spatiotemporal variability over Paris, Mexico City, and Toronto, and its link to PM2.5 during pollution events
Multi-axis differential optical absorption spectroscopy (MAX-DOAS) observations of formaldehyde and nitrogen dioxide at three sites in Asia and comparison with the global chemistry transport model CHASER
Quantifying CH4 emissions in hard coal mines from TROPOMI and IASI observations using the wind-assigned anomaly method
Estimation of surface ammonia concentrations and emissions in China from the polar-orbiting Infrared Atmospheric Sounding Interferometer and the FY-4A Geostationary Interferometric Infrared Sounder
Interannual variability in the Australian carbon cycle over 2015–2019, based on assimilation of Orbiting Carbon Observatory-2 (OCO-2) satellite data
Source and variability of formaldehyde (HCHO) at northern high latitudes: an integrated satellite, aircraft, and model study
Volcanic SO2 layer height by TROPOMI/S5P: evaluation against IASI/MetOp and CALIOP/CALIPSO observations
Spaceborne tropospheric nitrogen dioxide (NO2) observations from 2005–2020 over the Yangtze River Delta (YRD), China: variabilities, implications, and drivers
Novel assessment of numerical forecasting model relative humidity with satellite probabilistic estimates
Influence of springtime atmospheric circulation types on the distribution of air pollutants in the Arctic
Technical note: Evaluation of profile retrievals of aerosols and trace gases for MAX-DOAS measurements under different aerosol scenarios based on radiative transfer simulations
Diurnal evolution of total column and surface atmospheric ammonia in the megacity of Paris, France, during an intense springtime pollution episode
The reduction in C2H6 from 2015 to 2020 over Hefei, eastern China, points to air quality improvement in China
Mapping the drivers of formaldehyde (HCHO) variability from 2015 to 2019 over eastern China: insights from Fourier transform infrared observation and GEOS-Chem model simulation
The impact of Los Angeles Basin pollution and stratospheric intrusions on the surrounding San Gabriel Mountains as seen by surface measurements, lidar, and numerical models
Sudden changes in nitrogen dioxide emissions over Greece due to lockdown after the outbreak of COVID-19
Monitoring CO emissions of the metropolis Mexico City using TROPOMI CO observations
Pollution trace gas distributions and their transport in the Asian monsoon upper troposphere and lowermost stratosphere during the StratoClim campaign 2017
Spatial distribution of enhanced BrO and its relation to meteorological parameters in Arctic and Antarctic sea ice regions
Trends of atmospheric water vapour in Switzerland from ground-based radiometry, FTIR and GNSS data
A Raman lidar tropospheric water vapour climatology and height-resolved trend analysis over Payerne, Switzerland
The potential of Orbiting Carbon Observatory-2 data to reduce the uncertainties in CO2 surface fluxes over Australia using a variational assimilation scheme
Observing carbon dioxide emissions over China's cities and industrial areas with the Orbiting Carbon Observatory-2
Observational evidence of moistening the lowermost stratosphere via isentropic mixing across the subtropical jet
Fourier transform infrared time series of tropospheric HCN in eastern China: seasonality, interannual variability, and source attribution
NH3 emissions from large point sources derived from CrIS and IASI satellite observations
Diurnal cycle of short-term fluctuations of integrated water vapour above Switzerland
Retrieval of total column and surface NO2 from Pandora zenith-sky measurements
MAX-DOAS measurements of tropospheric NO2 and HCHO in Nanjing and a comparison to ozone monitoring instrument observations
Consistency and representativeness of integrated water vapour from ground-based GPS observations and ERA-Interim reanalysis
Towards monitoring localized CO2 emissions from space: co-located regional CO2 and NO2 enhancements observed by the OCO-2 and S5P satellites
Variability of bulk water vapor content in the marine cloudy boundary layers from microwave and near-infrared imagery
Zihan Song, Leiming Zhang, Chongguo Tian, Qiang Fu, Zhenxing Shen, Renjian Zhang, Dong Liu, and Song Cui
Atmos. Chem. Phys., 24, 13101–13113, https://doi.org/10.5194/acp-24-13101-2024, https://doi.org/10.5194/acp-24-13101-2024, 2024
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A novel concept integrating crop cycle information into fire spot extraction was proposed. Spatiotemporal variations of open straw burning in Northeast China are revealed. Open straw burning in Northeast China emitted a total of 218 Tg of CO2-eq during 2001–2020. The policy of banning straw burning effectively reduced greenhouse gas emissions.
Chris Wilson, Brian J. Kerridge, Richard Siddans, David P. Moore, Lucy J. Ventress, Emily Dowd, Wuhu Feng, Martyn P. Chipperfield, and John J. Remedios
Atmos. Chem. Phys., 24, 10639–10653, https://doi.org/10.5194/acp-24-10639-2024, https://doi.org/10.5194/acp-24-10639-2024, 2024
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The leaks from the Nord Stream gas pipelines in September 2022 released a large amount of methane (CH4) into the atmosphere. We provide observational data from a satellite instrument that shows a large CH4 plume over the North Sea off the coast of Scandinavia. We use this together with atmospheric models to quantify the CH4 leaked into the atmosphere from the pipelines. We find that 219–427 Gg CH4 was emitted, making this the largest individual fossil-fuel-related CH4 leak on record.
Steffen Vanselow, Oliver Schneising, Michael Buchwitz, Maximilian Reuter, Heinrich Bovensmann, Hartmut Boesch, and John P. Burrows
Atmos. Chem. Phys., 24, 10441–10473, https://doi.org/10.5194/acp-24-10441-2024, https://doi.org/10.5194/acp-24-10441-2024, 2024
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We developed an algorithm to automatically detect persistent methane source regions, to quantify their emissions and to determine their source types, by analyzing TROPOMI data from 2018–2021. The over 200 globally detected natural and anthropogenic source regions include small-scale point sources such as individual coal mines and larger-scale source regions such as wetlands and large oil and gas fields.
Debora Griffin, Jack Chen, Kerry Anderson, Paul Makar, Chris A. McLinden, Enrico Dammers, and Andre Fogal
Atmos. Chem. Phys., 24, 10159–10186, https://doi.org/10.5194/acp-24-10159-2024, https://doi.org/10.5194/acp-24-10159-2024, 2024
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Satellite-derived CO emissions provide new insights into the understanding of global CO emission rates from wildfires. We use TROPOMI satellite data to create a global inventory database of wildfire CO emissions. These satellite-derived wildfire emissions are used for the evaluation and improvement of existing fire emission inventories and to examine how the wildfire CO emissions have changed over the past 2 decades.
Matías Osorio, Alejandro Agesta, Tim Bösch, Nicolás Casaballe, Andreas Richter, Leonardo M. A. Alvarado, and Erna Frins
Atmos. Chem. Phys., 24, 7447–7465, https://doi.org/10.5194/acp-24-7447-2024, https://doi.org/10.5194/acp-24-7447-2024, 2024
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This study concerns the detection and quantification of long-transport emissions of a biomass burning event, which represents a major source of air pollutants, due to the release of large amounts of aerosols and chemical species into the atmosphere. The quantification was done using ground-based observations (which play an important role in assessing the abundance of trace gases and aerosols) over Montevideo (Uruguay) and using satellite observations.
Pascal Hedelt, Jens Reichardt, Felix Lauermann, Benjamin Weiß, Nicolas Theys, Alberto Redondas, Africa Barreto, Omaira Garcia, and Diego Loyola
EGUsphere, https://doi.org/10.5194/egusphere-2024-1710, https://doi.org/10.5194/egusphere-2024-1710, 2024
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The 2021 volcanic eruption of Tajogaite on La Palma is investigated using ground-based and satellite measurements. In addition, the atmospheric transport of the volcanic cloud towards Europe isstudied in detail. The amount of SO2 released during the eruption as well as the height of the volcanic plume is in excellent agreement between the different measurements. Furthermore, volcanic aerosol microphysical properties could be retrieved using a new retrieval approach based on Lidar measurements.
Yesobu Yarragunta, Diana Francis, Ricardo Fonseca, and Narendra Nelli
EGUsphere, https://doi.org/10.5194/egusphere-2024-959, https://doi.org/10.5194/egusphere-2024-959, 2024
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This study consists of a comprehensive evaluation of the WRF-Chem model for concentrations of gaseous pollutants against satellite observations over the United Arab Emirates. The model showed high skills in simulating the observed concentrations of ozone and NO2, however it has discrepancies in reproducing the observed CO concentrations with an overestimation in summer and underestimation in winter. The model showed high performance in terms of meteorological parameters.
Qiansi Tu, Frank Hase, Kai Qin, Jason Blake Cohen, Farahnaz Khosrawi, Xinrui Zou, Matthias Schneider, and Fan Lu
Atmos. Chem. Phys., 24, 4875–4894, https://doi.org/10.5194/acp-24-4875-2024, https://doi.org/10.5194/acp-24-4875-2024, 2024
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Four-year satellite observations of XCH4 are used to derive CH4 emissions in three regions of China’s coal-rich Shanxi province. The wind-assigned anomalies for two opposite wind directions are calculated, and the estimated emission rates are comparable to the current bottom-up inventory but lower than the CAMS and EDGAR inventories. This research enhances the understanding of emissions in Shanxi and supports climate mitigation strategies by validating emission inventories.
Yutao Chen, Ronald J. van der A, Jieying Ding, Henk Eskes, Jason E. Williams, Nicolas Theys, Athanasios Tsikerdekis, and Pieternel F. Levelt
EGUsphere, https://doi.org/10.5194/egusphere-2024-1094, https://doi.org/10.5194/egusphere-2024-1094, 2024
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There is a lack of local SO2 top-down emission inventories in India. With the improvement in the divergence method and the derivation of SO2 local lifetime, gridded SO2 emissions over a large area can be estimated efficiently. This method can be applied to any region in the world to derive SO2 emissions. Especially for regions with high latitudes, our methodology has the potential to significantly improve the top-down derivation of SO2 emission estimates.
Paul S. Jeffery, James R. Drummond, Jiansheng Zou, and Kaley A. Walker
Atmos. Chem. Phys., 24, 4253–4263, https://doi.org/10.5194/acp-24-4253-2024, https://doi.org/10.5194/acp-24-4253-2024, 2024
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The MOPITT instrument has been monitoring carbon monoxide (CO) since March 2000. This dataset has been used for many applications; however, episodic emission events, which release large amounts of CO into the atmosphere, are a major source of uncertainty. This study presents a method for identifying these events by determining measurements that are unlikely to have typically arisen. The distribution and frequency of these flagged measurements in the MOPITT dataset are presented and discussed.
Ailish M. Graham, Richard J. Pope, Martyn P. Chipperfield, Sandip S. Dhomse, Matilda Pimlott, Wuhu Feng, Vikas Singh, Ying Chen, Oliver Wild, Ranjeet Sokhi, and Gufran Beig
Atmos. Chem. Phys., 24, 789–806, https://doi.org/10.5194/acp-24-789-2024, https://doi.org/10.5194/acp-24-789-2024, 2024
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Our paper uses novel satellite datasets and high-resolution emissions datasets alongside a back-trajectory model to investigate the balance of local and external sources influencing NOx air pollution changes in Delhi. We find in the post-monsoon season that NOx from local and non-local transport emissions contributes most to poor air quality in Delhi. Therefore, air quality mitigation strategies in Delhi and surrounding regions are used to control this issue.
Camille Viatte, Nadir Guendouz, Clarisse Dufaux, Arjan Hensen, Daan Swart, Martin Van Damme, Lieven Clarisse, Pierre Coheur, and Cathy Clerbaux
Atmos. Chem. Phys., 23, 15253–15267, https://doi.org/10.5194/acp-23-15253-2023, https://doi.org/10.5194/acp-23-15253-2023, 2023
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Ammonia (NH3) is an important air pollutant which, as a precursor of fine particulate matter, raises public health concerns. Models have difficulty predicting events of pollution associated with NH3 since ground-based observations of this gas are still relatively sparse and difficult to implement. We present the first relatively long (2.5 years) and continuous record of hourly NH3 concentrations in Paris to determine its temporal variabilities at different scales to unravel emission sources.
Hirofumi Ohyama, Matthias M. Frey, Isamu Morino, Kei Shiomi, Masahide Nishihashi, Tatsuya Miyauchi, Hiroko Yamada, Makoto Saito, Masanobu Wakasa, Thomas Blumenstock, and Frank Hase
Atmos. Chem. Phys., 23, 15097–15119, https://doi.org/10.5194/acp-23-15097-2023, https://doi.org/10.5194/acp-23-15097-2023, 2023
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We conducted a field campaign for CO2 column measurements in the Tokyo metropolitan area with three ground-based Fourier transform spectrometers. The model simulations using prior CO2 fluxes were generally in good agreement with the observations. We developed an urban-scale inversion system in which spatially resolved CO2 fluxes and a scaling factor of large point source emissions were estimated. The posterior total CO2 emissions agreed with emission inventories within the posterior uncertainty.
Xi Shao, Shu-Peng Ho, Xin Jing, Xinjia Zhou, Yong Chen, Tung-Chang Liu, Bin Zhang, and Jun Dong
Atmos. Chem. Phys., 23, 14187–14218, https://doi.org/10.5194/acp-23-14187-2023, https://doi.org/10.5194/acp-23-14187-2023, 2023
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Atmospheric water vapor plays an essential role in the global energy balance, hydrological cycle, and climate system. This paper characterizes and compares the global, latitudinal, and regional variabilities of COSMIC and ERA5 water vapor distribution, as well as the seasonality and long-term trends at selected pressure levels from 2007 to 2018. Evaluation of spatiotemporal variabilities of atmospheric water vapor ensures the qualities of COSMIC and reanalysis water vapor for climate studies.
Anthony Rey-Pommier, Frédéric Chevallier, Philippe Ciais, Jonilda Kushta, Theodoros Christoudias, I. Safak Bayram, and Jean Sciare
Atmos. Chem. Phys., 23, 13565–13583, https://doi.org/10.5194/acp-23-13565-2023, https://doi.org/10.5194/acp-23-13565-2023, 2023
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We use four years (2019–2022) of TROPOMI NO2 data to map NOx emissions in Qatar. We estimate average monthly emissions for the country and industrial facilities and derive an emission factor for the power sector. Monthly emissions have a weekly cycle reflecting the social norms in Qatar and an annual cycle consistent with the electricity production by gas-fired power plants. Their mean value is lower than the NOx emissions in global inventories but similar to the emissions reported for 2007.
Daniel A. Potts, Roger Timmis, Emma J. S. Ferranti, and Joshua D. Vande Hey
Atmos. Chem. Phys., 23, 4577–4593, https://doi.org/10.5194/acp-23-4577-2023, https://doi.org/10.5194/acp-23-4577-2023, 2023
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With the launch of the TROPOspheric Monitoring Instrument (TROPOMI) in 2017, it is now possible to observe pollutants emitted from individual industrial facilities on a daily basis around the globe. By using observations of nitrogen dioxide (NO2) from 16 different industrial sites, we show how the Coriolis effect influences the trajectory of these emission plumes as well as how the additional curvature can lead to a substantial underestimation of the calculated emissions.
Peng Yuan, Roeland Van Malderen, Xungang Yin, Hannes Vogelmann, Weiping Jiang, Joseph Awange, Bernhard Heck, and Hansjörg Kutterer
Atmos. Chem. Phys., 23, 3517–3541, https://doi.org/10.5194/acp-23-3517-2023, https://doi.org/10.5194/acp-23-3517-2023, 2023
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Water vapour plays an important role in various weather and climate processes. However, due to its large spatiotemporal variability, its high-accuracy quantification remains a challenge. In this study, 20+ years of GPS-derived integrated water vapour (IWV) retrievals in Europe were obtained. They were then used to characterise the temporal features of Europe's IWV and assess six atmospheric reanalyses. Results show that ERA5 outperforms the other reanalyses at most temporal scales.
Jing Wei, Zhanqing Li, Jun Wang, Can Li, Pawan Gupta, and Maureen Cribb
Atmos. Chem. Phys., 23, 1511–1532, https://doi.org/10.5194/acp-23-1511-2023, https://doi.org/10.5194/acp-23-1511-2023, 2023
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This study estimated the daily seamless 10 km ambient gaseous pollutants (NO2, SO2, and CO) across China using machine learning with extensive input variables measured on monitors, satellites, and models. Our dataset yields a high data quality via cross-validation at varying spatiotemporal scales and outperforms most previous related studies, making it most helpful to future (especially short-term) air pollution and environmental health-related studies.
Camille Viatte, Rimal Abeed, Shoma Yamanouchi, William C. Porter, Sarah Safieddine, Martin Van Damme, Lieven Clarisse, Beatriz Herrera, Michel Grutter, Pierre-Francois Coheur, Kimberly Strong, and Cathy Clerbaux
Atmos. Chem. Phys., 22, 12907–12922, https://doi.org/10.5194/acp-22-12907-2022, https://doi.org/10.5194/acp-22-12907-2022, 2022
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Large cities can experience high levels of fine particulate matter (PM2.5) pollution linked to ammonia (NH3) mainly emitted from agricultural activities. Using a combination of PM2.5 and NH3 measurements from in situ instruments, satellite infrared spectrometers, and atmospheric model simulations, we have demonstrated the role of NH3 and meteorological conditions on pollution events occurring over Paris, Toronto, and Mexico City.
Hossain Mohammed Syedul Hoque, Kengo Sudo, Hitoshi Irie, Alessandro Damiani, Manish Naja, and Al Mashroor Fatmi
Atmos. Chem. Phys., 22, 12559–12589, https://doi.org/10.5194/acp-22-12559-2022, https://doi.org/10.5194/acp-22-12559-2022, 2022
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Nitrogen dioxide (NO2) and formaldehyde (HCHO) are essential trace graces regulating tropospheric ozone chemistry. These trace constituents are measured using an optical passive remote sensing technique. In addition, NO2 and HCHO are simulated with a computer model and evaluated against the observations. Such evaluations are essential to assess model uncertainties and improve their predictability. The results yielded good agreement between the two datasets with some discrepancies.
Qiansi Tu, Matthias Schneider, Frank Hase, Farahnaz Khosrawi, Benjamin Ertl, Jaroslaw Necki, Darko Dubravica, Christopher J. Diekmann, Thomas Blumenstock, and Dianjun Fang
Atmos. Chem. Phys., 22, 9747–9765, https://doi.org/10.5194/acp-22-9747-2022, https://doi.org/10.5194/acp-22-9747-2022, 2022
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Three-year satellite observations and high-resolution model forecast of XCH4 are used to derive CH4 emissions in the USCB region, Poland – a region of intense coal mining activities. The wind-assigned anomalies for two opposite wind directions are calculated and the estimated emission rates are very close to the inventories and in reasonable agreement with the previous studies. Our method is quite robust and can serve as a simple method to estimate CH4 or CO2 emissions for other regions.
Pu Liu, Jia Ding, Lei Liu, Wen Xu, and Xuejun Liu
Atmos. Chem. Phys., 22, 9099–9110, https://doi.org/10.5194/acp-22-9099-2022, https://doi.org/10.5194/acp-22-9099-2022, 2022
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Ammonia (NH3) is the important alkaline gas and the key component of fine particulate matter. We used satellite-based observations to analyze the changes in hourly NH3 concentrations and estimated surface NH3 concentrations and NH3 emissions in China. This study shows enormous potential for using satellite data to estimate surface NH3 concentrations and NH3 emissions and provides an important reference for understanding NH3 variation in China.
Yohanna Villalobos, Peter J. Rayner, Jeremy D. Silver, Steven Thomas, Vanessa Haverd, Jürgen Knauer, Zoë M. Loh, Nicholas M. Deutscher, David W. T. Griffith, and David F. Pollard
Atmos. Chem. Phys., 22, 8897–8934, https://doi.org/10.5194/acp-22-8897-2022, https://doi.org/10.5194/acp-22-8897-2022, 2022
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We study the interannual variability in Australian carbon fluxes for 2015–2019 derived from OCO-2 satellite data. Our results suggest that Australia's semi-arid ecosystems are highly responsive to variations in climate drivers such as rainfall and temperature. We found that high rainfall and low temperatures recorded in 2016 led to an anomalous carbon sink over savanna and sparsely vegetated regions, while unprecedented dry and hot weather in 2019 led to anomalous carbon release.
Tianlang Zhao, Jingqiu Mao, William R. Simpson, Isabelle De Smedt, Lei Zhu, Thomas F. Hanisco, Glenn M. Wolfe, Jason M. St. Clair, Gonzalo González Abad, Caroline R. Nowlan, Barbara Barletta, Simone Meinardi, Donald R. Blake, Eric C. Apel, and Rebecca S. Hornbrook
Atmos. Chem. Phys., 22, 7163–7178, https://doi.org/10.5194/acp-22-7163-2022, https://doi.org/10.5194/acp-22-7163-2022, 2022
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Monitoring formaldehyde (HCHO) can help us understand Arctic vegetation change. Here, we compare satellite data and model and show that Alaska summertime HCHO is largely dominated by a background from methane oxidation during mild wildfire years and is dominated by wildfire (largely from direct emission of fire) during strong fire years. Consequently, it is challenging to use satellite HCHO to study vegetation change in the Arctic region.
Maria-Elissavet Koukouli, Konstantinos Michailidis, Pascal Hedelt, Isabelle A. Taylor, Antje Inness, Lieven Clarisse, Dimitris Balis, Dmitry Efremenko, Diego Loyola, Roy G. Grainger, and Christian Retscher
Atmos. Chem. Phys., 22, 5665–5683, https://doi.org/10.5194/acp-22-5665-2022, https://doi.org/10.5194/acp-22-5665-2022, 2022
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Volcanic eruptions eject large amounts of ash and trace gases into the atmosphere. The use of space-borne instruments enables the global monitoring of volcanic SO2 emissions in an economical and risk-free manner. The main aim of this paper is to present its extensive verification, accomplished within the ESA S5P+I: SO2LH project, over major recent volcanic eruptions, against collocated space-borne measurements, as well as assess its impact on the forecasts provided by CAMS.
Hao Yin, Youwen Sun, Justus Notholt, Mathias Palm, and Cheng Liu
Atmos. Chem. Phys., 22, 4167–4185, https://doi.org/10.5194/acp-22-4167-2022, https://doi.org/10.5194/acp-22-4167-2022, 2022
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In this study, we quantity the long-term variabilities and the underlying drivers of NO2 from 2005 to 2020 over the Yangtze River Delta (YRD), one of the most densely populated and highly industrialized city clusters in China. We reveal the significant effect of the Action Plan on the Prevention and Control of Air Pollution since 2013 adopted by the Chinese government to reduce NOx pollution. Our study can improve the understanding of pollution control measures on a regional scale.
Chloé Radice, Hélène Brogniez, Pierre-Emmanuel Kirstetter, and Philippe Chambon
Atmos. Chem. Phys., 22, 3811–3825, https://doi.org/10.5194/acp-22-3811-2022, https://doi.org/10.5194/acp-22-3811-2022, 2022
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A novel probabilistic approach is proposed to evaluate relative humidity (RH) profiles simulated by an atmospheric model with respect to satellite-based RH defined from probability distributions. It improves upon deterministic comparisons by enhancing the information content to enable a finer assessment of each model–observation discrepancy, highlighting significant departures within a deterministic confidence range. Geographical and vertical distributions of the model biases are discussed.
Manu Anna Thomas, Abhay Devasthale, and Tiina Nygård
Atmos. Chem. Phys., 21, 16593–16608, https://doi.org/10.5194/acp-21-16593-2021, https://doi.org/10.5194/acp-21-16593-2021, 2021
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The impact of transported pollutants and their spatial distribution in the Arctic are governed by the local atmospheric circulation or weather states. Therefore, we investigated eight different atmospheric circulation types observed during the spring season in the Arctic. Using satellite and reanalysis datasets, this study provides a comprehensive assessment of the typical circulation patterns that can lead to enhanced or reduced pollution concentrations in the different sectors of the Arctic.
Xin Tian, Yang Wang, Steffen Beirle, Pinhua Xie, Thomas Wagner, Jin Xu, Ang Li, Steffen Dörner, Bo Ren, and Xiaomei Li
Atmos. Chem. Phys., 21, 12867–12894, https://doi.org/10.5194/acp-21-12867-2021, https://doi.org/10.5194/acp-21-12867-2021, 2021
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The performances of two MAX-DOAS inversion algorithms were evaluated for various aerosol pollution scenarios. One inversion algorithm is based on optimal estimation; the other uses a parameterized approach. In this analysis, three types of profile shapes for aerosols and NO2 were considered: exponential, Boltzmann, and Gaussian. The evaluation results can effectively guide the application of the two inversion algorithms in the actual atmosphere and improve the accuracy of the actual inversion.
Rebecca D. Kutzner, Juan Cuesta, Pascale Chelin, Jean-Eudes Petit, Mokhtar Ray, Xavier Landsheere, Benoît Tournadre, Jean-Charles Dupont, Amandine Rosso, Frank Hase, Johannes Orphal, and Matthias Beekmann
Atmos. Chem. Phys., 21, 12091–12111, https://doi.org/10.5194/acp-21-12091-2021, https://doi.org/10.5194/acp-21-12091-2021, 2021
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Our work investigates the diurnal evolution of atmospheric ammonia concentrations during a major pollution event. It analyses it in regard of both chemical (gas–particle conversion) and physical (vertical mixing, meteorology) processes in the atmosphere. These mechanisms are key for understanding the evolution of the physicochemical state of the atmosphere; therefore, it clearly fits into the scope of Atmospheric Chemistry and Physics.
Youwen Sun, Hao Yin, Cheng Liu, Emmanuel Mahieu, Justus Notholt, Yao Té, Xiao Lu, Mathias Palm, Wei Wang, Changgong Shan, Qihou Hu, Min Qin, Yuan Tian, and Bo Zheng
Atmos. Chem. Phys., 21, 11759–11779, https://doi.org/10.5194/acp-21-11759-2021, https://doi.org/10.5194/acp-21-11759-2021, 2021
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The variability, sources, and transport of ethane (C2H6) over eastern China from 2015 to 2020 were studied using ground-based Fourier transform infrared (FTIR) spectroscopy and GEOS-Chem simulations. C2H6 variability is driven by both meteorological and emission factors. The reduction in C2H6 in recent years over eastern China points to air quality improvement in China.
Youwen Sun, Hao Yin, Cheng Liu, Lin Zhang, Yuan Cheng, Mathias Palm, Justus Notholt, Xiao Lu, Corinne Vigouroux, Bo Zheng, Wei Wang, Nicholas Jones, Changong Shan, Min Qin, Yuan Tian, Qihou Hu, Fanhao Meng, and Jianguo Liu
Atmos. Chem. Phys., 21, 6365–6387, https://doi.org/10.5194/acp-21-6365-2021, https://doi.org/10.5194/acp-21-6365-2021, 2021
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This study mapped the drivers of HCHO variability from 2015 to 2019 over eastern China. Hydroxyl (OH) radical production rates from HCHO photolysis were evaluated. The relative contributions of emitted and photochemical sources to the observed HCHO abundance were analyzed. Contributions of various emission sources and geographical regions to the observed HCHO summertime enhancements were determined.
Fernando Chouza, Thierry Leblanc, Mark Brewer, Patrick Wang, Sabino Piazzolla, Gabriele Pfister, Rajesh Kumar, Carl Drews, Simone Tilmes, Louisa Emmons, and Matthew Johnson
Atmos. Chem. Phys., 21, 6129–6153, https://doi.org/10.5194/acp-21-6129-2021, https://doi.org/10.5194/acp-21-6129-2021, 2021
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The tropospheric ozone lidar at the JPL Table Mountain Facility (TMF) was used to investigate the impact of Los Angeles (LA) Basin pollution transport and stratospheric intrusions in the planetary boundary layer on the San Gabriel Mountains. The results of this study indicate a dominant role of the LA Basin pollution on days when high ozone levels were observed at TMF (March–October period).
Maria-Elissavet Koukouli, Ioanna Skoulidou, Andreas Karavias, Isaak Parcharidis, Dimitris Balis, Astrid Manders, Arjo Segers, Henk Eskes, and Jos van Geffen
Atmos. Chem. Phys., 21, 1759–1774, https://doi.org/10.5194/acp-21-1759-2021, https://doi.org/10.5194/acp-21-1759-2021, 2021
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In recent years, satellite observations have contributed to monitoring air quality. During the first COVID-19 lockdown, lower levels of nitrogen dioxide were observed over Greece by S5P/TROPOMI for March and April 2020 (than the preceding year) due to decreased transport emissions. Taking meteorology into account, using LOTOS-EUROS CTM simulations, the resulting decline due to the lockdown was estimated to range between 0 % and −37 % for the five largest Greek cities, with an average of ~ −10 %.
Tobias Borsdorff, Agustín García Reynoso, Gilberto Maldonado, Bertha Mar-Morales, Wolfgang Stremme, Michel Grutter, and Jochen Landgraf
Atmos. Chem. Phys., 20, 15761–15774, https://doi.org/10.5194/acp-20-15761-2020, https://doi.org/10.5194/acp-20-15761-2020, 2020
Sören Johansson, Michael Höpfner, Oliver Kirner, Ingo Wohltmann, Silvia Bucci, Bernard Legras, Felix Friedl-Vallon, Norbert Glatthor, Erik Kretschmer, Jörn Ungermann, and Gerald Wetzel
Atmos. Chem. Phys., 20, 14695–14715, https://doi.org/10.5194/acp-20-14695-2020, https://doi.org/10.5194/acp-20-14695-2020, 2020
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We present high-resolution measurements of pollutant trace gases (PAN, C2H2, and HCOOH) in the Asian monsoon UTLS from the airborne limb imager GLORIA during StratoClim 2017. Enhancements are observed up to 16 km altitude, and PAN and C2H2 even up to 18 km. Two atmospheric models, CAMS and EMAC, reproduce the pollutant's large-scale structures but not finer structures. Convection is investigated using backward trajectories of the models ATLAS and TRACZILLA with advanced detection of convection.
Sora Seo, Andreas Richter, Anne-Marlene Blechschmidt, Ilias Bougoudis, and John Philip Burrows
Atmos. Chem. Phys., 20, 12285–12312, https://doi.org/10.5194/acp-20-12285-2020, https://doi.org/10.5194/acp-20-12285-2020, 2020
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In this study, we present spatial distributions of occurrence frequency of enhanced total BrO column and various meteorological parameters affecting it in the Arctic and Antarctic sea ice regions by using 10 years of GOME-2 measurements and meteorological model data. Statistical analysis using the long-term dataset shows clear differences in the meteorological conditions between the mean field and the situation of enhanced total BrO columns in both polar sea ice regions.
Leonie Bernet, Elmar Brockmann, Thomas von Clarmann, Niklaus Kämpfer, Emmanuel Mahieu, Christian Mätzler, Gunter Stober, and Klemens Hocke
Atmos. Chem. Phys., 20, 11223–11244, https://doi.org/10.5194/acp-20-11223-2020, https://doi.org/10.5194/acp-20-11223-2020, 2020
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With global warming, water vapour increases in the atmosphere. Water vapour is an important gas because it is a natural greenhouse gas and affects the formation of clouds, rain and snow. How much water vapour increases can vary in different regions of the world. To verify if it increases as expected on a regional scale, we analysed water vapour measurements in Switzerland. We found that water vapour generally increases as expected from temperature changes, except in winter.
Shannon Hicks-Jalali, Robert J. Sica, Giovanni Martucci, Eliane Maillard Barras, Jordan Voirin, and Alexander Haefele
Atmos. Chem. Phys., 20, 9619–9640, https://doi.org/10.5194/acp-20-9619-2020, https://doi.org/10.5194/acp-20-9619-2020, 2020
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We have calculated an 11.5-year water vapour climatology using the Raman Lidar for Meteorological Observations (RALMO), located in Payerne, Switzerland. The climatology shows that the highest water vapour concentrations are in the summer months and the lowest in the winter months. We present for the first time height-resolved water vapour trends, which show that water vapour increases specific humidity by between 5 % and 15 % per decade depending on the altitude.
Yohanna Villalobos, Peter Rayner, Steven Thomas, and Jeremy Silver
Atmos. Chem. Phys., 20, 8473–8500, https://doi.org/10.5194/acp-20-8473-2020, https://doi.org/10.5194/acp-20-8473-2020, 2020
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Estimated carbon fluxes for Australia are subject to considerable uncertainty. We ran simulation experiments over Australia to determine how much these uncertainties can be constrained using satellite data. We found that the satellite data has the potential to reduce these uncertainties up to 80 % across the whole continent. For 1 month, this percentage corresponds to 0.51 Pg C y-1 for Australia. This method could lead to significantly more accurate estimates of Australia's carbon budget.
Bo Zheng, Frédéric Chevallier, Philippe Ciais, Grégoire Broquet, Yilong Wang, Jinghui Lian, and Yuanhong Zhao
Atmos. Chem. Phys., 20, 8501–8510, https://doi.org/10.5194/acp-20-8501-2020, https://doi.org/10.5194/acp-20-8501-2020, 2020
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The Paris Climate Agreement requires all parties to report CO2 emissions regularly. Given the self-reporting nature of this system, it is critical to evaluate the emission reports with independent observation systems. Here we present the direct observations of city CO2 plumes from space and the quantification of CO2 emissions from these observations over the largest emitter country China. The emissions from 46 hot-spot regions representing 13 % of China's total emissions can be well constrained.
Jeffery Langille, Adam Bourassa, Laura L. Pan, Daniel Letros, Brian Solheim, Daniel Zawada, and Doug Degenstein
Atmos. Chem. Phys., 20, 5477–5486, https://doi.org/10.5194/acp-20-5477-2020, https://doi.org/10.5194/acp-20-5477-2020, 2020
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Water vapour (WV) is a highly variable and extremely important trace gas in Earth’s atmosphere. Due to its radiative and chemical properties, it is coupled to the climate in an extremely complex manner. This is especially true in the lowermost stratosphere (LMS). Despite its importance, the physical processes that control mixing and the distribution of WV in the LMS are poorly understood. This study provides observational evidence of moistening the LMS via mixing across the subtropical jet.
Youwen Sun, Cheng Liu, Lin Zhang, Mathias Palm, Justus Notholt, Hao Yin, Corinne Vigouroux, Erik Lutsch, Wei Wang, Changong Shan, Thomas Blumenstock, Tomoo Nagahama, Isamu Morino, Emmanuel Mahieu, Kimberly Strong, Bavo Langerock, Martine De Mazière, Qihou Hu, Huifang Zhang, Christof Petri, and Jianguo Liu
Atmos. Chem. Phys., 20, 5437–5456, https://doi.org/10.5194/acp-20-5437-2020, https://doi.org/10.5194/acp-20-5437-2020, 2020
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We present multiyear time series of ground-based Fourier-transform infrared spectroscopy measurements of HCN in densely populated eastern China. The seasonality and interannual variability of tropospheric HCN columns were investigated. The potential sources that drive the observed HCN seasonality and interannual variability were determined using a GEOS-Chem tagged CO simulation, global fire maps, and potential source contribution function values calculated using HYSPLIT back trajectories.
Enrico Dammers, Chris A. McLinden, Debora Griffin, Mark W. Shephard, Shelley Van Der Graaf, Erik Lutsch, Martijn Schaap, Yonatan Gainairu-Matz, Vitali Fioletov, Martin Van Damme, Simon Whitburn, Lieven Clarisse, Karen Cady-Pereira, Cathy Clerbaux, Pierre Francois Coheur, and Jan Willem Erisman
Atmos. Chem. Phys., 19, 12261–12293, https://doi.org/10.5194/acp-19-12261-2019, https://doi.org/10.5194/acp-19-12261-2019, 2019
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Ammonia is an essential molecule in the environment, but at its current levels it is unsustainable. However, the emissions are highly uncertain. We explore the use of satellites to estimate the ammonia lifetime and emissions around point sources to help improve the budget. The same method applied to different satellite instruments shows consistent results. Comparison to the emission inventories shows that those are underestimating emissions of point sources by on average a factor of 2.5.
Klemens Hocke, Leonie Bernet, Jonas Hagen, Axel Murk, Matthias Renker, and Christian Mätzler
Atmos. Chem. Phys., 19, 12083–12090, https://doi.org/10.5194/acp-19-12083-2019, https://doi.org/10.5194/acp-19-12083-2019, 2019
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The Tropospheric Water Radiometer (TROWARA) observed an enhanced intensity of short-term integrated water vapour (IWV) fluctuations during daytime in summer. These IWV fluctuations are possibly related to latent heat flux and thermal convective activity in the lower troposphere. The observed climatology and spectra of IWV fluctuations might be useful for modelling studies of water vapour convection in the atmospheric boundary layer at mid latitudes.
Xiaoyi Zhao, Debora Griffin, Vitali Fioletov, Chris McLinden, Jonathan Davies, Akira Ogyu, Sum Chi Lee, Alexandru Lupu, Michael D. Moran, Alexander Cede, Martin Tiefengraber, and Moritz Müller
Atmos. Chem. Phys., 19, 10619–10642, https://doi.org/10.5194/acp-19-10619-2019, https://doi.org/10.5194/acp-19-10619-2019, 2019
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New nitrogen dioxide (NO2) retrieval algorithms are developed for Pandora zenith-sky measurements. A column-to-surface conversion look-up table was produced for the Pandora instruments; therefore, quick and practical Pandora-based surface NO2 concentration data can be obtained for air quality monitoring purposes. It is demonstrated that the surface NO2 concentration is controlled not only by the planetary boundary layer height but also by both boundary layer dynamics and photochemistry.
Ka Lok Chan, Zhuoru Wang, Aijun Ding, Klaus-Peter Heue, Yicheng Shen, Jing Wang, Feng Zhang, Yining Shi, Nan Hao, and Mark Wenig
Atmos. Chem. Phys., 19, 10051–10071, https://doi.org/10.5194/acp-19-10051-2019, https://doi.org/10.5194/acp-19-10051-2019, 2019
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The paper presents long-term observations of atmospheric nitrogen dioxide (NO2) and formaldehyde (HCHO) in Nanjing using a MAX-DOAS instrument. The measurements were performed from April 2013 to February 2017. The MAX-DOAS measurements of NO2 and HCHO are used to validate OMI satellite observations and to investigate the influences of region transport of air pollutants on the air quality in Nanjing.
Olivier Bock and Ana C. Parracho
Atmos. Chem. Phys., 19, 9453–9468, https://doi.org/10.5194/acp-19-9453-2019, https://doi.org/10.5194/acp-19-9453-2019, 2019
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We examine the consistency of global IWV data from ERA-Interim reanalysis and 16 years of GPS observations. Representativeness differences are found to be a dominant error source, with a strong dependence on geographic, topographic, and climatic features, which explain both average and extreme differences. A methodology for reducing the representativeness errors and detecting the extreme, outlying, cases is discussed.
Maximilian Reuter, Michael Buchwitz, Oliver Schneising, Sven Krautwurst, Christopher W. O'Dell, Andreas Richter, Heinrich Bovensmann, and John P. Burrows
Atmos. Chem. Phys., 19, 9371–9383, https://doi.org/10.5194/acp-19-9371-2019, https://doi.org/10.5194/acp-19-9371-2019, 2019
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The quantification of anthropogenic emissions with current CO2 satellite sensors is difficult, but NO2 is co-emitted, making it a suitable tracer of recently emitted CO2. We analyze enhancements of CO2 and NO2 observed by OCO-2 and S5P and estimate the CO2 plume cross-sectional fluxes that we compare with emission databases. Our results demonstrate the usefulness of simultaneous satellite observations of CO2 and NO2 as envisaged for the European Copernicus anthropogenic CO2 monitoring mission
Luis F. Millán, Matthew D. Lebsock, and Joao Teixeira
Atmos. Chem. Phys., 19, 8491–8502, https://doi.org/10.5194/acp-19-8491-2019, https://doi.org/10.5194/acp-19-8491-2019, 2019
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The synergy of the collocated Advanced Microwave Scanning Radiometer (AMSR) and the Moderate Resolution Imaging Spectroradiometer (MODIS) provides daily global estimates of marine boundary layer water vapor. AMSR provides the total column water vapor, while MODIS provides the water vapor above the cloud layers. The difference between the two gives the vapor between the surface and the cloud top, which may be interpreted as the boundary layer water vapor.
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Short summary
Previous publications on the absorptions of the oxygen dimer O2–O2 (or short: O4) list absorption peaks at 328 nm and 419 nm, for which no spectrally resolved literature cross sections are available. As these absorptions potentially influence the spectral retrieval of various other trace gases, their shape and magnitude need to be quantified. We approximate the absorption peaks at 328 nm and 419 nm by their respective neighboring absorption peaks to estimate their magnitude and peak wavelength.
Previous publications on the absorptions of the oxygen dimer O2–O2 (or short: O4) list...
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