Articles | Volume 8, issue 12
Atmos. Meas. Tech., 8, 5039–5062, 2015
https://doi.org/10.5194/amt-8-5039-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Special issue: GOME-2: calibration, algorithms, data products and...
Atmos. Meas. Tech., 8, 5039–5062, 2015
https://doi.org/10.5194/amt-8-5039-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article 02 Dec 2015
Research article | 02 Dec 2015
Metrology of ground-based satellite validation: co-location mismatch and smoothing issues of total ozone comparisons
T. Verhoelst et al.
Related authors
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.
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).
Daan Hubert, Klaus-Peter Heue, Jean-Christopher Lambert, Tijl Verhoelst, Marc Allaart, Steven Compernolle, Patrick D. Cullis, Angelika Dehn, Christian Félix, Bryan J. Johnson, Arno Keppens, Debra E. Kollonige, Christophe Lerot, Diego Loyola, Matakite Maata, Sukarni Mitro, Maznorizan Mohamad, Ankie Piters, Fabian Romahn, Henry B. Selkirk, Francisco R. da Silva, Ryan M. Stauffer, Anne M. Thompson, J. Pepijn Veefkind, Holger Vömel, Jacquelyn C. Witte, and Claus Zehner
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-123, https://doi.org/10.5194/amt-2020-123, 2020
Revised manuscript has not been submitted
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We assess the first two years of TROPOMI tropical tropospheric ozone column data. Comparisons to reference measurements by ozonesonde and satellite sensors show that TROPOMI bias (−0.1 to +2.3 DU) and precision (1.5 to 2.5 DU) meet mission requirements. Potential causes of bias and its spatio-temporal structure are discussed, as well as ways to identify sampling errors. The analysis of the known geophysical patterns demonstrates the improved performance of TROPOMI with respect to predecessors.
Steven Compernolle, Athina Argyrouli, Ronny Lutz, Maarten Sneep, Jean-Christopher Lambert, Ann Mari Fjæraa, Daan Hubert, Arno Keppens, Diego Loyola, Ewan O'Connor, Fabian Romahn, Piet Stammes, Tijl Verhoelst, and Ping Wang
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-122, https://doi.org/10.5194/amt-2020-122, 2020
Revised manuscript accepted for AMT
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The high-resolution satellite Sentinel-5p TROPOMI observes several atmospheric gases. To account for cloud interference with the observations, S5P cloud data products (CLOUD OCRA/ROCINN_CAL, OCRA/ROCINN_CRB and FRESCO) provide vital input: cloud fraction, cloud height and cloud optical thickness.
Here, the S5P cloud parameters are validated by comparing with other satellite sensors (VIIRS, MODIS, OMI) and with ground-based CLOUDNET data. The agreement depends on product type and cloud height.
Katerina Garane, Maria-Elissavet Koukouli, Tijl Verhoelst, Christophe Lerot, Klaus-Peter Heue, Vitali Fioletov, Dimitrios Balis, Alkiviadis Bais, Ariane Bazureau, Angelika Dehn, Florence Goutail, Jose Granville, Debora Griffin, Daan Hubert, Arno Keppens, Jean-Christopher Lambert, Diego Loyola, Chris McLinden, Andrea Pazmino, Jean-Pierre Pommereau, Alberto Redondas, Fabian Romahn, Pieter Valks, Michel Van Roozendael, Jian Xu, Claus Zehner, Christos Zerefos, and Walter Zimmer
Atmos. Meas. Tech., 12, 5263–5287, https://doi.org/10.5194/amt-12-5263-2019, https://doi.org/10.5194/amt-12-5263-2019, 2019
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The Sentinel-5 Precursor TROPOMI near real time (NRTI) and offline (OFFL) total ozone column (TOC) products are validated against direct-sun and twilight zenith-sky ground-based TOC measurements and other already known spaceborne sensors. The results show that the TROPOMI TOC measurements are in very good agreement with the ground-based measurements and satellite sensor measurements and that they are well within the product requirements.
Arno Keppens, Jean-Christopher Lambert, José Granville, Daan Hubert, Tijl Verhoelst, Steven Compernolle, Barry Latter, Brian Kerridge, Richard Siddans, Anne Boynard, Juliette Hadji-Lazaro, Cathy Clerbaux, Catherine Wespes, Daniel R. Hurtmans, Pierre-François Coheur, Jacob C. A. van Peet, Ronald J van der A, Katerina Garane, Maria Elissavet Koukouli, Dimitris S. Balis, Andy Delcloo, Rigel Kivi, Réné Stübi, Sophie Godin-Beekmann, Michel Van Roozendael, and Claus Zehner
Atmos. Meas. Tech., 11, 3769–3800, https://doi.org/10.5194/amt-11-3769-2018, https://doi.org/10.5194/amt-11-3769-2018, 2018
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This work, performed at the Royal Belgian Institute for Space Aeronomy and the second in a series of four Ozone_cci papers, reports for the first time on data content studies, information content studies, and comparisons with co-located ground-based reference observations for all 13 nadir ozone profile data products that are part of the Climate Research Data Package (CRDP) on atmospheric ozone of the European Space Agency's Climate Change Initiative.
Katerina Garane, Christophe Lerot, Melanie Coldewey-Egbers, Tijl Verhoelst, Maria Elissavet Koukouli, Irene Zyrichidou, Dimitris S. Balis, Thomas Danckaert, Florence Goutail, Jose Granville, Daan Hubert, Arno Keppens, Jean-Christopher Lambert, Diego Loyola, Jean-Pierre Pommereau, Michel Van Roozendael, and Claus Zehner
Atmos. Meas. Tech., 11, 1385–1402, https://doi.org/10.5194/amt-11-1385-2018, https://doi.org/10.5194/amt-11-1385-2018, 2018
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The GOME-type Total Ozone Essential Climate Variable (GTO-ECV) is a level-3 data record, which combines individual sensor products into one single cohesive record covering the 22-year period from 1995 to 2017, generated in the frame of the European Space Agency's Climate Change Initiative Phase II. The exceptional quality of the level-3 GTO-ECV v3 TOC record temporal stability satisfies well the requirements for the total ozone measurement decadal stability of between 1 and 3 %.
Daan Hubert, Jean-Christopher Lambert, Tijl Verhoelst, José Granville, Arno Keppens, Jean-Luc Baray, Adam E. Bourassa, Ugo Cortesi, Doug A. Degenstein, Lucien Froidevaux, Sophie Godin-Beekmann, Karl W. Hoppel, Bryan J. Johnson, Erkki Kyrölä, Thierry Leblanc, Günter Lichtenberg, Marion Marchand, C. Thomas McElroy, Donal Murtagh, Hideaki Nakane, Thierry Portafaix, Richard Querel, James M. Russell III, Jacobo Salvador, Herman G. J. Smit, Kerstin Stebel, Wolfgang Steinbrecht, Kevin B. Strawbridge, René Stübi, Daan P. J. Swart, Ghassan Taha, David W. Tarasick, Anne M. Thompson, Joachim Urban, Joanna A. E. van Gijsel, Roeland Van Malderen, Peter von der Gathen, Kaley A. Walker, Elian Wolfram, and Joseph M. Zawodny
Atmos. Meas. Tech., 9, 2497–2534, https://doi.org/10.5194/amt-9-2497-2016, https://doi.org/10.5194/amt-9-2497-2016, 2016
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A more detailed understanding of satellite O3 profile data records is vital for further progress in O3 research. To this end, we made a comprehensive assessment of 14 limb/occultation profilers using ground-based reference data. The mutual consistency of satellite O3 in terms of bias, short-term variability and decadal stability is generally good over most of the stratosphere. However, we identified some exceptions that impact the quality of recently merged data sets and ozone trend assessments.
M. Coldewey-Egbers, D. G. Loyola, M. Koukouli, D. Balis, J.-C. Lambert, T. Verhoelst, J. Granville, M. van Roozendael, C. Lerot, R. Spurr, S. M. Frith, and C. Zehner
Atmos. Meas. Tech., 8, 3923–3940, https://doi.org/10.5194/amt-8-3923-2015, https://doi.org/10.5194/amt-8-3923-2015, 2015
A. Keppens, J.-C. Lambert, J. Granville, G. Miles, R. Siddans, J. C. A. van Peet, R. J. van der A, D. Hubert, T. Verhoelst, A. Delcloo, S. Godin-Beekmann, R. Kivi, R. Stübi, and C. Zehner
Atmos. Meas. Tech., 8, 2093–2120, https://doi.org/10.5194/amt-8-2093-2015, https://doi.org/10.5194/amt-8-2093-2015, 2015
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This work thoroughly discusses a methodology, as summarized in a flowchart, for the round-robin evaluation and geophysical validation of nadir ozone profile retrievals and applies the proposed best practice to a pair of optimal-estimation algorithms run on exactly the same level-1 radiance measurements. The quality assessment combines data set content studies, information content studies, and comparisons with ground-based reference measurements.
Frederik Tack, Alexis Merlaud, Marian-Daniel Iordache, Gaia Pinardi, Ermioni Dimitropoulou, Henk Eskes, Bart Bomans, Pepijn Veefkind, and Michel Van Roozendael
Atmos. Meas. Tech., 14, 615–646, https://doi.org/10.5194/amt-14-615-2021, https://doi.org/10.5194/amt-14-615-2021, 2021
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We assess the TROPOMI tropospheric NO2 product (OFFL v1.03.01; 3.5 km × 7 km at nadir observations) based on coinciding airborne APEX reference observations (~75 m × 120 m), acquired over polluted regions in Belgium. The TROPOMI NO2 product meets the mission requirements in terms of precision and accuracy. However, we show that TROPOMI is biased low over polluted areas, mainly due to the limited spatial resolution of a priori input for the AMF computation.
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.
Martin Dameris, Diego G. Loyola, Matthias Nützel, Melanie Coldewey-Egbers, Christophe Lerot, Fabian Romahn, and Michel van Roozendael
Atmos. Chem. Phys., 21, 617–633, https://doi.org/10.5194/acp-21-617-2021, https://doi.org/10.5194/acp-21-617-2021, 2021
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Record low ozone values were observed in March 2020. Dynamical and chemical circumstances leading to low ozone values in spring 2020 are discussed and are compared to similar dynamical conditions in the Northern Hemisphere in 1996/1997 and 2010/2011. 2019/2020 showed an unusual persistent polar vortex with low stratospheric temperatures, which were permanently below 195 K at 50 hPa. This enabled enhanced formation of polar stratospheric clouds and a subsequent clear reduction of total ozone.
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.
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.
Viktoria F. Sofieva, Monika Szelag, Johanna Tamminen, Erkki Kyrölä, Doug Degenstein, Chris Roth, Daniel Zawada, Alexei Rozanov, Carlo Arosio, John P. Burrows, Mark Weber, Alexandra Laeng, Gabriele Stiller, Thomas von Clarmann, Lucien Froidevaux, Nathaniel Livesey, Michel van Roozendael, and Christian Retscher
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1117, https://doi.org/10.5194/acp-2020-1117, 2020
Preprint under review for ACP
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The MErged GRIdded Dataset of Ozone Profiles is the long-term (2001–2018) stratospheric ozone profile climate data record with the resolved longitudinal structure, which combines the data from six limb satellite instruments. The dataset can be used various analyses, some of them are discussed in the paper. In particular, regional and vertically resolved ozone trends are evaluated, including the trends in polar regions.
Viktoria F. Sofieva, Hei Shing Lee, Johanna Tamminen, Christophe Lerot, Fabian Romahn, and Diego G. Loyola
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-402, https://doi.org/10.5194/amt-2020-402, 2020
Revised manuscript under review for AMT
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Our paper discusses the structure function method, which allows validation of random uncertainties in the data and, at the same time, probing the small-scale natural variability. We applied this method to the clear-sky total ozone measurements by TROPOMI/Sentinel-5P satellite instrument and found that the TROPOMI random error estimation is adequate. The discussed method is a powerful tool, which can be used in various applications.
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.
Eloise A. Marais, John F. Roberts, Robert G. Ryan, Henk Eskes, K. Folkert Boersma, Sungyeon Choi, Joanna Joiner, Nader Abuhassan, Alberto Redondas, Michel Grutter, Alexander Cede, Laura Gomez, and Monica Navarro-Comas
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-399, https://doi.org/10.5194/amt-2020-399, 2020
Revised manuscript accepted for AMT
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Nitrogen oxides in the upper troposphere have a profound influence on the global troposphere, though observations there are exceedingly rare. We apply cloud-slicing to high spatial resolution TROPOMI total columns of nitrogen dioxide (NO2) to derive near-global observations of upper tropospheric NO2 concentrations and show consistency with existing datasets. These data offer tremendous potential to address knowledge gaps in this oft under-appreciated portion of the atmosphere.
Ermioni Dimitropoulou, François Hendrick, Gaia Pinardi, Martina M. Friedrich, Alexis Merlaud, Frederik Tack, Helene De Longueville, Caroline Fayt, Christian Hermans, Quentin Laffineur, Frans Fierens, and Michel Van Roozendael
Atmos. Meas. Tech., 13, 5165–5191, https://doi.org/10.5194/amt-13-5165-2020, https://doi.org/10.5194/amt-13-5165-2020, 2020
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We present 1 year of dual-scan ground-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements of aerosol and tropospheric NO2 in Uccle (Belgium). Measuring tropospheric NO2 vertical column densities (VCDs) in different azimuthal directions has a positive effect on comparison with measurements from TROPOMI. We prove that the use of inadequate a priori NO2 profile shape data in the TROPOMI retrieval is responsible for the systematic underestimation of S5P NO2 data.
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
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).
Corinne Vigouroux, Bavo Langerock, Carlos Augusto Bauer Aquino, Thomas Blumenstock, Zhibin Cheng, Martine De Mazière, Isabelle De Smedt, Michel Grutter, James W. Hannigan, Nicholas Jones, Rigel Kivi, Diego Loyola, Erik Lutsch, Emmanuel Mahieu, Maria Makarova, Jean-Marc Metzger, Isamu Morino, Isao Murata, Tomoo Nagahama, Justus Notholt, Ivan Ortega, Mathias Palm, Gaia Pinardi, Amelie Röhling, Dan Smale, Wolfgang Stremme, Kim Strong, Ralf Sussmann, Yao Té, Michel van Roozendael, Pucai Wang, and Holger Winkler
Atmos. Meas. Tech., 13, 3751–3767, https://doi.org/10.5194/amt-13-3751-2020, https://doi.org/10.5194/amt-13-3751-2020, 2020
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We validate the TROPOMI HCHO product with ground-based FTIR (Fourier-transform infrared) measurements from 25 stations. We find that TROPOMI overestimates HCHO under clean conditions, while it underestimates it at high HCHO levels. Both TROPOMI precision and accuracy reach the pre-launch requirements, and its precision can even be 2 times better. The observed TROPOMI seasonal variability is in agreement with the FTIR data. The TROPOMI random uncertainty and data filtering should be refined.
Daan Hubert, Klaus-Peter Heue, Jean-Christopher Lambert, Tijl Verhoelst, Marc Allaart, Steven Compernolle, Patrick D. Cullis, Angelika Dehn, Christian Félix, Bryan J. Johnson, Arno Keppens, Debra E. Kollonige, Christophe Lerot, Diego Loyola, Matakite Maata, Sukarni Mitro, Maznorizan Mohamad, Ankie Piters, Fabian Romahn, Henry B. Selkirk, Francisco R. da Silva, Ryan M. Stauffer, Anne M. Thompson, J. Pepijn Veefkind, Holger Vömel, Jacquelyn C. Witte, and Claus Zehner
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-123, https://doi.org/10.5194/amt-2020-123, 2020
Revised manuscript has not been submitted
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We assess the first two years of TROPOMI tropical tropospheric ozone column data. Comparisons to reference measurements by ozonesonde and satellite sensors show that TROPOMI bias (−0.1 to +2.3 DU) and precision (1.5 to 2.5 DU) meet mission requirements. Potential causes of bias and its spatio-temporal structure are discussed, as well as ways to identify sampling errors. The analysis of the known geophysical patterns demonstrates the improved performance of TROPOMI with respect to predecessors.
Steven Compernolle, Athina Argyrouli, Ronny Lutz, Maarten Sneep, Jean-Christopher Lambert, Ann Mari Fjæraa, Daan Hubert, Arno Keppens, Diego Loyola, Ewan O'Connor, Fabian Romahn, Piet Stammes, Tijl Verhoelst, and Ping Wang
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-122, https://doi.org/10.5194/amt-2020-122, 2020
Revised manuscript accepted for AMT
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The high-resolution satellite Sentinel-5p TROPOMI observes several atmospheric gases. To account for cloud interference with the observations, S5P cloud data products (CLOUD OCRA/ROCINN_CAL, OCRA/ROCINN_CRB and FRESCO) provide vital input: cloud fraction, cloud height and cloud optical thickness.
Here, the S5P cloud parameters are validated by comparing with other satellite sensors (VIIRS, MODIS, OMI) and with ground-based CLOUDNET data. The agreement depends on product type and cloud height.
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.
Anne-Marlene Blechschmidt, Joaquim Arteta, Adriana Coman, Lyana Curier, Henk Eskes, Gilles Foret, Clio Gielen, Francois Hendrick, Virginie Marécal, Frédérik Meleux, Jonathan Parmentier, Enno Peters, Gaia Pinardi, Ankie J. M. Piters, Matthieu Plu, Andreas Richter, Arjo Segers, Mikhail Sofiev, Álvaro M. Valdebenito, Michel Van Roozendael, Julius Vira, Tim Vlemmix, and John P. Burrows
Atmos. Chem. Phys., 20, 2795–2823, https://doi.org/10.5194/acp-20-2795-2020, https://doi.org/10.5194/acp-20-2795-2020, 2020
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MAX-DOAS tropospheric NO2 vertical column retrievals from a set of European measurement stations are compared to regional air quality models which contribute to the operational Copernicus Atmosphere Monitoring Service (CAMS). Correlations are on the order of 35 %–75 %; large differences occur for individual pollution plumes. The results demonstrate that future model development needs to concentrate on improving representation of diurnal cycles and associated temporal scalings.
Song Liu, Pieter Valks, Gaia Pinardi, Jian Xu, Athina Argyrouli, Ronny Lutz, L. Gijsbert Tilstra, Vincent Huijnen, François Hendrick, and Michel Van Roozendael
Atmos. Meas. Tech., 13, 755–787, https://doi.org/10.5194/amt-13-755-2020, https://doi.org/10.5194/amt-13-755-2020, 2020
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This paper presents an improved tropospheric nitrogen dioxide (NO2) retrieval algorithm from the Global Ozone Monitoring Experiment-2 (GOME-2) instrument based on air mass factor (AMF) calculations that are
performed with a more accurate knowledge of surface albedo, the a priori NO2 profile, and cloud and aerosol corrections.
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.
Katerina Garane, Maria-Elissavet Koukouli, Tijl Verhoelst, Christophe Lerot, Klaus-Peter Heue, Vitali Fioletov, Dimitrios Balis, Alkiviadis Bais, Ariane Bazureau, Angelika Dehn, Florence Goutail, Jose Granville, Debora Griffin, Daan Hubert, Arno Keppens, Jean-Christopher Lambert, Diego Loyola, Chris McLinden, Andrea Pazmino, Jean-Pierre Pommereau, Alberto Redondas, Fabian Romahn, Pieter Valks, Michel Van Roozendael, Jian Xu, Claus Zehner, Christos Zerefos, and Walter Zimmer
Atmos. Meas. Tech., 12, 5263–5287, https://doi.org/10.5194/amt-12-5263-2019, https://doi.org/10.5194/amt-12-5263-2019, 2019
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The Sentinel-5 Precursor TROPOMI near real time (NRTI) and offline (OFFL) total ozone column (TOC) products are validated against direct-sun and twilight zenith-sky ground-based TOC measurements and other already known spaceborne sensors. The results show that the TROPOMI TOC measurements are in very good agreement with the ground-based measurements and satellite sensor measurements and that they are well within the product requirements.
Arno Keppens, Steven Compernolle, Tijl Verhoelst, Daan Hubert, and Jean-Christopher Lambert
Atmos. Meas. Tech., 12, 4379–4391, https://doi.org/10.5194/amt-12-4379-2019, https://doi.org/10.5194/amt-12-4379-2019, 2019
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This work discusses the most frequent methods for the harmonization of vertically resolved atmospheric state observations in a conceptually and terminologically aligned framework. Ten matching operations have been identified and expressed by common matrix algebra. The effect of these manipulations on the information content of the original data and on the uncertainty budget of data comparisons has been examined and discussed.
Hyeong-Ahn Kwon, Rokjin J. Park, Gonzalo González Abad, Kelly Chance, Thomas P. Kurosu, Jhoon Kim, Isabelle De Smedt, Michel Van Roozendael, Enno Peters, and John Burrows
Atmos. Meas. Tech., 12, 3551–3571, https://doi.org/10.5194/amt-12-3551-2019, https://doi.org/10.5194/amt-12-3551-2019, 2019
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The Geostationary Environment Monitoring Spectrometer (GEMS) will be launched by South Korea in 2019, and it will measure radiances ranging from 300 to 500 nm every hour with a fine spatial resolution of 7 km x 8 km over Seoul in South Korea to monitor column concentrations of air pollutants including O3, NO2, SO2, and HCHO, as well as aerosol optical properties. This paper describes a GEMS formaldehyde retrieval algorithm including a number of sensitivity tests for algorithm evaluation.
Jean-Pierre Pommereau, Florence Goutail, René Stübi, and Geir Braathen
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2019-211, https://doi.org/10.5194/amt-2019-211, 2019
Publication in AMT not foreseen
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.
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.
Raid M. Suleiman, Kelly Chance, Xiong Liu, Gonzalo González Abad, Thomas P. Kurosu, Francois Hendrick, and Nicolas Theys
Atmos. Meas. Tech., 12, 2067–2084, https://doi.org/10.5194/amt-12-2067-2019, https://doi.org/10.5194/amt-12-2067-2019, 2019
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This paper presents the retrieval algorithm for the operational OMBRO data product and shows comparisons with correlative measurements and retrieval results. We highlight the physics of the retrieval. We compare the OMBRO products with other satellite and in situ measurements of BrO and illustrate the quality of the product on a global scale. We study OMBRO enhancements in volcanic plumes and over salt lakes. We also discuss the shortcomings and future updates of the OMBRO product.
Antje Inness, Johannes Flemming, Klaus-Peter Heue, Christophe Lerot, Diego Loyola, Roberto Ribas, Pieter Valks, Michel van Roozendael, Jian Xu, and Walter Zimmer
Atmos. Chem. Phys., 19, 3939–3962, https://doi.org/10.5194/acp-19-3939-2019, https://doi.org/10.5194/acp-19-3939-2019, 2019
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This paper documents the use of total column ozone data from the TROPOMI satellite in the global forecasting system of the Copernicus Atmosphere Monitoring Service (CAMS). The data are of good quality over large parts of the globe but have some issues at high latitudes, at low solar elevations and over snow/ice. Assimilating the data in the CAMS system has a small positive impact, especially in the tropical troposphere.
Kostas Eleftheratos, Christos S. Zerefos, Dimitris S. Balis, Maria-Elissavet Koukouli, John Kapsomenakis, Diego G. Loyola, Pieter Valks, Melanie Coldewey-Egbers, Christophe Lerot, Stacey M. Frith, Amund S. Haslerud, Ivar S. A. Isaksen, and Seppo Hassinen
Atmos. Meas. Tech., 12, 987–1011, https://doi.org/10.5194/amt-12-987-2019, https://doi.org/10.5194/amt-12-987-2019, 2019
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We examine the ability of GOME-2A total ozone data to capture variability related to known natural oscillations, such as the QBO, ENSO and NAO, with respect to other satellite datasets, ground-based data, and chemical transport model simulations. The analysis is based on the GOME-2 satellite total ozone columns for the period 2007–2016 which form part of the operational EUMETSAT AC SAF GOME-2 MetOp A GDP4.8 latest data product.
Rosa Delia García, Emilio Cuevas, Ramón Ramos, Victoria Eugenia Cachorro, Alberto Redondas, and José A. Moreno-Ruiz
Geosci. Instrum. Method. Data Syst., 8, 77–96, https://doi.org/10.5194/gi-8-77-2019, https://doi.org/10.5194/gi-8-77-2019, 2019
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IZA is a high-mountain station located in Tenerife (Canary Islands, Spain, at 28.3º N, 16.5º W; 2373 m a.s.l.) and is a representative site of the subtropical North Atlantic free troposphere. It contributes with basic-BSRN radiation measurements, such as, global shortwave radiation, direct radiation, diffuse radiation and longwave downward radiation and extended-BSRN measurements, including ultraviolet ranges, shortwave upward radiation and longwave upward radiation.
Frederik Tack, Alexis Merlaud, Andreas C. Meier, Tim Vlemmix, Thomas Ruhtz, Marian-Daniel Iordache, Xinrui Ge, Len van der Wal, Dirk Schuettemeyer, Magdalena Ardelean, Andreea Calcan, Daniel Constantin, Anja Schönhardt, Koen Meuleman, Andreas Richter, and Michel Van Roozendael
Atmos. Meas. Tech., 12, 211–236, https://doi.org/10.5194/amt-12-211-2019, https://doi.org/10.5194/amt-12-211-2019, 2019
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We present an intercomparison study of four airborne imaging DOAS instruments, dedicated to the retrieval and high-resolution mapping of tropospheric nitrogen dioxide (NO2) vertical column densities (VCDs). The AROMAPEX campaign took place in Berlin, Germany, in April 2016 with the primary objectives (1) to test and intercompare the performance of experimental airborne imagers and (2) to prepare the validation and calibration campaigns for the Sentinel-5 Precursor/TROPOMI mission.
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.
Ting Wang, Pucai Wang, Nicolas Theys, Dan Tong, François Hendrick, Qiang Zhang, and Michel Van Roozendael
Atmos. Chem. Phys., 18, 18063–18078, https://doi.org/10.5194/acp-18-18063-2018, https://doi.org/10.5194/acp-18-18063-2018, 2018
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In the last decade, four temporal regimes of SO2 in China have been identified. After an initial rise, SO2 undergoes two sharp drops in 2007–2008 and 2014–2016, during which 5-year rebounding is sustained. Different mechanisms are tied to North and South China. The industrial emission is responsible for SO2 variation in North China, while in South China the meteorological conditions make a large contribution. The result is crucial to the understanding of SO2 changes and future polices.
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.
Hansen Cao, Tzung-May Fu, Lin Zhang, Daven K. Henze, Christopher Chan Miller, Christophe Lerot, Gonzalo González Abad, Isabelle De Smedt, Qiang Zhang, Michel van Roozendael, François Hendrick, Kelly Chance, Jie Li, Junyu Zheng, and Yuanhong Zhao
Atmos. Chem. Phys., 18, 15017–15046, https://doi.org/10.5194/acp-18-15017-2018, https://doi.org/10.5194/acp-18-15017-2018, 2018
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Our top-down estimates for annual total Chinese NMVOC emissions was 30.7 to 49.5 Tg y−1, including 16.4 to 23.6 Tg y−1 from anthropogenic sources, 12.2 to 22.8 Tg y−1 from biogenic sources, and 2.08 to 3.13 Tg y−1 from biomass burning. Our four inversions consistently showed that the emissions of Chinese anthropogenic NMVOC precursors of glyoxal were larger than the a priori estimates. The glyoxal and formaldehyde constraints helped distinguish the NMVOC species from different sources.
Anne Boynard, Daniel Hurtmans, Katerina Garane, Florence Goutail, Juliette Hadji-Lazaro, Maria Elissavet Koukouli, Catherine Wespes, Corinne Vigouroux, Arno Keppens, Jean-Pierre Pommereau, Andrea Pazmino, Dimitris Balis, Diego Loyola, Pieter Valks, Ralf Sussmann, Dan Smale, Pierre-François Coheur, and Cathy Clerbaux
Atmos. Meas. Tech., 11, 5125–5152, https://doi.org/10.5194/amt-11-5125-2018, https://doi.org/10.5194/amt-11-5125-2018, 2018
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In this paper, we perform a comprehensive validation of the IASI/Metop ozone data using independent observations (satellite, ground-based and ozonesonde). The quality of the IASI total and tropospheric ozone columns in terms of bias and long-term stability is generally good. Compared with ozonesonde data, IASI overestimates (underestimates) the ozone abundance in the stratosphere (troposphere). A negative drift in tropospheric ozone is observed, which is not well understood at this point.
John S. Rimmer, Alberto Redondas, and Tomi Karppinen
Atmos. Chem. Phys., 18, 10347–10353, https://doi.org/10.5194/acp-18-10347-2018, https://doi.org/10.5194/acp-18-10347-2018, 2018
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The Vienna Convention to Protect the Ozone Layer was signed in 1985 to promote research and information exchange on the science of ozone depletion including monitoring of total ozone column and spectrally resolved solar ultraviolet radiation. This is a global challenge and, as such, all efforts to gather data should be consistent. This work has resulted in a framework for all Brewer Ozone spectrophotometers to provide data in a consistent way in terms of calibration and quality assurance.
Sergio Fabián León-Luis, Alberto Redondas, Virgilio Carreño, Javier López-Solano, Alberto Berjón, Bentorey Hernández-Cruz, and Daniel Santana-Díaz
Atmos. Meas. Tech., 11, 4059–4072, https://doi.org/10.5194/amt-11-4059-2018, https://doi.org/10.5194/amt-11-4059-2018, 2018
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In 2003, the Regional Brewer Calibration Center for Europe (RBCC-E) was established at the Izaña Atmospheric Research Center and since 2011 the RBCC-E transfers its calibration based on Langley using travelling standard(s) that are absolutely and independently calibrated at Izaña. This work is focused on reporting on the consistency of the measurements of the RBCC-E triad (Brewers #157, #183 and #185) made during the period 2005–2016.
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.
Alberto Redondas, Virgilio Carreño, Sergio F. León-Luis, Bentorey Hernández-Cruz, Javier López-Solano, Juan J. Rodriguez-Franco, José M. Vilaplana, Julian Gröbner, John Rimmer, Alkiviadis F. Bais, Vladimir Savastiouk, Juan R. Moreta, Lamine Boulkelia, Nis Jepsen, Keith M. Wilson, Vadim Shirotov, and Tomi Karppinen
Atmos. Chem. Phys., 18, 9441–9455, https://doi.org/10.5194/acp-18-9441-2018, https://doi.org/10.5194/acp-18-9441-2018, 2018
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This work shows an overview of the total ozone comparison of the Brewer instrument during the 10th RBCC-E campaign in a joint effort with the EUBREWNET COST 1207 action. The status of the network after 2 years of calibration shows 16 out of the 21 participating Brewer instruments (76 %) agreed within better than ±1 %, and 10 instruments (50 %) agreed within better than ±0.5 %. After applying the final calibration and the stray light correction all working instruments agreed at the ±0.5 % level.
Arno Keppens, Jean-Christopher Lambert, José Granville, Daan Hubert, Tijl Verhoelst, Steven Compernolle, Barry Latter, Brian Kerridge, Richard Siddans, Anne Boynard, Juliette Hadji-Lazaro, Cathy Clerbaux, Catherine Wespes, Daniel R. Hurtmans, Pierre-François Coheur, Jacob C. A. van Peet, Ronald J van der A, Katerina Garane, Maria Elissavet Koukouli, Dimitris S. Balis, Andy Delcloo, Rigel Kivi, Réné Stübi, Sophie Godin-Beekmann, Michel Van Roozendael, and Claus Zehner
Atmos. Meas. Tech., 11, 3769–3800, https://doi.org/10.5194/amt-11-3769-2018, https://doi.org/10.5194/amt-11-3769-2018, 2018
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This work, performed at the Royal Belgian Institute for Space Aeronomy and the second in a series of four Ozone_cci papers, reports for the first time on data content studies, information content studies, and comparisons with co-located ground-based reference observations for all 13 nadir ozone profile data products that are part of the Climate Research Data Package (CRDP) on atmospheric ozone of the European Space Agency's Climate Change Initiative.
Alberto Redondas, Saulius Nevas, Alberto Berjón, Meelis-Mait Sildoja, Sergio Fabian León-Luis, Virgilio Carreño, and Daniel Santana-Díaz
Atmos. Meas. Tech., 11, 3759–3768, https://doi.org/10.5194/amt-11-3759-2018, https://doi.org/10.5194/amt-11-3759-2018, 2018
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We present the wavelength calibration of the travelling reference Brewer spectrometer of the Regional Brewer Calibration Center for Europe at PTB in Braunschweig. We compare these results to those of the standard procedure for the wavelength calibration of the Brewer. The results of the laser-based calibrations reproduce those obtained by the standard operational methodology and show that there is a underestimation of 0.8 %, due the use of the parametrized slit functions.
Rosa Delia García, Africa Barreto, Emilio Cuevas, Julian Gröbner, Omaira Elena García, Angel Gómez-Peláez, Pedro Miguel Romero-Campos, Alberto Redondas, Victoria Eugenia Cachorro, and Ramon Ramos
Geosci. Model Dev., 11, 2139–2152, https://doi.org/10.5194/gmd-11-2139-2018, https://doi.org/10.5194/gmd-11-2139-2018, 2018
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A 7-year comparison study between measured and simulated longwave
downward radiation under cloud-free conditions has been performed at BSRN Izaña. Results show an excellent agreement with a mean bias (simulated–measured) less than 1.1 % and RMSE less than 1 %, which are within the instrumental error (2 %).
Alberto Berjón, Alberto Redondas, Meelis-Mait Sildoja, Saulius Nevas, Keith Wilson, Sergio F. León-Luis, Omar el Gawhary, and Ilias Fountoulakis
Atmos. Meas. Tech., 11, 3323–3337, https://doi.org/10.5194/amt-11-3323-2018, https://doi.org/10.5194/amt-11-3323-2018, 2018
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The Brewer spectrophotometer has been used for decades as reference instrument to retrieve total ozone column (TOC) and for validation of satellite based measurements. This spectrophotometer has a thermal sensitivity already known, which is usually characterized using two different retrieval procedures. In this work, we report on a comparative study of the temperature coefficients retrieval procedures, obtaining differences less that 0.08 % in TOC when using any of the procedures.
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.
Ulf Köhler, Saulius Nevas, Glen McConville, Robert Evans, Marek Smid, Martin Stanek, Alberto Redondas, and Fritz Schönenborn
Atmos. Meas. Tech., 11, 1989–1999, https://doi.org/10.5194/amt-11-1989-2018, https://doi.org/10.5194/amt-11-1989-2018, 2018
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Laboratory investigations of optical characteristics of three standard Dobsons provide real wavelength settings and slit functions. These parameters were compared with the original values given in the manuals. The differences between real and nominal values are not too large, but their application will in any case improve the quality of the total ozone column measurements in the global
network. This improvement was the main objective of the ATMOZ project funding these activities.
Javier López-Solano, Alberto Redondas, Thomas Carlund, Juan J. Rodriguez-Franco, Henri Diémoz, Sergio F. León-Luis, Bentorey Hernández-Cruz, Carmen Guirado-Fuentes, Natalia Kouremeti, Julian Gröbner, Stelios Kazadzis, Virgilio Carreño, Alberto Berjón, Daniel Santana-Díaz, Manuel Rodríguez-Valido, Veerle De Bock, Juan R. Moreta, John Rimmer, Andrew R. D. Smedley, Lamine Boulkelia, Nis Jepsen, Paul Eriksen, Alkiviadis F. Bais, Vadim Shirotov, José M. Vilaplana, Keith M. Wilson, and Tomi Karppinen
Atmos. Chem. Phys., 18, 3885–3902, https://doi.org/10.5194/acp-18-3885-2018, https://doi.org/10.5194/acp-18-3885-2018, 2018
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The European Brewer Network (EUBREWNET, COST Action ES1207) is comprised of close to 50 instruments and currently provides near-real-time ozone and UV data. Aerosols also play key role in the Earth–atmosphere system and introduce a large uncertainty into our understanding of climate change. In this work we describe and validate a method to incorporate the measurement of aerosols in EUBREWNET. We find that this Brewer network can provide reliable aerosol data across Europe in the UV range.
Katerina Garane, Christophe Lerot, Melanie Coldewey-Egbers, Tijl Verhoelst, Maria Elissavet Koukouli, Irene Zyrichidou, Dimitris S. Balis, Thomas Danckaert, Florence Goutail, Jose Granville, Daan Hubert, Arno Keppens, Jean-Christopher Lambert, Diego Loyola, Jean-Pierre Pommereau, Michel Van Roozendael, and Claus Zehner
Atmos. Meas. Tech., 11, 1385–1402, https://doi.org/10.5194/amt-11-1385-2018, https://doi.org/10.5194/amt-11-1385-2018, 2018
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The GOME-type Total Ozone Essential Climate Variable (GTO-ECV) is a level-3 data record, which combines individual sensor products into one single cohesive record covering the 22-year period from 1995 to 2017, generated in the frame of the European Space Agency's Climate Change Initiative Phase II. The exceptional quality of the level-3 GTO-ECV v3 TOC record temporal stability satisfies well the requirements for the total ozone measurement decadal stability of between 1 and 3 %.
Alexis Merlaud, Frederik Tack, Daniel Constantin, Lucian Georgescu, Jeroen Maes, Caroline Fayt, Florin Mingireanu, Dirk Schuettemeyer, Andreas Carlos Meier, Anja Schönardt, Thomas Ruhtz, Livio Bellegante, Doina Nicolae, Mirjam Den Hoed, Marc Allaart, and Michel Van Roozendael
Atmos. Meas. Tech., 11, 551–567, https://doi.org/10.5194/amt-11-551-2018, https://doi.org/10.5194/amt-11-551-2018, 2018
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We present SWING-UAV, an atmospheric observation system based on a compact scanning spectrometer (SWING) mounted on an unmanned aerial vehicle (UAV). SWING-UAV was operated in the exhaust plume of a power plant in Romania in September 2014, during the AROMAT campaign. SWING quantified the NO2 emitted by the plant and the water vapour content in the boundary layer, in agreement with ancillary data. The system appears in particular promising to study emissions in rural areas.
Ilias Fountoulakis, Alberto Redondas, Kaisa Lakkala, Alberto Berjon, Alkiviadis F. Bais, Lionel Doppler, Uwe Feister, Anu Heikkila, Tomi Karppinen, Juha M. Karhu, Tapani Koskela, Katerina Garane, Konstantinos Fragkos, and Volodya Savastiouk
Atmos. Meas. Tech., 10, 4491–4505, https://doi.org/10.5194/amt-10-4491-2017, https://doi.org/10.5194/amt-10-4491-2017, 2017
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Results of the temperature characterization of the global UV spectral measurements of eight different Brewer spectrophotometers operating in Greece, Finland, Germany and Spain are presented. Different temperature characterization methods are evaluated and an improved methodology for the correction of the measurements for the effects of temperature is presented.
Viktoria F. Sofieva, Erkki Kyrölä, Marko Laine, Johanna Tamminen, Doug Degenstein, Adam Bourassa, Chris Roth, Daniel Zawada, Mark Weber, Alexei Rozanov, Nabiz Rahpoe, Gabriele Stiller, Alexandra Laeng, Thomas von Clarmann, Kaley A. Walker, Patrick Sheese, Daan Hubert, Michel van Roozendael, Claus Zehner, Robert Damadeo, Joseph Zawodny, Natalya Kramarova, and Pawan K. Bhartia
Atmos. Chem. Phys., 17, 12533–12552, https://doi.org/10.5194/acp-17-12533-2017, https://doi.org/10.5194/acp-17-12533-2017, 2017
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We present a merged dataset of ozone profiles from several satellite instruments: SAGE II, GOMOS, SCIAMACHY, MIPAS, OSIRIS, ACE-FTS and OMPS. For merging, we used the latest versions of the original ozone datasets.
The merged SAGE–CCI–OMPS dataset is used for evaluating ozone trends in the stratosphere through multiple linear regression. Negative ozone trends in the upper stratosphere are observed before 1997 and positive trends are found after 1997.
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.
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.
Frederik Tack, Alexis Merlaud, Marian-Daniel Iordache, Thomas Danckaert, Huan Yu, Caroline Fayt, Koen Meuleman, Felix Deutsch, Frans Fierens, and Michel Van Roozendael
Atmos. Meas. Tech., 10, 1665–1688, https://doi.org/10.5194/amt-10-1665-2017, https://doi.org/10.5194/amt-10-1665-2017, 2017
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This paper presents retrieval results of NO2 vertical column densities mapped at high spatial resolution over three Belgian cities, based on the DOAS analysis of Airborne APEX observations. A major objective of the study is to assess the technical and operational capabilities of the APEX hyperspectral pushbroom imager to map the NO2 horizontal distribution field over urbanised areas.
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.
Michael P. Barkley, Gonzalo González Abad, Thomas P. Kurosu, Robert Spurr, Sara Torbatian, and Christophe Lerot
Atmos. Chem. Phys., 17, 4687–4709, https://doi.org/10.5194/acp-17-4687-2017, https://doi.org/10.5194/acp-17-4687-2017, 2017
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Using Ozone Monitoring Instrument (OMI) trace gas vertical column observations of NO2, HCHO, SO2, and CHOCHO, we have conducted a robust and detailed time series analysis to assess changes in local air quality for over 1000 locations (focussing on urban, oil refinery, oil port, and power plant targets) over the Middle East for 2005–2014. We find that for many locations in the Middle East, OMI observes a degradation in air quality during this time period.
Christopher E. Sioris, Landon A. Rieger, Nicholas D. Lloyd, Adam E. Bourassa, Chris Z. Roth, Douglas A. Degenstein, Claude Camy-Peyret, Klaus Pfeilsticker, Gwenaël Berthet, Valéry Catoire, Florence Goutail, Jean-Pierre Pommereau, and Chris A. McLinden
Atmos. Meas. Tech., 10, 1155–1168, https://doi.org/10.5194/amt-10-1155-2017, https://doi.org/10.5194/amt-10-1155-2017, 2017
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A new OSIRIS NO2 retrieval algorithm is described and validated using > 40 balloon-based profile measurements. The validation results indicate a slight improvement relative to the existing operational algorithm in terms of the bias versus the balloon data, particularly in the lower stratosphere. The implication is that this new algorithm should replace the operational one. The motivation was to combine spectral fitting and the SaskTRAN radiative transfer model to achieve an improved product.
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.
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.
Christos S. Zerefos, Kostas Eleftheratos, John Kapsomenakis, Stavros Solomos, Antje Inness, Dimitris Balis, Alberto Redondas, Henk Eskes, Marc Allaart, Vassilis Amiridis, Arne Dahlback, Veerle De Bock, Henri Diémoz, Ronny Engelmann, Paul Eriksen, Vitali Fioletov, Julian Gröbner, Anu Heikkilä, Irina Petropavlovskikh, Janusz Jarosławski, Weine Josefsson, Tomi Karppinen, Ulf Köhler, Charoula Meleti, Christos Repapis, John Rimmer, Vladimir Savinykh, Vadim Shirotov, Anna Maria Siani, Andrew R. D. Smedley, Martin Stanek, and René Stübi
Atmos. Chem. Phys., 17, 551–574, https://doi.org/10.5194/acp-17-551-2017, https://doi.org/10.5194/acp-17-551-2017, 2017
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The paper makes a convincing case that the Brewer network is capable of detecting enhanced SO2 columns, as observed, e.g., after volcanic eruptions. For this reason, large volcanic eruptions of the past decade have been used to detect and forecast SO2 plumes of volcanic origin using the Brewer and other ground-based networks, aided by satellite, trajectory analysis calculations and modelling.
Clio Gielen, François Hendrick, Gaia Pinardi, Isabelle De Smedt, Caroline Fayt, Christian Hermans, Trissevgeni Stavrakou, Maite Bauwens, Jean-Francois Müller, Eugène Ndenzako, Pierre Nzohabonayo, Rachel Akimana, Sebastien Niyonzima, Michel Van Roozendael, and Martine De Mazière
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2016-1104, https://doi.org/10.5194/acp-2016-1104, 2017
Revised manuscript has not been submitted
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In this paper we study the composition of the lower atmosphere above the Central-African capital city of Burundi (Bujumbura) by measuring the amount of aerosol dust particles and trace gases in the air.
We find that the aerosol and trace gas seasonal and daily variation is driven by the alternation of rain periods and dry periods associated with intense biomass burning in the vicinity of Bujumbura, and the influence of human activities in the city center.
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.
Klaus-Peter Heue, Melanie Coldewey-Egbers, Andy Delcloo, Christophe Lerot, Diego Loyola, Pieter Valks, and Michel van Roozendael
Atmos. Meas. Tech., 9, 5037–5051, https://doi.org/10.5194/amt-9-5037-2016, https://doi.org/10.5194/amt-9-5037-2016, 2016
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The tropical tropospheric column ozone (TCO) from 5 GOME-type satellite instruments were harmonised to get a consistent time series of tropospheric ozone for 20 years. The time series showed a global ozone trend below 10 km of 0.7 DU per decade. Also the regional trends were analysed and trends up to 1.8 DU per decade or decreases as low as 0.8 DU per decade were observed. The TCO will be part of the operation product for Tropomi/S5P and thereby extended for at least 7 years.
Sergey M. Khaykin, Jean-Pierre Pommereau, Emmanuel D. Riviere, Gerhard Held, Felix Ploeger, Melanie Ghysels, Nadir Amarouche, Jean-Paul Vernier, Frank G. Wienhold, and Dmitry Ionov
Atmos. Chem. Phys., 16, 12273–12286, https://doi.org/10.5194/acp-16-12273-2016, https://doi.org/10.5194/acp-16-12273-2016, 2016
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The study makes use of a series of field experiments conducted in Brazil and aimed at studying the processes controlling the composition of the tropical lower stratosphere. High-resolution balloon-borne measurements together with global-coverage satellite observations and weather radar acquisitions are analysed using trajectory and transport modelling in order to evaluate the contribution of different transport pathways to the stratospheric water budget.
Anne Boynard, Daniel Hurtmans, Mariliza E. Koukouli, Florence Goutail, Jérôme Bureau, Sarah Safieddine, Christophe Lerot, Juliette Hadji-Lazaro, Catherine Wespes, Jean-Pierre Pommereau, Andrea Pazmino, Irene Zyrichidou, Dimitris Balis, Alain Barbe, Semen N. Mikhailenko, Diego Loyola, Pieter Valks, Michel Van Roozendael, Pierre-François Coheur, and Cathy Clerbaux
Atmos. Meas. Tech., 9, 4327–4353, https://doi.org/10.5194/amt-9-4327-2016, https://doi.org/10.5194/amt-9-4327-2016, 2016
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Seven years of O3 observations retrieved from IASI/MetOp satellite instruments are validated with independent data (UV satellite and ground-based data along with ozonesonde profiles). Overall IASI overestimates the total ozone columns (TOC) by 2–7 % depending on the latitude. The assessment of an updated version of the IASI O3 retrieval sofware shows a correction of ~ 4 % in the IASI TOC product, bringing the overall global bias with UV ground-based and satellite data to ~ 1–2 % on average.
Marie Boichu, Isabelle Chiapello, Colette Brogniez, Jean-Christophe Péré, Francois Thieuleux, Benjamin Torres, Luc Blarel, Augustin Mortier, Thierry Podvin, Philippe Goloub, Nathalie Söhne, Lieven Clarisse, Sophie Bauduin, François Hendrick, Nicolas Theys, Michel Van Roozendael, and Didier Tanré
Atmos. Chem. Phys., 16, 10831–10845, https://doi.org/10.5194/acp-16-10831-2016, https://doi.org/10.5194/acp-16-10831-2016, 2016
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Bárðarbunga eruption emitted huge amounts of sulfur into the lower troposphere causing an unprecedented air pollution in the modern era. A wealth of remote sensing and in situ data allows us to jointly analyse the dynamics of volcanic SO2 and sulfate aerosols. Based on this panel of observations, success and challenges in simulating such volcanogenic long-range pollution events are exposed, focusing on the boundary layer dynamics.
Maite Bauwens, Trissevgeni Stavrakou, Jean-François Müller, Isabelle De Smedt, Michel Van Roozendael, Guido R. van der Werf, Christine Wiedinmyer, Johannes W. Kaiser, Katerina Sindelarova, and Alex Guenther
Atmos. Chem. Phys., 16, 10133–10158, https://doi.org/10.5194/acp-16-10133-2016, https://doi.org/10.5194/acp-16-10133-2016, 2016
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Relying on a 9-year record of satellite observations of formaldehyde, we use inverse techniques to derive global top–down hydrocarbon fluxes over 2005–2013, infer seasonal and interannual variability, and detect emission trends. Our results suggest changes in fire seasonal patterns, a stronger contribution of agricultural burning, overestimated isoprene flux rates in the tropics, overly decreased isoprene emissions due to soil moisture stress in arid areas, and enhanced isoprene trends.
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.
Daan Hubert, Jean-Christopher Lambert, Tijl Verhoelst, José Granville, Arno Keppens, Jean-Luc Baray, Adam E. Bourassa, Ugo Cortesi, Doug A. Degenstein, Lucien Froidevaux, Sophie Godin-Beekmann, Karl W. Hoppel, Bryan J. Johnson, Erkki Kyrölä, Thierry Leblanc, Günter Lichtenberg, Marion Marchand, C. Thomas McElroy, Donal Murtagh, Hideaki Nakane, Thierry Portafaix, Richard Querel, James M. Russell III, Jacobo Salvador, Herman G. J. Smit, Kerstin Stebel, Wolfgang Steinbrecht, Kevin B. Strawbridge, René Stübi, Daan P. J. Swart, Ghassan Taha, David W. Tarasick, Anne M. Thompson, Joachim Urban, Joanna A. E. van Gijsel, Roeland Van Malderen, Peter von der Gathen, Kaley A. Walker, Elian Wolfram, and Joseph M. Zawodny
Atmos. Meas. Tech., 9, 2497–2534, https://doi.org/10.5194/amt-9-2497-2016, https://doi.org/10.5194/amt-9-2497-2016, 2016
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A more detailed understanding of satellite O3 profile data records is vital for further progress in O3 research. To this end, we made a comprehensive assessment of 14 limb/occultation profilers using ground-based reference data. The mutual consistency of satellite O3 in terms of bias, short-term variability and decadal stability is generally good over most of the stratosphere. However, we identified some exceptions that impact the quality of recently merged data sets and ozone trend assessments.
Omaira Elena García, Eliezer Sepúlveda, Matthias Schneider, Frank Hase, Thomas August, Thomas Blumenstock, Sven Kühl, Rosemary Munro, Ángel Jesús Gómez-Peláez, Tim Hultberg, Alberto Redondas, Sabine Barthlott, Andreas Wiegele, Yenny González, and Esther Sanromá
Atmos. Meas. Tech., 9, 2315–2333, https://doi.org/10.5194/amt-9-2315-2016, https://doi.org/10.5194/amt-9-2315-2016, 2016
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Atmospheric remote sounding from space is fundamental for investigating the processes driving climate change. However, for a correct scientific interpretation of these records a documentation of their quality is required. In this context, this paper exploits the high potential of the Izaña Atmospheric Observatory, as a ground-based reference site, to perform the first comprehensive validation of the EUMETSAT atmospheric trace gas products O3, CH4, N2O, CO and CO2 of the remote sensor IASI.
Maria Elissavet Koukouli, Marina Zara, Christophe Lerot, Konstantinos Fragkos, Dimitris Balis, Michel van Roozendael, Marcus Antonius Franciscus Allart, and Ronald Johannes van der A
Atmos. Meas. Tech., 9, 2055–2065, https://doi.org/10.5194/amt-9-2055-2016, https://doi.org/10.5194/amt-9-2055-2016, 2016
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The main aim of the paper is to demonstrate an approach for the post-processing of the Dobson spectrophotometers' total ozone columns (TOCs) in order to compensate for their known stratospheric effective temperature dependency
and its resulting effect on the usage of the Dobson TOCs for satellite TOCs' validation.
Ilias Fountoulakis, Alberto Redondas, Alkiviadis F. Bais, Juan José Rodriguez-Franco, Konstantinos Fragkos, and Alexander Cede
Atmos. Meas. Tech., 9, 1799–1816, https://doi.org/10.5194/amt-9-1799-2016, https://doi.org/10.5194/amt-9-1799-2016, 2016
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The dead time (DT) is characteristic for each Brewer spectrophotometer and non-proper correction of the raw data for its effect may lead to important errors in UV, AOD and TOC measurements. Quantitative estimation of the DT-related uncertainties shown that a 2 ns error in the DT may lead to errors greater than 1 % in TOC. The operational algorithm for the DT calculation and correction is validated and the development of new methods for the estimation of DT is described.
Mélanie Ghysels, Emmanuel D. Riviere, Sergey Khaykin, Clara Stoeffler, Nadir Amarouche, Jean-Pierre Pommereau, Gerhard Held, and Georges Durry
Atmos. Meas. Tech., 9, 1207–1219, https://doi.org/10.5194/amt-9-1207-2016, https://doi.org/10.5194/amt-9-1207-2016, 2016
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Water vapor in the Earth stratosphere has a significant impact on the climate and the radiative balance. Achieving high-accuracy measurements of humidity in the stratosphere is still far from routine. In this paper, we demonstrate one of the best in situ balloon-borne measurement comparisons from two highly compact spectrometers: Pico-SDLA H2O and FLASH-B.
D. Toledo, P. Rannou, J.-P. Pommereau, A. Sarkissian, and T. Foujols
Atmos. Meas. Tech., 9, 455–467, https://doi.org/10.5194/amt-9-455-2016, https://doi.org/10.5194/amt-9-455-2016, 2016
S. Hassinen, D. Balis, H. Bauer, M. Begoin, A. Delcloo, K. Eleftheratos, S. Gimeno Garcia, J. Granville, M. Grossi, N. Hao, P. Hedelt, F. Hendrick, M. Hess, K.-P. Heue, J. Hovila, H. Jønch-Sørensen, N. Kalakoski, A. Kauppi, S. Kiemle, L. Kins, M. E. Koukouli, J. Kujanpää, J.-C. Lambert, R. Lang, C. Lerot, D. Loyola, M. Pedergnana, G. Pinardi, F. Romahn, M. van Roozendael, R. Lutz, I. De Smedt, P. Stammes, W. Steinbrecht, J. Tamminen, N. Theys, L. G. Tilstra, O. N. E. Tuinder, P. Valks, C. Zerefos, W. Zimmer, and I. Zyrichidou
Atmos. Meas. Tech., 9, 383–407, https://doi.org/10.5194/amt-9-383-2016, https://doi.org/10.5194/amt-9-383-2016, 2016
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The three GOME-2 instruments will provide unique and long data sets for atmospheric research and applications. The complete time period will be 2007–2022, including the period of ozone depletion as well as the beginning of ozone layer recovery. The GOME-2 products (ozone, trace gases, aerosols and UV radiation) are important for ozone chemistry, air quality studies, climate modeling, policy monitoring and hazard warnings. The processing and dissemination is done by EUMETSAT O3M SAF project.
I. De Smedt, T. Stavrakou, F. Hendrick, T. Danckaert, T. Vlemmix, G. Pinardi, N. Theys, C. Lerot, C. Gielen, C. Vigouroux, C. Hermans, C. Fayt, P. Veefkind, J.-F. Müller, and M. Van Roozendael
Atmos. Chem. Phys., 15, 12519–12545, https://doi.org/10.5194/acp-15-12519-2015, https://doi.org/10.5194/acp-15-12519-2015, 2015
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We present the new version of the BIRA-IASB algorithm for the retrieval of H2CO columns from OMI and GOME-2A and B measurements. Validation results at seven stations in Europe, China and Africa confirm the capacity of the satellite measurements to resolve diurnal variations in H2CO columns. Furthermore, vertical profiles derived from MAX-DOAS measurements in Beijing and in Bujumbura are used for a more detailed validation exercise. Finally trends are estimated using 10 years of OMI observations.
T. Stavrakou, J.-F. Müller, M. Bauwens, I. De Smedt, M. Van Roozendael, M. De Mazière, C. Vigouroux, F. Hendrick, M. George, C. Clerbaux, P.-F. Coheur, and A. Guenther
Atmos. Chem. Phys., 15, 11861–11884, https://doi.org/10.5194/acp-15-11861-2015, https://doi.org/10.5194/acp-15-11861-2015, 2015
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Formaldehyde columns from two space sensors, GOME-2 and OMI, constrain by inverse modeling the global emissions of HCHO precursors in 2010. The resulting biogenic and pyrogenic fluxes from both optimizations show a very good degree of consistency. The isoprene fluxes are reduced globally by ca. 10%, and emissions from fires decrease by ca. 35%, compared to the prior. Anthropogenic emissions are weakly constrained except over China. Sensitivity inversions show robustness of the inferred fluxes.
M. Coldewey-Egbers, D. G. Loyola, M. Koukouli, D. Balis, J.-C. Lambert, T. Verhoelst, J. Granville, M. van Roozendael, C. Lerot, R. Spurr, S. M. Frith, and C. Zehner
Atmos. Meas. Tech., 8, 3923–3940, https://doi.org/10.5194/amt-8-3923-2015, https://doi.org/10.5194/amt-8-3923-2015, 2015
F. Tack, F. Hendrick, F. Goutail, C. Fayt, A. Merlaud, G. Pinardi, C. Hermans, J.-P. Pommereau, and M. Van Roozendael
Atmos. Meas. Tech., 8, 2417–2435, https://doi.org/10.5194/amt-8-2417-2015, https://doi.org/10.5194/amt-8-2417-2015, 2015
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An algorithm is presented for retrieving tropospheric NO2 vertical column densities from ground-based zenith-sky (ZS) measurements of scattered sunlight. The different steps are fully characterized and recommendations are given for each of them. The retrieval algorithm is applied on a 2-month ZS data set acquired during the CINDI campaign and on a 2-year data set acquired at the OHP NDACC station. The error budget assessment indicates that the overall error on the column values is less than 28%.
A. Keppens, J.-C. Lambert, J. Granville, G. Miles, R. Siddans, J. C. A. van Peet, R. J. van der A, D. Hubert, T. Verhoelst, A. Delcloo, S. Godin-Beekmann, R. Kivi, R. Stübi, and C. Zehner
Atmos. Meas. Tech., 8, 2093–2120, https://doi.org/10.5194/amt-8-2093-2015, https://doi.org/10.5194/amt-8-2093-2015, 2015
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This work thoroughly discusses a methodology, as summarized in a flowchart, for the round-robin evaluation and geophysical validation of nadir ozone profile retrievals and applies the proposed best practice to a pair of optimal-estimation algorithms run on exactly the same level-1 radiance measurements. The quality assessment combines data set content studies, information content studies, and comparisons with ground-based reference measurements.
A. Inness, A.-M. Blechschmidt, I. Bouarar, S. Chabrillat, M. Crepulja, R. J. Engelen, H. Eskes, J. Flemming, A. Gaudel, F. Hendrick, V. Huijnen, L. Jones, J. Kapsomenakis, E. Katragkou, A. Keppens, B. Langerock, M. de Mazière, D. Melas, M. Parrington, V. H. Peuch, M. Razinger, A. Richter, M. G. Schultz, M. Suttie, V. Thouret, M. Vrekoussis, A. Wagner, and C. Zerefos
Atmos. Chem. Phys., 15, 5275–5303, https://doi.org/10.5194/acp-15-5275-2015, https://doi.org/10.5194/acp-15-5275-2015, 2015
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The paper presents results from data assimilation studies with the new Composition-IFS model developed in the MACC project. This system was used in MACC to produce daily analyses and 5-day forecasts of atmospheric composition and is now run daily in the EU’s Copernicus Atmosphere Monitoring Service. The paper looks at the quality of the CO, O3 and NO2 analysis fields obtained with this system, comparing them against observations, a control run and an older version of the model.
B. Franco, F. Hendrick, M. Van Roozendael, J.-F. Müller, T. Stavrakou, E. A. Marais, B. Bovy, W. Bader, C. Fayt, C. Hermans, B. Lejeune, G. Pinardi, C. Servais, and E. Mahieu
Atmos. Meas. Tech., 8, 1733–1756, https://doi.org/10.5194/amt-8-1733-2015, https://doi.org/10.5194/amt-8-1733-2015, 2015
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Formaldehyde (HCHO) amounts are obtained from ground-based Fourier transform infrared solar spectra and UV-visible Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) scans recorded at the Jungfraujoch station (46.5°N, 8.0°E, 3580m a.s.l.). Using HCHO amounts simulated by the chemical transport models GEOS-Chem and IMAGES as intermediates, comparisons reveal that FTIR and MAX-DOAS provide complementary products for the HCHO retrieval.
J. H. G. M. van Geffen, K. F. Boersma, M. Van Roozendael, F. Hendrick, E. Mahieu, I. De Smedt, M. Sneep, and J. P. Veefkind
Atmos. Meas. Tech., 8, 1685–1699, https://doi.org/10.5194/amt-8-1685-2015, https://doi.org/10.5194/amt-8-1685-2015, 2015
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The paper describes improvements to the algorithm for the retrieval of nitrogen dioxide (NO2) concentration from measurements of the Ozone Monitoring Instrument (OMI), launched on board NASA's EOS-Aura satellite in 2004. With these improvements - updates of the wavelength calibration and the reference spectra - the OMI results are consistent with independent NO2 measurements and the overall quality of the spectral fit is improved considerably.
B. Langerock, M. De Mazière, F. Hendrick, C. Vigouroux, F. Desmet, B. Dils, and S. Niemeijer
Geosci. Model Dev., 8, 911–921, https://doi.org/10.5194/gmd-8-911-2015, https://doi.org/10.5194/gmd-8-911-2015, 2015
T. Vlemmix, F. Hendrick, G. Pinardi, I. De Smedt, C. Fayt, C. Hermans, A. Piters, P. Wang, P. Levelt, and M. Van Roozendael
Atmos. Meas. Tech., 8, 941–963, https://doi.org/10.5194/amt-8-941-2015, https://doi.org/10.5194/amt-8-941-2015, 2015
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Two methods are compared to retrieve aerosols, formaldehyde and nitrogen dioxide in the lower troposphere from ground-based remote sensing observations of scattered sunlight in multiple viewing directions. Observations were done in the Beijing area (2008–2011). The two methods show good agreement with respect to the total amount (vertical column) and reasonable agreement with respect to concentrations near the surface and first-order estimates of the vertical profile shape.
S. J. Lawson, P. W. Selleck, I. E. Galbally, M. D. Keywood, M. J. Harvey, C. Lerot, D. Helmig, and Z. Ristovski
Atmos. Chem. Phys., 15, 223–240, https://doi.org/10.5194/acp-15-223-2015, https://doi.org/10.5194/acp-15-223-2015, 2015
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Glyoxal and methylglyoxal are short-lived organic trace gases and important precursors of secondary organic aerosol. Measurements over oceans are sparse. We present the first in situ glyoxal and methylglyoxal observations over remote temperate oceans, alongside observations of precursor gases. Precursor gases cannot explain observed mixing ratios, highlighting an unknown source. We show a large discrepancy between calculated vertical column densities of glyoxal and those retrieved by satellite.
T. Wang, F. Hendrick, P. Wang, G. Tang, K. Clémer, H. Yu, C. Fayt, C. Hermans, C. Gielen, J.-F. Müller, G. Pinardi, N. Theys, H. Brenot, and M. Van Roozendael
Atmos. Chem. Phys., 14, 11149–11164, https://doi.org/10.5194/acp-14-11149-2014, https://doi.org/10.5194/acp-14-11149-2014, 2014
C. Gielen, M. Van Roozendael, F. Hendrick, G. Pinardi, T. Vlemmix, V. De Bock, H. De Backer, C. Fayt, C. Hermans, D. Gillotay, and P. Wang
Atmos. Meas. Tech., 7, 3509–3527, https://doi.org/10.5194/amt-7-3509-2014, https://doi.org/10.5194/amt-7-3509-2014, 2014
M. Pastel, J.-P. Pommereau, F. Goutail, A. Richter, A. Pazmiño, D. Ionov, and T. Portafaix
Atmos. Meas. Tech., 7, 3337–3354, https://doi.org/10.5194/amt-7-3337-2014, https://doi.org/10.5194/amt-7-3337-2014, 2014
N. Hao, M. E. Koukouli, A. Inness, P. Valks, D. G. Loyola, W. Zimmer, D. S. Balis, I. Zyrichidou, M. Van Roozendael, C. Lerot, and R. J. D. Spurr
Atmos. Meas. Tech., 7, 2937–2951, https://doi.org/10.5194/amt-7-2937-2014, https://doi.org/10.5194/amt-7-2937-2014, 2014
F. Carminati, P. Ricaud, J.-P. Pommereau, E. Rivière, S. Khaykin, J.-L. Attié, and J. Warner
Atmos. Chem. Phys., 14, 6195–6211, https://doi.org/10.5194/acp-14-6195-2014, https://doi.org/10.5194/acp-14-6195-2014, 2014
E. W. Chiou, P. K. Bhartia, R. D. McPeters, D. G. Loyola, M. Coldewey-Egbers, V. E. Fioletov, M. Van Roozendael, R. Spurr, C. Lerot, and S. M. Frith
Atmos. Meas. Tech., 7, 1681–1692, https://doi.org/10.5194/amt-7-1681-2014, https://doi.org/10.5194/amt-7-1681-2014, 2014
B. Hassler, I. Petropavlovskikh, J. Staehelin, T. August, P. K. Bhartia, C. Clerbaux, D. Degenstein, M. De Mazière, B. M. Dinelli, A. Dudhia, G. Dufour, S. M. Frith, L. Froidevaux, S. Godin-Beekmann, J. Granville, N. R. P. Harris, K. Hoppel, D. Hubert, Y. Kasai, M. J. Kurylo, E. Kyrölä, J.-C. Lambert, P. F. Levelt, C. T. McElroy, R. D. McPeters, R. Munro, H. Nakajima, A. Parrish, P. Raspollini, E. E. Remsberg, K. H. Rosenlof, A. Rozanov, T. Sano, Y. Sasano, M. Shiotani, H. G. J. Smit, G. Stiller, J. Tamminen, D. W. Tarasick, J. Urban, R. J. van der A, J. P. Veefkind, C. Vigouroux, T. von Clarmann, C. von Savigny, K. A. Walker, M. Weber, J. Wild, and J. M. Zawodny
Atmos. Meas. Tech., 7, 1395–1427, https://doi.org/10.5194/amt-7-1395-2014, https://doi.org/10.5194/amt-7-1395-2014, 2014
H. Brenot, N. Theys, L. Clarisse, J. van Geffen, J. van Gent, M. Van Roozendael, R. van der A, D. Hurtmans, P.-F. Coheur, C. Clerbaux, P. Valks, P. Hedelt, F. Prata, O. Rasson, K. Sievers, and C. Zehner
Nat. Hazards Earth Syst. Sci., 14, 1099–1123, https://doi.org/10.5194/nhess-14-1099-2014, https://doi.org/10.5194/nhess-14-1099-2014, 2014
T. Stavrakou, J.-F. Müller, M. Bauwens, I. De Smedt, M. Van Roozendael, A. Guenther, M. Wild, and X. Xia
Atmos. Chem. Phys., 14, 4587–4605, https://doi.org/10.5194/acp-14-4587-2014, https://doi.org/10.5194/acp-14-4587-2014, 2014
A. Redondas, R. Evans, R. Stuebi, U. Köhler, and M. Weber
Atmos. Chem. Phys., 14, 1635–1648, https://doi.org/10.5194/acp-14-1635-2014, https://doi.org/10.5194/acp-14-1635-2014, 2014
F. Hendrick, J.-F. Müller, K. Clémer, P. Wang, M. De Mazière, C. Fayt, C. Gielen, C. Hermans, J. Z. Ma, G. Pinardi, T. Stavrakou, T. Vlemmix, and M. Van Roozendael
Atmos. Chem. Phys., 14, 765–781, https://doi.org/10.5194/acp-14-765-2014, https://doi.org/10.5194/acp-14-765-2014, 2014
S. M. Khaykin, J.-P. Pommereau, and A. Hauchecorne
Atmos. Chem. Phys., 13, 6391–6402, https://doi.org/10.5194/acp-13-6391-2013, https://doi.org/10.5194/acp-13-6391-2013, 2013
J.-P. Pommereau, F. Goutail, F. Lefèvre, A. Pazmino, C. Adams, V. Dorokhov, P. Eriksen, R. Kivi, K. Stebel, X. Zhao, and M. van Roozendael
Atmos. Chem. Phys., 13, 5299–5308, https://doi.org/10.5194/acp-13-5299-2013, https://doi.org/10.5194/acp-13-5299-2013, 2013
R. A. Stachnik, L. Millán, R. Jarnot, R. Monroe, C. McLinden, S. Kühl, J. Puķīte, M. Shiotani, M. Suzuki, Y. Kasai, F. Goutail, J. P. Pommereau, M. Dorf, and K. Pfeilsticker
Atmos. Chem. Phys., 13, 3307–3319, https://doi.org/10.5194/acp-13-3307-2013, https://doi.org/10.5194/acp-13-3307-2013, 2013
V. Dorokhov, N. Tsvetkova, V. Yushkov, H. Nakajima, G. Ivlev, A. Makshtas, N. Tereb, F. Goutail, A. Pazmino, and J.-P. Pommereau
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amtd-6-2955-2013, https://doi.org/10.5194/amtd-6-2955-2013, 2013
Revised manuscript has not been submitted
Related subject area
Subject: Gases | Technique: Remote Sensing | Topic: Validation and Intercomparisons
Multiscale observations of NH3 around Toronto, Canada
Assessment of the TROPOMI tropospheric NO2 product based on airborne APEX observations
Formaldehyde total column densities over Mexico City: comparison between multi-axis differential optical absorption spectroscopy and solar-absorption Fourier transform infrared measurements
Ground-based validation of the Copernicus Sentinel-5P TROPOMI NO2 measurements with the NDACC ZSL-DOAS, MAX-DOAS and Pandonia global networks
Evaluation of single-footprint AIRS CH4 profile retrieval uncertainties using aircraft profile measurements
Intercomparison of MAX-DOAS vertical profile retrieval algorithms: studies on field data from the CINDI-2 campaign
Validation of SMILES HCl profiles over a wide range from the stratosphere to the lower thermosphere
Comparison of formaldehyde tropospheric columns in Australia and New Zealand using MAX-DOAS, FTIR and TROPOMI
Validation of tropospheric NO2 column measurements of GOME-2A and OMI using MAX-DOAS and direct sun network observations
Evaluating Sentinel-5P TROPOMI tropospheric NO2 column densities with airborne and Pandora spectrometers near New York City and Long Island Sound
Intercomparison and evaluation of ground- and satellite-based stratospheric ozone and temperature profiles above Observatoire de Haute-Provence during the Lidar Validation NDACC Experiment (LAVANDE)
Satellite validation strategy assessments based on the AROMAT campaigns
Intercomparison of TCCON data from two Fourier transform spectrometers at Lauder, New Zealand
A tropopause-related climatological a priori profile for IASI-SOFRID ozone retrievals: improvements and validation
Validation of TROPOMI tropospheric NO2 columns using dual-scan multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements in Uccle, Brussels
Validation of XCO2 and XCH4 retrieved from a portable Fourier transform spectrometer with those from in situ profiles from aircraft-borne instruments
Inter-comparison of MAX-DOAS measurements of tropospheric HONO slant column densities and vertical profiles during the CINDI-2 campaign
Quality controls, bias, and seasonality of CO2 columns in the boreal forest with Orbiting Carbon Observatory-2, Total Carbon Column Observing Network, and EM27/SUN measurements
Intercomparison of Arctic ground-based XH2O observations from COCCON, TCCON and NDACC, and application of COCCON XH2O for IASI and TROPOMI validation
Recovery and validation of Odin/SMR long-term measurements of mesospheric carbon monoxide
1.5 years of TROPOMI CO measurements: comparisons to MOPITT and ATom
The world Brewer reference triad – updated performance assessment and new double triad
Intercomparison of atmospheric CO2 and CH4 abundances on regional scales in boreal areas using Copernicus Atmosphere Monitoring Service (CAMS) analysis, COllaborative Carbon Column Observing Network (COCCON) spectrometers, and Sentinel-5 Precursor satellite observations
In-orbit Earth reflectance validation of TROPOMI on board the Sentinel-5 Precursor satellite
Methane and nitrous oxide from ground-based FTIR at Addis Ababa: observations, error analysis, and comparison with satellite data
On the performance of satellite-based observations of XCO2 in capturing the NOAA Carbon Tracker model and ground-based flask observations over Africa's land mass
Model estimations of geophysical variability between satellite measurements of ozone profiles
TROPOMI–Sentinel-5 Precursor formaldehyde validation using an extensive network of ground-based Fourier-transform infrared stations
Impact of land–water sensitivity contrast on MOPITT retrievals and trends over a coastal city
Verification of the AIRS and MLS ozone algorithms based on retrieved daytime and nighttime ozone
Model-based climatology of diurnal variability in stratospheric ozone as a data analysis tool
Total column water vapour retrieval from S-5P/TROPOMI in the visible blue spectral range
Assessment of NO2 observations during DISCOVER-AQ and KORUS-AQ field campaigns
Intercomparison of NO2, O4, O3 and HCHO slant column measurements by MAX-DOAS and zenith-sky UV–visible spectrometers during CINDI-2
Assessment of the quality of TROPOMI high-spatial-resolution NO2 data products in the Greater Toronto Area
Validation of acetonitrile (CH3CN) measurements in the stratosphere and lower mesosphere from the SMILES instrument on the International Space Station
Comparison of optimal estimation HDO∕H2O retrievals from AIRS with ORACLES measurements
Comparison of GTO-ECV and adjusted MERRA-2 total ozone columns from the last 2 decades and assessment of interannual variability
Shipborne MAX-DOAS measurements for validation of TROPOMI NO2 products
Assessing Measurements of Pollution in the Troposphere (MOPITT) carbon monoxide retrievals over urban versus non-urban regions
Early results and validation of SAGE III-ISS ozone profile measurements from onboard the International Space Station
Validation of MAX-DOAS retrievals of aerosol extinction, SO2, and NO2 through comparison with lidar, sun photometer, active DOAS, and aircraft measurements in the Athabasca oil sands region
Temperature and water vapour measurements in the framework of the Network for the Detection of Atmospheric Composition Change (NDACC)
A reassessment of the discrepancies in the annual variation of δD-H2O in the tropical lower stratosphere between the MIPAS and ACE-FTS satellite data sets
Comparison of TROPOMI/Sentinel-5 Precursor NO2 observations with ground-based measurements in Helsinki
Evaluating the impact of spatial resolution on tropospheric NO2 column comparisons within urban areas using high-resolution airborne data
TCCON and NDACC XCO measurements: difference, discussion and application
Underestimation of column NO2 amounts from the OMI satellite compared to diurnally varying ground-based retrievals from multiple PANDORA spectrometer instruments
Evaluation of MOPITT Version 7 joint TIR–NIR XCO retrievals with TCCON
TROPOMI/S5P total ozone column data: global ground-based validation and consistency with other satellite missions
Shoma Yamanouchi, Camille Viatte, Kimberly Strong, Erik Lutsch, Dylan B. A. Jones, Cathy Clerbaux, Martin Van Damme, Lieven Clarisse, and Pierre-Francois Coheur
Atmos. Meas. Tech., 14, 905–921, https://doi.org/10.5194/amt-14-905-2021, https://doi.org/10.5194/amt-14-905-2021, 2021
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Ammonia (NH3) is a major source of pollution in the air. As such, there have been increasing efforts to measure the atmospheric abundance of NH3 and its spatial and temporal variability. In this study, long-term measurements of NH3 over Toronto, Canada, derived from multiscale datasets are examined. These NH3 datasets were compared to each other and to a model to better understand NH3 variability and to assess model performance.
Frederik Tack, Alexis Merlaud, Marian-Daniel Iordache, Gaia Pinardi, Ermioni Dimitropoulou, Henk Eskes, Bart Bomans, Pepijn Veefkind, and Michel Van Roozendael
Atmos. Meas. Tech., 14, 615–646, https://doi.org/10.5194/amt-14-615-2021, https://doi.org/10.5194/amt-14-615-2021, 2021
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We assess the TROPOMI tropospheric NO2 product (OFFL v1.03.01; 3.5 km × 7 km at nadir observations) based on coinciding airborne APEX reference observations (~75 m × 120 m), acquired over polluted regions in Belgium. The TROPOMI NO2 product meets the mission requirements in terms of precision and accuracy. However, we show that TROPOMI is biased low over polluted areas, mainly due to the limited spatial resolution of a priori input for the AMF computation.
Claudia Rivera Cárdenas, Cesar Guarín, Wolfgang Stremme, Martina M. Friedrich, Alejandro Bezanilla, Diana Rivera Ramos, Cristina A. Mendoza-Rodríguez, Michel Grutter, Thomas Blumenstock, and Frank Hase
Atmos. Meas. Tech., 14, 595–613, https://doi.org/10.5194/amt-14-595-2021, https://doi.org/10.5194/amt-14-595-2021, 2021
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.
Susan S. Kulawik, John R. Worden, Vivienne H. Payne, Dejian Fu, Steven C. Wofsy, Kathryn McKain, Colm Sweeney, Bruce C. Daube Jr., Alan Lipton, Igor Polonsky, Yuguang He, Karen E. Cady-Pereira, Edward J. Dlugokencky, Daniel J. Jacob, and Yi Yin
Atmos. Meas. Tech., 14, 335–354, https://doi.org/10.5194/amt-14-335-2021, https://doi.org/10.5194/amt-14-335-2021, 2021
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This paper shows comparisons of a new single-footprint methane product from the AIRS satellite to aircraft-based observations. We show that this AIRS methane product provides useful information to study seasonal and global methane trends of this important greenhouse gas.
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.
Seidai Nara, Tomohiro O. Sato, Takayoshi Yamada, Tamaki Fujinawa, Kota Kuribayashi, Takeshi Manabe, Lucien Froidevaux, Nathaniel J. Livesey, Kaley A. Walker, Jian Xu, Franz Schreier, Yvan J. Orsolini, Varavut Limpasuvan, Nario Kuno, and Yasuko Kasai
Atmos. Meas. Tech., 13, 6837–6852, https://doi.org/10.5194/amt-13-6837-2020, https://doi.org/10.5194/amt-13-6837-2020, 2020
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In the atmosphere, more than 80 % of chlorine compounds are anthropogenic. Hydrogen chloride (HCl), the main stratospheric chlorine reservoir, is useful to estimate the total budget of the atmospheric chlorine compounds. We report, for the first time, the HCl vertical distribution from the middle troposphere to the lower thermosphere using a high-sensitivity SMILES measurement; the data quality is quantified by comparisons with other measurements and via theoretical error analysis.
Robert G. Ryan, Jeremy D. Silver, Richard Querel, Dan Smale, Steve Rhodes, Matt Tully, Nicholas Jones, and Robyn Schofield
Atmos. Meas. Tech., 13, 6501–6519, https://doi.org/10.5194/amt-13-6501-2020, https://doi.org/10.5194/amt-13-6501-2020, 2020
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Models have identified Australasia as a formaldehyde (HCHO) hotspot from vegetation sources, but few measurement studies exist to verify this. We compare, and find good agreement between, HCHO measurements using three – two ground-based and one satellite-based – different spectroscopic techniques in Australia and New Zealand. This gives confidence in using satellite observations to study HCHO and associated air chemistry and pollution problems in this under-studied part of the world.
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.
Laura M. Judd, Jassim A. Al-Saadi, James J. Szykman, Lukas C. Valin, Scott J. Janz, Matthew G. Kowalewski, Henk J. Eskes, J. Pepijn Veefkind, Alexander Cede, Moritz Mueller, Manuel Gebetsberger, Robert Swap, R. Bradley Pierce, Caroline R. Nowlan, Gonzalo González Abad, Amin Nehrir, and David Williams
Atmos. Meas. Tech., 13, 6113–6140, https://doi.org/10.5194/amt-13-6113-2020, https://doi.org/10.5194/amt-13-6113-2020, 2020
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This paper evaluates Sentinel-5P TROPOMI v1.2 NO2 tropospheric columns over New York City using data from airborne mapping spectrometers and a network of ground-based spectrometers (Pandora) collected in 2018. These evaluations consider impacts due to cloud parameters, a priori profile assumptions, and spatial and temporal variability. Overall, TROPOMI tropospheric NO2 columns appear to have a low bias in this region.
Robin Wing, Wolfgang Steinbrecht, Sophie Godin-Beekmann, Thomas J. McGee, John T. Sullivan, Grant Sumnicht, Gérard Ancellet, Alain Hauchecorne, Sergey Khaykin, and Philippe Keckhut
Atmos. Meas. Tech., 13, 5621–5642, https://doi.org/10.5194/amt-13-5621-2020, https://doi.org/10.5194/amt-13-5621-2020, 2020
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A lidar intercomparison campaign was conducted over a period of 28 nights at Observatoire de Haute-Provence (OHP) in 2017 and 2018. The objective is to validate the ozone and temperature profiles at OHP to ensure the quality of data submitted to the NDACC database remains high. A mobile reference lidar operated by NASA was transported to OHP and operated concurrently with the French lidars. Agreement for ozone was better than 5 % between 20 and 40 km, and temperatures were equal within 3 K.
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.
David F. Pollard, John Robinson, Hisako Shiona, and Dan Smale
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-367, https://doi.org/10.5194/amt-2020-367, 2020
Revised manuscript accepted for AMT
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This work describes the steps taken to ensure a continuous, high quality dataset of column averaged greenhouse gas retrievals from the Total Carbon Column Observing Network (TCCON) site at Lauder, New Zealand, following a change of the Fourier transform spectrometer used to make the measurements from which the retrievals are made.
Brice Barret, Emanuele Emili, and Eric Le Flochmoen
Atmos. Meas. Tech., 13, 5237–5257, https://doi.org/10.5194/amt-13-5237-2020, https://doi.org/10.5194/amt-13-5237-2020, 2020
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The IASI satellite sensor is used to document the variability and evolution of tropospheric ozone (O3). IASI O3 retrievals generally use a single a priori profile which can be responsible for biases and too-low variability. We have therefore implemented a dynamical a priori profile based on pixel location, month and tropopause height. Comparison with 10 years of global ozonesonde profiles shows large improvements in the retrieved tropospheric O3, with biases corrected and enhanced variabilities.
Ermioni Dimitropoulou, François Hendrick, Gaia Pinardi, Martina M. Friedrich, Alexis Merlaud, Frederik Tack, Helene De Longueville, Caroline Fayt, Christian Hermans, Quentin Laffineur, Frans Fierens, and Michel Van Roozendael
Atmos. Meas. Tech., 13, 5165–5191, https://doi.org/10.5194/amt-13-5165-2020, https://doi.org/10.5194/amt-13-5165-2020, 2020
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We present 1 year of dual-scan ground-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements of aerosol and tropospheric NO2 in Uccle (Belgium). Measuring tropospheric NO2 vertical column densities (VCDs) in different azimuthal directions has a positive effect on comparison with measurements from TROPOMI. We prove that the use of inadequate a priori NO2 profile shape data in the TROPOMI retrieval is responsible for the systematic underestimation of S5P NO2 data.
Hirofumi Ohyama, Isamu Morino, Voltaire A. Velazco, Theresa Klausner, Gerry Bagtasa, Matthäus Kiel, Matthias Frey, Akihiro Hori, Osamu Uchino, Tsuneo Matsunaga, Nicholas M. Deutscher, Joshua P. DiGangi, Yonghoon Choi, Glenn S. Diskin, Sally E. Pusede, Alina Fiehn, Anke Roiger, Michael Lichtenstern, Hans Schlager, Pao K. Wang, Charles C.-K. Chou, Maria Dolores Andrés-Hernández, and John P. Burrows
Atmos. Meas. Tech., 13, 5149–5163, https://doi.org/10.5194/amt-13-5149-2020, https://doi.org/10.5194/amt-13-5149-2020, 2020
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Column-averaged dry-air mole fractions of CO2 and CH4 measured by a solar viewing portable Fourier transform spectrometer (EM27/SUN) were validated with in situ profile data obtained during the transfer flights of two aircraft campaigns. Atmospheric dynamical properties based on ERA5 and WRF-Chem were used as criteria for selecting the best aircraft profiles for the validation. The resulting air-mass-independent correction factors for the EM27/SUN data were 0.9878 for CO2 and 0.9829 for CH4.
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
Nicole Jacobs, William R. Simpson, Debra Wunch, Christopher W. O'Dell, Gregory B. Osterman, Frank Hase, Thomas Blumenstock, Qiansi Tu, Matthias Frey, Manvendra K. Dubey, Harrison A. Parker, Rigel Kivi, and Pauli Heikkinen
Atmos. Meas. Tech., 13, 5033–5063, https://doi.org/10.5194/amt-13-5033-2020, https://doi.org/10.5194/amt-13-5033-2020, 2020
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The boreal forest is the largest seasonally varying biospheric CO2-exchange region on Earth. This region is also undergoing amplified climate warming, leading to concerns about the potential for altered regional carbon exchange. Satellite missions, such as the Orbiting Carbon Observatory-2 (OCO-2) project, can measure CO2 abundance over the boreal forest but need validation for the assurance of accuracy. Therefore, we carried out a ground-based validation of OCO-2 CO2 data at three locations.
Qiansi Tu, Frank Hase, Thomas Blumenstock, Matthias Schneider, Andreas Schneider, Rigel Kivi, Pauli Heikkinen, Benjamin Ertl, Christopher Diekmann, Farahnaz Khosrawi, Michael Sommer, Tobias Borsdorff, and Uwe Raffalski
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-378, https://doi.org/10.5194/amt-2020-378, 2020
Revised manuscript accepted for AMT
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We compare column-averaged dry-air mole fractions of water vapor (XH2O) retrievals from COCCON (COllaborative Carbon Column Observing Network) with two co-located ground-based spectrometers as references at two boreal sites. Our study supports the assumption that COCCON also delivers a well-characterized XH2O data product. This is the first published study for applying COCCON for MUSICA IASI and TROPOMI validation.
Francesco Grieco, Kristell Pérot, Donal Murtagh, Patrick Eriksson, Peter Forkman, Bengt Rydberg, Bernd Funke, Kaley A. Walker, and Hugh C. Pumphrey
Atmos. Meas. Tech., 13, 5013–5031, https://doi.org/10.5194/amt-13-5013-2020, https://doi.org/10.5194/amt-13-5013-2020, 2020
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We present a unique – by time extension and geographical coverage – dataset of satellite observations of carbon monoxide (CO) in the mesosphere which will allow us to study dynamical processes, since CO is a very good tracer of circulation in the mesosphere. Previously, the dataset was unusable due to instrumental artefacts that affected the measurements. We identify the cause of the artefacts, eliminate them and prove the quality of the results by comparing with other instrument measurements.
Sara Martínez-Alonso, Merritt Deeter, Helen Worden, Tobias Borsdorff, Ilse Aben, Róisin Commane, Bruce Daube, Gene Francis, Maya George, Jochen Landgraf, Debbie Mao, Kathryn McKain, and Steven Wofsy
Atmos. Meas. Tech., 13, 4841–4864, https://doi.org/10.5194/amt-13-4841-2020, https://doi.org/10.5194/amt-13-4841-2020, 2020
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CO is of great importance in climate and air quality studies. To understand newly available TROPOMI data in the frame of the global CO record, we compared those to satellite (MOPITT) and airborne (ATom) CO datasets. The MOPITT dataset is the longest to date (2000–present) and is well-characterized. We used ATom to validate cloudy TROPOMI data over oceans and investigate TROPOMI's vertical sensitivity to CO. Our results show that TROPOMI CO data are in excellent agreement with the other datasets.
Xiaoyi Zhao, Vitali Fioletov, Michael Brohart, Volodya Savastiouk, Ihab Abboud, Akira Ogyu, Jonathan Davies, Reno Sit, Sum Chi Lee, Alexander Cede, Martin Tiefengraber, Moritz Müller, Debora Griffin, and Chris McLinden
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-324, https://doi.org/10.5194/amt-2020-324, 2020
Revised manuscript accepted for AMT
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The Brewer spectrophotometer is one of the main instruments for measurements of atmospheric total column ozone. The global Brewer network largely relies on the world reference instruments (the Brewer triad) operated by Environment and Climate Change Canada since the early 1980s. This study provides an updated assessment (1999–2019) of the reference instrument performance, in terms of random uncertainties and long-term stability.
Qiansi Tu, Frank Hase, Thomas Blumenstock, Rigel Kivi, Pauli Heikkinen, Mahesh Kumar Sha, Uwe Raffalski, Jochen Landgraf, Alba Lorente, Tobias Borsdorff, Huilin Chen, Florian Dietrich, and Jia Chen
Atmos. Meas. Tech., 13, 4751–4771, https://doi.org/10.5194/amt-13-4751-2020, https://doi.org/10.5194/amt-13-4751-2020, 2020
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Two COCCON instruments are used to observe multiyear greenhouse gases in boreal areas and are compared with the CAMS analysis and S5P satellite data. These three datasets predict greenhouse gas gradients with reasonable agreement. The results indicate that the COCCON instrument has the capability of measuring gradients on regional scales, and observations performed with the portable spectrometers can contribute to inferring sources and sinks and to validating spaceborne greenhouse gases.
Lieuwe G. Tilstra, Martin de Graaf, Ping Wang, and Piet Stammes
Atmos. Meas. Tech., 13, 4479–4497, https://doi.org/10.5194/amt-13-4479-2020, https://doi.org/10.5194/amt-13-4479-2020, 2020
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The goal of the study was to determine the accuracy of the radiometric calibration of the TROPOMI instrument on board the Sentinel-5 Precursor satellite in flight. The Earth reflectances were compared to radiative transfer calculations. We report calibration accuracies and errors for 21 selected wavelength bands between 328 and 2314 nm, located in TROPOMI spectral bands 3–7. The reported numbers can be used to perform corrections that will benefit the retrievals of many atmospheric properties.
Temesgen Yirdaw Berhe, Gizaw Mengistu Tsidu, Thomas Blumenstock, Frank Hase, and Gabriele P. Stiller
Atmos. Meas. Tech., 13, 4079–4096, https://doi.org/10.5194/amt-13-4079-2020, https://doi.org/10.5194/amt-13-4079-2020, 2020
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The retrieved CH4 and N2O VMR and column amounts from Addis Ababa, tropical site, are found to exhibit very good agreement with all coincident satellite observations (MIPAS, MLS, and AIRS). Furthermore, the bias obtained from the comparison is comparable to the precision of FTIR measurement, which allows the use of data in further scientific studies as it represents a unique environment of tropical Africa, a region poorly investigated in the past.
Anteneh Getachew Mengistu and Gizaw Mengistu Tsidu
Atmos. Meas. Tech., 13, 4009–4033, https://doi.org/10.5194/amt-13-4009-2020, https://doi.org/10.5194/amt-13-4009-2020, 2020
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This paper assesses the performance of observed XCO2 from the GOSAT and OCO-2 satellites in capturing simulated XCO2 from the NOAA Carbon Tracker model over Africa. These satellite observations and Carbon Tracker mixing ratios near the surface are also compared to available in situ CO2 flask data from Assekrem, Algeria; Mt. Kenya; Gobabeb, Namibia; and Cape Town; as well as to data off the coast at Seychelles, Ascension Island, and at Izana, Tenerife.
Patrick E. Sheese, Kaley A. Walker, Chris D. Boone, Doug A. Degenstein, Felicia Kolonjari, David Plummer, Douglas E. Kinnison, Patrick Jöckel, and Thomas von Clarmann
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-207, https://doi.org/10.5194/amt-2020-207, 2020
Revised manuscript accepted for AMT
Corinne Vigouroux, Bavo Langerock, Carlos Augusto Bauer Aquino, Thomas Blumenstock, Zhibin Cheng, Martine De Mazière, Isabelle De Smedt, Michel Grutter, James W. Hannigan, Nicholas Jones, Rigel Kivi, Diego Loyola, Erik Lutsch, Emmanuel Mahieu, Maria Makarova, Jean-Marc Metzger, Isamu Morino, Isao Murata, Tomoo Nagahama, Justus Notholt, Ivan Ortega, Mathias Palm, Gaia Pinardi, Amelie Röhling, Dan Smale, Wolfgang Stremme, Kim Strong, Ralf Sussmann, Yao Té, Michel van Roozendael, Pucai Wang, and Holger Winkler
Atmos. Meas. Tech., 13, 3751–3767, https://doi.org/10.5194/amt-13-3751-2020, https://doi.org/10.5194/amt-13-3751-2020, 2020
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We validate the TROPOMI HCHO product with ground-based FTIR (Fourier-transform infrared) measurements from 25 stations. We find that TROPOMI overestimates HCHO under clean conditions, while it underestimates it at high HCHO levels. Both TROPOMI precision and accuracy reach the pre-launch requirements, and its precision can even be 2 times better. The observed TROPOMI seasonal variability is in agreement with the FTIR data. The TROPOMI random uncertainty and data filtering should be refined.
Ian Ashpole and Aldona Wiacek
Atmos. Meas. Tech., 13, 3521–3542, https://doi.org/10.5194/amt-13-3521-2020, https://doi.org/10.5194/amt-13-3521-2020, 2020
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We analyse temporal trends in carbon monoxide (CO) detected by the MOPITT satellite instrument over the coastal city of Halifax, Canada. We show that trends in surface level CO differ significantly depending on the data product used (Level 2 or Level 3). This is linked to the different sensitivity with which MOPITT can detect CO at the surface over land and water as well as the differing degree to which the data can be filtered to account for this in the different products.
Wannan Wang, Tianhai Cheng, Ronald van der A, Jos de Laat, and Jason E. Williams
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-194, https://doi.org/10.5194/amt-2020-194, 2020
Revised manuscript accepted for AMT
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The scope of the paper is the evaluation of the AIRS and MLS ozone algorithms via comparison with daytime and nighttime ozone datasets. Results show further refinements of AIRS ozone algorithm for better surface emissivity retrievals are required and cloud covers is another problem that needs to be solved. An inconsistency is found in the ‘AscDescMode’ flag of MLS v4.20 standard O3 product in 90° S–60° S and 60° N–90° N, resulting in inconsistent ozone profiles in these regions before May 2015.
Stacey M. Frith, Pawan K. Bhartia, Luke D. Oman, Natalya A. Kramarova, Richard D. McPeters, and Gordon J. Labow
Atmos. Meas. Tech., 13, 2733–2749, https://doi.org/10.5194/amt-13-2733-2020, https://doi.org/10.5194/amt-13-2733-2020, 2020
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We use the NASA GEOS-GMI chemistry climate model to construct a climatology of stratospheric ozone diurnal variations as a function of latitude, pressure and month, which can be used in a variety of data analysis tasks involving ozone observations made at different times of the day. The climatology compares well with previous modeling simulations and available observations, and to the authors' knowledge is the first characterization of the diurnal cycle available for general ozone data analyses.
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 %.
Sungyeon Choi, Lok N. Lamsal, Melanie Follette-Cook, Joanna Joiner, Nickolay A. Krotkov, William H. Swartz, Kenneth E. Pickering, Christopher P. Loughner, Wyat Appel, Gabriele Pfister, Pablo E. Saide, Ronald C. Cohen, Andrew J. Weinheimer, and Jay R. Herman
Atmos. Meas. Tech., 13, 2523–2546, https://doi.org/10.5194/amt-13-2523-2020, https://doi.org/10.5194/amt-13-2523-2020, 2020
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.
Xiaoyi Zhao, Debora Griffin, Vitali Fioletov, Chris McLinden, Alexander Cede, Martin Tiefengraber, Moritz Müller, Kristof Bognar, Kimberly Strong, Folkert Boersma, Henk Eskes, Jonathan Davies, Akira Ogyu, and Sum Chi Lee
Atmos. Meas. Tech., 13, 2131–2159, https://doi.org/10.5194/amt-13-2131-2020, https://doi.org/10.5194/amt-13-2131-2020, 2020
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Pandora NO2 measurements made at three sites located in the Toronto area are used to evaluate the TROPOspheric Monitoring Instrument (TROPOMI) NO2 data products, including standard NO2 and research data developed using a high-resolution regional air quality forecast model. TROPOMI pixels located upwind and downwind from the Pandora sites were analyzed by a new wind-based validation method, which revealed the spatial patterns of local and transported emissions and regional air quality changes.
Tamaki Fujinawa, Tomohiro O. Sato, Takayoshi Yamada, Seidai Nara, Yuki Uchiyama, Kodai Takahashi, Naohiro Yoshida, and Yasuko Kasai
Atmos. Meas. Tech., 13, 2119–2129, https://doi.org/10.5194/amt-13-2119-2020, https://doi.org/10.5194/amt-13-2119-2020, 2020
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We performed an error analysis of SMILES observations for acetonitrile and a validation using the MLS observations by extracting the coincident points between SMILES and MLS data. The major error sources for the SMILES observations were quantitatively estimated. At upper pressure levels the difference between the two datasets increased because of an uncertainty in MLS observations. The results showed that SMILES has an advantage in measuring acetonitrile in the upper stratosphere and mesosphere.
Robert L. Herman, John Worden, David Noone, Dean Henze, Kevin Bowman, Karen Cady-Pereira, Vivienne H. Payne, Susan S. Kulawik, and Dejian Fu
Atmos. Meas. Tech., 13, 1825–1834, https://doi.org/10.5194/amt-13-1825-2020, https://doi.org/10.5194/amt-13-1825-2020, 2020
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This study is the first assessment and validation of AIRS HDO / H2O retrieved by optimal estimation. Initial comparisons with in situ measurements from NASA ORACLES are promising: the small bias and consistent rms of AIRS suggest that AIRS has well-characterized HDO / H2O. This analysis opens the possibility of a new 17-year long-term data record of global tropospheric HDO / H2O measured from space.
Melanie Coldewey-Egbers, Diego G. Loyola, Gordon Labow, and Stacey M. Frith
Atmos. Meas. Tech., 13, 1633–1654, https://doi.org/10.5194/amt-13-1633-2020, https://doi.org/10.5194/amt-13-1633-2020, 2020
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We compare total ozone columns from the satellite-based GOME-type Total Ozone Essential Climate Variable record and the adjusted Modern Era Retrospective Analysis for Research and Applications version 2 reanalysis during their overlap period from 1995 to 2018. Ozone columns and anomalies show a very good agreement in terms of spatial and temporal patterns. In the tropics the interannual variability is assessed by means of an EOF analysis and both data records show a remarkable consistency.
Ping Wang, Ankie Piters, Jos van Geffen, Olaf Tuinder, Piet Stammes, and Stefan Kinne
Atmos. Meas. Tech., 13, 1413–1426, https://doi.org/10.5194/amt-13-1413-2020, https://doi.org/10.5194/amt-13-1413-2020, 2020
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The comparison of shipborne MAX-DOAS and TROPOMI NO2 products is important for the evaluation of the TROPOMI products. The ship cruises were mainly over remote oceans, thus we only measured background tropospheric NO2. Stratospheric NO2 was measured more accurately because there was almost no contamination from tropospheric NO2. We found that the TROPOMI stratospheric NO2 vertical column densities were slightly higher than the MAX-DOAS measurements.
Wenfu Tang, Helen M. Worden, Merritt N. Deeter, David P. Edwards, Louisa K. Emmons, Sara Martínez-Alonso, Benjamin Gaubert, Rebecca R. Buchholz, Glenn S. Diskin, Russell R. Dickerson, Xinrong Ren, Hao He, and Yutaka Kondo
Atmos. Meas. Tech., 13, 1337–1356, https://doi.org/10.5194/amt-13-1337-2020, https://doi.org/10.5194/amt-13-1337-2020, 2020
M. Patrick McCormick, Liqiao Lei, Michael T. Hill, John Anderson, Richard Querel, and Wolfgang Steinbrecht
Atmos. Meas. Tech., 13, 1287–1297, https://doi.org/10.5194/amt-13-1287-2020, https://doi.org/10.5194/amt-13-1287-2020, 2020
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We present a validation of O3 data from the SAGE III-ISS instrument using ground-based lidars and ozonesondes from Hohenpeißenberg and Lauder as well as O3 data from the ACE-FTS instrument. Average differences in the O3 concentration between SAGE III-ISS and the lidar and sonde observations are < 10 % over much of the lower and middle stratosphere. The ACE comparisons are < 5 % from 20 to 45 km. These results provide confidence in the SAGE III measurements of global stratospheric O3 profiles.
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.
Benedetto De Rosa, Paolo Di Girolamo, and Donato Summa
Atmos. Meas. Tech., 13, 405–427, https://doi.org/10.5194/amt-13-405-2020, https://doi.org/10.5194/amt-13-405-2020, 2020
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Temperature and water vapour profiles measured by the BASIL lidar are compared with profiles from several sensors/models, namely radiosondes, the IASI and AIRS satellite sensors and model reanalyses data (ECMWF & ECMWF-ERA). The comparison effort allows for the performance of all of the sensors and models to be assessed in terms of bias and RMS deviation. BASIL measurement quality is confirmed to be high enough for long-term monitoring of atmospheric composition and thermal structure changes.
Stefan Lossow, Charlotta Högberg, Farahnaz Khosrawi, Gabriele P. Stiller, Ralf Bauer, Kaley A. Walker, Sylvia Kellmann, Andrea Linden, Michael Kiefer, Norbert Glatthor, Thomas von Clarmann, Donal P. Murtagh, Jörg Steinwagner, Thomas Röckmann, and Roland Eichinger
Atmos. Meas. Tech., 13, 287–308, https://doi.org/10.5194/amt-13-287-2020, https://doi.org/10.5194/amt-13-287-2020, 2020
Iolanda Ialongo, Henrik Virta, Henk Eskes, Jari Hovila, and John Douros
Atmos. Meas. Tech., 13, 205–218, https://doi.org/10.5194/amt-13-205-2020, https://doi.org/10.5194/amt-13-205-2020, 2020
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New satellite-based nitrogen dioxide (NO2) data from TROPOMI/Sentinel 5P are used to monitor air pollution levels at the urban site of Helsinki, Finland. NO2 is a polluting gas produced by fossil fuel combustion. TROPOMI NO2 data agree with ground-based reference measurements within 10 % and show similar day-to-day and weekly variability. The results confirm that satellite-based observations can bring additional information to traditional in situ measurements for urban air quality monitoring.
Laura M. Judd, Jassim A. Al-Saadi, Scott J. Janz, Matthew G. Kowalewski, R. Bradley Pierce, James J. Szykman, Lukas C. Valin, Robert Swap, Alexander Cede, Moritz Mueller, Martin Tiefengraber, Nader Abuhassan, and David Williams
Atmos. Meas. Tech., 12, 6091–6111, https://doi.org/10.5194/amt-12-6091-2019, https://doi.org/10.5194/amt-12-6091-2019, 2019
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In 2017, an airborne mapping spectrometer (GeoTASO) was used to observe high-resolution column densities of nitrogen dioxide (NO2) over the western shore of Lake Michigan and the Los Angeles Basin. These data were used to simulate the spatial resolution of current and future satellite NO2 retrievals to evaluate the impact of pixel size on comparisons to ground-based observations in urban areas. As spatial resolution improves, the sensitivity to more heterogeneously polluted scenes increases.
Minqiang Zhou, Bavo Langerock, Corinne Vigouroux, Mahesh Kumar Sha, Christian Hermans, Jean-Marc Metzger, Huilin Chen, Michel Ramonet, Rigel Kivi, Pauli Heikkinen, Dan Smale, David F. Pollard, Nicholas Jones, Voltaire A. Velazco, Omaira E. García, Matthias Schneider, Mathias Palm, Thorsten Warneke, and Martine De Mazière
Atmos. Meas. Tech., 12, 5979–5995, https://doi.org/10.5194/amt-12-5979-2019, https://doi.org/10.5194/amt-12-5979-2019, 2019
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The differences between the TCCON and NDACC XCO measurements are investigated and discussed based on six NDACC–TCCON sites (Ny-Ålesund, Bremen, Izaña, Saint-Denis, Wollongong and Lauder) using data over the period 2007–2017. The smoothing errors from both TCCON and NDACC measurements are estimated. In addition, the scaling factor of the TCCON XCO data is reassessed by comparing with the AirCore measurements at Sodankylä and Orléans.
Jay Herman, Nader Abuhassan, Jhoon Kim, Jae Kim, Manvendra Dubey, Marcelo Raponi, and Maria Tzortziou
Atmos. Meas. Tech., 12, 5593–5612, https://doi.org/10.5194/amt-12-5593-2019, https://doi.org/10.5194/amt-12-5593-2019, 2019
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Total column NO2 (TCNO2) from the Ozone Measuring Instrument (OMI) is compared for 14 sites with ground-based PANDORA spectrometer instruments making direct-sun measurements. These sites have high TCNO2, causing significant air quality problems that can affect human health. OMI almost always underestimates the amount of TCNO2 by 50 to 100 %. OMI's large field of view (FOV) is the most likely factor when comparing OMI TCNO2 to retrievals with PANDORA. OMI misses higher afternoon values of TCNO2.
Jacob K. Hedelius, Tai-Long He, Dylan B. A. Jones, Bianca C. Baier, Rebecca R. Buchholz, Martine De Mazière, Nicholas M. Deutscher, Manvendra K. Dubey, Dietrich G. Feist, David W. T. Griffith, Frank Hase, Laura T. Iraci, Pascal Jeseck, Matthäus Kiel, Rigel Kivi, Cheng Liu, Isamu Morino, Justus Notholt, Young-Suk Oh, Hirofumi Ohyama, David F. Pollard, Markus Rettinger, Sébastien Roche, Coleen M. Roehl, Matthias Schneider, Kei Shiomi, Kimberly Strong, Ralf Sussmann, Colm Sweeney, Yao Té, Osamu Uchino, Voltaire A. Velazco, Wei Wang, Thorsten Warneke, Paul O. Wennberg, Helen M. Worden, and Debra Wunch
Atmos. Meas. Tech., 12, 5547–5572, https://doi.org/10.5194/amt-12-5547-2019, https://doi.org/10.5194/amt-12-5547-2019, 2019
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We seek ways to improve the accuracy of column measurements of carbon monoxide (CO) – an important tracer of pollution – made from the MOPITT satellite instrument. We devise a filtering scheme which reduces the scatter and also eliminates bias among the MOPITT detectors. Compared to ground-based observations, MOPITT measurements are about 6 %–8 % higher. When MOPITT data are implemented in a global assimilation model, they tend to reduce the model mismatch with aircraft measurements.
Katerina Garane, Maria-Elissavet Koukouli, Tijl Verhoelst, Christophe Lerot, Klaus-Peter Heue, Vitali Fioletov, Dimitrios Balis, Alkiviadis Bais, Ariane Bazureau, Angelika Dehn, Florence Goutail, Jose Granville, Debora Griffin, Daan Hubert, Arno Keppens, Jean-Christopher Lambert, Diego Loyola, Chris McLinden, Andrea Pazmino, Jean-Pierre Pommereau, Alberto Redondas, Fabian Romahn, Pieter Valks, Michel Van Roozendael, Jian Xu, Claus Zehner, Christos Zerefos, and Walter Zimmer
Atmos. Meas. Tech., 12, 5263–5287, https://doi.org/10.5194/amt-12-5263-2019, https://doi.org/10.5194/amt-12-5263-2019, 2019
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The Sentinel-5 Precursor TROPOMI near real time (NRTI) and offline (OFFL) total ozone column (TOC) products are validated against direct-sun and twilight zenith-sky ground-based TOC measurements and other already known spaceborne sensors. The results show that the TROPOMI TOC measurements are in very good agreement with the ground-based measurements and satellite sensor measurements and that they are well within the product requirements.
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Special issue
Short summary
Comparisons between satellite and ground-based measurements of the
atmosphere are inevitably affected by natural variability due to
mismatches in spatial and temporal co-location. These
additional terms in the comparison error budget are quantified here
for total ozone column comparisons using an Observing System Simulation
Experiment. Even when using tight co-location criteria, atmospheric
variability is found to impact the comparisons significantly.
Comparisons between satellite and ground-based measurements of the
atmosphere are inevitably...
