Articles | Volume 6, issue 2
https://doi.org/10.5194/amt-6-371-2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Special issue:
https://doi.org/10.5194/amt-6-371-2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
18 Feb 2013
Research article |
| 18 Feb 2013
Characterisation of GOME-2 formaldehyde retrieval sensitivity
W. Hewson
EOS Group, Department of Physics and Astronomy, University of Leicester, Leicester, UK
H. Bösch
EOS Group, Department of Physics and Astronomy, University of Leicester, Leicester, UK
M. P. Barkley
EOS Group, Department of Physics and Astronomy, University of Leicester, Leicester, UK
I. De Smedt
Belgian Institute for Space Aeronomy (BIRA-IASB), Avenue Circulaire, 3, 1180, Brussels, Belgium
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Yuhang Zhang, Huan Yu, Isabelle De Smedt, Jintai Lin, Nicolas Theys, Michel Van Roozendael, Gaia Pinardi, Steven Compernolle, Ruijing Ni, Fangxuan Ren, Sijie Wang, Lulu Chen, Jos Van Geffen, Mengyao Liu, Alexander M. Cede, Martin Tiefengraber, Alexis Merlaud, Martina M. Friedrich, Andreas Richter, Ankie Piters, Vinod Kumar, Vinayak Sinha, Thomas Wagner, Yongjoo Choi, Hisahiro Takashima, Yugo Kanaya, Hitoshi Irie, Robert Spurr, Wenfu Sun, and Lorenzo Fabris
Atmos. Meas. Tech., 18, 1561–1589, https://doi.org/10.5194/amt-18-1561-2025, https://doi.org/10.5194/amt-18-1561-2025, 2025
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We developed an advanced algorithm for global retrieval of TROPOspheric Monitoring Instrument (TROPOMI) HCHO and NO2 vertical column densities with much improved consistency. Sensitivity tests demonstrate the complexity and nonlinear interactions of auxiliary parameters in the air mass factor calculation. An improved agreement is found with measurements from a global ground-based instrument network. The scientific retrieval provides a useful source of information for studies combining HCHO and NO2.
Beata Opacka, Trissevgeni Stavrakou, Jean-François Müller, Isabelle De Smedt, Jos van Geffen, Eloise A. Marais, Rebekah P. Horner, Dylan B. Millet, Kelly C. Wells, and Alex B. Guenther
Atmos. Chem. Phys., 25, 2863–2894, https://doi.org/10.5194/acp-25-2863-2025, https://doi.org/10.5194/acp-25-2863-2025, 2025
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Vegetation releases biogenic volatile organic compounds, while soils and lightning contribute to the natural emissions of nitrogen oxides into the atmosphere. These gases interact in complex ways. Using satellite data and models, we developed a new method to simultaneously optimize these natural emissions over Africa in 2019. Our approach resulted in an increase in natural emissions, supported by independent data indicating that current estimates are underestimated.
Huan Yu, Isabelle De Smedt, Nicolas Theys, Maarten Sneep, Pepijn Veefkind, and Michel Van Roozendael
EGUsphere, https://doi.org/10.5194/egusphere-2025-478, https://doi.org/10.5194/egusphere-2025-478, 2025
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
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We introduce a new cloud retrieval algorithm using the O2-O2 absorption band at 477 nm to generate harmonized cloud datasets from OMI and TROPOMI. The algorithm improves upon the OMI O2-O2 operational cloud algorithm in several aspects. The new approach improves consistency in cloud parameters and NO2 retrievals between two sensors.
Min Huang, Gregory R. Carmichael, Kevin W. Bowman, Isabelle De Smedt, Andreas Colliander, Michael H. Cosh, Sujay V. Kumar, Alex B. Guenther, Scott J. Janz, Ryan M. Stauffer, Anne M. Thompson, Niko M. Fedkin, Robert J. Swap, John D. Bolten, and Alicia T. Joseph
Atmos. Chem. Phys., 25, 1449–1476, https://doi.org/10.5194/acp-25-1449-2025, https://doi.org/10.5194/acp-25-1449-2025, 2025
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We use model simulations along with multiplatform, multidisciplinary observations and a range of analysis methods to estimate and understand the distributions, temporal changes, and impacts of reactive nitrogen and ozone over the most populous US region that has undergone significant environmental changes. Deposition, biogenic emissions, and extra-regional sources have been playing increasingly important roles in controlling pollutant budgets in this area as local anthropogenic emissions drop.
Jin Liao, Glenn M. Wolfe, Alexander E. Kotsakis, Julie M. Nicely, Jason M. St. Clair, Thomas F. Hanisco, Gonzalo González Abad, Caroline R. Nowlan, Zolal Ayazpour, Isabelle De Smedt, Eric C. Apel, and Rebecca S. Hornbrook
Atmos. Meas. Tech., 18, 1–16, https://doi.org/10.5194/amt-18-1-2025, https://doi.org/10.5194/amt-18-1-2025, 2025
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Validation of satellite HCHO over the remote marine regions is relatively low, and modeled HCHO in these regions is usually added as a global satellite HCHO background. This paper intercompares three satellite HCHO retrievals and validates them against in situ observations from the NASA ATom mission. All retrievals are correlated with ATom-integrated columns over remote oceans, with OMI SAO (v004) showing the best agreement. A persistent low bias is found in all retrievals at high latitudes.
Eunjo S. Ha, Rokjin J. Park, Hyeong-Ahn Kwon, Gitaek T. Lee, Sieun D. Lee, Seunga Shin, Dong-Won Lee, Hyunkee Hong, Christophe Lerot, Isabelle De Smedt, Thomas Danckaert, Francois Hendrick, and Hitoshi Irie
Atmos. Meas. Tech., 17, 6369–6384, https://doi.org/10.5194/amt-17-6369-2024, https://doi.org/10.5194/amt-17-6369-2024, 2024
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In this study, we evaluated the GEMS glyoxal products by comparing them with TROPOMI and MAX-DOAS measurements. GEMS and TROPOMI VCDs present similar spatial distributions. Monthly variations in GEMS VCDs and TROPOMI and MAX-DOAS VCDs differ in northeastern Asia, which we attributed to a polluted reference spectrum and high NO2 concentrations. GEMS glyoxal products with unparalleled temporal resolution would enrich our understanding of VOC emissions and diurnal variation.
Yasin Elshorbany, Jerald R. Ziemke, Sarah Strode, Hervé Petetin, Kazuyuki Miyazaki, Isabelle De Smedt, Kenneth Pickering, Rodrigo J. Seguel, Helen Worden, Tamara Emmerichs, Domenico Taraborrelli, Maria Cazorla, Suvarna Fadnavis, Rebecca R. Buchholz, Benjamin Gaubert, Néstor Y. Rojas, Thiago Nogueira, Thérèse Salameh, and Min Huang
Atmos. Chem. Phys., 24, 12225–12257, https://doi.org/10.5194/acp-24-12225-2024, https://doi.org/10.5194/acp-24-12225-2024, 2024
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We investigated tropospheric ozone spatial variability and trends from 2005 to 2019 and related those to ozone precursors on global and regional scales. We also investigate the spatiotemporal characteristics of the ozone formation regime in relation to ozone chemical sources and sinks. Our analysis is based on remote sensing products of the tropospheric column of ozone and its precursors, nitrogen dioxide, formaldehyde, and total column CO, as well as ozonesonde data and model simulations.
Suvarna Fadnavis, Yasin Elshorbany, Jerald Ziemke, Brice Barret, Alexandru Rap, P. R. Satheesh Chandran, Richard Pope, Vijay Sagar, Domenico Taraborrelli, Eric Le Flochmoen, Juan Cuesta, Catherine Wespes, Folkert Boersma, Isolde Glissenaar, Isabelle De Smedt, Michel Van Roozendael, Hervé Petetin, and Isidora Anglou
EGUsphere, https://doi.org/10.5194/egusphere-2024-3050, https://doi.org/10.5194/egusphere-2024-3050, 2024
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Satellites and model simulations show enhancement in tropospheric ozone, which is highly impacted by human-produced Nitrous oxides compared to volatile organic compounds. The increased amount of ozone enhances ozone radiative forcing. The ozone enhancement and associated radiative forcing are highest over South and East Asia. The emissions of Nitrous oxides show a higher influence in shifting ozone photochemical regimes than volatile organic compounds.
Gitaek T. Lee, Rokjin J. Park, Hyeong-Ahn Kwon, Eunjo S. Ha, Sieun D. Lee, Seunga Shin, Myoung-Hwan Ahn, Mina Kang, Yong-Sang Choi, Gyuyeon Kim, Dong-Won Lee, Deok-Rae Kim, Hyunkee Hong, Bavo Langerock, Corinne Vigouroux, Christophe Lerot, Francois Hendrick, Gaia Pinardi, Isabelle De Smedt, Michel Van Roozendael, Pucai Wang, Heesung Chong, Yeseul Cho, and Jhoon Kim
Atmos. Chem. Phys., 24, 4733–4749, https://doi.org/10.5194/acp-24-4733-2024, https://doi.org/10.5194/acp-24-4733-2024, 2024
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This study evaluates the Geostationary Environment Monitoring Spectrometer (GEMS) HCHO product by comparing its vertical column densities (VCDs) with those of TROPOMI and ground-based observations. Based on some sensitivity tests, obtaining radiance references under clear-sky conditions significantly improves HCHO retrieval quality. GEMS HCHO VCDs captured seasonal and diurnal variations well during the first year of observation, showing consistency with TROPOMI and ground-based observations.
Jean-François Müller, Trissevgeni Stavrakou, Glenn-Michael Oomen, Beata Opacka, Isabelle De Smedt, Alex Guenther, Corinne Vigouroux, Bavo Langerock, Carlos Augusto Bauer Aquino, Michel Grutter, James Hannigan, Frank Hase, Rigel Kivi, Erik Lutsch, Emmanuel Mahieu, Maria Makarova, Jean-Marc Metzger, Isamu Morino, Isao Murata, Tomoo Nagahama, Justus Notholt, Ivan Ortega, Mathias Palm, Amelie Röhling, Wolfgang Stremme, Kimberly Strong, Ralf Sussmann, Yao Té, and Alan Fried
Atmos. Chem. Phys., 24, 2207–2237, https://doi.org/10.5194/acp-24-2207-2024, https://doi.org/10.5194/acp-24-2207-2024, 2024
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Formaldehyde observations from satellites can be used to constrain the emissions of volatile organic compounds, but those observations have biases. Using an atmospheric model, aircraft and ground-based remote sensing data, we quantify these biases, propose a correction to the data, and assess the consequence of this correction for the evaluation of emissions.
Glenn-Michael Oomen, Jean-François Müller, Trissevgeni Stavrakou, Isabelle De Smedt, Thomas Blumenstock, Rigel Kivi, Maria Makarova, Mathias Palm, Amelie Röhling, Yao Té, Corinne Vigouroux, Martina M. Friedrich, Udo Frieß, François Hendrick, Alexis Merlaud, Ankie Piters, Andreas Richter, Michel Van Roozendael, and Thomas Wagner
Atmos. Chem. Phys., 24, 449–474, https://doi.org/10.5194/acp-24-449-2024, https://doi.org/10.5194/acp-24-449-2024, 2024
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Natural emissions from vegetation have a profound impact on air quality for their role in the formation of harmful tropospheric ozone and organic aerosols, yet these emissions are highly uncertain. In this study, we quantify emissions of organic gases over Europe using high-quality satellite measurements of formaldehyde. These satellite observations suggest that emissions from vegetation are much higher than predicted by models, especially in southern Europe.
Rodriguez Yombo Phaka, Alexis Merlaud, Gaia Pinardi, Martina M. Friedrich, Michel Van Roozendael, Jean-François Müller, Trissevgeni Stavrakou, Isabelle De Smedt, François Hendrick, Ermioni Dimitropoulou, Richard Bopili Mbotia Lepiba, Edmond Phuku Phuati, Buenimio Lomami Djibi, Lars Jacobs, Caroline Fayt, Jean-Pierre Mbungu Tsumbu, and Emmanuel Mahieu
Atmos. Meas. Tech., 16, 5029–5050, https://doi.org/10.5194/amt-16-5029-2023, https://doi.org/10.5194/amt-16-5029-2023, 2023
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We present air quality measurements in Kinshasa, Democratic Republic of the Congo, performed with a newly developed instrument which was installed on a roof of the University of Kinshasa in November 2019. The instrument records spectra of the scattered sunlight, from which we derive the abundances of nitrogen dioxide and formaldehyde, two important pollutants. We compare our ground-based measurements with those of the TROPOspheric Monitoring Instrument (TROPOMI).
Robert J. Parker, Chris Wilson, Edward Comyn-Platt, Garry Hayman, Toby R. Marthews, A. Anthony Bloom, Mark F. Lunt, Nicola Gedney, Simon J. Dadson, Joe McNorton, Neil Humpage, Hartmut Boesch, Martyn P. Chipperfield, Paul I. Palmer, and Dai Yamazaki
Biogeosciences, 19, 5779–5805, https://doi.org/10.5194/bg-19-5779-2022, https://doi.org/10.5194/bg-19-5779-2022, 2022
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Wetlands are the largest natural source of methane, one of the most important climate gases. The JULES land surface model simulates these emissions. We use satellite data to evaluate how well JULES reproduces the methane seasonal cycle over different tropical wetlands. It performs well for most regions; however, it struggles for some African wetlands influenced heavily by river flooding. We explain the reasons for these deficiencies and highlight how future development will improve these areas.
Nicolas Theys, Christophe Lerot, Hugues Brenot, Jeroen van Gent, Isabelle De Smedt, Lieven Clarisse, Mike Burton, Matthew Varnam, Catherine Hayer, Benjamin Esse, and Michel Van Roozendael
Atmos. Meas. Tech., 15, 4801–4817, https://doi.org/10.5194/amt-15-4801-2022, https://doi.org/10.5194/amt-15-4801-2022, 2022
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Sulfur dioxide plume height after a volcanic eruption is an important piece of information for many different scientific studies and applications. Satellite UV retrievals are useful in this respect, but available algorithms have shown so far limited sensitivity to SO2 height. Here we present a new technique to improve the retrieval of SO2 plume height for SO2 columns as low as 5 DU. We demonstrate the algorithm using TROPOMI measurements and compare with other height estimates.
Pieternel F. Levelt, Deborah C. Stein Zweers, Ilse Aben, Maite Bauwens, Tobias Borsdorff, Isabelle De Smedt, Henk J. Eskes, Christophe Lerot, Diego G. Loyola, Fabian Romahn, Trissevgeni Stavrakou, Nicolas Theys, Michel Van Roozendael, J. Pepijn Veefkind, and Tijl Verhoelst
Atmos. Chem. Phys., 22, 10319–10351, https://doi.org/10.5194/acp-22-10319-2022, https://doi.org/10.5194/acp-22-10319-2022, 2022
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Using the COVID-19 lockdown periods as an example, we show how Sentinel-5P/TROPOMI trace gas data (NO2, SO2, CO, HCHO and CHOCHO) can be used to understand impacts on air quality for regions and cities around the globe. We also provide information for both experienced and inexperienced users about how we created the data using state-of-the-art algorithms, where to get the data, methods taking meteorological and seasonal variability into consideration, and insights for future studies.
Tianlang Zhao, Jingqiu Mao, William R. Simpson, Isabelle De Smedt, Lei Zhu, Thomas F. Hanisco, Glenn M. Wolfe, Jason M. St. Clair, Gonzalo González Abad, Caroline R. Nowlan, Barbara Barletta, Simone Meinardi, Donald R. Blake, Eric C. Apel, and Rebecca S. Hornbrook
Atmos. Chem. Phys., 22, 7163–7178, https://doi.org/10.5194/acp-22-7163-2022, https://doi.org/10.5194/acp-22-7163-2022, 2022
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Monitoring formaldehyde (HCHO) can help us understand Arctic vegetation change. Here, we compare satellite data and model and show that Alaska summertime HCHO is largely dominated by a background from methane oxidation during mild wildfire years and is dominated by wildfire (largely from direct emission of fire) during strong fire years. Consequently, it is challenging to use satellite HCHO to study vegetation change in the Arctic region.
Christophe Lerot, François Hendrick, Michel Van Roozendael, Leonardo M. A. Alvarado, Andreas Richter, Isabelle De Smedt, Nicolas Theys, Jonas Vlietinck, Huan Yu, Jeroen Van Gent, Trissevgeni Stavrakou, Jean-François Müller, Pieter Valks, Diego Loyola, Hitoshi Irie, Vinod Kumar, Thomas Wagner, Stefan F. Schreier, Vinayak Sinha, Ting Wang, Pucai Wang, and Christian Retscher
Atmos. Meas. Tech., 14, 7775–7807, https://doi.org/10.5194/amt-14-7775-2021, https://doi.org/10.5194/amt-14-7775-2021, 2021
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Global measurements of glyoxal tropospheric columns from the satellite instrument TROPOMI are presented. Such measurements can contribute to the estimation of atmospheric emissions of volatile organic compounds. This new glyoxal product has been fully characterized with a comprehensive error budget, with comparison with other satellite data sets as well as with validation based on independent ground-based remote sensing glyoxal observations.
Nicolas Theys, Vitali Fioletov, Can Li, Isabelle De Smedt, Christophe Lerot, Chris McLinden, Nickolay Krotkov, Debora Griffin, Lieven Clarisse, Pascal Hedelt, Diego Loyola, Thomas Wagner, Vinod Kumar, Antje Innes, Roberto Ribas, François Hendrick, Jonas Vlietinck, Hugues Brenot, and Michel Van Roozendael
Atmos. Chem. Phys., 21, 16727–16744, https://doi.org/10.5194/acp-21-16727-2021, https://doi.org/10.5194/acp-21-16727-2021, 2021
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We present a new algorithm to retrieve sulfur dioxide from space UV measurements. We apply the technique to high-resolution TROPOMI measurements and demonstrate the high sensitivity of the approach to weak SO2 emissions worldwide with an unprecedented limit of detection of 8 kt yr−1. This result has broad implications for atmospheric science studies dealing with improving emission inventories and identifying and quantifying missing sources, in the context of air quality and climate.
Isabelle De Smedt, Gaia Pinardi, Corinne Vigouroux, Steven Compernolle, Alkis Bais, Nuria Benavent, Folkert Boersma, Ka-Lok Chan, Sebastian Donner, Kai-Uwe Eichmann, Pascal Hedelt, François Hendrick, Hitoshi Irie, Vinod Kumar, Jean-Christopher Lambert, Bavo Langerock, Christophe Lerot, Cheng Liu, Diego Loyola, Ankie Piters, Andreas Richter, Claudia Rivera Cárdenas, Fabian Romahn, Robert George Ryan, Vinayak Sinha, Nicolas Theys, Jonas Vlietinck, Thomas Wagner, Ting Wang, Huan Yu, and Michel Van Roozendael
Atmos. Chem. Phys., 21, 12561–12593, https://doi.org/10.5194/acp-21-12561-2021, https://doi.org/10.5194/acp-21-12561-2021, 2021
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This paper assess the performances of the TROPOMI formaldehyde observations compared to its predecessor OMI at different spatial and temporal scales. We also use a global network of MAX-DOAS instruments to validate both satellite datasets for a large range of HCHO columns. The precision obtained with daily TROPOMI observations is comparable to monthly OMI observations. We present clear detection of weak HCHO column enhancements related to shipping emissions in the Indian Ocean.
Robert J. Parker, Alex Webb, Hartmut Boesch, Peter Somkuti, Rocio Barrio Guillo, Antonio Di Noia, Nikoleta Kalaitzi, Jasdeep S. Anand, Peter Bergamaschi, Frederic Chevallier, Paul I. Palmer, Liang Feng, Nicholas M. Deutscher, Dietrich G. Feist, David W. T. Griffith, Frank Hase, Rigel Kivi, Isamu Morino, Justus Notholt, Young-Suk Oh, Hirofumi Ohyama, Christof Petri, David F. Pollard, Coleen Roehl, Mahesh K. Sha, Kei Shiomi, Kimberly Strong, Ralf Sussmann, Yao Té, Voltaire A. Velazco, Thorsten Warneke, Paul O. Wennberg, and Debra Wunch
Earth Syst. Sci. Data, 12, 3383–3412, https://doi.org/10.5194/essd-12-3383-2020, https://doi.org/10.5194/essd-12-3383-2020, 2020
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This work presents the latest release of the University of Leicester GOSAT methane data and acts as the definitive description of this dataset. We detail the processing, validation and evaluation involved in producing these data and highlight its many applications. With now over a decade of global atmospheric methane observations, this dataset has helped, and will continue to help, us better understand the global methane budget and investigate how it may respond to a future changing climate.
Robert J. Parker, Chris Wilson, A. Anthony Bloom, Edward Comyn-Platt, Garry Hayman, Joe McNorton, Hartmut Boesch, and Martyn P. Chipperfield
Biogeosciences, 17, 5669–5691, https://doi.org/10.5194/bg-17-5669-2020, https://doi.org/10.5194/bg-17-5669-2020, 2020
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Wetlands contribute the largest uncertainty to the atmospheric methane budget. WetCHARTs is a simple, data-driven model that estimates wetland emissions using observations of precipitation and temperature. We perform the first detailed evaluation of WetCHARTs against satellite data and find it performs well in reproducing the observed wetland methane seasonal cycle for the majority of wetland regions. In regions where it performs poorly, we highlight incorrect wetland extent as a key reason.
Ke Li, Daniel J. Jacob, Lu Shen, Xiao Lu, Isabelle De Smedt, and Hong Liao
Atmos. Chem. Phys., 20, 11423–11433, https://doi.org/10.5194/acp-20-11423-2020, https://doi.org/10.5194/acp-20-11423-2020, 2020
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Surface summer ozone increased in China from 2013 to 2019 despite new governmental efforts targeting ozone pollution. We find that the ozone increase is mostly due to anthropogenic drivers, although meteorology also plays a role. Further analysis for the North China Plain shows that PM2.5 continued to decrease through 2019, while emissions of volatile organic compounds (VOCs) stayed flat. This could explain the anthropogenic increase in ozone, as PM2.5 scavenges the radical precursors of ozone.
Ka Lok Chan, Matthias Wiegner, Jos van Geffen, Isabelle De Smedt, Carlos Alberti, Zhibin Cheng, Sheng Ye, and Mark Wenig
Atmos. Meas. Tech., 13, 4499–4520, https://doi.org/10.5194/amt-13-4499-2020, https://doi.org/10.5194/amt-13-4499-2020, 2020
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The paper presents 2D MAX-DOAS observations of vertical distributions of aerosol extinction, NO2 and HCHO in Munich. The measured surface aerosol extinction coefficients and NO2 mixing ratios are compared to in situ monitoring data. The NO2 and HCHO data are subsequently used to validate satellite measurements. The MAX-DOAS measurements are also used to investigate the spatiotemporal characteristic of NO2 and HCHO in Munich.
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.
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.
Yang Wang, Steffen Dörner, Sebastian Donner, Sebastian Böhnke, Isabelle De Smedt, Russell R. Dickerson, Zipeng Dong, Hao He, Zhanqing Li, Zhengqiang Li, Donghui Li, Dong Liu, Xinrong Ren, Nicolas Theys, Yuying Wang, Yang Wang, Zhenzhu Wang, Hua Xu, Jiwei Xu, and Thomas Wagner
Atmos. Chem. Phys., 19, 5417–5449, https://doi.org/10.5194/acp-19-5417-2019, https://doi.org/10.5194/acp-19-5417-2019, 2019
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A MAX-DOAS instrument was operated to derive tropospheric vertical profiles of NO2, SO2, HONO, HCHO, CHOCHO and aerosols in the central western North China Plain in May and June 2016. The MAX-DOAS results are verified by comparisons with a collocated Raman lidar, overpass aircraft measurements, a sun photometer and in situ measurements. The contributions of regional transports and local emissions to the pollutants are evaluated based on case studies and statistic analysis.
Song Liu, Pieter Valks, Gaia Pinardi, Isabelle De Smedt, Huan Yu, Steffen Beirle, and Andreas Richter
Atmos. Meas. Tech., 12, 1029–1057, https://doi.org/10.5194/amt-12-1029-2019, https://doi.org/10.5194/amt-12-1029-2019, 2019
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Nitrogen dioxide (NO2) plays significant roles in both stratospheric and tropospheric chemistry, and the observations from satellites enable reliable monitoring of NO2 columns on a global scale and on long time scales. This work presents a refined algorithm for the retrieval of NO2 columns from the satellite instrument Global Ozone Monitoring Experiment-2 (GOME-2), which shows a clear improvement comparing to the previous algorithm.
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.
Neil Humpage, Hartmut Boesch, Paul I. Palmer, Andy Vick, Phil Parr-Burman, Martyn Wells, David Pearson, Jonathan Strachan, and Naidu Bezawada
Atmos. Meas. Tech., 11, 5199–5222, https://doi.org/10.5194/amt-11-5199-2018, https://doi.org/10.5194/amt-11-5199-2018, 2018
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We present an overview of the GreenHouse gas Observations of the Stratosphere and Troposphere (GHOST) instrument, a novel shortwave infrared grating spectrometer designed for remote sensing of total column greenhouse gas concentrations from an aircraft. Using laboratory measurements we show that the GHOST design is able to achieve its science objectives. We conclude by describing GHOST's maiden flights on board the NASA Global Hawk UAV during CAST/ATTREX and show some of the initial results.
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.
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.
Hannah Sonderfeld, Hartmut Bösch, Antoine P. R. Jeanjean, Stuart N. Riddick, Grant Allen, Sébastien Ars, Stewart Davies, Neil Harris, Neil Humpage, Roland Leigh, and Joseph Pitt
Atmos. Meas. Tech., 10, 3931–3946, https://doi.org/10.5194/amt-10-3931-2017, https://doi.org/10.5194/amt-10-3931-2017, 2017
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The waste sector is the second largest source of methane in the UK. However, uncertainties of methane emissions from landfill sites still remain. In this study we present a new approach for the estimation of methane emissions from a landfill site by applying a computational fluid dynamics (CFD) model for precise measurements of methane with in situ Fourier-transform infrared (FTIR) spectroscopy. Different source areas could be distinguished with this method and their emissions were assessed.
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.
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.
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.
Lei Zhu, Daniel J. Jacob, Patrick S. Kim, Jenny A. Fisher, Karen Yu, Katherine R. Travis, Loretta J. Mickley, Robert M. Yantosca, Melissa P. Sulprizio, Isabelle De Smedt, Gonzalo González Abad, Kelly Chance, Can Li, Richard Ferrare, Alan Fried, Johnathan W. Hair, Thomas F. Hanisco, Dirk Richter, Amy Jo Scarino, James Walega, Petter Weibring, and Glenn M. Wolfe
Atmos. Chem. Phys., 16, 13477–13490, https://doi.org/10.5194/acp-16-13477-2016, https://doi.org/10.5194/acp-16-13477-2016, 2016
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HCHO column data are widely used as a proxy for VOCs emissions, but validation of the data has been extremely limited. We use accurate aircraft observations to validate and intercompare 6 HCHO retrievals with GEOS-Chem as the intercomparison platform. Retrievals are interconsistent in spatial variability over the SE US and in daily variability, but are biased low by 20–51 %. Our work supports the use of HCHO column as a quantitative proxy for isoprene emission after correction of the low bias.
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.
Robert J. Parker, Hartmut Boesch, Martin J. Wooster, David P. Moore, Alex J. Webb, David Gaveau, and Daniel Murdiyarso
Atmos. Chem. Phys., 16, 10111–10131, https://doi.org/10.5194/acp-16-10111-2016, https://doi.org/10.5194/acp-16-10111-2016, 2016
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The current El Niño event has had a dramatic impact on the amount of Indonesian biomass burning and subsequent greenhouse gas emission. We have used satellite observations of CH4 and CO2 of these fires to probe aspects of their chemical composition. We show large enhancements in the amount of these species, due to the fire emissions. The ability to determine large-scale emission ratios from space allows the combustion behaviour of very large regions of burning to be characterised and understood.
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.
R. J. Parker, H. Boesch, K. Byckling, A. J. Webb, P. I. Palmer, L. Feng, P. Bergamaschi, F. Chevallier, J. Notholt, N. Deutscher, T. Warneke, F. Hase, R. Sussmann, S. Kawakami, R. Kivi, D. W. T. Griffith, and V. Velazco
Atmos. Meas. Tech., 8, 4785–4801, https://doi.org/10.5194/amt-8-4785-2015, https://doi.org/10.5194/amt-8-4785-2015, 2015
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Atmospheric CH4 is an important greenhouse gas. Long-term global observations are necessary to understand its behaviour, with satellite observations playing a key role. The "proxy" retrieval method is one of the most successful but relies on the contribution from atmospheric CO2 models. This work assesses the significance of the uncertainty from the model CO2 within the retrieval and determines that despite this uncertainty the data are still valuable for determining sources and sinks of CH4.
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.
W. Hewson, M. P. Barkley, G. Gonzalez Abad, H. Bösch, T. Kurosu, R. Spurr, and L. G. Tilstra
Atmos. Meas. Tech., 8, 4055–4074, https://doi.org/10.5194/amt-8-4055-2015, https://doi.org/10.5194/amt-8-4055-2015, 2015
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This work presents the air mass factor (AMF) algorithm in use at the University of Leicester, which introduces scene-specific variables into a per-observation full radiative transfer AMF calculation, including increasing spatial resolution of key environmental parameter databases, input variable area weighting, instrument-specific scattering weight calculation, and inclusion of an ozone vertical profile climatology.
Y. Zheng, N. Unger, M. P. Barkley, and X. Yue
Atmos. Chem. Phys., 15, 8559–8576, https://doi.org/10.5194/acp-15-8559-2015, https://doi.org/10.5194/acp-15-8559-2015, 2015
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We apply two global observational data sets, gross primary productivity (GPP) and tropospheric formaldehyde column variability (HCHOv), to probe isoprene emission variability on large spatiotemporal scales. GPP and HCHOv are decoupled or weakly anticorrelated in regions and seasons when isoprene emission is high. Isoprene emission models that include soil moisture dependence demonstrate greater skill in reproducing observed seasonal GPP-HCHOv correlations in the southeast US and the Amazon.
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.
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.
A. Geddes and H. Bösch
Atmos. Meas. Tech., 8, 859–874, https://doi.org/10.5194/amt-8-859-2015, https://doi.org/10.5194/amt-8-859-2015, 2015
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
H. Boesch, N. M. Deutscher, T. Warneke, K. Byckling, A. J. Cogan, D. W. T. Griffith, J. Notholt, R. J. Parker, and Z. Wang
Atmos. Meas. Tech., 6, 599–612, https://doi.org/10.5194/amt-6-599-2013, https://doi.org/10.5194/amt-6-599-2013, 2013
Related subject area
Subject: Gases | Technique: Remote Sensing | Topic: Validation and Intercomparisons
Validation of the version 4.5 MAESTRO ozone and NO2 measurements
Advancing CH4 and N2O retrieval strategies for NDACC/IRWG high-resolution direct-sun FTIR Observations
Long-term evolution of the calibration constant on a mobile/field campaign water vapour Raman lidar
Benchmarking data-driven inversion methods for the estimation of local CO2 emissions from synthetic satellite images of XCO2 and NO2
Validation of 12 years (2008–2019) of IASI-A CO with IAGOS aircraft observations
Diurnal variations of NO2 tropospheric vertical column density over the Seoul metropolitan area from the Geostationary Environment Monitoring Spectrometer (GEMS): seasonal differences and the influence of the a priori NO2 profile
Validation of ACE-FTS version 5.2 ozone data with ozonesonde measurements
Intercomparison of long-term ground-based measurements of total, tropospheric, and stratospheric ozone at Lauder, New Zealand
First evaluation of the GEMS glyoxal products against TROPOMI and ground-based measurements
Validation of GEMS tropospheric NO2 columns and their diurnal variation with ground-based DOAS measurements
Using open-path dual-comb spectroscopy to monitor methane emissions from simulated grazing cattle
Atmospheric horizontal gradients measured with eight co-located GNSS stations and a microwave radiometer
Greenhouse gas column observations from a portable spectrometer in Uganda
Independent validation of IASI/MetOp-A LMD and RAL CH4 products using CAMS model, in situ profiles, and ground-based FTIR measurements
Joint spectral retrievals of ozone with Suomi NPP CrIS augmented by S5P/TROPOMI
An evaluation of atmospheric absorption models at millimetre and sub-millimetre wavelengths using airborne observations
Applicability of the inverse dispersion method to measure emissions from animal housings
5 years of Sentinel-5P TROPOMI operational ozone profiling and geophysical validation using ozonesonde and lidar ground-based networks
Using a portable FTIR spectrometer to evaluate the consistency of Total Carbon Column Observing Network (TCCON) measurements on a global scale: the Collaborative Carbon Column Observing Network (COCCON) travel standard
Comparison of the H2O, HDO and δD stratospheric climatologies between the MIPAS-ESA V8, MIPAS-IMK V5 and ACE-FTS V4.1/4.2 satellite datasets
TROPESS-CrIS CO single-pixel vertical profiles: intercomparisons with MOPITT and model simulations for 2020 western US wildfires
TOLNet validation of satellite ozone profiles in the troposphere: impact of retrieval wavelengths
An uncertainty methodology for solar occultation flux measurements: ammonia emissions from livestock production
Validation of Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) chlorodifluoromethane (HCFC-22) in the upper troposphere and lower stratosphere
First validation of high-resolution satellite-derived methane emissions from an active gas leak in the UK
Ship- and aircraft-based XCH4 over oceans as a new tool for satellite validation
Single-blind test of nine methane-sensing satellite systems from three continents
Water vapor measurements inside clouds and storms using a differential absorption radar
Evaluation of the first year of Pandora NO2 measurements over Beijing and application to satellite validation
Validation of MUSES NH3 observations from AIRS and CrIS against aircraft measurements from DISCOVER-AQ and a surface network in the Magic Valley
Performance and sensitivity of column-wise and pixel-wise methane retrievals for imaging spectrometers
Methane point source quantification using MethaneAIR: a new airborne imaging spectrometer
Evaluation of total ozone measurements from Geostationary Environmental Monitoring Spectrometer (GEMS)
To new heights by flying low: comparison of aircraft vertical NO2 profiles to model simulations and implications for TROPOMI NO2 retrievals
Local comparisons of tropospheric ozone: vertical soundings at two neighbouring stations in southern Bavaria
Ground-based Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) observations of NO2 and H2CO at Kinshasa and comparisons with TROPOMI observations
Total column ozone trends from the NASA Merged Ozone time series 1979 to 2021 showing latitude-dependent ozone recovery dates (1994 to 1998)
The SPARC water vapour assessment II: biases and drifts of water vapour satellite data records with respect to frost point hygrometer records
Vicarious calibration of the Tropospheric Monitoring Instrument (TROPOMI) short-wave infrared (SWIR) module over the Railroad Valley Playa
First-time comparison between NO2 vertical columns from Geostationary Environmental Monitoring Spectrometer (GEMS) and Pandora measurements
A blended TROPOMI+GOSAT satellite data product for atmospheric methane using machine learning to correct retrieval biases
Evaluating the consistency between OCO-2 and OCO-3 XCO2 estimates derived from the NASA ACOS version 10 retrieval algorithm
OLCI-A/B tandem phase: evaluation of FLuorescence EXplorer (FLEX)-like radiances and estimation of systematic differences between OLCI-A and OLCI-FLEX
Multi-parameter dynamical diagnostics for upper tropospheric and lower stratospheric studies
An approach to track instrument calibration and produce consistent products with the version-8 total column ozone algorithm (V8TOZ)
Satellite remote-sensing capability to assess tropospheric-column ratios of formaldehyde and nitrogen dioxide: case study during the Long Island Sound Tropospheric Ozone Study 2018 (LISTOS 2018) field campaign
Validation of Sentinel-5P TROPOMI tropospheric NO2 products by comparison with NO2 measurements from airborne imaging DOAS, ground-based stationary DOAS, and mobile car DOAS measurements during the S5P-VAL-DE-Ruhr campaign
Evaluation of open- and closed-path sampling systems for the determination of emission rates of NH3 and CH4 with inverse dispersion modeling
Performance of AIRS ozone retrieval over the central Himalayas: use of ozonesonde and other satellite datasets
Solar occultation measurement of mesospheric ozone by SAGE III/ISS: impact of variations along the line of sight caused by photochemistry
Paul S. Jeffery, James R. Drummond, C. Thomas McElroy, Kaley A. Walker, and Jiansheng Zou
Atmos. Meas. Tech., 18, 569–602, https://doi.org/10.5194/amt-18-569-2025, https://doi.org/10.5194/amt-18-569-2025, 2025
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The MAESTRO instrument has been monitoring ozone and NO2 since February 2004. A new version of these data products has recently been released; however, these new products must be validated against other datasets to ensure their validity. This study presents such an assessment, using measurements from 11 satellite instruments to characterize the new MAESTRO products. In the stratosphere, good agreement is found for ozone and acceptable agreement is found for NO2 with these other datasets.
Ivan Ortega, James W. Hannigan, Bianca C. Baier, Kathryn McKain, and Dan Smale
EGUsphere, https://doi.org/10.5194/egusphere-2024-3815, https://doi.org/10.5194/egusphere-2024-3815, 2025
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The study evaluates retrieval strategies for atmospheric CH4 and N2O using high-resolution FTIR observations and comparing results with long-term AirCore and aircraft measurements. Updated a priori data and spectroscopic databases (HITRAN 2020, ATM 2020) improve accuracy. Findings highlight low biases within a few percent, quantified uncertainties, and consistent retrievals for Boulder, Colorado, extended to Lauder, New Zealand, advancing harmonized approaches for NDACC sites.
Patrick Chazette, Julien Totems, and Frédéric Laly
EGUsphere, https://doi.org/10.5194/egusphere-2024-3583, https://doi.org/10.5194/egusphere-2024-3583, 2025
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The use of active remote sensing instruments to sample the atmospheric environment requires accurate calibration that is stable over time so that measurements are reproducible. This is the case for measurements of atmospheric water vapour using Raman lidar, which are of growing interest in the context of climate risks such as extreme precipitation. This study addresses this issue. It is based on 6 campaigns spread over a period of 7 years between 2016 and 2022.
Diego Santaren, Janne Hakkarainen, Gerrit Kuhlmann, Erik Koene, Frédéric Chevallier, Iolanda Ialongo, Hannakaisa Lindqvist, Janne Nurmela, Johanna Tamminen, Laia Amorós, Dominik Brunner, and Grégoire Broquet
Atmos. Meas. Tech., 18, 211–239, https://doi.org/10.5194/amt-18-211-2025, https://doi.org/10.5194/amt-18-211-2025, 2025
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This study evaluates data-driven inversion methods for estimating CO2 emissions from local sources, such as power plants and cities, using meteorological data and XCO2 and NO2 satellite images rather than atmospheric transport modeling. We assess and compare the performance of five different methods using simulations of 1 year of satellite images, taken from the upcoming Copernicus CO2 Monitoring Mission, covering 15 power plants and the city of Berlin, Germany.
Brice Barret, Pierre Loicq, Eric Le Flochmoën, Yasmine Bennouna, Juliette Hadji-Lazaro, Daniel Hurtmans, and Bastien Sauvage
Atmos. Meas. Tech., 18, 129–149, https://doi.org/10.5194/amt-18-129-2025, https://doi.org/10.5194/amt-18-129-2025, 2025
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Profiles of carbon monoxide (CO) retrieved from the Infrared Atmospheric Sounding Interferometer (IASI) with the SOftware for a Fast Retrieval of IASI Data (SOFRID) and Fast Optimal Retrievals on Layers for IASI (FORLI) are validated with 8500 observations at 33 airports from the In-service Aircraft for a Global Observing System (IAGOS) for 2008–2019. IASI retrievals underestimate CO, with stronger bias in the middle to upper troposphere for SOFRID and in the lower troposphere for FORLI.
Seunghwan Seo, Si-Wan Kim, Kyoung-Min Kim, Andreas Richter, Kezia Lange, John P. Burrows, Junsung Park, Hyunkee Hong, Hanlim Lee, Ukkyo Jeong, Jung-Hun Woo, and Jhoon Kim
Atmos. Meas. Tech., 18, 115–128, https://doi.org/10.5194/amt-18-115-2025, https://doi.org/10.5194/amt-18-115-2025, 2025
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Over the Seoul metropolitan area, tropospheric NO2 vertical column densities from the Geostationary Environment Monitoring Spectrometer show distinct seasonal features. Also, varying a priori data have substantial impacts on the observed NO2 columns. The a priori data from different chemical transport models resulted in differences of up to −18.3 %. Notably, diurnal patterns of observed NO2 columns are similar for all datasets, although their a priori data exhibit contrasting diurnal patterns.
Jiansheng Zou, Kaley A. Walker, Patrick E. Sheese, Chris D. Boone, Ryan M. Stauffer, Anne M. Thompson, and David W. Tarasick
Atmos. Meas. Tech., 17, 6983–7005, https://doi.org/10.5194/amt-17-6983-2024, https://doi.org/10.5194/amt-17-6983-2024, 2024
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Ozone measurements from the ACE-FTS satellite instrument have been compared to worldwide balloon-borne ozonesonde profiles using pairs of closely spaced profiles and monthly averaged profiles. ACE-FTS typically measures more ozone in the stratosphere by up to 10 %. The long-term stability of the ACE-FTS ozone data is good, exhibiting small (but non-significant) drifts of less than 3 % per decade in the stratosphere. Lower in the profiles, the calculated drifts are larger (up to 10 % per decade).
Robin Björklund, Corinne Vigouroux, Peter Effertz, Omaira E. García, Alex Geddes, James Hannigan, Koji Miyagawa, Michael Kotkamp, Bavo Langerock, Gerald Nedoluha, Ivan Ortega, Irina Petropavlovskikh, Deniz Poyraz, Richard Querel, John Robinson, Hisako Shiona, Dan Smale, Penny Smale, Roeland Van Malderen, and Martine De Mazière
Atmos. Meas. Tech., 17, 6819–6849, https://doi.org/10.5194/amt-17-6819-2024, https://doi.org/10.5194/amt-17-6819-2024, 2024
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Different ground-based ozone measurements from the last 2 decades at Lauder are compared to each other. We want to know why different trends have been observed in the stratosphere. Also, the quality and relevance of tropospheric datasets need to be evaluated. While remaining drifts are still present, our study explains roughly half of the differences in observed trends in previous studies and shows the necessity for continuous review and improvement of the measurements.
Eunjo S. Ha, Rokjin J. Park, Hyeong-Ahn Kwon, Gitaek T. Lee, Sieun D. Lee, Seunga Shin, Dong-Won Lee, Hyunkee Hong, Christophe Lerot, Isabelle De Smedt, Thomas Danckaert, Francois Hendrick, and Hitoshi Irie
Atmos. Meas. Tech., 17, 6369–6384, https://doi.org/10.5194/amt-17-6369-2024, https://doi.org/10.5194/amt-17-6369-2024, 2024
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In this study, we evaluated the GEMS glyoxal products by comparing them with TROPOMI and MAX-DOAS measurements. GEMS and TROPOMI VCDs present similar spatial distributions. Monthly variations in GEMS VCDs and TROPOMI and MAX-DOAS VCDs differ in northeastern Asia, which we attributed to a polluted reference spectrum and high NO2 concentrations. GEMS glyoxal products with unparalleled temporal resolution would enrich our understanding of VOC emissions and diurnal variation.
Kezia Lange, Andreas Richter, Tim Bösch, Bianca Zilker, Miriam Latsch, Lisa K. Behrens, Chisom M. Okafor, Hartmut Bösch, John P. Burrows, Alexis Merlaud, Gaia Pinardi, Caroline Fayt, Martina M. Friedrich, Ermioni Dimitropoulou, Michel Van Roozendael, Steffen Ziegler, Simona Ripperger-Lukosiunaite, Leon Kuhn, Bianca Lauster, Thomas Wagner, Hyunkee Hong, Donghee Kim, Lim-Seok Chang, Kangho Bae, Chang-Keun Song, Jong-Uk Park, and Hanlim Lee
Atmos. Meas. Tech., 17, 6315–6344, https://doi.org/10.5194/amt-17-6315-2024, https://doi.org/10.5194/amt-17-6315-2024, 2024
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Instruments for air quality observations on geostationary satellites provide multiple observations per day and allow for the analysis of the diurnal variation of important air pollutants such as nitrogen dioxide (NO2) over large areas. The South Korean instrument GEMS, launched in February 2020, is the first instrument in geostationary orbit and covers a large part of Asia. Our investigations show the observed diurnal evolution of NO2 at different measurement sites.
Chinthaka Weerasekara, Lindsay C. Morris, Nathan A. Malarich, Fabrizio R. Giorgetta, Daniel I. Herman, Kevin C. Cossel, Nathan R. Newbury, Clenton E. Owensby, Stephen M. Welch, Cosmin Blaga, Brett D. DePaola, Ian Coddington, Brian R. Washburn, and Eduardo A. Santos
Atmos. Meas. Tech., 17, 6107–6117, https://doi.org/10.5194/amt-17-6107-2024, https://doi.org/10.5194/amt-17-6107-2024, 2024
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Most methane emissions during the life cycle of beef cattle occur during the grazing phase. Measuring methane in grazing systems is difficult due to the high mobility and low density of animals. This work investigates if dual-comb spectroscopy can measure methane emissions from small cattle herds. An enhancement of 10 nmol mol-1 methane above the atmospheric background was measured, equivalent to 20 head located 60 m away. The calculated methane flux was within 5 % of the actual release rate.
Ning Tong and Gunnar Elgered
EGUsphere, https://doi.org/10.5194/egusphere-2024-2716, https://doi.org/10.5194/egusphere-2024-2716, 2024
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The gradients estimated from multi-GNSS data were compared to WVR data. A better agreement is obtained when using WVR data with a smaller value of liquid water content. A weak constraint in GNSS data processing may be desirable for applications with a higher tolerance for formal errors but a greater focus on tracking the variability of water vapour. The averaged GNSS gradients can significantly reduce the random noise which can be used to obtain a more reliable variability of the water vapour.
Neil Humpage, Hartmut Boesch, William Okello, Jia Chen, Florian Dietrich, Mark F. Lunt, Liang Feng, Paul I. Palmer, and Frank Hase
Atmos. Meas. Tech., 17, 5679–5707, https://doi.org/10.5194/amt-17-5679-2024, https://doi.org/10.5194/amt-17-5679-2024, 2024
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We used a Bruker EM27/SUN spectrometer within an automated weatherproof enclosure to measure greenhouse gas column concentrations over a 3-month period in Jinja, Uganda. The portability of the EM27/SUN allows us to evaluate satellite and model data in locations not covered by traditional validation networks. This is of particular value in tropical Africa, where extensive terrestrial ecosystems are a significant store of carbon and play a key role in the atmospheric budgets of CO2 and CH4.
Bart Dils, Minqiang Zhou, Claude Camy-Peyret, Martine De Mazière, Yannick Kangah, Bavo Langerock, Pascal Prunet, Carmine Serio, Richard Siddans, and Brian Kerridge
Atmos. Meas. Tech., 17, 5491–5524, https://doi.org/10.5194/amt-17-5491-2024, https://doi.org/10.5194/amt-17-5491-2024, 2024
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The paper discusses two very distinct methane products from the IASI instrument aboard the MetOp-A satellite. One (referred to as LMD NLISv8.3) uses a machine-learning approach, while the other (RALv2.0) uses a more conventional optimal estimation approach. We used a variety of model and independent reference measurement data to assess both products' overall quality, their differences, and specific aspects of each product that would benefit from further analysis by the product development teams.
Edward Malina, Kevin W. Bowman, Valentin Kantchev, Le Kuai, Thomas P. Kurosu, Kazuyuki Miyazaki, Vijay Natraj, Gregory B. Osterman, Fabiano Oyafuso, and Matthew D. Thill
Atmos. Meas. Tech., 17, 5341–5371, https://doi.org/10.5194/amt-17-5341-2024, https://doi.org/10.5194/amt-17-5341-2024, 2024
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Characterizing the distribution of ozone in the atmosphere is a challenging problem, with current Earth observation satellites using either thermal infrared (TIR) or ultraviolet (UV) instruments, sensitive to different portions of the atmosphere, making it difficult to gain a full picture. In this work, we combine measurements from the TIR and UV instruments Suomi NPP CrIS and Sentinel-5P/TROPOMI to improve sensitivity through the whole atmosphere and improve knowledge of ozone distribution.
Stuart Fox, Vinia Mattioli, Emma Turner, Alan Vance, Domenico Cimini, and Donatello Gallucci
Atmos. Meas. Tech., 17, 4957–4978, https://doi.org/10.5194/amt-17-4957-2024, https://doi.org/10.5194/amt-17-4957-2024, 2024
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Airborne observations are used to evaluate two models for absorption and emission by atmospheric gases, including water vapour and oxygen, at microwave and sub-millimetre wavelengths. These models are needed for the Ice Cloud Imager (ICI) on the next generation of European polar-orbiting weather satellites, which measures at frequencies up to 664 GHz. Both models can provide a good match to measurements from airborne radiometers and are sufficiently accurate for use with ICI.
Marcel Bühler, Christoph Häni, Albrecht Neftel, Patrice Bühler, Christof Ammann, and Thomas Kupper
Atmos. Meas. Tech., 17, 4649–4658, https://doi.org/10.5194/amt-17-4649-2024, https://doi.org/10.5194/amt-17-4649-2024, 2024
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Methane was released from an artificial source inside a barn to test the applicability of the inverse dispersion method (IDM). Multiple open-path concentration devices and ultrasonic anemometers were used at the site. It is concluded that, for the present study case, the effect of a building and a tree in the main wind axis led to a systematic underestimation of the IDM-derived emission rate probably due to deviations in the wind field and turbulent dispersion from the ideal assumptions.
Arno Keppens, Serena Di Pede, Daan Hubert, Jean-Christopher Lambert, Pepijn Veefkind, Maarten Sneep, Johan De Haan, Mark ter Linden, Thierry Leblanc, Steven Compernolle, Tijl Verhoelst, José Granville, Oindrila Nath, Ann Mari Fjæraa, Ian Boyd, Sander Niemeijer, Roeland Van Malderen, Herman G. J. Smit, Valentin Duflot, Sophie Godin-Beekmann, Bryan J. Johnson, Wolfgang Steinbrecht, David W. Tarasick, Debra E. Kollonige, Ryan M. Stauffer, Anne M. Thompson, Angelika Dehn, and Claus Zehner
Atmos. Meas. Tech., 17, 3969–3993, https://doi.org/10.5194/amt-17-3969-2024, https://doi.org/10.5194/amt-17-3969-2024, 2024
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The Sentinel-5P satellite operated by the European Space Agency has carried the TROPOspheric Monitoring Instrument (TROPOMI) around the Earth since October 2017. This mission also produces atmospheric ozone profile data which are described in detail for May 2018 to April 2023. Independent validation using ground-based reference measurements demonstrates that the operational ozone profile product mostly fully and at least partially complies with all mission requirements.
Benedikt Herkommer, Carlos Alberti, Paolo Castracane, Jia Chen, Angelika Dehn, Florian Dietrich, Nicholas M. Deutscher, Matthias Max Frey, Jochen Groß, Lawson Gillespie, Frank Hase, Isamu Morino, Nasrin Mostafavi Pak, Brittany Walker, and Debra Wunch
Atmos. Meas. Tech., 17, 3467–3494, https://doi.org/10.5194/amt-17-3467-2024, https://doi.org/10.5194/amt-17-3467-2024, 2024
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The Total Carbon Column Observing Network is a network of ground-based Fourier transform infrared (FTIR) spectrometers used mainly for satellite validation. To ensure the highest-quality validation data, the network needs to be highly consistent. This is a major challenge, which so far is solved by site comparisons with airborne in situ measurements. In this work, we describe the use of a portable FTIR spectrometer as a travel standard for evaluating the consistency of TCCON sites.
Karen De Los Ríos, Paulina Ordoñez, Gabriele P. Stiller, Piera Raspollini, Marco Gai, Kaley A. Walker, Cristina Peña-Ortiz, and Luis Acosta
Atmos. Meas. Tech., 17, 3401–3418, https://doi.org/10.5194/amt-17-3401-2024, https://doi.org/10.5194/amt-17-3401-2024, 2024
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This study examines newer versions of H2O and HDO retrievals from Envisat/MIPAS and SCISAT/ACE-FTS. Results reveal a better agreement in stratospheric H2O profiles than in HDO profiles. The H2O tape recorder signal is consistent across databases, but δD tape recorder composites show differences that impact the interpretation of water vapour transport. These findings enhance the need for intercomparisons to refine our insights.
Ming Luo, Helen M. Worden, Robert D. Field, Kostas Tsigaridis, and Gregory S. Elsaesser
Atmos. Meas. Tech., 17, 2611–2624, https://doi.org/10.5194/amt-17-2611-2024, https://doi.org/10.5194/amt-17-2611-2024, 2024
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The TROPESS CrIS single-pixel CO profile retrievals are compared to the MOPITT CO products in steps of adjusting them to the common a priori assumptions. The two data sets are found to agree within 5 %. We also demonstrated and analyzed the proper steps in evaluating GISS ModelE CO simulations using satellite CO retrieval products for the western US wildfire events in September 2020.
Matthew S. Johnson, Alexei Rozanov, Mark Weber, Nora Mettig, John Sullivan, Michael J. Newchurch, Shi Kuang, Thierry Leblanc, Fernando Chouza, Timothy A. Berkoff, Guillaume Gronoff, Kevin B. Strawbridge, Raul J. Alvarez, Andrew O. Langford, Christoph J. Senff, Guillaume Kirgis, Brandi McCarty, and Larry Twigg
Atmos. Meas. Tech., 17, 2559–2582, https://doi.org/10.5194/amt-17-2559-2024, https://doi.org/10.5194/amt-17-2559-2024, 2024
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Monitoring tropospheric ozone (O3), a harmful pollutant negatively impacting human health, is primarily done using ground-based measurements and ozonesondes. However, these observation types lack the coverage to fully understand tropospheric O3. Satellites can retrieve tropospheric ozone with near-daily global coverage; however, they are known to have biases and errors. This study uses ground-based lidars to validate multiple satellites' ability to observe tropospheric O3.
Johan Mellqvist, Nathalia T. Vechi, Charlotte Scheutz, Marc Durif, Francois Gautier, John Johansson, Jerker Samuelsson, Brian Offerle, and Samuel Brohede
Atmos. Meas. Tech., 17, 2465–2479, https://doi.org/10.5194/amt-17-2465-2024, https://doi.org/10.5194/amt-17-2465-2024, 2024
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The solar occultation flux method retrieves ammonia gas columns from the solar spectrum. Emissions are obtained by multiplying the integrated plume concentration by the wind speed profile. The methodology for uncertainty estimation was established considering an error budget with systematic and random components, resulting in an expanded uncertainty in the range of 20 % to 30 %. The method was validated in a controlled release, and its application was demonstrated in different farms.
Felicia Kolonjari, Patrick E. Sheese, Kaley A. Walker, Chris D. Boone, David A. Plummer, Andreas Engel, Stephen A. Montzka, David E. Oram, Tanja Schuck, Gabriele P. Stiller, and Geoffrey C. Toon
Atmos. Meas. Tech., 17, 2429–2449, https://doi.org/10.5194/amt-17-2429-2024, https://doi.org/10.5194/amt-17-2429-2024, 2024
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The Canadian Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS) satellite instrument is currently providing the only vertically resolved chlorodifluoromethane (HCFC-22) measurements from space. This study assesses the most current ACE-FTS HCFC-22 data product in the upper troposphere and lower stratosphere, as well as modelled HCFC-22 from a 39-year run of the Canadian Middle Atmosphere Model (CMAM39) in the same region.
Emily Dowd, Alistair J. Manning, Bryn Orth-Lashley, Marianne Girard, James France, Rebecca E. Fisher, Dave Lowry, Mathias Lanoisellé, Joseph R. Pitt, Kieran M. Stanley, Simon O'Doherty, Dickon Young, Glen Thistlethwaite, Martyn P. Chipperfield, Emanuel Gloor, and Chris Wilson
Atmos. Meas. Tech., 17, 1599–1615, https://doi.org/10.5194/amt-17-1599-2024, https://doi.org/10.5194/amt-17-1599-2024, 2024
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We provide the first validation of the satellite-derived emission estimates using surface-based mobile greenhouse gas surveys of an active gas leak detected near Cheltenham, UK. GHGSat’s emission estimates broadly agree with the surface-based mobile survey and steps were taken to fix the leak, highlighting the importance of satellite data in identifying emissions and helping to reduce our human impact on climate change.
Astrid Müller, Hiroshi Tanimoto, Takafumi Sugita, Prabir K. Patra, Shin-ichiro Nakaoka, Toshinobu Machida, Isamu Morino, André Butz, and Kei Shiomi
Atmos. Meas. Tech., 17, 1297–1316, https://doi.org/10.5194/amt-17-1297-2024, https://doi.org/10.5194/amt-17-1297-2024, 2024
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Satellite CH4 observations with high accuracy are needed to understand changes in atmospheric CH4 concentrations. But over oceans, reference data are limited. We combine various ship and aircraft observations with the help of atmospheric chemistry models to derive observation-based column-averaged mixing ratios of CH4 (obs. XCH4). We discuss three different approaches and demonstrate the applicability of the new reference dataset for carbon cycle studies and satellite evaluation.
Evan D. Sherwin, Sahar H. El Abbadi, Philippine M. Burdeau, Zhan Zhang, Zhenlin Chen, Jeffrey S. Rutherford, Yuanlei Chen, and Adam R. Brandt
Atmos. Meas. Tech., 17, 765–782, https://doi.org/10.5194/amt-17-765-2024, https://doi.org/10.5194/amt-17-765-2024, 2024
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Countries and companies increasingly rely on a growing fleet of satellites to find large emissions of climate-warming methane, particularly from oil and natural gas systems across the globe. We independently assessed the performance of nine such systems by releasing controlled, undisclosed amounts of methane as satellites passed overhead. The tested systems produced reliable detection and quantification results, including the smallest-ever emission detected from space in such a test.
Luis F. Millán, Matthew D. Lebsock, Ken B. Cooper, Jose V. Siles, Robert Dengler, Raquel Rodriguez Monje, Amin Nehrir, Rory A. Barton-Grimley, James E. Collins, Claire E. Robinson, Kenneth L. Thornhill, and Holger Vömel
Atmos. Meas. Tech., 17, 539–559, https://doi.org/10.5194/amt-17-539-2024, https://doi.org/10.5194/amt-17-539-2024, 2024
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In this study, we describe and validate a new technique in which three radar tones are used to estimate the water vapor inside clouds and precipitation. This instrument flew on board NASA's P-3 aircraft during the Investigation of Microphysics and Precipitation for Atlantic Coast-Threatening Snowstorms (IMPACTS) campaign and the Synergies Of Active optical and Active microwave Remote Sensing Experiment (SOA2RSE) campaign.
Ouyang Liu, Zhengqiang Li, Yangyan Lin, Cheng Fan, Ying Zhang, Kaitao Li, Peng Zhang, Yuanyuan Wei, Tianzeng Chen, Jiantao Dong, and Gerrit de Leeuw
Atmos. Meas. Tech., 17, 377–395, https://doi.org/10.5194/amt-17-377-2024, https://doi.org/10.5194/amt-17-377-2024, 2024
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Nitrogen dioxide (NO2) is a trace gas which is important for atmospheric chemistry and may affect human health. To understand processes leading to harmful concentrations, it is important to monitor NO2 concentrations near the surface and higher up. To this end, a Pandora instrument has been installed in Beijing. An overview of the first year of data shows the large variability on diurnal to seasonal timescales and how this is affected by wind speed and direction and chemistry.
Karen E. Cady-Pereira, Xuehui Guo, Rui Wang, April B. Leytem, Chase Calkins, Elizabeth Berry, Kang Sun, Markus Müller, Armin Wisthaler, Vivienne H. Payne, Mark W. Shephard, Mark A. Zondlo, and Valentin Kantchev
Atmos. Meas. Tech., 17, 15–36, https://doi.org/10.5194/amt-17-15-2024, https://doi.org/10.5194/amt-17-15-2024, 2024
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Ammonia is a significant precursor of PM2.5 particles and thus contributes to poor air quality in many regions. Furthermore, ammonia concentrations are rising due to the increase of large-scale, intensive agricultural activities. Here we evaluate satellite measurements of ammonia against aircraft and surface network data, and show that there are differences in magnitude, but the satellite data are spatially and temporally well correlated with the in situ data.
Alana K. Ayasse, Daniel Cusworth, Kelly O'Neill, Justin Fisk, Andrew K. Thorpe, and Riley Duren
Atmos. Meas. Tech., 16, 6065–6074, https://doi.org/10.5194/amt-16-6065-2023, https://doi.org/10.5194/amt-16-6065-2023, 2023
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Methane is a powerful greenhouse gas, and a significant portion of methane comes from large individual plumes. Recently, airplane-mounted infrared technologies have proven very good at detecting and quantifying these plumes. In order to extract the methane signal from the infrared image, there are two widely used approaches. In this study, we assess the performance of both approaches using controlled-release experiments. We also examine the minimum detection limit of the infrared technology.
Apisada Chulakadabba, Maryann Sargent, Thomas Lauvaux, Joshua S. Benmergui, Jonathan E. Franklin, Christopher Chan Miller, Jonas S. Wilzewski, Sébastien Roche, Eamon Conway, Amir H. Souri, Kang Sun, Bingkun Luo, Jacob Hawthrone, Jenna Samra, Bruce C. Daube, Xiong Liu, Kelly Chance, Yang Li, Ritesh Gautam, Mark Omara, Jeff S. Rutherford, Evan D. Sherwin, Adam Brandt, and Steven C. Wofsy
Atmos. Meas. Tech., 16, 5771–5785, https://doi.org/10.5194/amt-16-5771-2023, https://doi.org/10.5194/amt-16-5771-2023, 2023
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We show that MethaneAIR, a precursor to the MethaneSAT satellite, demonstrates accurate point source quantification during controlled release experiments and regional observations in 2021 and 2022. Results from our two independent quantification methods suggest the accuracy of our sensor and algorithms is better than 25 % for sources emitting 200 kg h−1 or more. Insights from these measurements help establish the capabilities of MethaneSAT and MethaneAIR.
Kanghyun Baek, Jae Hwan Kim, Juseon Bak, David P. Haffner, Mina Kang, and Hyunkee Hong
Atmos. Meas. Tech., 16, 5461–5478, https://doi.org/10.5194/amt-16-5461-2023, https://doi.org/10.5194/amt-16-5461-2023, 2023
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The GEMS mission was the first mission of the geostationary satellite constellation for hourly atmospheric composition monitoring. The GEMS ozone measurements were cross-compared to those of Pandora, OMPS, and TROPOMI satellite sensors and excellent agreement was found. GEMS has proven to be a powerful new instrument for monitoring and assessing the diurnal variation in atmospheric ozone. This experience can be used to advance research with future geostationary environmental satellite missions.
Tobias Christoph Valentin Werner Riess, Klaas Folkert Boersma, Ward Van Roy, Jos de Laat, Enrico Dammers, and Jasper van Vliet
Atmos. Meas. Tech., 16, 5287–5304, https://doi.org/10.5194/amt-16-5287-2023, https://doi.org/10.5194/amt-16-5287-2023, 2023
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Satellite retrievals of trace gases require prior knowledge of the vertical distribution of the pollutant, which is usually obtained from models. Using aircraft-measured vertical NO2 profiles over the North Sea in summer 2021, we evaluate the Transport Model 5 profiles used in the TROPOMI NO2 retrieval. We conclude that driven by the low horizontal resolution and the overestimated vertical mixing, resulting NO2 columns are 20 % too low. This has important implications for emission estimates.
Thomas Trickl, Martin Adelwart, Dina Khordakova, Ludwig Ries, Christian Rolf, Michael Sprenger, Wolfgang Steinbrecht, and Hannes Vogelmann
Atmos. Meas. Tech., 16, 5145–5165, https://doi.org/10.5194/amt-16-5145-2023, https://doi.org/10.5194/amt-16-5145-2023, 2023
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Tropospheric ozone have been measured for more than a century. Highly quantitative ozone measurements have been made at monitoring stations. However, deficits have been reported for vertical sounding systems. Here, we report a thorough intercomparison effort between a differential-absorption lidar system and two types of balloon-borne ozone sondes, also using ozone sensors at nearby mountain sites as references. The sondes agree very well with the lidar after offset corrections.
Rodriguez Yombo Phaka, Alexis Merlaud, Gaia Pinardi, Martina M. Friedrich, Michel Van Roozendael, Jean-François Müller, Trissevgeni Stavrakou, Isabelle De Smedt, François Hendrick, Ermioni Dimitropoulou, Richard Bopili Mbotia Lepiba, Edmond Phuku Phuati, Buenimio Lomami Djibi, Lars Jacobs, Caroline Fayt, Jean-Pierre Mbungu Tsumbu, and Emmanuel Mahieu
Atmos. Meas. Tech., 16, 5029–5050, https://doi.org/10.5194/amt-16-5029-2023, https://doi.org/10.5194/amt-16-5029-2023, 2023
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We present air quality measurements in Kinshasa, Democratic Republic of the Congo, performed with a newly developed instrument which was installed on a roof of the University of Kinshasa in November 2019. The instrument records spectra of the scattered sunlight, from which we derive the abundances of nitrogen dioxide and formaldehyde, two important pollutants. We compare our ground-based measurements with those of the TROPOspheric Monitoring Instrument (TROPOMI).
Jay Herman, Jerald Ziemke, and Richard McPeters
Atmos. Meas. Tech., 16, 4693–4707, https://doi.org/10.5194/amt-16-4693-2023, https://doi.org/10.5194/amt-16-4693-2023, 2023
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Fourier series multivariate linear regression trends (% per decade) in ozone were estimated from the Merged Ozone Data Set (MOD) from 1979 to 2021 in two different regimes, from 1979 to TA (the date when ozone stopped decreasing) and TA to 2021. The derived TA is a latitude-dependent date, ranging from 1994 to 1998. TA(θ) is a marker for photochemistry dynamics models attempting to represent ozone change over the past 42 years.
Michael Kiefer, Dale F. Hurst, Gabriele P. Stiller, Stefan Lossow, Holger Vömel, John Anderson, Faiza Azam, Jean-Loup Bertaux, Laurent Blanot, Klaus Bramstedt, John P. Burrows, Robert Damadeo, Bianca Maria Dinelli, Patrick Eriksson, Maya García-Comas, John C. Gille, Mark Hervig, Yasuko Kasai, Farahnaz Khosrawi, Donal Murtagh, Gerald E. Nedoluha, Stefan Noël, Piera Raspollini, William G. Read, Karen H. Rosenlof, Alexei Rozanov, Christopher E. Sioris, Takafumi Sugita, Thomas von Clarmann, Kaley A. Walker, and Katja Weigel
Atmos. Meas. Tech., 16, 4589–4642, https://doi.org/10.5194/amt-16-4589-2023, https://doi.org/10.5194/amt-16-4589-2023, 2023
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We quantify biases and drifts (and their uncertainties) between the stratospheric water vapor measurement records of 15 satellite-based instruments (SATs, with 31 different retrievals) and balloon-borne frost point hygrometers (FPs) launched at 27 globally distributed stations. These comparisons of measurements during the period 2000–2016 are made using robust, consistent statistical methods. With some exceptions, the biases and drifts determined for most SAT–FP pairs are < 10 % and < 1 % yr−1.
Tim A. van Kempen, Tim J. Rotmans, Richard M. van Hees, Carol Bruegge, Dejian Fu, Ruud Hoogeveen, Thomas J. Pongetti, Robert Rosenberg, and Ilse Aben
Atmos. Meas. Tech., 16, 4507–4527, https://doi.org/10.5194/amt-16-4507-2023, https://doi.org/10.5194/amt-16-4507-2023, 2023
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Validation of satellite measurements is essential for providing reliable and consistent products. In this paper, a validation method for TROPOMI-SWIR (Tropospheric Measurement Instrument in the short-wavelength infrared) is explored. TROPOMI-SWIR has been shown to be exceptionally stable, a necessity to explore the methodology. Railroad Valley, Nevada, is a prime location to perform the necessary measurements to validate the satellite measurements of TROPOMI-SWIR.
Serin Kim, Daewon Kim, Hyunkee Hong, Lim-Seok Chang, Hanlim Lee, Deok-Rae Kim, Donghee Kim, Jeong-Ah Yu, Dongwon Lee, Ukkyo Jeong, Chang-Kuen Song, Sang-Woo Kim, Sang Seo Park, Jhoon Kim, Thomas F. Hanisco, Junsung Park, Wonei Choi, and Kwangyul Lee
Atmos. Meas. Tech., 16, 3959–3972, https://doi.org/10.5194/amt-16-3959-2023, https://doi.org/10.5194/amt-16-3959-2023, 2023
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A first evaluation of the Geostationary Environmental Monitoring Spectrometer (GEMS) NO2 was carried out via comparison with the NO2 data obtained from the ground-based Pandora direct-sun measurements at four sites in Seosan, Republic of Korea. Comparisons between GEMS NO2 and Pandora NO2 were performed according to GEMS cloud fraction. GEMS NO2 showed good agreement with that of Pandora NO2 under less cloudy conditions.
Nicholas Balasus, Daniel J. Jacob, Alba Lorente, Joannes D. Maasakkers, Robert J. Parker, Hartmut Boesch, Zichong Chen, Makoto M. Kelp, Hannah Nesser, and Daniel J. Varon
Atmos. Meas. Tech., 16, 3787–3807, https://doi.org/10.5194/amt-16-3787-2023, https://doi.org/10.5194/amt-16-3787-2023, 2023
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We use machine learning to remove biases in TROPOMI satellite observations of atmospheric methane, with GOSAT observations serving as a reference. We find that the TROPOMI biases relative to GOSAT are related to the presence of aerosols and clouds, the surface brightness, and the specific detector that makes the observation aboard TROPOMI. The resulting blended TROPOMI+GOSAT product is more reliable for quantifying methane emissions.
Thomas E. Taylor, Christopher W. O'Dell, David Baker, Carol Bruegge, Albert Chang, Lars Chapsky, Abhishek Chatterjee, Cecilia Cheng, Frédéric Chevallier, David Crisp, Lan Dang, Brian Drouin, Annmarie Eldering, Liang Feng, Brendan Fisher, Dejian Fu, Michael Gunson, Vance Haemmerle, Graziela R. Keller, Matthäus Kiel, Le Kuai, Thomas Kurosu, Alyn Lambert, Joshua Laughner, Richard Lee, Junjie Liu, Lucas Mandrake, Yuliya Marchetti, Gregory McGarragh, Aronne Merrelli, Robert R. Nelson, Greg Osterman, Fabiano Oyafuso, Paul I. Palmer, Vivienne H. Payne, Robert Rosenberg, Peter Somkuti, Gary Spiers, Cathy To, Brad Weir, Paul O. Wennberg, Shanshan Yu, and Jia Zong
Atmos. Meas. Tech., 16, 3173–3209, https://doi.org/10.5194/amt-16-3173-2023, https://doi.org/10.5194/amt-16-3173-2023, 2023
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NASA's Orbiting Carbon Observatory 2 and 3 (OCO-2 and OCO-3, respectively) provide complementary spatiotemporal coverage from a sun-synchronous and precession orbit, respectively. Estimates of total column carbon dioxide (XCO2) derived from the two sensors using the same retrieval algorithm show broad consistency over a 2.5-year overlapping time record. This suggests that data from the two satellites may be used together for scientific analysis.
Lena Katharina Jänicke, Rene Preusker, Marco Celesti, Marin Tudoroiu, Jürgen Fischer, Dirk Schüttemeyer, and Matthias Drusch
Atmos. Meas. Tech., 16, 3101–3121, https://doi.org/10.5194/amt-16-3101-2023, https://doi.org/10.5194/amt-16-3101-2023, 2023
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To compare two top-of-atmosphere radiances measured by instruments with different spectral characteristics, a transfer function has been developed. It is applied to a tandem data set of Sentinel-3A and B, for which OLCI-B mimicked the ESA’s eighth Earth Explorer FLEX. We found that OLCI-A measured radiances about 2 % brighter than OLCI-FLEX. Only at larger wavelengths were OLCI-A measurements about 5 % darker. The method is thus successful, being sensitive to calibration and processing issues.
Luis F. Millán, Gloria L. Manney, Harald Boenisch, Michaela I. Hegglin, Peter Hoor, Daniel Kunkel, Thierry Leblanc, Irina Petropavlovskikh, Kaley Walker, Krzysztof Wargan, and Andreas Zahn
Atmos. Meas. Tech., 16, 2957–2988, https://doi.org/10.5194/amt-16-2957-2023, https://doi.org/10.5194/amt-16-2957-2023, 2023
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The determination of atmospheric composition trends in the upper troposphere and lower stratosphere (UTLS) is still highly uncertain. We present the creation of dynamical diagnostics to map several ozone datasets (ozonesondes, lidars, aircraft, and satellite measurements) in geophysically based coordinate systems. The diagnostics can also be used to analyze other greenhouse gases relevant to surface climate and UTLS chemistry.
Zhihua Zhang, Jianguo Niu, Lawrence E. Flynn, Eric Beach, and Trevor Beck
Atmos. Meas. Tech., 16, 2919–2941, https://doi.org/10.5194/amt-16-2919-2023, https://doi.org/10.5194/amt-16-2919-2023, 2023
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This study mainly focused on addressing stability and improvement when using a broadband approach, establishing soft-calibration adjustments for both OMPS S-NPP and N20, analyzing error biases based on multi-sensor bias correction, and comparing total column ozone and aerosol index retrievals from NOAA OMPS with those from other products.
Matthew S. Johnson, Amir H. Souri, Sajeev Philip, Rajesh Kumar, Aaron Naeger, Jeffrey Geddes, Laura Judd, Scott Janz, Heesung Chong, and John Sullivan
Atmos. Meas. Tech., 16, 2431–2454, https://doi.org/10.5194/amt-16-2431-2023, https://doi.org/10.5194/amt-16-2431-2023, 2023
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Satellites provide vital information for studying the processes controlling ozone formation. Based on the abundance of particular gases in the atmosphere, ozone formation is sensitive to specific human-induced and natural emission sources. However, errors and biases in satellite retrievals hinder this data source’s application for studying ozone formation sensitivity. We conducted a thorough statistical evaluation of two commonly applied satellites for investigating ozone formation sensitivity.
Kezia Lange, Andreas Richter, Anja Schönhardt, Andreas C. Meier, Tim Bösch, André Seyler, Kai Krause, Lisa K. Behrens, Folkard Wittrock, Alexis Merlaud, Frederik Tack, Caroline Fayt, Martina M. Friedrich, Ermioni Dimitropoulou, Michel Van Roozendael, Vinod Kumar, Sebastian Donner, Steffen Dörner, Bianca Lauster, Maria Razi, Christian Borger, Katharina Uhlmannsiek, Thomas Wagner, Thomas Ruhtz, Henk Eskes, Birger Bohn, Daniel Santana Diaz, Nader Abuhassan, Dirk Schüttemeyer, and John P. Burrows
Atmos. Meas. Tech., 16, 1357–1389, https://doi.org/10.5194/amt-16-1357-2023, https://doi.org/10.5194/amt-16-1357-2023, 2023
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We present airborne imaging DOAS and ground-based stationary and car DOAS measurements conducted during the S5P-VAL-DE-Ruhr campaign in the Rhine-Ruhr region. The measurements are used to validate spaceborne NO2 data products from the Sentinel-5 Precursor TROPOspheric Monitoring Instrument (TROPOMI). Auxiliary data of the TROPOMI NO2 retrieval, such as spatially higher resolved a priori NO2 vertical profiles, surface reflectivity, and cloud treatment are investigated to evaluate their impact.
Yolanda Maria Lemes, Christoph Häni, Jesper Nørlem Kamp, and Anders Feilberg
Atmos. Meas. Tech., 16, 1295–1309, https://doi.org/10.5194/amt-16-1295-2023, https://doi.org/10.5194/amt-16-1295-2023, 2023
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The implementation of a new method, line-averaged concentration measurement with a closed-path analyzer, will enable the measurement of fluxes of multiple gases from different types of sources and will evaluate the effects of mitigation strategies on emissions. In addition, this method allows for continuous online measurements that resolve temporal variation in ammonia emissions and the peak emissions of methane.
Prajjwal Rawat, Manish Naja, Evan Fishbein, Pradeep K. Thapliyal, Rajesh Kumar, Piyush Bhardwaj, Aditya Jaiswal, Sugriva N. Tiwari, Sethuraman Venkataramani, and Shyam Lal
Atmos. Meas. Tech., 16, 889–909, https://doi.org/10.5194/amt-16-889-2023, https://doi.org/10.5194/amt-16-889-2023, 2023
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Satellite-based ozone observations have gained importance due to their global coverage. However, satellite-retrieved products are indirect and need to be validated, particularly over mountains. Ozonesondes launched from a Himalayan site are used to assess the Atmospheric Infrared Sounder (AIRS) ozone retrieval. AIRS is shown to overestimate ozone in the upper troposphere and lower stratosphere, while the differences from ozonesondes are more minor in the middle troposphere and stratosphere.
Murali Natarajan, Robert Damadeo, and David Flittner
Atmos. Meas. Tech., 16, 75–87, https://doi.org/10.5194/amt-16-75-2023, https://doi.org/10.5194/amt-16-75-2023, 2023
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Photochemically induced changes in mesospheric O3 concentration at twilight can cause asymmetry in the distribution along the line of sight of solar occultation observations that must be considered in the retrieval algorithm. Correction factors developed from diurnal photochemical model simulations were used to modify the archived SAGE III/ISS mesospheric O3 concentrations. For June 2021 the bias caused by the neglect of diurnal variations is over 30% at 64 km altitude and low latitudes.
Cited articles
Abbot, D. S., Palmer, P. I., Martin, R. V., Chance, K. V., Jacob, D. J., and Guenther, A.: Seasonal and interannual variability of North American isoprene emissions as determined by formaldehyde column measurements from space, Geophys. Res. Lett., 30, 5-1–5-4, https://doi.org/10.1029/2003GL017336, 2003.
Aliwell, S. R., Van Roozendael, M., Johnston, P. V., Richter, A., Wagner, T., Arlander, D. W., Burrows, J. P., Fish, D. J., Jones, R. L., Tørnkvist, K. K., Lambert, J., Pfeilsticker, K., and Pundt, I.: Analysis for BrO in zenith-sky spectra: An intercomparison exercise for analysis improvement, J. Geophys. Res., 107, 10-1–10-20, https://doi.org/10.1029/2001JD000329, 2002.
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Barkley, M. P., Palmer, P. I., Kuhn, U., Kesselmeier, J., Chance, K., Kurosu, T. P., Martin, R. V., Helmig, D., and Guenther, A.: Net ecosystem fluxes of isoprene over tropical South America inferred from Global Ozone Monitoring Experiment (GOME) observations of HCHO columns, J. Geophys. Res., 113, D20304, https://doi.org/10.1029/2008JD009863, 2008.
Barkley, M. P., Palmer, P. I., De Smedt, I., Karl, T., Guenther, A., and Van Roozendael, M.: Regulated large-scale annual shutdown of Amazonian isoprene emissions?, Geophys. Res. Lett., 36, L04803, https://doi.org/10.1029/2008GL036843, 2009.
Barkley, M. P., Kurosu, T. P., Chance, K., De Smedt, I., Van Roozendael, M., Arneth, A., Hagberg, D., and Guenther, A.: Assessing sources of uncertainty in formaldehyde air mass factors over tropical South America: Implications for top-down isoprene emission estimates, J. Geophys. Res., 117, D13304, https://doi.org/10.1029/2011JD016827, 2012.
Barkley, M. P., De Smedt, I., Van Roozendael, M., Kurosu, T. P., Chance, K., Arneth, A., Hagberg, D., Guenther, A., Paulot, F., Marais, E., and Mao, J.: Top-down isoprene emissions over tropical South America inferred from SCIAMACHY and OMI formaldehyde columns, J. Geophys. Res., in press, 2013.
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Brauers, T., Bossmeyer, J., Dorn, H.-P., Schlosser, E., Tillmann, R., Wegener, R., and Wahner, A.: Investigation of the formaldehyde differential absorption cross section at high and low spectral resolution in the simulation chamber SAPHIR, Atmos. Chem. Phys., 7, 3579–3586, https://doi.org/10.5194/acp-7-3579-2007, 2007.
Buchwitz, M., Rozanov, V. V., and Burrows, J. P.: A near-infrared optimized DOAS method for the fast global retrieval of atmospheric CH4, CO, CO2, H2O, and N2O total column amounts from SCIAMACHY Envisat-1 nadir radiances, J. Geophys. Res., 105, 15231–15245, 2000.
Burrows, J. P., Weber, M., Buchwitz, M., Rozanov, V., Ladstätter-Wei{ß}enmayer, A., Richter, A., Debeek, R., Hoogen, R., Bramstedt, K., Eichmann, K., Eisinger, M., and Perner, D.: The Global Ozone Monitoring Experiment (GOME): Mission concept and first scientific results, J. Atmos. Sci., 56, 151–175, 1999.
Cai, Z., Liu, Y., Liu, X., Chance, K., Nowlan, C. R., Lang, R., Munro, R., and Suleiman, R.: Characterization and correction of Global Ozone Monitoring Experiment 2 ultraviolet measurements and application to ozone profile retrievals, J. Geophys. Res., 117, D07305, https://doi.org/10.1029/2011JD017096, 2012.
Caspar, C. and Chance, K.: GOME wavelength calibration using solar and atmospheric spectra, European Space Agency, (Special Publication) ESA SP, 609–612, 1997.
Chance, K.: OMI Trace Gas Algorithms, OMI Algorithm Theoretical Basis Document, Smithsonian Astrophysical Observatory, Cambridge, MA, USA, 2002.
Chance, K. and Spurr, R. J. D.: Ring effect studies: Rayleigh scattering, including molecular parameters for rotational Raman scattering, and the Fraunhofer spectrum, Appl. Optics, 36, 5224–5230, https://doi.org/10.1364/AO.36.005224, 1997.
Chance, K., Palmer, P. I., Spurr, R. J. D., Martin, R. V., Kurosu, T. P., and Jacob, D. J.: Satellite observations of formaldehyde over North America from GOME, Geophys. Res. Lett., 27, 3461–3464, 2000.
Chance, K., Kurosu, T. P., and Sioris, C. E.: Undersampling correction for array detector-based satellite spectrometers, Appl. Optics, 44, 1296–1304, https://doi.org/10.1364/AO.44.001296, 2005.
Coldewey-Egbers, M., Weber, M., Lamsal, L. N., de Beek, R., Buchwitz, M., and Burrows, J. P.: Total ozone retrieval from GOME UV spectral data using the weighting function DOAS approach, Atmos. Chem. Phys., 5, 1015–1025, https://doi.org/10.5194/acp-5-1015-2005, 2005.
Cooke, M. C., Utembe, S. R., Gorrotxategi Carbajo, P., Archibald, A. T., Orr-Ewing, A. J., Jenkin, M. E., Derwent, R. G., Lary, D. J., and Shallcross, D. E.: Impacts of formaldehyde photolysis rates on tropospheric chemistry, Atmos. Sci. Lett., 11, 33–38, https://doi.org/10.1002/asl.251, 2010.
Curci, G., Palmer, P. I., Kurosu, T. P., Chance, K., and Visconti, G.: Estimating European volatile organic compound emissions using satellite observations of formaldehyde from the Ozone Monitoring Instrument, Atmos. Chem. Phys., 10, 11501–11517, https://doi.org/10.5194/acp-10-11501-2010, 2010.
De Smedt, I.: Long-Term Global Observations of Tropospheric Formaldehyde Retrieved from Spaceborne Nadir UV Sensors, Ph.D. thesis, Universite Libre De Bruxelles, Laboratoire do Chimie Quantique et Photophysique, Facult{é} de Sciences Appliqu{é}es, 2011.
De Smedt, I., Müller, J.-F., Stavrakou, T., van der A, R., Eskes, H., and Van Roozendael, M.: Twelve years of global observations of formaldehyde in the troposphere using GOME and SCIAMACHY sensors, Atmos. Chem. Phys., 8, 4947–4963, https://doi.org/10.5194/acp-8-4947-2008, 2008.
De Smedt, I., Stavrakou, J., Müller, J.-F., Hao, N., Valks, P., Loyola, D., and Van Roozendael, M.: H2CO Columns Retrieved From GOME-2: First Scientific Results And Progress Towards The Development Of An Operational Product, in: Proceedings of the EUTMETSAT conference, 2009.
De Smedt, I., Stavrakou, T., Müller, J.-F., Van Der A, R. J., and Van Roozendael, M.: Trend detection in satellite observations of formaldehyde tropospheric columns, Geophys. Res. Lett., 37, L18808, https://doi.org/10.1029/2010GL044245, 2010.
De Smedt, I., Van Roozendael, M., Stavrakou, T., Müller, J.-F., Lerot, C., Theys, N., Valks, P., Hao, N., and van der A, R.: Improved retrieval of global tropospheric formaldehyde columns from GOME-2/MetOp-A addressing noise reduction and instrumental degradation issues, Atmos. Meas. Tech., 5, 2933–2949, https://doi.org/10.5194/amt-5-2933-2012, 2012.
EUMETSAT: GOME-2 Product Generation Statement, Tech. Rep. EPS.SYS.SPE.990011, Eumetsat, 2011.
Fayt, C., De Smedt, I., Letocart, V., Merlaud, A., Pinardi, G., and Van Roozendael, M.: QDOAS software user manual, Belgian Institute for Space Aeronomy, 1st Edn., 2011.
Fleischmann, O. C., Hartmann, M., Burrows, J. P., and Orphal, J.: New ultraviolet absorption cross-sections of BrO at atmospheric temperatures measured by time-windowing Fourier transform spectroscopy, J. Photoch. Photobiol. A-Chemistry, 168, 117–132, https://doi.org/10.1016/j.jphotochem.2004.03.026, 2004.
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Fu, T. ., Jacob, D. J., Palmer, P. I., Chance, K., Wang, Y. X., Barletta, B., Blake, D. R., Stanton, J. C., and Pilling, M. J.: Space-based formaldehyde measurements as constrains on volatile organic compound emissions in east and south Asia and implications for ozone, J. Geophys. Res., 112, D06312, https://doi.org/10.1029/2006JD007853, 2007.
Gonzi, S. and Palmer, P. I.: Vertical transport of surface fire emissions observed from space, J. Geophys. Res., 115, D02306, https://doi.org/10.1029/2009JD012053, 2010.
Gonzi, S., Palmer, P. I., Barkley, M. P., De Smedt, I., and Van Roozendael, M.: Biomass burning emission estimates inferred from satellite column measurements of HCHO: Sensitivity to co-emitted aerosol and injection height, Geophys. Res. Lett., 38, L14807, https://doi.org/10.1029/2011GL047890, 2011.
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K{ü}hl, S., Wilms-Grabe, W., Frankenberg, C., Grzegorski, M., Platt, U., and Wagner, T.: Comparison of OClO nadir measurements from SCIAMACHY and GOME, Adv. Space Res., 37, 2247–2253, https://doi.org/10.1016/j.asr.2005.06.061, 2006.
Kurosu, T. P., Chance, K., and Sioris, C. E.: Preliminary results for HCHO and BrO from the EOS-aura ozone monitoring instrument, in: Proceedings of SPIE – The International Society for Optical Engineering, 5652, 116–123, 2004.
Lee, C., Richter, A., Weber, M., and Burrows, J. P.: SO2 Retrieval from SCIAMACHY using the Weighting Function DOAS (WFDOAS) technique: comparison with Standard DOAS retrieval, Atmos. Chem. Phys., 8, 6137–6145, https://doi.org/10.5194/acp-8-6137-2008, 2008.
Liu, X., Chance, K., Sioris, C. E., and Kurosu, T. P.: Impact of using different ozone cross sections on ozone profile retrievals from Global Ozone Monitoring Experiment (GOME) ultraviolet measurements, Atmos. Chem. Phys., 7, 3571–3578, https://doi.org/10.5194/acp-7-3571-2007, 2007.
Loyola, D., Valks, P., Hao, N., Rix, M., and Slijkhuis, S.: Algorithm Theoretical Basis Document for GOME-2 Total Column Products of Ozone, NO2, tropospheric NO2, BrO, SO2, H2O, HCHO, OClO and Cloud Properties, Tech. Rep. DLR/GOME-2/ATBD/01, Eumetsat, 2011{a}.
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MacDonald, S. M., Oetjen, H., Mahajan, A. S., Whalley, L. K., Edwards, P. M., Heard, D. E., Jones, C. E., and Plane, J. M. C.: DOAS measurements of formaldehyde and glyoxal above a south-east Asian tropical rainforest, Atmos. Chem. Phys., 12, 5949–5962, https://doi.org/10.5194/acp-12-5949-2012, 2012.
Malicet, J., Daumont, D., Charbonnier, J., Parisse, C., Chakir, A., and Brion, J.: Ozone UV spectroscopy. II. Absorption cross-sections and temperature dependence, J. Atmos. Chem., 21, 263–273, https://doi.org/10.1007/BF00696758, 1995.
Marais, E. A., Jacob, D. J., Kurosu, T. P., Chance, K., Murphy, J. G., Reeves, C., Mills, G., Casadio, S., Millet, D. B., Barkley, M. P., Paulot, F., and Mao, J.: Isoprene emissions in Africa inferred from OMI observations of formaldehyde columns, Atmos. Chem. Phys., 12, 6219–6235, https://doi.org/10.5194/acp-12-6219-2012, 2012.
Marbach, T., Beirle, S., Penning de Vries, M., Liu, C., and Wagner, T.: Sources and trends of Tropospheric Formaldehyde (HCHO) Sources and trends of Tropospheric Formaldehdye (HCHO) derived from GOME-1 and -2, Living Planet Symposium, ESA, 2010.
Martin, R. V., Chance, K., Jacob, D. J., Kurosu, T. P., Spurr, R. J. D., Bucsela, E., Gleason, J. F., Palmer, P. I., Bey, I., Fiore, A. M., Li, Q., Yantosca, R. M., and Koelemeijer, R. B. A.: An improved retrieval of tropospheric nitrogen dioxide from GOME, J. Geophys. Res., 107, https://doi.org/10.1029/2001JD001027, 2002.
Meller, R. and Moortgat, G. K.: Temperature dependence of the absorption cross sections of formaldehyde between 223 and 323 K in the wavelength range 225–375 nm, J. Geophys. Res., 105, 7089–7101, https://doi.org/10.1029/1999JD901074, 2000.
Millet, D. B., Jacob, D. J., Turquety, S., Hudman, R. C., Wu, S., Fried, A., Walega, J., Heikes, B. G., Blake, D. R., Singh, H. B., Andersen, B. E., and Clarke, A. D.: Formaldehyde distribution over North America: Implications for satellite retrievals of formaldehyde columns and isoprene emission, J. Geophys. Res., 111, https://doi.org/10.1029/2005JD006853, 2006.
Millet, D. B., Jacob, D. J., Boersma, K. F., Fu, T., Kurosu, T. P., Chance, K., Heald, C. L., and Guenther, A.: Spatial distribution of isoprene emissions from North America derived from formaldehyde column measurements by the OMI satellite sensor, J. Geophys. Res., 113, D02307, https://doi.org/10.1029/2007JD008950, 2008.
Oetjen, H., Wittrock, F., Richter, A., Chipperfield, M. P., Medeke, T., Sheode, N., Sinnhuber, B.-M., Sinnhuber, M., and Burrows, J. P.: Evaluation of stratospheric chlorine chemistry for the Arctic spring 2005 using modelled and measured OClO column densities, Atmos. Chem. Phys., 11, 689–703, https://doi.org/10.5194/acp-11-689-2011, 2011.
Palmer, P. I., Jacob, D. J., Chance, K., Martin, R. V., Spurr, R. J. D., Kurosu, T. P., Bey, I., Yantosca, R., Fiore, A., and Li, Q.: Air mass factor formulation for spectroscopic measurements from satellites: Application to formaldehyde retrievals from the Global Ozone Monitoring Experiment, J. Geophys. Res., 106, 14539–14550, https://doi.org/10.1029/2000JD900772, 2001.
Palmer, P. I., Jacob, D. J., Fiore, A. M., Martin, R. V., Chance, K., and Kurosu, T. P.: Mapping isoprene emissions over North America using formaldehyde column observations from space, J. Geophys. Res., 108, 2-1–2-13, https://doi.org/10.1029/2002JD002153, 2003.
Palmer, P. I., Abbot, D. S., Fu, T., Jacob, D. J., Chance, K., Kurosu, T. P., Guenther, A., Wiedinmyer, C., Stanton, J. C., Pilling, M. J., Pressley, S. N., Lamb, B., and Sumner, A. L.: Quantifying the seasonal and interannual variability of North American isoprene emissions using satellite observations of the formaldehyde column, J. Geophys. Res., 111, D12315, https://doi.org/10.1029/2005JD006689, 2006.
Parrish, D. D., Ryerson, T. B., Mellqvist, J., Johansson, J., Fried, A., Richter, D., Walega, J. G., Washenfelder, R. A., de Gouw, J. A., Peischl, J., Aikin, K. C., McKeen, S. A., Frost, G. J., Fehsenfeld, F. C., and Herndon, S. C.: Primary and secondary sources of formaldehyde in urban atmospheres: Houston Texas region, Atmos. Chem. Phys., 12, 3273–3288, https://doi.org/10.5194/acp-12-3273-2012, 2012.
Richter, A. and Burrows, J. P.: Tropospheric NO2 from GOME measurements, Adv. Space Res., 29, 1673–1683, https://doi.org/10.1016/S0273-1177(02)00100-X, 2002.
Richter, A., Begoin, M., Hilboll, A., and Burrows, J. P.: An improved NO2 retrieval for the GOME-2 satellite instrument, Atmos. Meas. Tech., 4, 1147–1159, https://doi.org/10.5194/amt-4-1147-2011, 2011.
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