Articles | Volume 16, issue 17
https://doi.org/10.5194/amt-16-3987-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-16-3987-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
05 Sep 2023
Research article |
| 05 Sep 2023
| 05 Sep 2023
A retrieval of xCO2 from ground-based mid-infrared NDACC solar absorption spectra and comparison to TCCON
Rafaella Chiarella
CORRESPONDING AUTHOR
Institute of Environmental Physics, University of Bremen, Bremen, Germany
Matthias Buschmann
Institute of Environmental Physics, University of Bremen, Bremen, Germany
Joshua Laughner
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
Isamu Morino
Earth system Division, National Institute for Environmental Studies (NIES), Onogawa 16-2, Tsukuba, Ibaraki 305-8506, Japan
Justus Notholt
Institute of Environmental Physics, University of Bremen, Bremen, Germany
Christof Petri
Institute of Environmental Physics, University of Bremen, Bremen, Germany
Geoffrey Toon
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
Voltaire A. Velazco
School of Earth Atmospheric and Life Sciences, University of
Wollongong, Wollongong, NSW 2522, Australia
now at: Deutscher Wetterdienst (DWD), Meteorological Observatory, 82383 Hohenpeissenberg, Germany
Thorsten Warneke
Institute of Environmental Physics, University of Bremen, Bremen, Germany
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Xiaoyi Zhao, Vitali Fioletov, Irina Petropavlovskikh, Voltaire Velazco, Alberto Redondas, Anna Solomatnikova, Corinne Vigouroux, Kimberly Strong, Michel Van Roozendael, Andrea Pazmino, Thomas F. Hanisco, Alexander Cede, Martin Tiefengraber, Gordon Labow, Masatomo Fujiwara, Ronald van der A, Debora Griffin, Chris McLinden, Tom Kralidis, Wolfgang Steinbrecht, and Sum Chi Lee
Atmos. Chem. Phys., 26, 13693–13720, https://doi.org/10.5194/acp-26-13693-2026, https://doi.org/10.5194/acp-26-13693-2026, 2026
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Total column ozone (TCO) records from six ground-based networks are compiled and evaluated using multiple satellites and reanalysis data. Station performance (1940–2024) is assessed using harmonized metrics. Ground-based annual means agree within ±2 %, while pre-satellite reanalyses show larger biases (up to −5 %). The resulting quality-assessed dataset supports trend analysis and satellite validation.
Alexander Polle, Lukas Grosch, Alexandros Panagiotis Poulidis, Mihalis Vrekoussis, and Thorsten Warneke
EGUsphere, https://doi.org/10.5194/egusphere-2026-5393, https://doi.org/10.5194/egusphere-2026-5393, 2026
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
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We estimated horizontal wind from the hover tilt of a DJI Air 3S without adding a wind sensor. Across 50 near-surface sessions, a model trained against a nearby wind sensor had errors of 0.32 metres per second for speed and 7.0 degrees for direction. A calibration-flight method was less accurate overall, but gave similar speed accuracy in the six strongest-wind sessions and required no wind sensor during deployment. Other aircraft, heights, and sustained stronger winds remain to be tested.
Denghui Ji, Xiaoyu Sun, and Justus Notholt
EGUsphere, https://doi.org/10.5194/egusphere-2026-5182, https://doi.org/10.5194/egusphere-2026-5182, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Saharan dust can reach the high Arctic within only a few days, but it was unclear whether such rapid transport occurs regularly. Using atmospheric models, satellite observations, and 21 years of air-mass trajectories, we identify a recurrent pathway across the North Atlantic. This pathway becomes increasingly important at higher Arctic latitudes and efficiently carries large dust particles northward, with potential consequences for Arctic clouds and climate.
Fenjuan Wang, Shamil Maksyutov, Rajesh Janardanan, Dmitry A. Belikov, Prabir K. Patra, Ruosi Liang, Yuzhong Zhang, Ge Ren, Hong Lin, Nicole Montenegro, Antoine Berchet, Marielle Saunois, Adrien Martinez, Sara Hyvärinen, Aki Tsuruta, Samuel Takele Kenea, Miao Liang, Xin Lan, Yukio Terao, M. Kawser Ahmed, Manish Naja, Akihiko Ito, Isamu Morino, Yukio Yoshida, Yu Someya, Tazu Saeki, and Tsuneo Matsunaga
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2026-420, https://doi.org/10.5194/essd-2026-420, 2026
Preprint under review for ESSD
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Methane is a potent greenhouse gas driving climate change, yet Asian emissions remain highly uncertain. We conducted the first Methane Inversion inter-Comparison for Asia (MICA) combining seven models to estimate methane across Asia from 2010 to 2021 using satellite and ground data. We found that emissions are generally lower than prior inventories, though some countries underreport. This study provides a comprehensive, transparent dataset to quantify regional methane budgets across Asia.
Makoto Saito, Yosuke Niwa, Yukio Yoshida, Hiroshi Suto, Kei Shiomi, Akihide Kamei, Fumie Kataoka, Isamu Morino, Hibiki M. Noda, Hirofumi Ohyama, Tazu Saeki, Yu Someya, Hisashi Yashiro, and Tsuneo Matsunaga
Earth Syst. Sci. Data, 18, 6565–6588, https://doi.org/10.5194/essd-18-6565-2026, https://doi.org/10.5194/essd-18-6565-2026, 2026
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This study evaluates the ability of the GOSAT‑2 satellite to observe atmospheric methane and estimate global emissions. Using a global analysis, we show that GOSAT‑2 provides wider coverage than earlier missions and produces emission estimates consistent with independent references. The results demonstrate that satellite data offer useful information on methane sources, especially in regions with few ground measurements.
Hayoung Park, Sujong Jeong, Jaewon Joo, Dong Yeong Chang, Yu-Ri Lee, Hyuckjae Lee, Jueun Kim, Jaewon Shin, Jonghyuk Lee, Jaemin Hong, Jae Hyun Lim, Donghee Kim, Isamu Morino, Matthias M. Frey, Gwangju Moon, Hyojin Eom, Sumin Kim, Sunran Lee, Jungho Yu, and Kyucheol Shin
EGUsphere, https://doi.org/10.5194/egusphere-2026-3755, https://doi.org/10.5194/egusphere-2026-3755, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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This study analyzed greenhouse gas emissions from one of South Korea’s largest petrochemical complexes using ground, mobile, aircraft, and satellite measurements. The results revealed higher emissions, including methane leaks, than what was reported in existing inventory estimates. By integrating different types of observations, this study shows a more accurate way to measure industrial emissions and provides information that can support better emissions reporting and climate action.
Robert J. Parker, Michael P. Cartwright, Dan Orr, Lakshmi N. Bharathan, Neil Humpage, Alex J. Webb, Peter Somkuti, Hartmut Boesch, Antonio Di Noia, Hiroshi Suto, Matthias Buschmann, Nicholas M. Deutscher, David W. T. Griffith, Frank Hase, Rigel Kivi, Erin McGee, Isamu Morino, Hirofumi Ohyama, Christof Petri, John Robinson, Coleen M. Roehl, Mahesh Kumar Sha, Kei Shiomi, Kimberly Strong, Ralf Sussmann, Yao Té, Voltaire A. Velazco, Mihalis Vrekoussis, Wei Wang, Thorsten Warneke, Damien Weidmann, Debra Wunch, and Minqiang Zhou
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2026-625, https://doi.org/10.5194/essd-2026-625, 2026
Preprint under review for ESSD
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Methane is a powerful greenhouse gas and its concentration in the atmosphere is rising rapidly. We present a new record of atmospheric methane measured from space by the Japanese GOSAT-2 satellite, covering 2019 to 2025. The measurements are processed identically to those from its predecessor GOSAT and checked against ground-based instruments around the world. Together the two satellites provide a continuous 17-year record that helps track where methane comes from and how quickly it is changing.
Laura N. Saunders, Kaley A. Walker, Gabriele P. Stiller, Piera Raspollini, Luis F. Millán, Marco Gai, Chris D. Boone, John Gille, Norbert Glatthor, Armin Kleinboehl, Anne Kleinert, Alyn Lambert, Donal Murtaugh, Patrick E. Sheese, Geoffrey C. Toon, and Gerald Wetzel
EGUsphere, https://doi.org/10.5194/egusphere-2026-4651, https://doi.org/10.5194/egusphere-2026-4651, 2026
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We present a comprehensive evaluation of nitrous oxide (N2O) measurements taken during the 2002–2024 period from five limb-viewing satellite instruments: ACE-FTS, HIRDLS, MIPAS, Aura-MLS, and SMR. Coincident measurements are compared between satellite instruments and with independent reference data from balloon-borne instruments. We show that ACE-FTS, MIPAS, and SMR constitute an excellent 23-year record of N2O measurements that could be used to create an ESA-funded merged dataset in future.
Pradeep Khatri, Hitoshi Irie, Hiroshi Kobayashi, Isamu Morino, Yoshitaka Jin, Tadahiro Hayasaka, Hironobu Iwabuchi, Tamio Takamura, and Yoshiki Takayama
EGUsphere, https://doi.org/10.5194/egusphere-2026-2943, https://doi.org/10.5194/egusphere-2026-2943, 2026
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This study investigates the spectral characteristics of zenith sky radiances under clear- and cloudy-sky conditions using SKYNET sky radiometer observations. It proposes a simple, physically interpretable method for distinguishing sky states and demonstrates that wavelength-dependent radiance information can support reliable sky-state detection across diverse atmospheric environments.
Irina Petropavlovskikh, Martine De Mazière, Anne M. Thompson, Jeannette D. Wild, James W. Hannigan, Henry B. Selkirk, Reem A. Hannun, Wolfgang Steinbrecht, Jean-Christopher Lambert, Roeland Van Malderen, Elizabeth Asher, Raul R. Cordero, Sophie Godin-Beekmann, Daan Hubert, Sergey Khaykin, Karin Kreher, Thierry Leblanc, Emmanuel Mahieu, Eliane Maillard Barras, Glen McConville, Gerald Nedoluha, Ivan Ortega, Alberto Redondas Marrero, Gunther Seckmeyer, Ryan M. Stauffer, Sarah A. Strode, Kim Strong, Takafumi Sugita, Michel Van Roozendael, Voltaire Velazco, Corinne Vigouroux, and Bärbel Vogel
Atmos. Chem. Phys., 26, 8637–8675, https://doi.org/10.5194/acp-26-8637-2026, https://doi.org/10.5194/acp-26-8637-2026, 2026
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This introduction to the special issue "Achievements and perspectives of the Network for the Detection of Atmospheric Composition Change after 35 years of operation” provides an overview of important research findings achieved under the NDACC objectives. The future of NDACC is discussed in the light of the evolution of the scientific questions, evolving collaborations with partners and Cooperating Networks, and the current landscape of gaps in satellite and ground-based observations.
Beatriz Herrera, Enrico Dammers, Martine De Maziere, Omaira Garcia, Michel Grutter, James W. Hannigan, Dylan B. A. Jones, Nicholas Jones, Emmanuel Mahieu, Maria Makarova, Kazuyuki Miyazaki, Isamu Morino, Isao Murata, Ivan Ortega, Mathias Palm, Anatoly Poverovskii, Takashi Sekiya, Dan Smale, Hannah Sill, Wolfgang Stremme, Ralf Sussmann, Geoffrey Toon, Corinne Vigouroux, Wei Wang, Tyler Wizenberg, and Kimberly Strong
EGUsphere, https://doi.org/10.5194/egusphere-2026-3138, https://doi.org/10.5194/egusphere-2026-3138, 2026
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This work investigates how atmospheric ammonia changes over time using long-term observations and simulations at locations around the world. While its main sources are related to agriculture, wildfires, vehicles, and volcanoes also contribute. The results show that ammonia levels vary strongly during the day and across seasons, and are rising at most locations. These findings improve our understanding of air pollution and its impacts.
Frank Werner, Kevin W. Bowman, Seungwon Lee, Joshua L. Laughner, Vivienne H. Payne, and James L. McDuffie
Atmos. Meas. Tech., 19, 3095–3109, https://doi.org/10.5194/amt-19-3095-2026, https://doi.org/10.5194/amt-19-3095-2026, 2026
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We developed a hybrid machine learning-optimal estimation retrieval system that efficiently and accurately mimics operational retrieval results. Crucially, this algorithm also predicts critical diagnostic variables including observation operators needed for comparison with independent data and ingestion into downstream chemical data assimilation models.
Vincent Enders, Astrid Müller, Matthias Max Frey, Frank Hase, Ralph Kleinschek, Marvin Knapp, Benedikt Löw, Isamu Morino, Shin-Ichiro Nakaoka, Hideki Nara, Hiroshi Tanimoto, Sanam N. Vardag, Karolin Voss, and André Butz
Atmos. Meas. Tech., 19, 2633–2655, https://doi.org/10.5194/amt-19-2633-2026, https://doi.org/10.5194/amt-19-2633-2026, 2026
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We have deployed two spectrometers on a ship traveling along the coast of Japan. By that, we were able to repeatedly measure the greenhouse gas and air pollutant emissions of power plants, large industrial facilities, and cities. Using the ratios between the different gases, we are able to identify sources based on their unique signature. In addition, we are able to show that spectrometers can be operated on a ship, while still fulfilling the high standards of land-based observation networks.
Bavo Langerock, Minqiang Zhou, Martine De Mazière, Mahesh Kumar Sha, Filip Desmet, Bart Dils, Corinne Vigouroux, Rigel Kivi, Isamu Morino, Mathias Palm, Gopala Krishna Darbha, Soumik Banerjee, Sujata Ray, and Mohmmed Talib
EGUsphere, https://doi.org/10.5194/egusphere-2026-1890, https://doi.org/10.5194/egusphere-2026-1890, 2026
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
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This work describes an algorithm to correct measurements obtained from Fourier-Transform Infrared spectrometers (FTIR) for nonlinear detector response. The method is demonstrated for remote sensing observational networks for atmospheric gas products (NDACC, TCCON and COCCON). Diagnostic metrics are introduced and have the potential to characterize the cause of the underlying nonlinearity (saturation or optical misalignment). The algorithm is made available in python.
Oliver Schneising, Heinrich Bovensmann, Michael Buchwitz, Matthias Buschmann, Nicholas M. Deutscher, David W. T. Griffith, Jonas Hachmeister, Frank Hase, Laura T. Iraci, Rigel Kivi, Isamu Morino, Hirofumi Ohyama, Christof Petri, Maximilian Reuter, John Robinson, Coleen Roehl, Mahesh Kumar Sha, Kei Shiomi, Kimberly Strong, Ralf Sussmann, Yao Té, Voltaire A. Velazco, Mihalis Vrekoussis, Wei Wang, Thorsten Warneke, Damien Weidmann, Debra Wunch, Minqiang Zhou, and Hartmut Bösch
Atmos. Meas. Tech., 19, 2407–2435, https://doi.org/10.5194/amt-19-2407-2026, https://doi.org/10.5194/amt-19-2407-2026, 2026
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We present an improved version of the TROPOMI/WFMD (TROPOspheric Monitoring Instrument/Weighting Function Modified Differential) algorithm for the simultaneous retrieval of atmospheric methane and carbon monoxide from satellite observations. The updated data product combines higher data yield with better precision and accuracy, expanding its suitability for a wider range of scientific applications. These substantial advances are mainly due to refined quality filtering, enabling more reliable identification of cloudy scenes and mitigating specific aerosol-related issues.
Xiaoyu Sun, Mathias Palm, Katrin Müller, Denghui Ji, Sharon Patris, and Justus Notholt
Atmos. Chem. Phys., 26, 4841–4861, https://doi.org/10.5194/acp-26-4841-2026, https://doi.org/10.5194/acp-26-4841-2026, 2026
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Near-surface ozone over the tropical Pacific is among the lowest on Earth. This study provides rare observations from this key region. Using sunlight measurements with an infrared spectrometer in Palau, we found that ozone rises in the morning and falls after noon. This daily rhythm and very low levels show how clean ocean air and weak thunderstorms shape atmospheric chemistry and affect Earth's climate.
Nasrin Mostafavi Pak, Jonas Hachmeister, Markus Rettinger, Matthias Buschmann, Nicholas M. Deutscher, David W. T. Griffith, Laura T. Iraci, Xin Lan, Erin McGee, Isamu Morino, Dave Pollard, Coleen M. Roehl, Kimberly Strong, Rigel Kivi, and Paul Wennberg
Biogeosciences, 23, 1477–1495, https://doi.org/10.5194/bg-23-1477-2026, https://doi.org/10.5194/bg-23-1477-2026, 2026
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We studied how carbon dioxide (CO2) levels change each year using long-term measurements from twelve sites worldwide. Average growth rates from 2010 to 2024 were about 2.4 ppm/year, with notable year-to-year and regional differences. Natural climate patterns influenced these changes, while temporary shifts in human emissions, such as during COVID‑19, had modest local effects. Monitoring CO2 growth across regions helps track emissions and assess mitigation efforts.
Constantina Rousogenous, Christof Petri, Pierre-Yves Quéhé, Thomas Laemmel, Joshua L. Laughner, Maximilien Desservettaz, Michael Pikridas, Michel Ramonet, Efstratios Bourtsoukidis, Matthias Buschmann, Justus Notholt, Thorsten Warneke, Jean-Daniel Paris, Jean Sciare, and Mihalis Vrekoussis
Atmos. Meas. Tech., 19, 565–581, https://doi.org/10.5194/amt-19-565-2026, https://doi.org/10.5194/amt-19-565-2026, 2026
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The Eastern Mediterranean and Middle East is a greenhouse gas emission hotspot but lacks atmospheric monitoring. Our study introduces the first Total Carbon Column Observing Network site in this region, in Cyprus, providing high-precision columnar measurement of key greenhouse gases. This new dataset enhances global climate monitoring efforts, supports the validation of satellites, will help assess regional emission trends, filling a critical observational gap in this climate-sensitive region.
Denghui Ji, Xiaoyu Sun, Christoph Ritter, and Justus Notholt
Atmos. Meas. Tech., 19, 421–436, https://doi.org/10.5194/amt-19-421-2026, https://doi.org/10.5194/amt-19-421-2026, 2026
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We have developed a new method that uses machine learning to analyse aerosols by combining different instruments measuring at different wavelengths. This method can identify the composition of these aerosols faster and more accurately. We tested it using ground-based data. Our results show that this method can help monitor air quality and better understand the impact of aerosols on the climate.
Joshua L. Laughner, Susan S. Kulawik, and Vivienne H. Payne
Atmos. Meas. Tech., 19, 249–276, https://doi.org/10.5194/amt-19-249-2026, https://doi.org/10.5194/amt-19-249-2026, 2026
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We developed an algorithm to infer peroxyacyl nitrates from an instrument that has been in space for over 20 years. These nitrates can transport pollution significant distances downwind, thus having a long term record of their concentrations can help understand how transport of pollution changed over time. We were able to develop a product for this instrument that produces results compatible with a more recent instrument, allowing them to work together in future analyses.
Sergey Khaykin, Michaël Sicard, Thierry Leblanc, Tetsu Sakai, Nickolay Balugin, Gwenaël Berthet, Stëphane Chevrier, Fernando Chouza, Artem Feofilov, Dominique Gantois, Sophie Godin-Beekmann, Arezki Haddouche, Yoshitaka Jin, Isamu Morino, Nicolas Kadygrov, Thomas Lecas, Ben Liley, Richard Querel, Ghasssan Taha, and Vladimir Yushkov
Atmos. Chem. Phys., 26, 607–622, https://doi.org/10.5194/acp-26-607-2026, https://doi.org/10.5194/acp-26-607-2026, 2026
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In April 2024, the Ruang volcano in Indonesia sent large amounts of gas and particles high into the atmosphere, which then spread worldwide. Using the new European EarthCARE satellite and its advanced laser instrument ATLID (Atmospheric LIDar), together with ground and balloon observations, we tracked how these particles doubled levels in the tropics and spread into both hemispheres. The study shows ATLID’s power to reveal how eruptions can affect climate, clouds, and ozone for more than a year.
Jonas Hachmeister, Debra Wunch, Erin McGee, Kimberly Strong, Rigel Kivi, Justus Notholt, Thorsten Warneke, and Matthias Buschmann
Atmos. Meas. Tech., 18, 7105–7128, https://doi.org/10.5194/amt-18-7105-2025, https://doi.org/10.5194/amt-18-7105-2025, 2025
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Methane measurements from the Total Carbon Column Observing Network (TCCON) are important for climate research, especially in the Arctic, where few measurements are available. We show that during early spring systematic errors are present in these data that are correlated to the presence of the polar vortex. These errors occur due to the usage of wrong methane prior shapes in the retrieval and can be alleviated by modifying the prior shape accordingly.
Sina Voshtani, Dylan B. A. Jones, Debra Wunch, Drew C. Pendergrass, Paul O. Wennberg, David F. Pollard, Isamu Morino, Hirofumi Ohyama, Nicholas M. Deutscher, Frank Hase, Ralf Sussmann, Damien Weidmann, Rigel Kivi, Omaira García, Yao Té, Jack Chen, Kerry Anderson, Robin Stevens, Shobha Kondragunta, Aihua Zhu, Douglas Worthy, Senen Racki, Kathryn McKain, Maria V. Makarova, Nicholas Jones, Emmanuel Mahieu, Andrea Cadena-Caicedo, Paolo Cristofanelli, Casper Labuschagne, Elena Kozlova, Thomas Seitz, Martin Steinbacher, Reza Mahdi, and Isao Murata
Atmos. Chem. Phys., 25, 15527–15565, https://doi.org/10.5194/acp-25-15527-2025, https://doi.org/10.5194/acp-25-15527-2025, 2025
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We assess the complementarity of the greater temporal coverage provided by ground-based remote sensing data with the spatial coverage of satellite observations when these data are used together to quantify CO emissions from extreme wildfires in 2023. Our results reveal that the commonly used biomass burning emission inventories significantly underestimate the fire emissions and emphasize the importance of the ground-based remote sensing data in reducing uncertainties in the estimated emissions.
Andrew Gerald Barr, Jochen Landgraf, Mari Martinez-Velarte, Mihalis Vrekoussis, Ralf Sussmann, Isamu Morino, Kimberly Strong, Minqiang Zhou, Voltaire A. Velazco, Hirofumi Ohyama, Thorsten Warneke, Frank Hase, and Tobias Borsdorff
Atmos. Meas. Tech., 18, 6093–6123, https://doi.org/10.5194/amt-18-6093-2025, https://doi.org/10.5194/amt-18-6093-2025, 2025
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The Greenhouse Gases Observing Satellite-2 (GOSAT-2) is a satellite dedicated to measuring concentrations of greenhouse gases from space. Since its launch, the increase of CH4 and CO2 concentrations in the atmosphere is clear. The datasets obtained from GOSAT-2 are used in the Copernicus atmospheric services to monitor the climate, in light of the Paris Agreement. Here we present robust datasets of these gases from GOSAT-2, including a novel machine learning approach to data quality filtering.
Denghui Ji, Christoph Ritter, Xiaoyu Sun, Manuel Moser, Christiane Voigt, Mathias Palm, and Justus Notholt
Atmos. Chem. Phys., 25, 13037–13052, https://doi.org/10.5194/acp-25-13037-2025, https://doi.org/10.5194/acp-25-13037-2025, 2025
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We discovered a process where large aerosols help small water droplets in Arctic clouds grow, even when conditions normally favor ice. Unlike the traditional view, this process may explain how liquid and ice can coexist in cold clouds. Based on theory and aircraft data, our findings provide new insight into the microphysics of mixed-phase clouds, which could improve understanding of how Arctic clouds affect climate.
Roeland Van Malderen, Zhou Zang, Kai-Lan Chang, Robin Björklund, Owen R. Cooper, Jane Liu, Eliane Maillard Barras, Corinne Vigouroux, Irina Petropavlovskikh, Thierry Leblanc, Valérie Thouret, Pawel Wolff, Peter Effertz, Audrey Gaudel, David W. Tarasick, Herman G. J. Smit, Anne M. Thompson, Ryan M. Stauffer, Debra E. Kollonige, Deniz Poyraz, Gérard Ancellet, Marie-Renée De Backer, Matthias M. Frey, James W. Hannigan, José L. Hernandez, Bryan J. Johnson, Nicholas Jones, Rigel Kivi, Emmanuel Mahieu, Isamu Morino, Glen McConville, Katrin Müller, Isao Murata, Justus Notholt, Ankie Piters, Maxime Prignon, Richard Querel, Vincenzo Rizi, Dan Smale, Wolfgang Steinbrecht, Kimberly Strong, and Ralf Sussmann
Atmos. Chem. Phys., 25, 9905–9935, https://doi.org/10.5194/acp-25-9905-2025, https://doi.org/10.5194/acp-25-9905-2025, 2025
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Tropospheric ozone is an important greenhouse gas and an air pollutant whose distribution and time variability are mainly governed by anthropogenic emissions and dynamics. In this paper, we assess regional trends of tropospheric ozone column amounts, based on two different approaches of merging or synthesizing ground-based observations and their trends within specific regions. Our findings clearly demonstrate regional trend differences but also consistently higher pre-COVID than post-COVID trends.
Lukas Heizmann, Mathias Palm, Justus Notholt, and Matthias Buschmann
EGUsphere, https://doi.org/10.5194/egusphere-2025-3691, https://doi.org/10.5194/egusphere-2025-3691, 2025
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Fourier transform infrared emission spectroscopy measures the infrared radiation originating from the thermal emission of the atmosphere. The measured interferograms are transformed into spectra via Fourier transformation. The established method for calibration is strictly speaking only valid for infinitely long interferograms. We quantify the errors caused by this idealization in a case study and find that they are generally below 0.05 % in spectral regions that are of interest for retrievals.
Carley D. Fredrickson, Scott J. Janz, Lok N. Lamsal, Ursula A. Jongebloed, Joshua L. Laughner, and Joel A. Thornton
Atmos. Meas. Tech., 18, 3669–3689, https://doi.org/10.5194/amt-18-3669-2025, https://doi.org/10.5194/amt-18-3669-2025, 2025
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We present an analysis of high-resolution remote sensing measurements of nitrogen-containing trace gases emitted by wildfires. The measurements were made using an instrument on the NASA ER-2 aircraft in the summer of 2019. We find that time-resolved fire intensity is critical to quantify trace gas emissions over a fire's entire lifespan. These findings have implications for improving air pollution forecasts downwind of wildfires using computer models of atmospheric chemistry and meteorology.
Aki Tsuruta, Akihiko Kuze, Kei Shiomi, Fumie Kataoka, Nobuhiro Kikuchi, Tuula Aalto, Leif Backman, Ella Kivimäki, Maria K. Tenkanen, Kathryn McKain, Omaira E. García, Frank Hase, Rigel Kivi, Isamu Morino, Hirofumi Ohyama, David F. Pollard, Mahesh K. Sha, Kimberly Strong, Ralf Sussmann, Yao Te, Voltaire A. Velazco, Mihalis Vrekoussis, Thorsten Warneke, Minqiang Zhou, and Hiroshi Suto
Atmos. Chem. Phys., 25, 7829–7862, https://doi.org/10.5194/acp-25-7829-2025, https://doi.org/10.5194/acp-25-7829-2025, 2025
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Satellite data bring invaluable information about greenhouse gas emissions globally. We found that a new type of data from the Greenhouse Gas Observing Satellite (GOSAT), which contains information about methane in the lowest layer of Earth's atmosphere, could provide reliable estimates of recent methane emissions when combined with atmospheric modelling. Therefore, the use of such data is encouraged to improve emission quantification methods and advance our understanding of methane cycles.
Roeland Van Malderen, Anne M. Thompson, Debra E. Kollonige, Ryan M. Stauffer, Herman G. J. Smit, Eliane Maillard Barras, Corinne Vigouroux, Irina Petropavlovskikh, Thierry Leblanc, Valérie Thouret, Pawel Wolff, Peter Effertz, David W. Tarasick, Deniz Poyraz, Gérard Ancellet, Marie-Renée De Backer, Stéphanie Evan, Victoria Flood, Matthias M. Frey, James W. Hannigan, José L. Hernandez, Marco Iarlori, Bryan J. Johnson, Nicholas Jones, Rigel Kivi, Emmanuel Mahieu, Glen McConville, Katrin Müller, Tomoo Nagahama, Justus Notholt, Ankie Piters, Natalia Prats, Richard Querel, Dan Smale, Wolfgang Steinbrecht, Kimberly Strong, and Ralf Sussmann
Atmos. Chem. Phys., 25, 7187–7225, https://doi.org/10.5194/acp-25-7187-2025, https://doi.org/10.5194/acp-25-7187-2025, 2025
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Tropospheric ozone is an important greenhouse gas and is an air pollutant. The time variability of tropospheric ozone is mainly driven by anthropogenic emissions. In this paper, we study the distribution and time variability of ozone from harmonized ground-based observations from five different measurement techniques. Our findings provide clear standard references for atmospheric models and evolving tropospheric ozone satellite data for the 2000–2022 period.
Xiaoyu Sun, Katrin Müller, Mathias Palm, Christoph Ritter, Denghui Ji, Tim Balthasar Röpke, and Justus Notholt
Atmos. Chem. Phys., 25, 6881–6902, https://doi.org/10.5194/acp-25-6881-2025, https://doi.org/10.5194/acp-25-6881-2025, 2025
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We studied how air moves from the lower atmosphere to the stratosphere over the tropical western Pacific. Using observations and air tracking, we found that, in winter, air ascends and cold temperatures freeze water out, drying it before it enters the stratosphere. In summer, air tends to sink after cloud formation. This process affects water vapor amounts in the stratosphere, influencing the greenhouse effect and climate.
Denghui Ji, Mathias Palm, Matthias Buschmann, Kerstin Ebell, Marion Maturilli, Xiaoyu Sun, and Justus Notholt
Atmos. Chem. Phys., 25, 3889–3904, https://doi.org/10.5194/acp-25-3889-2025, https://doi.org/10.5194/acp-25-3889-2025, 2025
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Our study explores how certain aerosols, like sea salt, affect infrared heat radiation in the Arctic, potentially speeding up warming. We used advanced technology to measure aerosol composition and found that these particles grow with humidity, significantly increasing their heat-trapping effect in the infrared region, especially in winter. Our findings suggest these aerosols could be a key factor in Arctic warming, emphasizing the importance of understanding aerosols for climate prediction.
André Ehrlich, Susanne Crewell, Andreas Herber, Marcus Klingebiel, Christof Lüpkes, Mario Mech, Sebastian Becker, Stephan Borrmann, Heiko Bozem, Matthias Buschmann, Hans-Christian Clemen, Elena De La Torre Castro, Henning Dorff, Regis Dupuy, Oliver Eppers, Florian Ewald, Geet George, Andreas Giez, Sarah Grawe, Christophe Gourbeyre, Jörg Hartmann, Evelyn Jäkel, Philipp Joppe, Olivier Jourdan, Zsófia Jurányi, Benjamin Kirbus, Johannes Lucke, Anna E. Luebke, Maximilian Maahn, Nina Maherndl, Christian Mallaun, Johanna Mayer, Stephan Mertes, Guillaume Mioche, Manuel Moser, Hanno Müller, Veronika Pörtge, Nils Risse, Greg Roberts, Sophie Rosenburg, Johannes Röttenbacher, Michael Schäfer, Jonas Schaefer, Andreas Schäfler, Imke Schirmacher, Johannes Schneider, Sabrina Schnitt, Frank Stratmann, Christian Tatzelt, Christiane Voigt, Andreas Walbröl, Anna Weber, Bruno Wetzel, Martin Wirth, and Manfred Wendisch
Earth Syst. Sci. Data, 17, 1295–1328, https://doi.org/10.5194/essd-17-1295-2025, https://doi.org/10.5194/essd-17-1295-2025, 2025
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This paper provides an overview of the HALO–(AC)3 aircraft campaign data sets, the campaign-specific instrument operation, data processing, and data quality. The data set comprises in situ and remote sensing observations from three research aircraft: HALO, Polar 5, and Polar 6. All data are published in the PANGAEA database by instrument-separated data subsets. It is highlighted how the scientific analysis of the HALO–(AC)3 data benefits from the coordinated operation of three aircraft.
Frank Hase, Paolo Castracane, Angelika Dehn, Omaira Elena García, David W. T. Griffith, Lukas Heizmann, Nicholas B. Jones, Tomi Karppinen, Rigel Kivi, Martine de Mazière, Justus Notholt, and Mahesh Kumar Sha
Atmos. Meas. Tech., 18, 1257–1267, https://doi.org/10.5194/amt-18-1257-2025, https://doi.org/10.5194/amt-18-1257-2025, 2025
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The primary measurement result delivered by a Fourier transform spectrometer is an interferogram, and the spectrum required for further analysis needs to be calculated from the interferogram by Fourier analysis. The paper deals with technical aspects of this process and shows how the reconstruction of the spectrum can be optimized.
Jamal Makkor, Mathias Palm, Matthias Buschmann, Emmanuel Mahieu, Martyn P. Chipperfield, and Justus Notholt
Atmos. Meas. Tech., 18, 1105–1114, https://doi.org/10.5194/amt-18-1105-2025, https://doi.org/10.5194/amt-18-1105-2025, 2025
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During the years 1950 and 1951, Marcel Migeotte took regular solar measurements in the form of paper rolls at the Jungfraujoch site. These historical spectra proved to be valuable for atmospheric research and needed to be saved for posterity. Therefore, a digitization method which used image-processing techniques was developed to extract them from the historical paper rolls. This allowed them to be saved in a machine-readable format that is easily accessible to the scientific community.
Minqiang Zhou, Pucai Wang, Bart Dils, Bavo Langerock, Geoff Toon, Christian Hermans, Weidong Nan, Qun Cheng, and Martine De Mazière
Atmos. Meas. Tech., 17, 6385–6396, https://doi.org/10.5194/amt-17-6385-2024, https://doi.org/10.5194/amt-17-6385-2024, 2024
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Solar absorption spectra near 2967 cm−1 recorded by a ground-based FTIR with a high spectral resolution of 0.0035 cm-1 are applied to retrieve C3H8 columns for the first time in Xianghe, China, within the NDACC-IRWG. The mean and standard deviation of the C3H8 columns are 1.80 ± 0.81 (1σ) × 1015 molec. cm-2. Good correlations are found between C3H8 and other non-methane hydrocarbons, such as C2H6 (R = 0.84) and C2H2 (R = 0.79), as well as between C3H8 and CO (R = 0.72).
Kavitha Mottungan, Chayan Roychoudhury, Vanessa Brocchi, Benjamin Gaubert, Wenfu Tang, Mohammad Amin Mirrezaei, John McKinnon, Yafang Guo, David W. T. Griffith, Dietrich G. Feist, Isamu Morino, Mahesh K. Sha, Manvendra K. Dubey, Martine De Mazière, Nicholas M. Deutscher, Paul O. Wennberg, Ralf Sussmann, Rigel Kivi, Tae-Young Goo, Voltaire A. Velazco, Wei Wang, and Avelino F. Arellano Jr.
Atmos. Meas. Tech., 17, 5861–5885, https://doi.org/10.5194/amt-17-5861-2024, https://doi.org/10.5194/amt-17-5861-2024, 2024
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A combination of data analysis techniques is introduced to separate local and regional influences on observed levels of carbon dioxide, carbon monoxide, and methane from an established ground-based remote sensing network. We take advantage of the covariations in these trace gases to identify the dominant type of sources driving these levels. Applying these methods in conjunction with existing approaches to other datasets can better address uncertainties in identifying sources and sinks.
Christopher Chan Miller, Sébastien Roche, Jonas S. Wilzewski, Xiong Liu, Kelly Chance, Amir H. Souri, Eamon Conway, Bingkun Luo, Jenna Samra, Jacob Hawthorne, Kang Sun, Carly Staebell, Apisada Chulakadabba, Maryann Sargent, Joshua S. Benmergui, Jonathan E. Franklin, Bruce C. Daube, Yang Li, Joshua L. Laughner, Bianca C. Baier, Ritesh Gautam, Mark Omara, and Steven C. Wofsy
Atmos. Meas. Tech., 17, 5429–5454, https://doi.org/10.5194/amt-17-5429-2024, https://doi.org/10.5194/amt-17-5429-2024, 2024
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MethaneSAT is an upcoming satellite mission designed to monitor methane emissions from the oil and gas (O&G) industry globally. Here, we present observations from the first flight campaign of MethaneAIR, a MethaneSAT-like instrument mounted on an aircraft. MethaneAIR can map methane with high precision and accuracy over a typically sized oil and gas basin (~200 km2) in a single flight. This paper demonstrates the capability of the upcoming satellite to routinely track global O&G emissions.
Henk Eskes, Athanasios Tsikerdekis, Melanie Ades, Mihai Alexe, Anna Carlin Benedictow, Yasmine Bennouna, Lewis Blake, Idir Bouarar, Simon Chabrillat, Richard Engelen, Quentin Errera, Johannes Flemming, Sebastien Garrigues, Jan Griesfeller, Vincent Huijnen, Luka Ilić, Antje Inness, John Kapsomenakis, Zak Kipling, Bavo Langerock, Augustin Mortier, Mark Parrington, Isabelle Pison, Mikko Pitkänen, Samuel Remy, Andreas Richter, Anja Schoenhardt, Michael Schulz, Valerie Thouret, Thorsten Warneke, Christos Zerefos, and Vincent-Henri Peuch
Atmos. Chem. Phys., 24, 9475–9514, https://doi.org/10.5194/acp-24-9475-2024, https://doi.org/10.5194/acp-24-9475-2024, 2024
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The Copernicus Atmosphere Monitoring Service (CAMS) provides global analyses and forecasts of aerosols and trace gases in the atmosphere. On 27 June 2023 a major upgrade, Cy48R1, became operational. Comparisons with in situ, surface remote sensing, aircraft, and balloon and satellite observations show that the new CAMS system is a significant improvement. The results quantify the skill of CAMS to forecast impactful events, such as wildfires, dust storms and air pollution peaks.
Nelson Bègue, Alexandre Baron, Gisèle Krysztofiak, Gwenaël Berthet, Corinna Kloss, Fabrice Jégou, Sergey Khaykin, Marion Ranaivombola, Tristan Millet, Thierry Portafaix, Valentin Duflot, Philippe Keckhut, Hélène Vérèmes, Guillaume Payen, Mahesh Kumar Sha, Pierre-François Coheur, Cathy Clerbaux, Michaël Sicard, Tetsu Sakai, Richard Querel, Ben Liley, Dan Smale, Isamu Morino, Osamu Uchino, Tomohiro Nagai, Penny Smale, John Robinson, and Hassan Bencherif
Atmos. Chem. Phys., 24, 8031–8048, https://doi.org/10.5194/acp-24-8031-2024, https://doi.org/10.5194/acp-24-8031-2024, 2024
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During the 2020 austral summer, the pristine atmosphere of the southwest Indian Ocean basin experienced significant perturbations. Numerical models indicated that the lower-stratospheric aerosol content was influenced by the intense and persistent stratospheric aerosol layer generated during the 2019–2020 extreme Australian bushfire events. Ground-based observations at Réunion confirmed the simultaneous presence of African and Australian aerosol layers.
Hella van Asperen, Thorsten Warneke, Alessandro Carioca de Araújo, Bruce Forsberg, Sávio José Filgueiras Ferreira, Thomas Röckmann, Carina van der Veen, Sipko Bulthuis, Leonardo Ramos de Oliveira, Thiago de Lima Xavier, Jailson da Mata, Marta de Oliveira Sá, Paulo Ricardo Teixeira, Julie Andrews de França e Silva, Susan Trumbore, and Justus Notholt
Biogeosciences, 21, 3183–3199, https://doi.org/10.5194/bg-21-3183-2024, https://doi.org/10.5194/bg-21-3183-2024, 2024
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Carbon monoxide (CO) is regarded as an important indirect greenhouse gas. Soils can emit and take up CO, but, until now, uncertainty remains as to which process dominates in tropical rainforests. We present the first soil CO flux measurements from a tropical rainforest. Based on our observations, we report that tropical rainforest soils are a net source of CO. In addition, we show that valley streams and inundated areas are likely additional hot spots of CO in the ecosystem.
Fengxin Xie, Tao Ren, Changying Zhao, Yuan Wen, Yilei Gu, Minqiang Zhou, Pucai Wang, Kei Shiomi, and Isamu Morino
Atmos. Meas. Tech., 17, 3949–3967, https://doi.org/10.5194/amt-17-3949-2024, https://doi.org/10.5194/amt-17-3949-2024, 2024
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This study demonstrates a new machine learning approach to efficiently and accurately estimate atmospheric carbon dioxide levels from satellite data. Rather than using traditional complex physics-based retrieval methods, neural network models are trained on simulated data to rapidly predict CO2 concentrations directly from satellite spectral measurements.
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.
Joshua L. Laughner, Geoffrey C. Toon, Joseph Mendonca, Christof Petri, Sébastien Roche, Debra Wunch, Jean-Francois Blavier, David W. T. Griffith, Pauli Heikkinen, Ralph F. Keeling, Matthäus Kiel, Rigel Kivi, Coleen M. Roehl, Britton B. Stephens, Bianca C. Baier, Huilin Chen, Yonghoon Choi, Nicholas M. Deutscher, Joshua P. DiGangi, Jochen Gross, Benedikt Herkommer, Pascal Jeseck, Thomas Laemmel, Xin Lan, Erin McGee, Kathryn McKain, John Miller, Isamu Morino, Justus Notholt, Hirofumi Ohyama, David F. Pollard, Markus Rettinger, Haris Riris, Constantina Rousogenous, Mahesh Kumar Sha, Kei Shiomi, Kimberly Strong, Ralf Sussmann, Yao Té, Voltaire A. Velazco, Steven C. Wofsy, Minqiang Zhou, and Paul O. Wennberg
Earth Syst. Sci. Data, 16, 2197–2260, https://doi.org/10.5194/essd-16-2197-2024, https://doi.org/10.5194/essd-16-2197-2024, 2024
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This paper describes a new version, called GGG2020, of a data set containing column-integrated observations of greenhouse and related gases (including CO2, CH4, CO, and N2O) made by ground stations located around the world. Compared to the previous version (GGG2014), improvements have been made toward site-to-site consistency. This data set plays a key role in validating space-based greenhouse gas observations and in understanding the carbon cycle.
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.
Karl Voglmeier, Voltaire A. Velazco, Luca Egli, Julian Gröbner, Alberto Redondas, and Wolfgang Steinbrecht
Atmos. Meas. Tech., 17, 2277–2294, https://doi.org/10.5194/amt-17-2277-2024, https://doi.org/10.5194/amt-17-2277-2024, 2024
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Comparison between total ozone column (TOC) measurements from ground-based Dobson and Brewer spectrophotometers generally reveals seasonally varying differences of a few percent. This study recommends a new TOC retrieval approach, which effectively eliminates these seasonally varying differences by applying new ozone absorption cross sections, appropriate slit functions for the Dobson instrument, and climatological values for the effective ozone temperature.
Alexandra Klemme, Thorsten Warneke, Heinrich Bovensmann, Matthias Weigelt, Jürgen Müller, Tim Rixen, Justus Notholt, and Claus Lämmerzahl
Hydrol. Earth Syst. Sci., 28, 1527–1538, https://doi.org/10.5194/hess-28-1527-2024, https://doi.org/10.5194/hess-28-1527-2024, 2024
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Satellite data help estimate groundwater depletion, but earlier assessments missed mass loss from river sediment. In the Ganges–Brahmaputra–Meghna (GBM) river system, sediment accounts for 4 % of the depletion. Correcting for sediment in the GBM mountains reduces estimated depletion by 14 %. It's important to note that the Himalayas' uplift may offset some sediment-induced mass loss. This understanding is vital for accurate water storage trend assessments and sustainable groundwater management.
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.
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.
Katrin Müller, Jordis S. Tradowsky, Peter von der Gathen, Christoph Ritter, Sharon Patris, Justus Notholt, and Markus Rex
Atmos. Chem. Phys., 24, 2169–2193, https://doi.org/10.5194/acp-24-2169-2024, https://doi.org/10.5194/acp-24-2169-2024, 2024
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The Palau Atmospheric Observatory is introduced as an ideal site to detect changes in atmospheric composition and dynamics above the remote tropical western Pacific. We focus on the ozone sounding program from 2016–2021, including El Niño 2016. The year-round high convective activity is reflected in dominant low tropospheric ozone and high relative humidity. Their seasonal distributions are unique compared to other tropical sites and are modulated by the Intertropical Convergence Zone.
Julian Hofer, Patric Seifert, J. Ben Liley, Martin Radenz, Osamu Uchino, Isamu Morino, Tetsu Sakai, Tomohiro Nagai, and Albert Ansmann
Atmos. Chem. Phys., 24, 1265–1280, https://doi.org/10.5194/acp-24-1265-2024, https://doi.org/10.5194/acp-24-1265-2024, 2024
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An 11-year dataset of polarization lidar observations from Lauder, New Zealand / Aotearoa, was used to distinguish the thermodynamic phase of natural clouds. The cloud dataset was separated to assess the impact of air mass origin on the frequency of heterogeneous ice formation. Ice formation efficiency in clouds above Lauder was found to be lower than in the polluted Northern Hemisphere midlatitudes but higher than in very clean and pristine environments, such as Punta Arenas in southern Chile.
Victoria A. Flood, Kimberly Strong, Cynthia H. Whaley, Kaley A. Walker, Thomas Blumenstock, James W. Hannigan, Johan Mellqvist, Justus Notholt, Mathias Palm, Amelie N. Röhling, Stephen Arnold, Stephen Beagley, Rong-You Chien, Jesper Christensen, Makoto Deushi, Srdjan Dobricic, Xinyi Dong, Joshua S. Fu, Michael Gauss, Wanmin Gong, Joakim Langner, Kathy S. Law, Louis Marelle, Tatsuo Onishi, Naga Oshima, David A. Plummer, Luca Pozzoli, Jean-Christophe Raut, Manu A. Thomas, Svetlana Tsyro, and Steven Turnock
Atmos. Chem. Phys., 24, 1079–1118, https://doi.org/10.5194/acp-24-1079-2024, https://doi.org/10.5194/acp-24-1079-2024, 2024
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It is important to understand the composition of the Arctic atmosphere and how it is changing. Atmospheric models provide simulations that can inform policy. This study examines simulations of CH4, CO, and O3 by 11 models. Model performance is assessed by comparing results matched in space and time to measurements from five high-latitude ground-based infrared spectrometers. This work finds that models generally underpredict the concentrations of these gases in the Arctic troposphere.
Jonas Hachmeister, Oliver Schneising, Michael Buchwitz, John P. Burrows, Justus Notholt, and Matthias Buschmann
Atmos. Chem. Phys., 24, 577–595, https://doi.org/10.5194/acp-24-577-2024, https://doi.org/10.5194/acp-24-577-2024, 2024
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We quantified changes in atmospheric methane concentrations using satellite data and a dynamic linear model approach. We calculated global annual methane increases for the years 2019–2022, which are in good agreement with other sources. For zonal methane growth rates, we identified strong inter-hemispheric differences in 2019 and 2022. For 2022, we could attribute decreases in the global growth rate to the Northern Hemisphere, possibly related to a reduction in anthropogenic emissions.
Hirofumi Ohyama, Matthias M. Frey, Isamu Morino, Kei Shiomi, Masahide Nishihashi, Tatsuya Miyauchi, Hiroko Yamada, Makoto Saito, Masanobu Wakasa, Thomas Blumenstock, and Frank Hase
Atmos. Chem. Phys., 23, 15097–15119, https://doi.org/10.5194/acp-23-15097-2023, https://doi.org/10.5194/acp-23-15097-2023, 2023
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We conducted a field campaign for CO2 column measurements in the Tokyo metropolitan area with three ground-based Fourier transform spectrometers. The model simulations using prior CO2 fluxes were generally in good agreement with the observations. We developed an urban-scale inversion system in which spatially resolved CO2 fluxes and a scaling factor of large point source emissions were estimated. The posterior total CO2 emissions agreed with emission inventories within the posterior uncertainty.
Minqiang Zhou, Bavo Langerock, Mahesh Kumar Sha, Christian Hermans, Nicolas Kumps, Rigel Kivi, Pauli Heikkinen, Christof Petri, Justus Notholt, Huilin Chen, and Martine De Mazière
Atmos. Meas. Tech., 16, 5593–5608, https://doi.org/10.5194/amt-16-5593-2023, https://doi.org/10.5194/amt-16-5593-2023, 2023
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Atmospheric N2O and CH4 columns are successfully retrieved from low-resolution FTIR spectra recorded by a Bruker VERTEX 70. The 1-year measurements at Sodankylä show that the N2O total columns retrieved from 125HR and VERTEX 70 spectra are −0.3 ± 0.7 % with an R value of 0.93. The relative differences between the CH4 total columns retrieved from the 125HR and VERTEX spectra are 0.0 ± 0.8 % with an R value of 0.87. Such a technique can help to fill the gap in NDACC N2O and CH4 measurements.
Dien Wu, Joshua L. Laughner, Junjie Liu, Paul I. Palmer, John C. Lin, and Paul O. Wennberg
Geosci. Model Dev., 16, 6161–6185, https://doi.org/10.5194/gmd-16-6161-2023, https://doi.org/10.5194/gmd-16-6161-2023, 2023
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To balance computational expenses and chemical complexity in extracting emission signals from tropospheric NO2 columns, we propose a simplified non-linear Lagrangian chemistry transport model and assess its performance against TROPOMI v2 over power plants and cities. Using this model, we then discuss how NOx chemistry affects the relationship between NOx and CO2 emissions and how studying NO2 columns helps quantify modeled biases in wind directions and prior 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.
Xiaoyu Sun, Mathias Palm, Katrin Müller, Jonas Hachmeister, and Justus Notholt
Atmos. Chem. Phys., 23, 7075–7090, https://doi.org/10.5194/acp-23-7075-2023, https://doi.org/10.5194/acp-23-7075-2023, 2023
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The tropical western Pacific (TWP) is an active interhemispheric transport region contributing significantly to the global climate. A method to determine the chemical equator was developed by model simulations of a virtual passive tracer to analyze transport in the tropics, with a focus on the TWP region. We compare the chemical equator with tropical rain belts and wind fields and obtain a vertical pattern of interhemispheric transport processes which shows tilt structure in certain seasons.
Harrison A. Parker, Joshua L. Laughner, Geoffrey C. Toon, Debra Wunch, Coleen M. Roehl, Laura T. Iraci, James R. Podolske, Kathryn McKain, Bianca C. Baier, and Paul O. Wennberg
Atmos. Meas. Tech., 16, 2601–2625, https://doi.org/10.5194/amt-16-2601-2023, https://doi.org/10.5194/amt-16-2601-2023, 2023
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We describe a retrieval algorithm for determining limited information about the vertical distribution of carbon monoxide (CO) and carbon dioxide (CO2) from total column observations from ground-based observations. Our retrieved partial column values compare well with integrated in situ data. The average error for our retrieval is 1.51 ppb (~ 2 %) for CO and 5.09 ppm (~ 1.25 %) for CO2. We anticipate that this approach will find broad application for use in carbon cycle science.
Yifan Guan, Gretchen Keppel-Aleks, Scott C. Doney, Christof Petri, Dave Pollard, Debra Wunch, Frank Hase, Hirofumi Ohyama, Isamu Morino, Justus Notholt, Kei Shiomi, Kim Strong, Rigel Kivi, Matthias Buschmann, Nicholas Deutscher, Paul Wennberg, Ralf Sussmann, Voltaire A. Velazco, and Yao Té
Atmos. Chem. Phys., 23, 5355–5372, https://doi.org/10.5194/acp-23-5355-2023, https://doi.org/10.5194/acp-23-5355-2023, 2023
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We characterize spatial–temporal patterns of interannual variability (IAV) in atmospheric CO2 based on NASA’s Orbiting Carbon Observatory-2 (OCO-2). CO2 variation is strongly impacted by climate events, with higher anomalies during El Nino years. We show high correlation in IAV between space-based and ground-based CO2 from long-term sites. Because OCO-2 has near-global coverage, our paper provides a roadmap to study IAV where in situ observation is sparse, such as open oceans and remote lands.
Antonio G. Bruno, Jeremy J. Harrison, Martyn P. Chipperfield, David P. Moore, Richard J. Pope, Christopher Wilson, Emmanuel Mahieu, and Justus Notholt
Atmos. Chem. Phys., 23, 4849–4861, https://doi.org/10.5194/acp-23-4849-2023, https://doi.org/10.5194/acp-23-4849-2023, 2023
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A 3-D chemical transport model, TOMCAT; satellite data; and ground-based observations have been used to investigate hydrogen cyanide (HCN) variability. We found that the oxidation by O(1D) drives the HCN loss in the middle stratosphere and the currently JPL-recommended OH reaction rate overestimates HCN atmospheric loss. We also evaluated two different ocean uptake schemes. We found them to be unrealistic, and we need to scale these schemes to obtain good agreement with HCN observations.
Denghui Ji, Mathias Palm, Christoph Ritter, Philipp Richter, Xiaoyu Sun, Matthias Buschmann, and Justus Notholt
Atmos. Meas. Tech., 16, 1865–1879, https://doi.org/10.5194/amt-16-1865-2023, https://doi.org/10.5194/amt-16-1865-2023, 2023
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To measuring aerosol components, a Fourier transform infrared spectrometer (FTIS) and a lidar are operated in Ny-Ålesund, Spitsbergen (78° N, 11° E). Using the FTIS, a retrieval algorithm is developed for dust, sea salt, black carbon, and sulfate. The distribution of aerosols or clouds is provided by lidar and used as an indicator for aerosol or cloud retrieval with the FTS. Thus, a two-instrument joint-observation scheme is designed and is used on the data measured from 2019 to the present.
Yu Someya, Yukio Yoshida, Hirofumi Ohyama, Shohei Nomura, Akihide Kamei, Isamu Morino, Hitoshi Mukai, Tsuneo Matsunaga, Joshua L. Laughner, Voltaire A. Velazco, Benedikt Herkommer, Yao Té, Mahesh Kumar Sha, Rigel Kivi, Minqiang Zhou, Young Suk Oh, Nicholas M. Deutscher, and David W. T. Griffith
Atmos. Meas. Tech., 16, 1477–1501, https://doi.org/10.5194/amt-16-1477-2023, https://doi.org/10.5194/amt-16-1477-2023, 2023
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The updated retrieval algorithm for the Greenhouse gases Observing SATellite level 2 product is presented. The main changes in the algorithm from the previous one are the treatment of cirrus clouds, the degradation model of the sensor, solar irradiance, and gas absorption coefficient tables. The retrieval results showed improvements in fitting accuracy and an increase in the data amount over land. On the other hand, there are still large biases of XCO2 which should be corrected over the ocean.
Cameron G. MacDonald, Jon-Paul Mastrogiacomo, Joshua L. Laughner, Jacob K. Hedelius, Ray Nassar, and Debra Wunch
Atmos. Chem. Phys., 23, 3493–3516, https://doi.org/10.5194/acp-23-3493-2023, https://doi.org/10.5194/acp-23-3493-2023, 2023
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We use three satellites measuring carbon dioxide (CO2), carbon monoxide (CO) and nitrogen dioxide (NO2) to calculate atmospheric enhancements of these gases from 27 urban areas. We calculate enhancement ratios between the species and compare those to ratios derived from four globally gridded anthropogenic emission inventories. We find that the global inventories generally underestimate CO emissions in many North American and European cities relative to our observed enhancement ratios.
Nasrin Mostafavi Pak, Jacob K. Hedelius, Sébastien Roche, Liz Cunningham, Bianca Baier, Colm Sweeney, Coleen Roehl, Joshua Laughner, Geoffrey Toon, Paul Wennberg, Harrison Parker, Colin Arrowsmith, Joseph Mendonca, Pierre Fogal, Tyler Wizenberg, Beatriz Herrera, Kimberly Strong, Kaley A. Walker, Felix Vogel, and Debra Wunch
Atmos. Meas. Tech., 16, 1239–1261, https://doi.org/10.5194/amt-16-1239-2023, https://doi.org/10.5194/amt-16-1239-2023, 2023
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Ground-based remote sensing instruments in the Total Carbon Column Observing Network (TCCON) measure greenhouse gases in the atmosphere. Consistency between TCCON measurements is crucial to accurately infer changes in atmospheric composition. We use portable remote sensing instruments (EM27/SUN) to evaluate biases between TCCON stations in North America. We also improve the retrievals of EM27/SUN instruments and evaluate the previous (GGG2014) and newest (GGG2020) retrieval algorithms.
Joshua L. Laughner, Sébastien Roche, Matthäus Kiel, Geoffrey C. Toon, Debra Wunch, Bianca C. Baier, Sébastien Biraud, Huilin Chen, Rigel Kivi, Thomas Laemmel, Kathryn McKain, Pierre-Yves Quéhé, Constantina Rousogenous, Britton B. Stephens, Kaley Walker, and Paul O. Wennberg
Atmos. Meas. Tech., 16, 1121–1146, https://doi.org/10.5194/amt-16-1121-2023, https://doi.org/10.5194/amt-16-1121-2023, 2023
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Observations using sunlight to measure surface-to-space total column of greenhouse gases in the atmosphere need an initial guess of the vertical distribution of those gases to start from. We have developed an approach to provide those initial guess profiles that uses readily available meteorological data as input. This lets us make these guesses without simulating them with a global model. The profiles generated this way match independent observations well.
Brendan Byrne, David F. Baker, Sourish Basu, Michael Bertolacci, Kevin W. Bowman, Dustin Carroll, Abhishek Chatterjee, Frédéric Chevallier, Philippe Ciais, Noel Cressie, David Crisp, Sean Crowell, Feng Deng, Zhu Deng, Nicholas M. Deutscher, Manvendra K. Dubey, Sha Feng, Omaira E. García, David W. T. Griffith, Benedikt Herkommer, Lei Hu, Andrew R. Jacobson, Rajesh Janardanan, Sujong Jeong, Matthew S. Johnson, Dylan B. A. Jones, Rigel Kivi, Junjie Liu, Zhiqiang Liu, Shamil Maksyutov, John B. Miller, Scot M. Miller, Isamu Morino, Justus Notholt, Tomohiro Oda, Christopher W. O'Dell, Young-Suk Oh, Hirofumi Ohyama, Prabir K. Patra, Hélène Peiro, Christof Petri, Sajeev Philip, David F. Pollard, Benjamin Poulter, Marine Remaud, Andrew Schuh, Mahesh K. Sha, Kei Shiomi, Kimberly Strong, Colm Sweeney, Yao Té, Hanqin Tian, Voltaire A. Velazco, Mihalis Vrekoussis, Thorsten Warneke, John R. Worden, Debra Wunch, Yuanzhi Yao, Jeongmin Yun, Andrew Zammit-Mangion, and Ning Zeng
Earth Syst. Sci. Data, 15, 963–1004, https://doi.org/10.5194/essd-15-963-2023, https://doi.org/10.5194/essd-15-963-2023, 2023
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Changes in the carbon stocks of terrestrial ecosystems result in emissions and removals of CO2. These can be driven by anthropogenic activities (e.g., deforestation), natural processes (e.g., fires) or in response to rising CO2 (e.g., CO2 fertilization). This paper describes a dataset of CO2 emissions and removals derived from atmospheric CO2 observations. This pilot dataset informs current capabilities and future developments towards top-down monitoring and verification systems.
Oliver Schneising, Michael Buchwitz, Jonas Hachmeister, Steffen Vanselow, Maximilian Reuter, Matthias Buschmann, Heinrich Bovensmann, and John P. Burrows
Atmos. Meas. Tech., 16, 669–694, https://doi.org/10.5194/amt-16-669-2023, https://doi.org/10.5194/amt-16-669-2023, 2023
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Methane and carbon monoxide are important constituents of the atmosphere in the context of climate change and air pollution. We present the latest advances in the TROPOMI/WFMD algorithm to simultaneously retrieve atmospheric methane and carbon monoxide abundances from space. The changes in the latest product version are described in detail, and the resulting improvements are demonstrated. An overview of the products is provided including a discussion of annual increases and validation results.
Hao Yin, Youwen Sun, Justus Notholt, Mathias Palm, Chunxiang Ye, and Cheng Liu
Atmos. Chem. Phys., 22, 14401–14419, https://doi.org/10.5194/acp-22-14401-2022, https://doi.org/10.5194/acp-22-14401-2022, 2022
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Improved knowledge of the chemistry and drivers of surface ozone over the Qinghai-Tibet Plateau (QTP) is significant for regulatory and control purposes in this high-altitude region in the Himalayas. Our study investigates the processes and drivers of surface ozone anomalies by using machine-learning model-based meteorological normalization methods between 2015 and 2020 in urban areas over the QTP. This study can provide valuable implication for ozone mitigation over the QTP.
Youwen Sun, Hao Yin, Wei Wang, Changgong Shan, Justus Notholt, Mathias Palm, Ke Liu, Zhenyi Chen, and Cheng Liu
Atmos. Meas. Tech., 15, 4819–4834, https://doi.org/10.5194/amt-15-4819-2022, https://doi.org/10.5194/amt-15-4819-2022, 2022
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This study summarizes an overview of the status and perspective of GHG monitoring in China. This study not only improves our understanding with respect to the status, advances, and challenges of GHG monitoring in China but also presents an outlook for further improving GHG monitoring capacity in China.
Matthias Schneider, Benjamin Ertl, Qiansi Tu, Christopher J. Diekmann, Farahnaz Khosrawi, Amelie N. Röhling, Frank Hase, Darko Dubravica, Omaira E. García, Eliezer Sepúlveda, Tobias Borsdorff, Jochen Landgraf, Alba Lorente, André Butz, Huilin Chen, Rigel Kivi, Thomas Laemmel, Michel Ramonet, Cyril Crevoisier, Jérome Pernin, Martin Steinbacher, Frank Meinhardt, Kimberly Strong, Debra Wunch, Thorsten Warneke, Coleen Roehl, Paul O. Wennberg, Isamu Morino, Laura T. Iraci, Kei Shiomi, Nicholas M. Deutscher, David W. T. Griffith, Voltaire A. Velazco, and David F. Pollard
Atmos. Meas. Tech., 15, 4339–4371, https://doi.org/10.5194/amt-15-4339-2022, https://doi.org/10.5194/amt-15-4339-2022, 2022
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We present a computationally very efficient method for the synergetic use of level 2 remote-sensing data products. We apply the method to IASI vertical profile and TROPOMI total column space-borne methane observations and thus gain sensitivity for the tropospheric methane partial columns, which is not achievable by the individual use of TROPOMI and IASI. These synergetic effects are evaluated theoretically and empirically by inter-comparisons to independent references of TCCON, AirCore, and GAW.
Jonas Hachmeister, Oliver Schneising, Michael Buchwitz, Alba Lorente, Tobias Borsdorff, John P. Burrows, Justus Notholt, and Matthias Buschmann
Atmos. Meas. Tech., 15, 4063–4074, https://doi.org/10.5194/amt-15-4063-2022, https://doi.org/10.5194/amt-15-4063-2022, 2022
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Sentinel-5P trace gas retrievals rely on elevation data in their calculations. Outdated or inaccurate data can lead to significant errors in e.g. dry-air mole fractions of methane (XCH4). We show that the use of inadequate elevation data leads to strong XCH4 anomalies in Greenland. Similar problems can be expected for other regions with inaccurate elevation data. However, we expect these to be more localized. We show that updating elevation data used in the retrieval solves this issue.
Philipp Richter, Mathias Palm, Christine Weinzierl, Hannes Griesche, Penny M. Rowe, and Justus Notholt
Earth Syst. Sci. Data, 14, 2767–2784, https://doi.org/10.5194/essd-14-2767-2022, https://doi.org/10.5194/essd-14-2767-2022, 2022
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We present a dataset of cloud optical depths, effective radii and water paths from optically thin clouds observed in the Arctic around Svalbard. The data have been retrieved from infrared spectral radiance measured using a Fourier-transform infrared (FTIR) spectrometer. Besides a description of the measurements and retrieval technique, the data are put into context with results of corresponding measurements from microwave radiometer, lidar and cloud radar.
Alexandra Klemme, Tim Rixen, Denise Müller-Dum, Moritz Müller, Justus Notholt, and Thorsten Warneke
Biogeosciences, 19, 2855–2880, https://doi.org/10.5194/bg-19-2855-2022, https://doi.org/10.5194/bg-19-2855-2022, 2022
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Tropical peat-draining rivers contain high amounts of carbon. Surprisingly, measured carbon dioxide (CO2) emissions from those rivers are comparatively moderate. We compiled data from 10 Southeast Asian rivers and found that CO2 production within these rivers is hampered by low water pH, providing a natural threshold for CO2 emissions. Furthermore, we find that enhanced carbonate input, e.g. caused by human activities, suspends this natural threshold and causes increased CO2 emissions.
Stefan Noël, Maximilian Reuter, Michael Buchwitz, Jakob Borchardt, Michael Hilker, Oliver Schneising, Heinrich Bovensmann, John P. Burrows, Antonio Di Noia, Robert J. Parker, Hiroshi Suto, Yukio Yoshida, Matthias Buschmann, Nicholas M. Deutscher, Dietrich G. Feist, David W. T. Griffith, Frank Hase, Rigel Kivi, Cheng Liu, Isamu Morino, Justus Notholt, Young-Suk Oh, Hirofumi Ohyama, Christof Petri, David F. Pollard, Markus Rettinger, Coleen Roehl, Constantina Rousogenous, Mahesh Kumar Sha, Kei Shiomi, Kimberly Strong, Ralf Sussmann, Yao Té, Voltaire A. Velazco, Mihalis Vrekoussis, and Thorsten Warneke
Atmos. Meas. Tech., 15, 3401–3437, https://doi.org/10.5194/amt-15-3401-2022, https://doi.org/10.5194/amt-15-3401-2022, 2022
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We present a new version (v3) of the GOSAT and GOSAT-2 FOCAL products.
In addition to an increased number of XCO2 data, v3 also includes products for XCH4 (full-physics and proxy), XH2O and the relative ratio of HDO to H2O (δD). For GOSAT-2, we also present first XCO and XN2O results. All FOCAL data products show reasonable spatial distribution and temporal variations and agree well with TCCON. Global XN2O maps show a gradient from the tropics to higher latitudes on the order of 15 ppb.
Carlos Alberti, Frank Hase, Matthias Frey, Darko Dubravica, Thomas Blumenstock, Angelika Dehn, Paolo Castracane, Gregor Surawicz, Roland Harig, Bianca C. Baier, Caroline Bès, Jianrong Bi, Hartmut Boesch, André Butz, Zhaonan Cai, Jia Chen, Sean M. Crowell, Nicholas M. Deutscher, Dragos Ene, Jonathan E. Franklin, Omaira García, David Griffith, Bruno Grouiez, Michel Grutter, Abdelhamid Hamdouni, Sander Houweling, Neil Humpage, Nicole Jacobs, Sujong Jeong, Lilian Joly, Nicholas B. Jones, Denis Jouglet, Rigel Kivi, Ralph Kleinschek, Morgan Lopez, Diogo J. Medeiros, Isamu Morino, Nasrin Mostafavipak, Astrid Müller, Hirofumi Ohyama, Paul I. Palmer, Mahesh Pathakoti, David F. Pollard, Uwe Raffalski, Michel Ramonet, Robbie Ramsay, Mahesh Kumar Sha, Kei Shiomi, William Simpson, Wolfgang Stremme, Youwen Sun, Hiroshi Tanimoto, Yao Té, Gizaw Mengistu Tsidu, Voltaire A. Velazco, Felix Vogel, Masataka Watanabe, Chong Wei, Debra Wunch, Marcia Yamasoe, Lu Zhang, and Johannes Orphal
Atmos. Meas. Tech., 15, 2433–2463, https://doi.org/10.5194/amt-15-2433-2022, https://doi.org/10.5194/amt-15-2433-2022, 2022
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Space-borne greenhouse gas missions require ground-based validation networks capable of providing fiducial reference measurements. Here, considerable refinements of the calibration procedures for the COllaborative Carbon Column Observing Network (COCCON) are presented. Laboratory and solar side-by-side procedures for the characterization of the spectrometers have been refined and extended. Revised calibration factors for XCO2, XCO and XCH4 are provided, incorporating 47 new spectrometers.
Edward Malina, Ben Veihelmann, Matthias Buschmann, Nicholas M. Deutscher, Dietrich G. Feist, and Isamu Morino
Atmos. Meas. Tech., 15, 2377–2406, https://doi.org/10.5194/amt-15-2377-2022, https://doi.org/10.5194/amt-15-2377-2022, 2022
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Methane retrievals from remote sensing instruments are fundamentally based on spectroscopic parameters, which indicate spectral-line positions, and their characteristics. These parameters are stored in several databases that vary in their make-up. Here we assess how concentrations of methane isotopologues measured from the same Total Carbon Column Observing Network (TCCON) instruments vary across a range of spectral windows using different spectroscopic databases and comment on the implications.
Carlos Alberti, Qiansi Tu, Frank Hase, Maria V. Makarova, Konstantin Gribanov, Stefani C. Foka, Vyacheslav Zakharov, Thomas Blumenstock, Michael Buchwitz, Christopher Diekmann, Benjamin Ertl, Matthias M. Frey, Hamud Kh. Imhasin, Dmitry V. Ionov, Farahnaz Khosrawi, Sergey I. Osipov, Maximilian Reuter, Matthias Schneider, and Thorsten Warneke
Atmos. Meas. Tech., 15, 2199–2229, https://doi.org/10.5194/amt-15-2199-2022, https://doi.org/10.5194/amt-15-2199-2022, 2022
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Satellite and ground-based observations at high latitudes are much sparser than at low or mid latitudes, which makes direct coincident comparisons between remote-sensing observations more difficult. Therefore, a method of scaling continuous CAMS model data to the ground-based observations is developed and used for creating virtual COCCON observations. These adjusted CAMS data are then used for satellite inter-comparison, showing good agreement in both Peterhof and Yekaterinburg cities.
Hao Yin, Youwen Sun, Justus Notholt, Mathias Palm, and Cheng Liu
Atmos. Chem. Phys., 22, 4167–4185, https://doi.org/10.5194/acp-22-4167-2022, https://doi.org/10.5194/acp-22-4167-2022, 2022
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In this study, we quantity the long-term variabilities and the underlying drivers of NO2 from 2005 to 2020 over the Yangtze River Delta (YRD), one of the most densely populated and highly industrialized city clusters in China. We reveal the significant effect of the Action Plan on the Prevention and Control of Air Pollution since 2013 adopted by the Chinese government to reduce NOx pollution. Our study can improve the understanding of pollution control measures on a regional scale.
Thomas E. Taylor, Christopher W. O'Dell, David Crisp, Akhiko Kuze, Hannakaisa Lindqvist, Paul O. Wennberg, Abhishek Chatterjee, Michael Gunson, Annmarie Eldering, Brendan Fisher, Matthäus Kiel, Robert R. Nelson, Aronne Merrelli, Greg Osterman, Frédéric Chevallier, Paul I. Palmer, Liang Feng, Nicholas M. Deutscher, Manvendra K. Dubey, Dietrich G. Feist, Omaira E. García, David W. T. Griffith, Frank Hase, Laura T. Iraci, Rigel Kivi, Cheng Liu, Martine De Mazière, Isamu Morino, Justus Notholt, Young-Suk Oh, Hirofumi Ohyama, David F. Pollard, Markus Rettinger, Matthias Schneider, Coleen M. Roehl, Mahesh Kumar Sha, Kei Shiomi, Kimberly Strong, Ralf Sussmann, Yao Té, Voltaire A. Velazco, Mihalis Vrekoussis, Thorsten Warneke, and Debra Wunch
Earth Syst. Sci. Data, 14, 325–360, https://doi.org/10.5194/essd-14-325-2022, https://doi.org/10.5194/essd-14-325-2022, 2022
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We provide an analysis of an 11-year record of atmospheric carbon dioxide (CO2) concentrations derived using an optimal estimation retrieval algorithm on measurements made by the GOSAT satellite. The new product (version 9) shows improvement over the previous version (v7.3) as evaluated against independent estimates of CO2 from ground-based sensors and atmospheric inversion systems. We also compare the new GOSAT CO2 values to collocated estimates from NASA's Orbiting Carbon Observatory-2.
Youwen Sun, Hao Yin, Xiao Lu, Justus Notholt, Mathias Palm, Cheng Liu, Yuan Tian, and Bo Zheng
Atmos. Chem. Phys., 21, 18589–18608, https://doi.org/10.5194/acp-21-18589-2021, https://doi.org/10.5194/acp-21-18589-2021, 2021
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This study uses high-resolution nested-grid GEOS-Chem simulation, the eXtreme Gradient Boosting (XGBoost) machine learning method, and the exposure–response relationship to determine the drivers and evaluate the health risks of the unexpected surface O3 enhancements over the Sichuan Basin in 2020. These unexpected O3 enhancements were induced by meteorological anomalies and caused dramatically high health risks.
Joseph Mendonca, Ray Nassar, Christopher W. O'Dell, Rigel Kivi, Isamu Morino, Justus Notholt, Christof Petri, Kimberly Strong, and Debra Wunch
Atmos. Meas. Tech., 14, 7511–7524, https://doi.org/10.5194/amt-14-7511-2021, https://doi.org/10.5194/amt-14-7511-2021, 2021
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Machine learning has become an important tool for pattern recognition in many applications. In this study, we used a neural network to improve the data quality of OCO-2 measurements made at northern high latitudes. The neural network was trained and used as a binary classifier to filter out bad OCO-2 measurements in order to increase the accuracy and precision of OCO-2 XCO2 measurements in the Boreal and Arctic regions.
Nicole Jacobs, William R. Simpson, Kelly A. Graham, Christopher Holmes, Frank Hase, Thomas Blumenstock, Qiansi Tu, Matthias Frey, Manvendra K. Dubey, Harrison A. Parker, Debra Wunch, Rigel Kivi, Pauli Heikkinen, Justus Notholt, Christof Petri, and Thorsten Warneke
Atmos. Chem. Phys., 21, 16661–16687, https://doi.org/10.5194/acp-21-16661-2021, https://doi.org/10.5194/acp-21-16661-2021, 2021
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Spatial patterns of carbon dioxide seasonal cycle amplitude and summer drawdown timing derived from the OCO-2 satellite over northern high latitudes agree well with corresponding estimates from two models. The Asian boreal forest is anomalous with the largest amplitude and earliest seasonal drawdown. Modeled land contact tracers suggest that accumulated CO2 exchanges during atmospheric transport play a major role in shaping carbon dioxide seasonality in northern high-latitude regions.
Zhao-Cheng Zeng, Vijay Natraj, Feng Xu, Sihe Chen, Fang-Ying Gong, Thomas J. Pongetti, Keeyoon Sung, Geoffrey Toon, Stanley P. Sander, and Yuk L. Yung
Atmos. Meas. Tech., 14, 6483–6507, https://doi.org/10.5194/amt-14-6483-2021, https://doi.org/10.5194/amt-14-6483-2021, 2021
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Large carbon source regions such as megacities are also typically associated with heavy aerosol loading, which introduces uncertainties in the retrieval of greenhouse gases from reflected and scattered sunlight measurements. In this study, we developed a full physics algorithm to retrieve greenhouse gases in the presence of aerosols and demonstrated its performance by retrieving CO2 and CH4 columns from remote sensing measurements in the Los Angeles megacity.
Cited articles
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Blumenstock, T., Hase, F., Keens, A., Czurlok, D., Colebatch, O., Garcia, O., Griffith, D. W. T., Grutter, M., Hannigan, J. W., Heikkinen, P., Jeseck, P., Jones, N., Kivi, R., Lutsch, E., Makarova, M., Imhasin, H. K., Mellqvist, J., Morino, I., Nagahama, T., Notholt, J., Ortega, I., Palm, M., Raffalski, U., Rettinger, M., Robinson, J., Schneider, M., Servais, C., Smale, D., Stremme, W., Strong, K., Sussmann, R., Té, Y., and Velazco, V. A.: Characterization and potential for reducing optical resonances in Fourier transform infrared spectrometers of the Network for the Detection of Atmospheric Composition Change (NDACC), Atmos. Meas. Tech., 14, 1239–1252, https://doi.org/10.5194/amt-14-1239-2021, 2021. a, b
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Buschmann, M., Petri, C., Palm, M., Warneke, T., and Notholt, J.: TCCON data from Ny-Ålesund, Svalbard (NO), Release GGG2020.R0 (Version R0), CaltechDATA [data set], https://doi.org/10.14291/tccon.ggg2020.nyalesund01.R0, 2022. a, b
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Laughner, J. L., Roche, S., Kiel, M., Toon, G. C., Wunch, D., Baier, B. C., Biraud, S., Chen, H., Kivi, R., Laemmel, T., McKain, K., Quéhé, P.-Y., Rousogenous, C., Stephens, B. B., Walker, K., and Wennberg, P. O.: A new algorithm to generate a priori trace gas profiles for the GGG2020 retrieval algorithm, Atmos. Meas. Tech., 16, 1121–1146, https://doi.org/10.5194/amt-16-1121-2023, 2023a. a
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Short summary
The goal is to establish a window and strategy for xCO2 retrieval from ground-based Fourier transform spectrometers for NDACC. In the study we describe the spectroscopy of the region, the locations and instruments used, and the methods of calculating the retrieved xCO2. We performed tests to assess the sensitivity to diverse factors and sources of errors while comparing the retrieval to a well-established xCO2 retrieval from TCCON.
The goal is to establish a window and strategy for xCO2 retrieval from ground-based Fourier...
