Articles | Volume 24, issue 4
https://doi.org/10.5194/acp-24-2169-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/acp-24-2169-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Measurement report
| 
21 Feb 2024
Measurement report |
| 21 Feb 2024
| 21 Feb 2024
Measurement report: The Palau Atmospheric Observatory and its ozonesonde record – continuous monitoring of tropospheric composition and dynamics in the tropical western Pacific
Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Potsdam, Germany
Invited contribution by Katrin Müller, recipient of the EGU Atmospheric Sciences Outstanding Student Poster and PICO Award 2019.
Jordis S. Tradowsky
Norwegian Meteorological Institute, Oslo, Norway
Bodeker Scientific, Alexandra, New Zealand
Peter von der Gathen
Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Potsdam, Germany
Christoph Ritter
Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Potsdam, Germany
Sharon Patris
Coral Reef Research Foundation, Koror, Palau
Justus Notholt
Institut für Umweltphysik, University of Bremen, Bremen, Germany
Markus Rex
Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Potsdam, Germany
Institut für Physik und Astronomie, Universität Potsdam, Potsdam, Germany
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Katrin Müller, Peter von der Gathen, and Markus Rex
Atmos. Chem. Phys., 24, 4693–4716, https://doi.org/10.5194/acp-24-4693-2024, https://doi.org/10.5194/acp-24-4693-2024, 2024
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The transport history of tropospheric air masses above the tropical western Pacific is studied by local ozone and relative humidity profile measurements from Palau. A prominent anti-correlation between both tracers separates air masses of different origin and genesis. Back trajectories confirm a local convective origin of the year-round humid ozone-poor background. Anomalously dry ozone-rich air is generated in tropical Asia by pollution and dehydrated during transport via radiative cooling.
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.
Denghui Ji, Mathias Palm, Matthias Buschmann, Kerstin Ebell, Marion Maturilli, Xiaoyu Sun, and Justus Notholt
EGUsphere, https://doi.org/10.5194/egusphere-2024-2241, https://doi.org/10.5194/egusphere-2024-2241, 2024
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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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.
Falco Monsees, Alexei Rozanov, John P. Burrows, Mark Weber, Annette Rinke, Ralf Jaiser, and Peter von der Gathen
Atmos. Chem. Phys., 24, 9085–9099, https://doi.org/10.5194/acp-24-9085-2024, https://doi.org/10.5194/acp-24-9085-2024, 2024
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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.
Sandra Graßl, Christoph Ritter, Ines Tritscher, and Bärbel Vogel
Atmos. Chem. Phys., 24, 7535–7557, https://doi.org/10.5194/acp-24-7535-2024, https://doi.org/10.5194/acp-24-7535-2024, 2024
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Arctic lidar data for 1 year are compared with global modeling of aerosol tracers in the stratosphere. A trend in the aerosol backscatter can be found. These observations are further compared with a model study to investigate the aerosol origin of the observed arctic aerosol. We found a correlation with increased backscatter signal during summer and early autumn and pathways from the Southeast Asian monsoon region and remains of the Asian tropopause aerosol layer in the Arctic.
Jamal Makkor, Mathias Palm, Matthias Buschmann, Emmanuel Mahieu, Martyn P. Chipperfield, and Justus Notholt
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-93, https://doi.org/10.5194/amt-2024-93, 2024
Preprint under review for AMT
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During the years 1950 and 1951, Marcel Migeotte took regular solar measurements in form of paper rolls at the Jungfraujoch site. These historical spectra proved 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.
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.
Katrin Müller, Peter von der Gathen, and Markus Rex
Atmos. Chem. Phys., 24, 4693–4716, https://doi.org/10.5194/acp-24-4693-2024, https://doi.org/10.5194/acp-24-4693-2024, 2024
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The transport history of tropospheric air masses above the tropical western Pacific is studied by local ozone and relative humidity profile measurements from Palau. A prominent anti-correlation between both tracers separates air masses of different origin and genesis. Back trajectories confirm a local convective origin of the year-round humid ozone-poor background. Anomalously dry ozone-rich air is generated in tropical Asia by pollution and dehydrated during transport via radiative cooling.
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.
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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Basudev Swain, Marco Vountas, Adrien Deroubaix, Luca Lelli, Yanick Ziegler, Soheila Jafariserajehlou, Sachin S. Gunthe, Andreas Herber, Christoph Ritter, Hartmut Bösch, and John P. Burrows
Atmos. Meas. Tech., 17, 359–375, https://doi.org/10.5194/amt-17-359-2024, https://doi.org/10.5194/amt-17-359-2024, 2024
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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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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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Ghislain Motos, Gabriel Freitas, Paraskevi Georgakaki, Jörg Wieder, Guangyu Li, Wenche Aas, Chris Lunder, Radovan Krejci, Julie Thérèse Pasquier, Jan Henneberger, Robert Oscar David, Christoph Ritter, Claudia Mohr, Paul Zieger, and Athanasios Nenes
Atmos. Chem. Phys., 23, 13941–13956, https://doi.org/10.5194/acp-23-13941-2023, https://doi.org/10.5194/acp-23-13941-2023, 2023
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Low-altitude clouds play a key role in regulating the climate of the Arctic, a region that suffers from climate change more than any other on the planet. We gathered meteorological and aerosol physical and chemical data over a year and utilized them for a parameterization that help us unravel the factors driving and limiting the efficiency of cloud droplet formation. We then linked this information to the sources of aerosol found during each season and to processes of cloud glaciation.
Tim Poguntke and Christoph Ritter
Atmos. Meas. Tech., 16, 4009–4014, https://doi.org/10.5194/amt-16-4009-2023, https://doi.org/10.5194/amt-16-4009-2023, 2023
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In this work we analyze the impact of electromagnetic interference on an aerosol lidar. We found that aging transient recorders may produce a noise with fixed frequency that can be removed a posteriori.
Rafaella Chiarella, Matthias Buschmann, Joshua Laughner, Isamu Morino, Justus Notholt, Christof Petri, Geoffrey Toon, Voltaire A. Velazco, and Thorsten Warneke
Atmos. Meas. Tech., 16, 3987–4007, https://doi.org/10.5194/amt-16-3987-2023, https://doi.org/10.5194/amt-16-3987-2023, 2023
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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.
Bianca Zilker, Andreas Richter, Anne-Marlene Blechschmidt, Peter von der Gathen, Ilias Bougoudis, Sora Seo, Tim Bösch, and John Philip Burrows
Atmos. Chem. Phys., 23, 9787–9814, https://doi.org/10.5194/acp-23-9787-2023, https://doi.org/10.5194/acp-23-9787-2023, 2023
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During Arctic spring, near-surface ozone is depleted by bromine released from salty sea ice and/or snow-covered areas under certain meteorological conditions. To study this ozone depletion and the prevailing meteorological conditions, two ozone data sets from Ny-Ålesund, Svalbard, have been evaluated. We found that during ozone depletion events lower pressure over the Barents Sea and higher pressure in the Icelandic Low area led to a transport of cold polar air from the north to Ny-Ålesund.
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.
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.
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.
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.
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.
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.
Klaus Dethloff, Wieslaw Maslowski, Stefan Hendricks, Younjoo J. Lee, Helge F. Goessling, Thomas Krumpen, Christian Haas, Dörthe Handorf, Robert Ricker, Vladimir Bessonov, John J. Cassano, Jaclyn Clement Kinney, Robert Osinski, Markus Rex, Annette Rinke, Julia Sokolova, and Anja Sommerfeld
The Cryosphere, 16, 981–1005, https://doi.org/10.5194/tc-16-981-2022, https://doi.org/10.5194/tc-16-981-2022, 2022
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Sea ice thickness anomalies during the MOSAiC (Multidisciplinary drifting Observatory for the Study of Arctic Climate) winter in January, February and March 2020 were simulated with the coupled Regional Arctic climate System Model (RASM) and compared with CryoSat-2/SMOS satellite data. Hindcast and ensemble simulations indicate that the sea ice anomalies are driven by nonlinear interactions between ice growth processes and wind-driven sea-ice transports, with dynamics playing a dominant role.
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.
Kevin Ohneiser, Albert Ansmann, Alexandra Chudnovsky, Ronny Engelmann, Christoph Ritter, Igor Veselovskii, Holger Baars, Henriette Gebauer, Hannes Griesche, Martin Radenz, Julian Hofer, Dietrich Althausen, Sandro Dahlke, and Marion Maturilli
Atmos. Chem. Phys., 21, 15783–15808, https://doi.org/10.5194/acp-21-15783-2021, https://doi.org/10.5194/acp-21-15783-2021, 2021
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The highlight of the lidar measurements during the 1-year MOSAiC (Multidisciplinary drifting Observatory for the Study of Arctic Climate) expedition of the German icebreaker Polarstern (October 2019–October 2020) was the detection of a persistent, 10 km deep Siberian wildfire smoke layer in the upper troposphere and lower stratosphere (UTLS) from about 7–8 km to 17–18 km height that could potentially have impacted the record-breaking ozone depletion over the Arctic in the spring of 2020.
Mahesh Kumar Sha, Bavo Langerock, Jean-François L. Blavier, Thomas Blumenstock, Tobias Borsdorff, Matthias Buschmann, Angelika Dehn, Martine De Mazière, Nicholas M. Deutscher, Dietrich G. Feist, Omaira E. García, David W. T. Griffith, Michel Grutter, James W. Hannigan, Frank Hase, Pauli Heikkinen, Christian Hermans, Laura T. Iraci, Pascal Jeseck, Nicholas Jones, Rigel Kivi, Nicolas Kumps, Jochen Landgraf, Alba Lorente, Emmanuel Mahieu, Maria V. Makarova, Johan Mellqvist, Jean-Marc Metzger, Isamu Morino, Tomoo Nagahama, Justus Notholt, Hirofumi Ohyama, Ivan Ortega, Mathias Palm, Christof Petri, David F. Pollard, Markus Rettinger, John Robinson, Sébastien Roche, Coleen M. Roehl, Amelie N. Röhling, Constantina Rousogenous, Matthias Schneider, Kei Shiomi, Dan Smale, Wolfgang Stremme, Kimberly Strong, Ralf Sussmann, Yao Té, Osamu Uchino, Voltaire A. Velazco, Corinne Vigouroux, Mihalis Vrekoussis, Pucai Wang, Thorsten Warneke, Tyler Wizenberg, Debra Wunch, Shoma Yamanouchi, Yang Yang, and Minqiang Zhou
Atmos. Meas. Tech., 14, 6249–6304, https://doi.org/10.5194/amt-14-6249-2021, https://doi.org/10.5194/amt-14-6249-2021, 2021
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This paper presents, for the first time, Sentinel-5 Precursor methane and carbon monoxide validation results covering a period from November 2017 to September 2020. For this study, we used global TCCON and NDACC-IRWG network data covering a wide range of atmospheric and surface conditions across different terrains. We also show the influence of a priori alignment, smoothing uncertainties and the sensitivity of the validation results towards the application of advanced co-location criteria.
Youwen Sun, Hao Yin, Cheng Liu, Emmanuel Mahieu, Justus Notholt, Yao Té, Xiao Lu, Mathias Palm, Wei Wang, Changgong Shan, Qihou Hu, Min Qin, Yuan Tian, and Bo Zheng
Atmos. Chem. Phys., 21, 11759–11779, https://doi.org/10.5194/acp-21-11759-2021, https://doi.org/10.5194/acp-21-11759-2021, 2021
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The variability, sources, and transport of ethane (C2H6) over eastern China from 2015 to 2020 were studied using ground-based Fourier transform infrared (FTIR) spectroscopy and GEOS-Chem simulations. C2H6 variability is driven by both meteorological and emission factors. The reduction in C2H6 in recent years over eastern China points to air quality improvement in China.
Ilya Stanevich, Dylan B. A. Jones, Kimberly Strong, Martin Keller, Daven K. Henze, Robert J. Parker, Hartmut Boesch, Debra Wunch, Justus Notholt, Christof Petri, Thorsten Warneke, Ralf Sussmann, Matthias Schneider, Frank Hase, Rigel Kivi, Nicholas M. Deutscher, Voltaire A. Velazco, Kaley A. Walker, and Feng Deng
Atmos. Chem. Phys., 21, 9545–9572, https://doi.org/10.5194/acp-21-9545-2021, https://doi.org/10.5194/acp-21-9545-2021, 2021
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We explore the utility of a weak-constraint (WC) four-dimensional variational (4D-Var) data assimilation scheme for mitigating systematic errors in methane simulation in the GEOS-Chem model. We use data from the Greenhouse Gases Observing Satellite (GOSAT) and show that, compared to the traditional 4D-Var approach, the WC scheme improves the agreement between the model and independent observations. We find that the WC corrections to the model provide insight into the source of the errors.
Matthieu Dogniaux, Cyril Crevoisier, Raymond Armante, Virginie Capelle, Thibault Delahaye, Vincent Cassé, Martine De Mazière, Nicholas M. Deutscher, Dietrich G. Feist, Omaira E. Garcia, David W. T. Griffith, Frank Hase, Laura T. Iraci, Rigel Kivi, Isamu Morino, Justus Notholt, David F. Pollard, Coleen M. Roehl, Kei Shiomi, Kimberly Strong, Yao Té, Voltaire A. Velazco, and Thorsten Warneke
Atmos. Meas. Tech., 14, 4689–4706, https://doi.org/10.5194/amt-14-4689-2021, https://doi.org/10.5194/amt-14-4689-2021, 2021
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We present the Adaptable 4A Inversion (5AI), an implementation of the optimal estimation (OE) algorithm, relying on the Automatized Atmospheric Absorption Atlas (4A/OP) radiative transfer model, that enables the retrieval of greenhouse gas atmospheric weighted columns from infrared measurements. It is tested on a sample of Orbiting Carbon Observatory-2 observations, and its results satisfactorily compare to several reference products, thus showing the reliability of 5AI OE implementation.
Youwen Sun, Hao Yin, Yuan Cheng, Qianggong Zhang, Bo Zheng, Justus Notholt, Xiao Lu, Cheng Liu, Yuan Tian, and Jianguo Liu
Atmos. Chem. Phys., 21, 9201–9222, https://doi.org/10.5194/acp-21-9201-2021, https://doi.org/10.5194/acp-21-9201-2021, 2021
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We quantified the variability, source, and transport of urban CO over the Himalayas and Tibetan Plateau (HTP) by using measurement, model simulation, and the analysis of meteorological fields. Urban CO over the HTP is dominated by anthropogenic and biomass burning emissions from local, South Asia and East Asia, and oxidation sources. The decreasing trends in surface CO since 2015 in most cities over the HTP are attributed to the reduction in local and transported CO emissions in recent years.
Stefan Noël, Maximilian Reuter, Michael Buchwitz, Jakob Borchardt, Michael Hilker, Heinrich Bovensmann, John P. Burrows, Antonio Di Noia, Hiroshi Suto, Yukio Yoshida, Matthias Buschmann, Nicholas M. Deutscher, Dietrich G. Feist, David W. T. Griffith, Frank Hase, Rigel Kivi, Isamu Morino, Justus Notholt, Hirofumi Ohyama, Christof Petri, James R. Podolske, David F. Pollard, Mahesh Kumar Sha, Kei Shiomi, Ralf Sussmann, Yao Té, Voltaire A. Velazco, and Thorsten Warneke
Atmos. Meas. Tech., 14, 3837–3869, https://doi.org/10.5194/amt-14-3837-2021, https://doi.org/10.5194/amt-14-3837-2021, 2021
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We present the first GOSAT and GOSAT-2 XCO2 data derived with the FOCAL retrieval algorithm. Comparisons of the GOSAT-FOCAL product with other data reveal long-term agreement within about 1 ppm over 1 decade, differences in seasonal variations of about 0.5 ppm, and a mean regional bias to ground-based TCCON data of 0.56 ppm with a mean scatter of 1.89 ppm. GOSAT-2-FOCAL data are preliminary only, but first comparisons show that they compare well with the GOSAT-FOCAL results and TCCON.
Holger Winkler, Takayoshi Yamada, Yasuko Kasai, Uwe Berger, and Justus Notholt
Atmos. Chem. Phys., 21, 7579–7596, https://doi.org/10.5194/acp-21-7579-2021, https://doi.org/10.5194/acp-21-7579-2021, 2021
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Sprites are electrical discharges above thunderstorms. We performed model simulations of the chemical processes in sprites to compare them with measurements of chemical perturbations above sprite-producing thunderstorms.
Youwen Sun, Hao Yin, Cheng Liu, Lin Zhang, Yuan Cheng, Mathias Palm, Justus Notholt, Xiao Lu, Corinne Vigouroux, Bo Zheng, Wei Wang, Nicholas Jones, Changong Shan, Min Qin, Yuan Tian, Qihou Hu, Fanhao Meng, and Jianguo Liu
Atmos. Chem. Phys., 21, 6365–6387, https://doi.org/10.5194/acp-21-6365-2021, https://doi.org/10.5194/acp-21-6365-2021, 2021
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This study mapped the drivers of HCHO variability from 2015 to 2019 over eastern China. Hydroxyl (OH) radical production rates from HCHO photolysis were evaluated. The relative contributions of emitted and photochemical sources to the observed HCHO abundance were analyzed. Contributions of various emission sources and geographical regions to the observed HCHO summertime enhancements were determined.
Hella van Asperen, João Rafael Alves-Oliveira, Thorsten Warneke, Bruce Forsberg, Alessandro Carioca de Araújo, and Justus Notholt
Biogeosciences, 18, 2609–2625, https://doi.org/10.5194/bg-18-2609-2021, https://doi.org/10.5194/bg-18-2609-2021, 2021
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Termites are insects that are highly abundant in tropical ecosystems. It is known that termites emit CH4, an important greenhouse gas, but their absolute emission remains uncertain. In the Amazon rainforest, we measured CH4 emissions from termite nests and groups of termites. In addition, we tested a fast and non-destructive field method to estimate termite nest colony size. We found that termites play a significant role in an ecosystem's CH4 budget and probably emit more than currently assumed.
Thomas Blumenstock, Frank Hase, Axel Keens, Denis Czurlok, Orfeo Colebatch, Omaira Garcia, David W. T. Griffith, Michel Grutter, James W. Hannigan, Pauli Heikkinen, Pascal Jeseck, Nicholas Jones, Rigel Kivi, Erik Lutsch, Maria Makarova, Hamud K. Imhasin, Johan Mellqvist, Isamu Morino, Tomoo Nagahama, Justus Notholt, Ivan Ortega, Mathias Palm, Uwe Raffalski, Markus Rettinger, John Robinson, Matthias Schneider, Christian Servais, Dan Smale, Wolfgang Stremme, Kimberly Strong, Ralf Sussmann, Yao Té, and Voltaire A. Velazco
Atmos. Meas. Tech., 14, 1239–1252, https://doi.org/10.5194/amt-14-1239-2021, https://doi.org/10.5194/amt-14-1239-2021, 2021
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This study investigates the level of channeling (optical resonances) of each FTIR spectrometer within the Network for the Detection of Atmospheric Composition Change (NDACC). Since the air gap of the beam splitter is a significant source of channeling, we propose new beam splitters with an increased wedge of the air gap. This study shows the potential for reducing channeling in the FTIR spectrometers operated by the NDACC, thereby increasing the quality of recorded spectra across the network.
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.
Erik Lutsch, Kimberly Strong, Dylan B. A. Jones, Thomas Blumenstock, Stephanie Conway, Jenny A. Fisher, James W. Hannigan, Frank Hase, Yasuko Kasai, Emmanuel Mahieu, Maria Makarova, Isamu Morino, Tomoo Nagahama, Justus Notholt, Ivan Ortega, Mathias Palm, Anatoly V. Poberovskii, Ralf Sussmann, and Thorsten Warneke
Atmos. Chem. Phys., 20, 12813–12851, https://doi.org/10.5194/acp-20-12813-2020, https://doi.org/10.5194/acp-20-12813-2020, 2020
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This paper describes the use of a network of 10 Arctic and midlatitude ground-based FTIR measurement sites to detect enhancements of the wildfire tracers carbon monoxide, hydrogen cyanide, and ethane from 2003 to 2018. A tagged CO GEOS-Chem simulation is used for source attribution and to evaluate the relative contribution of CO sources to the FTIR measurements. The use of FTIR measurements allowed for the emission ratios of hydrogen cyanide and ethane to be quantified.
Dmitry M. Kabanov, Christoph Ritter, and Sergey M. Sakerin
Atmos. Meas. Tech., 13, 5303–5317, https://doi.org/10.5194/amt-13-5303-2020, https://doi.org/10.5194/amt-13-5303-2020, 2020
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Long-term photometer measurements of two sites on Spitsbergen, Barentsburg and Ny-Ålesund, in the European Arctic are presented and compared. We find slightly higher aerosol optical depths at Barentsburg and attribute this to a higher concentration of small particles.
Mahesh Kumar Sha, Martine De Mazière, Justus Notholt, Thomas Blumenstock, Huilin Chen, Angelika Dehn, David W. T. Griffith, Frank Hase, Pauli Heikkinen, Christian Hermans, Alex Hoffmann, Marko Huebner, Nicholas Jones, Rigel Kivi, Bavo Langerock, Christof Petri, Francis Scolas, Qiansi Tu, and Damien Weidmann
Atmos. Meas. Tech., 13, 4791–4839, https://doi.org/10.5194/amt-13-4791-2020, https://doi.org/10.5194/amt-13-4791-2020, 2020
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We present the results of the 2017 FRM4GHG campaign at the Sodankylä TCCON site aimed at characterising the assessment of several low-cost portable instruments for precise solar absorption measurements of column-averaged dry-air mole fractions of CO2, CH4, and CO. The test instruments provided stable and precise measurements of these gases with quantified small biases. This qualifies the instruments to complement TCCON and expand the global coverage of ground-based measurements of these gases.
Ilya Stanevich, Dylan B. A. Jones, Kimberly Strong, Robert J. Parker, Hartmut Boesch, Debra Wunch, Justus Notholt, Christof Petri, Thorsten Warneke, Ralf Sussmann, Matthias Schneider, Frank Hase, Rigel Kivi, Nicholas M. Deutscher, Voltaire A. Velazco, Kaley A. Walker, and Feng Deng
Geosci. Model Dev., 13, 3839–3862, https://doi.org/10.5194/gmd-13-3839-2020, https://doi.org/10.5194/gmd-13-3839-2020, 2020
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Systematic errors in atmospheric models pose a challenge for inverse modeling studies of methane (CH4) emissions. We evaluated the CH4 simulation in the GEOS-Chem model at the horizontal resolutions of 4° × 5° and 2° × 2.5°. Our analysis identified resolution-dependent biases in the model, which we attributed to discrepancies between the two model resolutions in vertical transport in the troposphere and in stratosphere–troposphere exchange.
Philipp Richter, Mathias Palm, Christine Weinzierl, Hannes Griesche, Penny M. Rowe, and Justus Notholt
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-266, https://doi.org/10.5194/amt-2020-266, 2020
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Optically thin clouds containing low amounts of water are difficult to observe, but due to their frequent presence they have a non-neglectible impact on Earth's radiative budget. Here we present a retrieval for mixed-phase clouds from thermal-infared spectra, measured using a FTIR spectrometer. Even in situations where the atmospheric windows in the far-infrared are not applicable, cloud optical depths, effective droplet radii and water paths of mixed-phase clouds can be retrieved.
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.
Thomas Krumpen, Florent Birrien, Frank Kauker, Thomas Rackow, Luisa von Albedyll, Michael Angelopoulos, H. Jakob Belter, Vladimir Bessonov, Ellen Damm, Klaus Dethloff, Jari Haapala, Christian Haas, Carolynn Harris, Stefan Hendricks, Jens Hoelemann, Mario Hoppmann, Lars Kaleschke, Michael Karcher, Nikolai Kolabutin, Ruibo Lei, Josefine Lenz, Anne Morgenstern, Marcel Nicolaus, Uwe Nixdorf, Tomash Petrovsky, Benjamin Rabe, Lasse Rabenstein, Markus Rex, Robert Ricker, Jan Rohde, Egor Shimanchuk, Suman Singha, Vasily Smolyanitsky, Vladimir Sokolov, Tim Stanton, Anna Timofeeva, Michel Tsamados, and Daniel Watkins
The Cryosphere, 14, 2173–2187, https://doi.org/10.5194/tc-14-2173-2020, https://doi.org/10.5194/tc-14-2173-2020, 2020
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In October 2019 the research vessel Polarstern was moored to an ice floe in order to travel with it on the 1-year-long MOSAiC journey through the Arctic. Here we provide historical context of the floe's evolution and initial state for upcoming studies. We show that the ice encountered on site was exceptionally thin and was formed on the shallow Siberian shelf. The analyses presented provide the initial state for the analysis and interpretation of upcoming biogeochemical and ecological studies.
Youwen Sun, Cheng Liu, Lin Zhang, Mathias Palm, Justus Notholt, Hao Yin, Corinne Vigouroux, Erik Lutsch, Wei Wang, Changong Shan, Thomas Blumenstock, Tomoo Nagahama, Isamu Morino, Emmanuel Mahieu, Kimberly Strong, Bavo Langerock, Martine De Mazière, Qihou Hu, Huifang Zhang, Christof Petri, and Jianguo Liu
Atmos. Chem. Phys., 20, 5437–5456, https://doi.org/10.5194/acp-20-5437-2020, https://doi.org/10.5194/acp-20-5437-2020, 2020
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We present multiyear time series of ground-based Fourier-transform infrared spectroscopy measurements of HCN in densely populated eastern China. The seasonality and interannual variability of tropospheric HCN columns were investigated. The potential sources that drive the observed HCN seasonality and interannual variability were determined using a GEOS-Chem tagged CO simulation, global fire maps, and potential source contribution function values calculated using HYSPLIT back trajectories.
Tatiana Nomokonova, Kerstin Ebell, Ulrich Löhnert, Marion Maturilli, and Christoph Ritter
Atmos. Chem. Phys., 20, 5157–5173, https://doi.org/10.5194/acp-20-5157-2020, https://doi.org/10.5194/acp-20-5157-2020, 2020
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This paper presents an influence of water vapor anomalies on cloud properties and their radiative effect at Ny-Ålesund. The study is based on a 2.5-year active and passive cloud observation and a radiative transfer model. The results show that moist and dry conditions are related to strong changes in cloud occurrence, phase partitioning, water path, and, consequently, modulate the surface radiative budget.
Maximilian Reuter, Michael Buchwitz, Oliver Schneising, Stefan Noël, Heinrich Bovensmann, John P. Burrows, Hartmut Boesch, Antonio Di Noia, Jasdeep Anand, Robert J. Parker, Peter Somkuti, Lianghai Wu, Otto P. Hasekamp, Ilse Aben, Akihiko Kuze, Hiroshi Suto, Kei Shiomi, Yukio Yoshida, Isamu Morino, David Crisp, Christopher W. O'Dell, Justus Notholt, Christof Petri, Thorsten Warneke, Voltaire A. Velazco, Nicholas M. Deutscher, David W. T. Griffith, Rigel Kivi, David F. Pollard, Frank Hase, Ralf Sussmann, Yao V. Té, Kimberly Strong, Sébastien Roche, Mahesh K. Sha, Martine De Mazière, Dietrich G. Feist, Laura T. Iraci, Coleen M. Roehl, Christian Retscher, and Dinand Schepers
Atmos. Meas. Tech., 13, 789–819, https://doi.org/10.5194/amt-13-789-2020, https://doi.org/10.5194/amt-13-789-2020, 2020
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We present new satellite-derived data sets of atmospheric carbon dioxide (CO2) and methane (CH4). The data products are column-averaged dry-air mole fractions of CO2 and CH4, denoted XCO2 and XCH4. The products cover the years 2003–2018 and are merged Level 2 (satellite footprints) and merged Level 3 (gridded at monthly time and 5° x 5° spatial resolution) products obtained from combining several individual sensor products. We present the merging algorithms and product validation results.
Jonas Simon Wilzewski, Anke Roiger, Johan Strandgren, Jochen Landgraf, Dietrich G. Feist, Voltaire A. Velazco, Nicholas M. Deutscher, Isamu Morino, Hirofumi Ohyama, Yao Té, Rigel Kivi, Thorsten Warneke, Justus Notholt, Manvendra Dubey, Ralf Sussmann, Markus Rettinger, Frank Hase, Kei Shiomi, and André Butz
Atmos. Meas. Tech., 13, 731–745, https://doi.org/10.5194/amt-13-731-2020, https://doi.org/10.5194/amt-13-731-2020, 2020
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Through spectral degradation of GOSAT measurements in the 1.6 and 2.0 μm spectral bands, we mimic a single-band, passive satellite sensor for monitoring of CO2 emissions at fine spatial scales. We compare retrievals of XCO2 from these bands to TCCON and native GOSAT retrievals. At spectral resolutions near 1.3 nm, XCO2 retrievals from both bands show promising performance, but the 2.0 μm band is favorable due to better noise performance and the potential to retrieve some aerosol information.
Oliver Schneising, Michael Buchwitz, Maximilian Reuter, Heinrich Bovensmann, John P. Burrows, Tobias Borsdorff, Nicholas M. Deutscher, Dietrich G. Feist, David W. T. Griffith, Frank Hase, Christian Hermans, Laura T. Iraci, Rigel Kivi, Jochen Landgraf, Isamu Morino, Justus Notholt, Christof Petri, David F. Pollard, Sébastien Roche, Kei Shiomi, Kimberly Strong, Ralf Sussmann, Voltaire A. Velazco, Thorsten Warneke, and Debra Wunch
Atmos. Meas. Tech., 12, 6771–6802, https://doi.org/10.5194/amt-12-6771-2019, https://doi.org/10.5194/amt-12-6771-2019, 2019
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We introduce an algorithm that is used to simultaneously derive the abundances of the important atmospheric constituents carbon monoxide and methane from the TROPOMI instrument onboard the Sentinel-5 Precursor satellite, which enables the determination of both gases with an unprecedented level of detail on a global scale. The quality of the resulting data sets is assessed and the first results are presented.
Susan S. Kulawik, Sean Crowell, David Baker, Junjie Liu, Kathryn McKain, Colm Sweeney, Sebastien C. Biraud, Steve Wofsy, Christopher W. O'Dell, Paul O. Wennberg, Debra Wunch, Coleen M. Roehl, Nicholas M. Deutscher, Matthäus Kiel, David W. T. Griffith, Voltaire A. Velazco, Justus Notholt, Thorsten Warneke, Christof Petri, Martine De Mazière, Mahesh K. Sha, Ralf Sussmann, Markus Rettinger, Dave F. Pollard, Isamu Morino, Osamu Uchino, Frank Hase, Dietrich G. Feist, Sébastien Roche, Kimberly Strong, Rigel Kivi, Laura Iraci, Kei Shiomi, Manvendra K. Dubey, Eliezer Sepulveda, Omaira Elena Garcia Rodriguez, Yao Té, Pascal Jeseck, Pauli Heikkinen, Edward J. Dlugokencky, Michael R. Gunson, Annmarie Eldering, David Crisp, Brendan Fisher, and Gregory B. Osterman
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2019-257, https://doi.org/10.5194/amt-2019-257, 2019
Publication in AMT not foreseen
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This paper provides a benchmark of OCO-2 v8 and ACOS-GOSAT v7.3 XCO2 and lowermost tropospheric (LMT) errors. The paper focuses on the systematic errors and subtracts out validation, co-location, and random errors, looks at the correlation scale-length (spatially and temporally) of systematic errors, finding that the scale lengths are similar to bias correction scale-lengths. The assimilates of the bias correction term is used to place an error on fluxes estimates.
Jacob K. Hedelius, Tai-Long He, Dylan B. A. Jones, Bianca C. Baier, Rebecca R. Buchholz, Martine De Mazière, Nicholas M. Deutscher, Manvendra K. Dubey, Dietrich G. Feist, David W. T. Griffith, Frank Hase, Laura T. Iraci, Pascal Jeseck, Matthäus Kiel, Rigel Kivi, Cheng Liu, Isamu Morino, Justus Notholt, Young-Suk Oh, Hirofumi Ohyama, David F. Pollard, Markus Rettinger, Sébastien Roche, Coleen M. Roehl, Matthias Schneider, Kei Shiomi, Kimberly Strong, Ralf Sussmann, Colm Sweeney, Yao Té, Osamu Uchino, Voltaire A. Velazco, Wei Wang, Thorsten Warneke, Paul O. Wennberg, Helen M. Worden, and Debra Wunch
Atmos. Meas. Tech., 12, 5547–5572, https://doi.org/10.5194/amt-12-5547-2019, https://doi.org/10.5194/amt-12-5547-2019, 2019
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We seek ways to improve the accuracy of column measurements of carbon monoxide (CO) – an important tracer of pollution – made from the MOPITT satellite instrument. We devise a filtering scheme which reduces the scatter and also eliminates bias among the MOPITT detectors. Compared to ground-based observations, MOPITT measurements are about 6 %–8 % higher. When MOPITT data are implemented in a global assimilation model, they tend to reduce the model mismatch with aircraft measurements.
Ingo Wohltmann, Ralph Lehmann, Georg A. Gottwald, Karsten Peters, Alain Protat, Valentin Louf, Christopher Williams, Wuhu Feng, and Markus Rex
Geosci. Model Dev., 12, 4387–4407, https://doi.org/10.5194/gmd-12-4387-2019, https://doi.org/10.5194/gmd-12-4387-2019, 2019
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We present a trajectory-based model for simulating the transport of air parcels by convection. Our model extends the approach of existing models by explicitly simulating vertical updraft velocities inside the clouds and the time that an air parcel spends inside the convective event.
Niall J. Ryan, Mathias Palm, Christoph G. Hoffmann, Jens Goliasch, and Justus Notholt
Atmos. Meas. Tech., 12, 4077–4089, https://doi.org/10.5194/amt-12-4077-2019, https://doi.org/10.5194/amt-12-4077-2019, 2019
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We present a new ground-based instrument (CORAM) that measures atmospheric carbon monoxide (CO) concentrations within approximately 47–87 km in altitude with a 1 h time resolution. The measurements are made at Ny-Ålesund (79° N), Svalbard, and add much-needed coverage to the high Arctic. The first measured CO profiles from winter 2017/2018 are compared to co-located measurements from the Aura MLS satellite instrument and show agreement on daily and monthly timescales.
Temesgen Yirdaw Berhe, Gizaw Mengistu Tsidu, Thomas Blumenstock, Frank Hase, Thomas von Clarmann, Justus Notholt, and Emmanuel Mahieu
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2019-209, https://doi.org/10.5194/amt-2019-209, 2019
Revised manuscript not accepted
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This study aims to assess the latitudinal variation of MIPAS version
V5R_CH4_220 and V5R_CH4_224 uncertainty. Furthermore, we analyze the relationship between these uncertainties and the variability of water vapor. Mainly, the high uncertainty found in tropics for MIPAS CH4 220 is highly associated with variability of water vapour. However, this effect has been reduced in the new updated MIPAS CH4 224 datasets due to jointly fitted water profile with methane.
Tatiana Nomokonova, Kerstin Ebell, Ulrich Löhnert, Marion Maturilli, Christoph Ritter, and Ewan O'Connor
Atmos. Chem. Phys., 19, 4105–4126, https://doi.org/10.5194/acp-19-4105-2019, https://doi.org/10.5194/acp-19-4105-2019, 2019
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In this study, properties of clouds at the French–German Arctic research station in Ny-Ålesund are related to in-cloud thermodynamic conditions. The dataset used was collected within the Arctic Amplification project with a set of active and passive remote instruments. The results are compared with a model output. Significant divergence in observations and modelling of single-layer ice and mixed-phase clouds was found.
Debra Wunch, Dylan B. A. Jones, Geoffrey C. Toon, Nicholas M. Deutscher, Frank Hase, Justus Notholt, Ralf Sussmann, Thorsten Warneke, Jeroen Kuenen, Hugo Denier van der Gon, Jenny A. Fisher, and Joannes D. Maasakkers
Atmos. Chem. Phys., 19, 3963–3980, https://doi.org/10.5194/acp-19-3963-2019, https://doi.org/10.5194/acp-19-3963-2019, 2019
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We used five atmospheric observatories in Europe measuring total column dry-air mole fractions of methane and carbon monoxide to infer methane emissions in the area between the observatories. We find that the methane emissions are overestimated by the state-of-the-art inventories, and that this is likely due, at least in part, to the inventory disaggregation. We find that there is significant uncertainty in the carbon monoxide inventories that requires further investigation.
Minqiang Zhou, Bavo Langerock, Kelley C. Wells, Dylan B. Millet, Corinne Vigouroux, Mahesh Kumar Sha, Christian Hermans, Jean-Marc Metzger, Rigel Kivi, Pauli Heikkinen, Dan Smale, David F. Pollard, Nicholas Jones, Nicholas M. Deutscher, Thomas Blumenstock, Matthias Schneider, Mathias Palm, Justus Notholt, James W. Hannigan, and Martine De Mazière
Atmos. Meas. Tech., 12, 1393–1408, https://doi.org/10.5194/amt-12-1393-2019, https://doi.org/10.5194/amt-12-1393-2019, 2019
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N2O is an important atmospheric gas which is observed by two ground-based FTIR networks (TCCON and NDACC). The difference between NDACC and TCCON XN2O measurements is discussed. It is found that the bias between the two networks is within their combined uncertainties. However, TCCON measurements are affected by a priori profiles. In addition, the TCCON and NDACC N2O measurements are compared with the GEOS-Chem model simulations.
Debora Griffin, Kaley A. Walker, Ingo Wohltmann, Sandip S. Dhomse, Markus Rex, Martyn P. Chipperfield, Wuhu Feng, Gloria L. Manney, Jane Liu, and David Tarasick
Atmos. Chem. Phys., 19, 577–601, https://doi.org/10.5194/acp-19-577-2019, https://doi.org/10.5194/acp-19-577-2019, 2019
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Ozone in the stratosphere is important to protect the Earth from UV radiation. Using measurements taken by the Atmospheric Chemistry Experiment satellite between 2005 and 2013, we examine different methods to calculate the ozone loss in the high Arctic and establish the altitude at which most of the ozone is destroyed. Our results show that the different methods agree within the uncertainties. Recommendations are made on which methods are most appropriate to use.
Denise Müller-Dum, Thorsten Warneke, Tim Rixen, Moritz Müller, Antje Baum, Aliki Christodoulou, Joanne Oakes, Bradley D. Eyre, and Justus Notholt
Biogeosciences, 16, 17–32, https://doi.org/10.5194/bg-16-17-2019, https://doi.org/10.5194/bg-16-17-2019, 2019
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Southeast Asian peat-draining rivers are potentially strong sources of carbon to the atmosphere due to the large amounts of organic carbon stored in those ecosystems. We present the first assessment of CO2 emissions from the Rajang River, the largest peat-draining river in Malaysia. The peatlands’ influence on the CO2 emissions from the Rajang River was smaller than expected, probably due to their proximity to the coast. Therefore, the Rajang was only a moderate source of CO2 to the atmosphere.
Christopher W. O'Dell, Annmarie Eldering, Paul O. Wennberg, David Crisp, Michael R. Gunson, Brendan Fisher, Christian Frankenberg, Matthäus Kiel, Hannakaisa Lindqvist, Lukas Mandrake, Aronne Merrelli, Vijay Natraj, Robert R. Nelson, Gregory B. Osterman, Vivienne H. Payne, Thomas E. Taylor, Debra Wunch, Brian J. Drouin, Fabiano Oyafuso, Albert Chang, James McDuffie, Michael Smyth, David F. Baker, Sourish Basu, Frédéric Chevallier, Sean M. R. Crowell, Liang Feng, Paul I. Palmer, Mavendra Dubey, Omaira E. García, David W. T. Griffith, Frank Hase, Laura T. Iraci, Rigel Kivi, Isamu Morino, Justus Notholt, Hirofumi Ohyama, Christof Petri, Coleen M. Roehl, Mahesh K. Sha, Kimberly Strong, Ralf Sussmann, Yao Te, Osamu Uchino, and Voltaire A. Velazco
Atmos. Meas. Tech., 11, 6539–6576, https://doi.org/10.5194/amt-11-6539-2018, https://doi.org/10.5194/amt-11-6539-2018, 2018
Simone Brunamonti, Teresa Jorge, Peter Oelsner, Sreeharsha Hanumanthu, Bhupendra B. Singh, K. Ravi Kumar, Sunil Sonbawne, Susanne Meier, Deepak Singh, Frank G. Wienhold, Bei Ping Luo, Maxi Boettcher, Yann Poltera, Hannu Jauhiainen, Rijan Kayastha, Jagadishwor Karmacharya, Ruud Dirksen, Manish Naja, Markus Rex, Suvarna Fadnavis, and Thomas Peter
Atmos. Chem. Phys., 18, 15937–15957, https://doi.org/10.5194/acp-18-15937-2018, https://doi.org/10.5194/acp-18-15937-2018, 2018
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Based on balloon-borne measurements performed in India and Nepal in 2016–2017, we infer the vertical distributions of water vapor, ozone and aerosols in the atmosphere, from the surface to 30 km altitude. Our measurements show that the atmospheric dynamics of the Asian summer monsoon system over the polluted Indian subcontinent lead to increased concentrations of water vapor and aerosols in the high atmosphere (approximately 14–20 km altitude), which can have an important effect on climate.
Youwen Sun, Cheng Liu, Mathias Palm, Corinne Vigouroux, Justus Notholt, Qihou Hu, Nicholas Jones, Wei Wang, Wenjing Su, Wenqiang Zhang, Changong Shan, Yuan Tian, Xingwei Xu, Martine De Mazière, Minqiang Zhou, and Jianguo Liu
Atmos. Chem. Phys., 18, 14569–14583, https://doi.org/10.5194/acp-18-14569-2018, https://doi.org/10.5194/acp-18-14569-2018, 2018
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The seasonal evolution of O3 and its photochemical production regime in a polluted region of eastern China between 2014 and 2017 was investigated using FTS observations. We observed a broad summer O3 maximum in Hefei, China, and the ozone production is mainly NOx limited in spring and summer and is mainly VOC or mixed VOC–NOx limited in autumn and winter.
Corinne Vigouroux, Carlos Augusto Bauer Aquino, Maite Bauwens, Cornelis Becker, Thomas Blumenstock, Martine De Mazière, Omaira García, Michel Grutter, César Guarin, James Hannigan, Frank Hase, Nicholas Jones, Rigel Kivi, Dmitry Koshelev, Bavo Langerock, Erik Lutsch, Maria Makarova, Jean-Marc Metzger, Jean-François Müller, Justus Notholt, Ivan Ortega, Mathias Palm, Clare Paton-Walsh, Anatoly Poberovskii, Markus Rettinger, John Robinson, Dan Smale, Trissevgeni Stavrakou, Wolfgang Stremme, Kim Strong, Ralf Sussmann, Yao Té, and Geoffrey Toon
Atmos. Meas. Tech., 11, 5049–5073, https://doi.org/10.5194/amt-11-5049-2018, https://doi.org/10.5194/amt-11-5049-2018, 2018
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A few ground-based stations have provided time series of HCHO columns until now, which was not optimal for providing good diagnostics for satellite or model validation. In this work, HCHO time series have been determined in a harmonized way at 21 stations ensuring, in addition to a better spatial and level of abundances coverage, that internal biases within the network have been minimized. This data set shows consistent good agreement with model data and is ready for future satellite validation.
Justyna Lisok, Anna Rozwadowska, Jesper G. Pedersen, Krzysztof M. Markowicz, Christoph Ritter, Jacek W. Kaminski, Joanna Struzewska, Mauro Mazzola, Roberto Udisti, Silvia Becagli, and Izabela Gorecka
Atmos. Chem. Phys., 18, 8829–8848, https://doi.org/10.5194/acp-18-8829-2018, https://doi.org/10.5194/acp-18-8829-2018, 2018
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The aim of the presented study was to investigate the impact on the radiation budget and atmospheric dynamics of a biomass-burning plume, transported from Alaska to the High Arctic region of Ny-Ålesund, Svalbard, in early July 2015. We found that the smoke plume may significantly alter radiative properties of the atmosphere. Furthermore, the simulations of atmospheric dynamics indicated a vertical positive displacement and broadening of the plume with time.
Lianghai Wu, Otto Hasekamp, Haili Hu, Jochen Landgraf, Andre Butz, Joost aan de Brugh, Ilse Aben, Dave F. Pollard, David W. T. Griffith, Dietrich G. Feist, Dmitry Koshelev, Frank Hase, Geoffrey C. Toon, Hirofumi Ohyama, Isamu Morino, Justus Notholt, Kei Shiomi, Laura Iraci, Matthias Schneider, Martine de Mazière, Ralf Sussmann, Rigel Kivi, Thorsten Warneke, Tae-Young Goo, and Yao Té
Atmos. Meas. Tech., 11, 3111–3130, https://doi.org/10.5194/amt-11-3111-2018, https://doi.org/10.5194/amt-11-3111-2018, 2018
Youwen Sun, Mathias Palm, Cheng Liu, Frank Hase, David Griffith, Christine Weinzierl, Christof Petri, Wei Wang, and Justus Notholt
Atmos. Meas. Tech., 11, 2879–2896, https://doi.org/10.5194/amt-11-2879-2018, https://doi.org/10.5194/amt-11-2879-2018, 2018
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We simulated instrumental line shape (ILS) degradations with respect to typical types of misalignment, and compared their influence on each NDACC gas. The requirements to suppress the ILS-degradation-related biases within a specified accuracy for all NDACC gases were deduced.
Daniel Kreyling, Ingo Wohltmann, Ralph Lehmann, and Markus Rex
Geosci. Model Dev., 11, 753–769, https://doi.org/10.5194/gmd-11-753-2018, https://doi.org/10.5194/gmd-11-753-2018, 2018
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The Extrapolar SWIFT model is a fast yet accurate stratospheric ozone chemistry module for global climate models. The importance of feedbacks between the climate system and the ozone layer has been demonstrated in previous studies. Therefore it is desirable to include an interactive ozone layer in climate simulations. However, ensemble simulations in particular have strict computational constraints. The Extrapolar SWIFT model provides an interactive ozone layer with small computational costs.
Niall J. Ryan, Douglas E. Kinnison, Rolando R. Garcia, Christoph G. Hoffmann, Mathias Palm, Uwe Raffalski, and Justus Notholt
Atmos. Chem. Phys., 18, 1457–1474, https://doi.org/10.5194/acp-18-1457-2018, https://doi.org/10.5194/acp-18-1457-2018, 2018
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We used model output and instrument data to assess how well polar atmospheric descent rates can be derived using concentration measurements of long-lived gases in the atmosphere. The results indicate that the method incurs errors as large as the descent rates, and often leads to a misinterpretation of the direction of air motion. The rates derived using this method do not appear to represent the mean vertical wind in the middle atmosphere, and we suggest an alternate definition.
Zhiting Wang, Thorsten Warneke, Nicholas M. Deutscher, Justus Notholt, Ute Karstens, Marielle Saunois, Matthias Schneider, Ralf Sussmann, Harjinder Sembhi, David W. T. Griffith, Dave F. Pollard, Rigel Kivi, Christof Petri, Voltaire A. Velazco, Michel Ramonet, and Huilin Chen
Atmos. Chem. Phys., 17, 13283–13295, https://doi.org/10.5194/acp-17-13283-2017, https://doi.org/10.5194/acp-17-13283-2017, 2017
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In this paper we separate the biases of atmospheric methane models into stratospheric and tropospheric parts. It is observed in other studies that simulated total columns of atmospheric methane present a latitudinal bias compared to measurements. The latitudinal gradients are considered to be from the stratosphere. However, our results show that the latitudinal biases could come from the troposphere in two of three models evaluated in this study.
Nils Hase, Scot M. Miller, Peter Maaß, Justus Notholt, Mathias Palm, and Thorsten Warneke
Geosci. Model Dev., 10, 3695–3713, https://doi.org/10.5194/gmd-10-3695-2017, https://doi.org/10.5194/gmd-10-3695-2017, 2017
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Inverse modeling uses atmospheric measurements to estimate emissions of greenhouse gases, which are key to understand the climate system. However, the measurement information alone is typically insufficient to provide reasonable emission estimates. Additional information is required. This article applies modern mathematical inversion techniques to formulate such additional knowledge. It is a prime example of how such tools can improve the quality of estimates compared to commonly used methods.
Kevin S. Olsen, Kimberly Strong, Kaley A. Walker, Chris D. Boone, Piera Raspollini, Johannes Plieninger, Whitney Bader, Stephanie Conway, Michel Grutter, James W. Hannigan, Frank Hase, Nicholas Jones, Martine de Mazière, Justus Notholt, Matthias Schneider, Dan Smale, Ralf Sussmann, and Naoko Saitoh
Atmos. Meas. Tech., 10, 3697–3718, https://doi.org/10.5194/amt-10-3697-2017, https://doi.org/10.5194/amt-10-3697-2017, 2017
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The primary instrument on the Greenhouse gases Observing SATellite (GOSAT) is the Thermal And Near infrared Sensor for carbon Observations (TANSO) Fourier transform spectrometer (FTS). TANSO-FTS has a thermal infrared channel to retrieve vertical profiles of CO2 and CH4 volume mixing ratios in the troposphere. We compare the retrieved vertical profiles of CH4 from TANSO-FTS with those from two other spaceborne FTSs and with ground-based FTS observatories to assess their quality.
Ingo Wohltmann, Ralph Lehmann, and Markus Rex
Atmos. Chem. Phys., 17, 10535–10563, https://doi.org/10.5194/acp-17-10535-2017, https://doi.org/10.5194/acp-17-10535-2017, 2017
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We present a quantitative analysis of the chemical reactions involved in polar ozone depletion in the stratosphere, and of the relevant reaction pathways and cycles. We show time series of reaction rates averaged over the core of the polar vortex in winter and spring for all relevant reactions. An emphasis is put on the partitioning of the relevant chemical families (nitrogen, hydrogen, chlorine, bromine and odd oxygen) and activation and deactivation of chlorine.
Wei Wang, Yuan Tian, Cheng Liu, Youwen Sun, Wenqing Liu, Pinhua Xie, Jianguo Liu, Jin Xu, Isamu Morino, Voltaire A. Velazco, David W. T. Griffith, Justus Notholt, and Thorsten Warneke
Atmos. Meas. Tech., 10, 2627–2643, https://doi.org/10.5194/amt-10-2627-2017, https://doi.org/10.5194/amt-10-2627-2017, 2017
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A ground-based high-resolution Fourier transform spectrometer (FTS) station has been established in Hefei, China to remotely measure CO2, CO and other greenhouse gases. Our research aim is to provide information for constraining regional sources and sinks, and validate satellite data, such as GOSAT, OCO-2 and TANSAT. We investigate the potential of FTS to determine the temporal variability of atmospheric CO2 and CO, and assess the ability of our observations to validate satellite data.
Guanyu Huang, Xiong Liu, Kelly Chance, Kai Yang, Pawan K. Bhartia, Zhaonan Cai, Marc Allaart, Gérard Ancellet, Bertrand Calpini, Gerrie J. R. Coetzee, Emilio Cuevas-Agulló, Manuel Cupeiro, Hugo De Backer, Manvendra K. Dubey, Henry E. Fuelberg, Masatomo Fujiwara, Sophie Godin-Beekmann, Tristan J. Hall, Bryan Johnson, Everette Joseph, Rigel Kivi, Bogumil Kois, Ninong Komala, Gert König-Langlo, Giovanni Laneve, Thierry Leblanc, Marion Marchand, Kenneth R. Minschwaner, Gary Morris, Michael J. Newchurch, Shin-Ya Ogino, Nozomu Ohkawara, Ankie J. M. Piters, Françoise Posny, Richard Querel, Rinus Scheele, Frank J. Schmidlin, Russell C. Schnell, Otto Schrems, Henry Selkirk, Masato Shiotani, Pavla Skrivánková, René Stübi, Ghassan Taha, David W. Tarasick, Anne M. Thompson, Valérie Thouret, Matthew B. Tully, Roeland Van Malderen, Holger Vömel, Peter von der Gathen, Jacquelyn C. Witte, and Margarita Yela
Atmos. Meas. Tech., 10, 2455–2475, https://doi.org/10.5194/amt-10-2455-2017, https://doi.org/10.5194/amt-10-2455-2017, 2017
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It is essential to understand the data quality of +10-year OMI ozone product and impacts of the “row anomaly” (RA). We validate the OMI Ozone Profile (PROFOZ) product from Oct 2004 to Dec 2014 against ozonesonde observations globally. Generally, OMI has good agreement with ozonesondes. The spatiotemporal variation of retrieval performance suggests the need to improve OMI’s radiometric calibration especially during the post-RA period to maintain the long-term stability.
Ingo Wohltmann, Ralph Lehmann, and Markus Rex
Geosci. Model Dev., 10, 2671–2689, https://doi.org/10.5194/gmd-10-2671-2017, https://doi.org/10.5194/gmd-10-2671-2017, 2017
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The Polar SWIFT model is a fast scheme for calculating the chemistry of stratospheric ozone depletion in polar winter. It is intended for use in global climate models (GCMs) and Earth system models (ESMs) to enable the simulation of mutual interactions between the ozone layer and climate.
Matthias Buschmann, Nicholas M. Deutscher, Mathias Palm, Thorsten Warneke, Christine Weinzierl, and Justus Notholt
Atmos. Meas. Tech., 10, 2397–2411, https://doi.org/10.5194/amt-10-2397-2017, https://doi.org/10.5194/amt-10-2397-2017, 2017
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The column averaged dry-air mole fractions of CO2 and CH4 (xCO2 and xCH4) of the Total Carbon Column Observing Network (TCCON) are retrieved from solar absorption Fourier transform infrared (FTIR) spectrometry. At the Ny-Ålesund site in the high arctic, however, during the polar night no solar measurements are possible. Here, we present a new method to measure xCO2 and xCH4 using the moon as a light source in the near-infrared and present the complete seasonal cycles of xCO2 and xCH4.
Debra Wunch, Paul O. Wennberg, Gregory Osterman, Brendan Fisher, Bret Naylor, Coleen M. Roehl, Christopher O'Dell, Lukas Mandrake, Camille Viatte, Matthäus Kiel, David W. T. Griffith, Nicholas M. Deutscher, Voltaire A. Velazco, Justus Notholt, Thorsten Warneke, Christof Petri, Martine De Maziere, Mahesh K. Sha, Ralf Sussmann, Markus Rettinger, David Pollard, John Robinson, Isamu Morino, Osamu Uchino, Frank Hase, Thomas Blumenstock, Dietrich G. Feist, Sabrina G. Arnold, Kimberly Strong, Joseph Mendonca, Rigel Kivi, Pauli Heikkinen, Laura Iraci, James Podolske, Patrick W. Hillyard, Shuji Kawakami, Manvendra K. Dubey, Harrison A. Parker, Eliezer Sepulveda, Omaira E. García, Yao Te, Pascal Jeseck, Michael R. Gunson, David Crisp, and Annmarie Eldering
Atmos. Meas. Tech., 10, 2209–2238, https://doi.org/10.5194/amt-10-2209-2017, https://doi.org/10.5194/amt-10-2209-2017, 2017
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This paper describes the comparisons between NASA's Orbiting Carbon Observatory (OCO-2) column-averaged dry-air mole fractions of CO2 with its primary ground-based validation network, the Total Carbon Column Observing Network (TCCON). The paper shows that while the standard bias correction reduces much of the spurious variability in the satellite measurements, residual biases remain.
Zhiting Wang, Thorsten Warneke, Bart Dils, Justus Notholt, and Marielle Saunois
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2017-435, https://doi.org/10.5194/acp-2017-435, 2017
Revised manuscript not accepted
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It is important to know to what extent the chemistry transport model represents tracer transport in the atmosphere correctly. In this study we evaluate performances of three models in the stratosphere in describing mixing processes there. The results reveal that deficiencies exist in representing mixing processes in mid-latitudes of southern stratosphere. Another related problem of the models is in representing tracer gradients across transport barrier.
Youwen Sun, Mathias Palm, Christine Weinzierl, Christof Petri, Justus Notholt, Yuting Wang, and Cheng Liu
Atmos. Meas. Tech., 10, 989–997, https://doi.org/10.5194/amt-10-989-2017, https://doi.org/10.5194/amt-10-989-2017, 2017
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We first design experiments to investigate the sensitivity of ILS (instrumental line shape) monitoring for a high-resolution FTIR spectrometer within the TCCON and NDACC networks with respect to different optical attenuators. The ILS characteristics derived from lamp and sun spectra are in good agreement. A potential strategy to adapt incident intensity of a detector was deduced.
Niall J. Ryan, Mathias Palm, Uwe Raffalski, Richard Larsson, Gloria Manney, Luis Millán, and Justus Notholt
Earth Syst. Sci. Data, 9, 77–89, https://doi.org/10.5194/essd-9-77-2017, https://doi.org/10.5194/essd-9-77-2017, 2017
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We present a self-consistent data set of carbon monoxide (CO) in the Arctic middle atmosphere above Kiruna, Sweden, between 2008 and 2015. The data are retrieved from measurements made by the ground-based radiometer, KIMRA, and are compared to coincident CO data measured by the satellite instrument MLS. KIMRA shows agreement with MLS over the altitude range in which KIMRA is sensitive (48–84 km) and the data show the signatures of dynamic processes such as sudden stratospheric warmings.
Dmitry A. Belikov, Shamil Maksyutov, Alexander Ganshin, Ruslan Zhuravlev, Nicholas M. Deutscher, Debra Wunch, Dietrich G. Feist, Isamu Morino, Robert J. Parker, Kimberly Strong, Yukio Yoshida, Andrey Bril, Sergey Oshchepkov, Hartmut Boesch, Manvendra K. Dubey, David Griffith, Will Hewson, Rigel Kivi, Joseph Mendonca, Justus Notholt, Matthias Schneider, Ralf Sussmann, Voltaire A. Velazco, and Shuji Aoki
Atmos. Chem. Phys., 17, 143–157, https://doi.org/10.5194/acp-17-143-2017, https://doi.org/10.5194/acp-17-143-2017, 2017
Katherine M. Saad, Debra Wunch, Nicholas M. Deutscher, David W. T. Griffith, Frank Hase, Martine De Mazière, Justus Notholt, David F. Pollard, Coleen M. Roehl, Matthias Schneider, Ralf Sussmann, Thorsten Warneke, and Paul O. Wennberg
Atmos. Chem. Phys., 16, 14003–14024, https://doi.org/10.5194/acp-16-14003-2016, https://doi.org/10.5194/acp-16-14003-2016, 2016
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Current approaches to constrain the global methane budget assimilate total column measurements into models, but model biases can impact results. We use tropospheric methane columns to evaluate model transport errors and identify a seasonal time lag in the Northern Hemisphere troposphere masked by stratospheric compensating effects. We find systematic biases in the stratosphere will alias into model-derived emissions estimates, especially those in the high Northern latitudes that vary seasonally.
Enrico Dammers, Mathias Palm, Martin Van Damme, Corinne Vigouroux, Dan Smale, Stephanie Conway, Geoffrey C. Toon, Nicholas Jones, Eric Nussbaumer, Thorsten Warneke, Christof Petri, Lieven Clarisse, Cathy Clerbaux, Christian Hermans, Erik Lutsch, Kim Strong, James W. Hannigan, Hideaki Nakajima, Isamu Morino, Beatriz Herrera, Wolfgang Stremme, Michel Grutter, Martijn Schaap, Roy J. Wichink Kruit, Justus Notholt, Pierre-F. Coheur, and Jan Willem Erisman
Atmos. Chem. Phys., 16, 10351–10368, https://doi.org/10.5194/acp-16-10351-2016, https://doi.org/10.5194/acp-16-10351-2016, 2016
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Atmospheric ammonia (NH3) measured by the IASI satellite instrument is compared to observations from ground-based FTIR instruments. The seasonal cycles of NH3 in both datasets are consistent for most sites. Correlations are found to be high at sites with considerable NH3 levels, whereas correlations are lower at sites with low NH3 levels close to the detection limit of the IASI instrument. The study's results further indicate that the IASI-NH3 product performs better than earlier estimates.
Makoto Inoue, Isamu Morino, Osamu Uchino, Takahiro Nakatsuru, Yukio Yoshida, Tatsuya Yokota, Debra Wunch, Paul O. Wennberg, Coleen M. Roehl, David W. T. Griffith, Voltaire A. Velazco, Nicholas M. Deutscher, Thorsten Warneke, Justus Notholt, John Robinson, Vanessa Sherlock, Frank Hase, Thomas Blumenstock, Markus Rettinger, Ralf Sussmann, Esko Kyrö, Rigel Kivi, Kei Shiomi, Shuji Kawakami, Martine De Mazière, Sabrina G. Arnold, Dietrich G. Feist, Erica A. Barrow, James Barney, Manvendra Dubey, Matthias Schneider, Laura T. Iraci, James R. Podolske, Patrick W. Hillyard, Toshinobu Machida, Yousuke Sawa, Kazuhiro Tsuboi, Hidekazu Matsueda, Colm Sweeney, Pieter P. Tans, Arlyn E. Andrews, Sebastien C. Biraud, Yukio Fukuyama, Jasna V. Pittman, Eric A. Kort, and Tomoaki Tanaka
Atmos. Meas. Tech., 9, 3491–3512, https://doi.org/10.5194/amt-9-3491-2016, https://doi.org/10.5194/amt-9-3491-2016, 2016
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In this study, we correct the biases of GOSAT XCO2 and XCH4 using TCCON data. To evaluate the effectiveness of our correction method, uncorrected/corrected GOSAT data are compared to independent XCO2 and XCH4 data derived from aircraft measurements. Consequently, we suggest that this method is effective for reducing the biases of the GOSAT data. We consider that our work provides GOSAT data users with valuable information and contributes to the further development of studies on greenhouse gases.
Daan Hubert, Jean-Christopher Lambert, Tijl Verhoelst, José Granville, Arno Keppens, Jean-Luc Baray, Adam E. Bourassa, Ugo Cortesi, Doug A. Degenstein, Lucien Froidevaux, Sophie Godin-Beekmann, Karl W. Hoppel, Bryan J. Johnson, Erkki Kyrölä, Thierry Leblanc, Günter Lichtenberg, Marion Marchand, C. Thomas McElroy, Donal Murtagh, Hideaki Nakane, Thierry Portafaix, Richard Querel, James M. Russell III, Jacobo Salvador, Herman G. J. Smit, Kerstin Stebel, Wolfgang Steinbrecht, Kevin B. Strawbridge, René Stübi, Daan P. J. Swart, Ghassan Taha, David W. Tarasick, Anne M. Thompson, Joachim Urban, Joanna A. E. van Gijsel, Roeland Van Malderen, Peter von der Gathen, Kaley A. Walker, Elian Wolfram, and Joseph M. Zawodny
Atmos. Meas. Tech., 9, 2497–2534, https://doi.org/10.5194/amt-9-2497-2016, https://doi.org/10.5194/amt-9-2497-2016, 2016
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A more detailed understanding of satellite O3 profile data records is vital for further progress in O3 research. To this end, we made a comprehensive assessment of 14 limb/occultation profilers using ground-based reference data. The mutual consistency of satellite O3 in terms of bias, short-term variability and decadal stability is generally good over most of the stratosphere. However, we identified some exceptions that impact the quality of recently merged data sets and ozone trend assessments.
Marion Maturilli and Christoph Ritter
Earth Syst. Sci. Data, 8, 159–164, https://doi.org/10.5194/essd-8-159-2016, https://doi.org/10.5194/essd-8-159-2016, 2016
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The total solar eclipse over Ny-Ålesund (78.9° N, 11.9° E), Svalbard, on 20 March 2015 has been followed by various sensors. Here, we present the surface radiation measurements in the context of the meteorological observations, providing basic data for further studies on e.g. radiative transfer or micrometeorology.
Hideaki Nakajima, Ingo Wohltmann, Tobias Wegner, Masanori Takeda, Michael C. Pitts, Lamont R. Poole, Ralph Lehmann, Michelle L. Santee, and Markus Rex
Atmos. Chem. Phys., 16, 3311–3325, https://doi.org/10.5194/acp-16-3311-2016, https://doi.org/10.5194/acp-16-3311-2016, 2016
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This paper presents the first trial of analyzing amount of chlorine activation on different PSC compositions by using match analysis on trajectories initiated from PSC locations identified by CALIPSO/CALIOP measurements. The measured minor species such as HCl and ClO by MLS are compared with ATLAS chemistry-transport model (CTM) results. PSC growth to NAT, NAT/STS mixture, and ice were identified by different temperature decrease histories on trajectories.
R. Schofield, L. M. Avallone, L. E. Kalnajs, A. Hertzog, I. Wohltmann, and M. Rex
Atmos. Chem. Phys., 15, 2463–2472, https://doi.org/10.5194/acp-15-2463-2015, https://doi.org/10.5194/acp-15-2463-2015, 2015
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Ozone measurements onboard three Concordiasi balloons flown in the stratosphere in
the Antarctic spring of 2010 are presented. These measurements are the first long-duration in situ measurements of Antarctic springtime stratospheric ozone. By matching air parcels, ozone loss rates where derived. Downwind of the Antarctic Peninsula, very large ozone losses of up to 230 ppb per day or 16 ppbv per sunlit hour were observed. These high rates are consistent with almost complete chlorine activation.
M. Rex, S. Kremser, P. Huck, G. Bodeker, I. Wohltmann, M. L. Santee, and P. Bernath
Atmos. Chem. Phys., 14, 6545–6555, https://doi.org/10.5194/acp-14-6545-2014, https://doi.org/10.5194/acp-14-6545-2014, 2014
M. Rex, I. Wohltmann, T. Ridder, R. Lehmann, K. Rosenlof, P. Wennberg, D. Weisenstein, J. Notholt, K. Krüger, V. Mohr, and S. Tegtmeier
Atmos. Chem. Phys., 14, 4827–4841, https://doi.org/10.5194/acp-14-4827-2014, https://doi.org/10.5194/acp-14-4827-2014, 2014
M. von Hobe, S. Bekki, S. Borrmann, F. Cairo, F. D'Amato, G. Di Donfrancesco, A. Dörnbrack, A. Ebersoldt, M. Ebert, C. Emde, I. Engel, M. Ern, W. Frey, S. Genco, S. Griessbach, J.-U. Grooß, T. Gulde, G. Günther, E. Hösen, L. Hoffmann, V. Homonnai, C. R. Hoyle, I. S. A. Isaksen, D. R. Jackson, I. M. Jánosi, R. L. Jones, K. Kandler, C. Kalicinsky, A. Keil, S. M. Khaykin, F. Khosrawi, R. Kivi, J. Kuttippurath, J. C. Laube, F. Lefèvre, R. Lehmann, S. Ludmann, B. P. Luo, M. Marchand, J. Meyer, V. Mitev, S. Molleker, R. Müller, H. Oelhaf, F. Olschewski, Y. Orsolini, T. Peter, K. Pfeilsticker, C. Piesch, M. C. Pitts, L. R. Poole, F. D. Pope, F. Ravegnani, M. Rex, M. Riese, T. Röckmann, B. Rognerud, A. Roiger, C. Rolf, M. L. Santee, M. Scheibe, C. Schiller, H. Schlager, M. Siciliani de Cumis, N. Sitnikov, O. A. Søvde, R. Spang, N. Spelten, F. Stordal, O. Sumińska-Ebersoldt, A. Ulanovski, J. Ungermann, S. Viciani, C. M. Volk, M. vom Scheidt, P. von der Gathen, K. Walker, T. Wegner, R. Weigel, S. Weinbruch, G. Wetzel, F. G. Wienhold, I. Wohltmann, W. Woiwode, I. A. K. Young, V. Yushkov, B. Zobrist, and F. Stroh
Atmos. Chem. Phys., 13, 9233–9268, https://doi.org/10.5194/acp-13-9233-2013, https://doi.org/10.5194/acp-13-9233-2013, 2013
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 | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Measurement report: Elevated atmospheric ammonia may promote particle pH and HONO formation – insights from the COVID-19 pandemic
Measurement report: Vertical and temporal variability in the near-surface ozone production rate and sensitivity in an urban area in the Pearl River Delta region, China
Elevated oxidized mercury in the free troposphere: analytical advances and application at a remote continental mountaintop site
Using observed urban NOx sinks to constrain VOC reactivity and the ozone and radical budget in the Seoul Metropolitan Area
Real-world emission characteristics of VOCs from typical cargo ships and their potential contributions to secondary organic aerosol and O3 under low-sulfur fuel policies
NO3 reactivity during a summer period in a temperate forest below and above the canopy
The role of oceanic ventilation and terrestrial outflow in atmospheric non-methane hydrocarbons over the Chinese marginal seas
Concentration and source changes of nitrous acid (HONO) during the COVID-19 lockdown in Beijing
Characteristics and sources of nonmethane volatile organic compounds (NMVOCs) and O3–NOx–NMVOC relationships in Zhengzhou, China
Deciphering anthropogenic and biogenic contributions to selected non-methane volatile organic compound emissions in an urban area
Emission characteristics of reactive organic gases (ROGs) from industrial volatile chemical products (VCPs) in the Pearl River Delta (PRD), China
Measurement report: Enhanced photochemical formation of formic and isocyanic acids in urban regions aloft – insights from tower-based online gradient measurements
Sources of organic gases and aerosol particles and their roles in nighttime particle growth at a rural forested site in southwest Germany
Surface snow bromide and nitrate at Eureka, Canada, in early spring and implications for polar boundary layer chemistry
Opinion: Strengthening research in the Global South – atmospheric science opportunities in South America and Africa
Measurement Report: Urban Ammonia and Amines in Houston, Texas
Consistency evaluation of tropospheric ozone from ozonesonde and IAGOS aircraft observations: vertical distribution, ozonesonde types and station-airport distance
Investigating Carbonyl Compounds above the Amazon Rainforest using PTR-ToF-MS with NO+ Chemical Ionization
Shipping and algae emissions have a major impact on ambient air mixing ratios of non-methane hydrocarbons (NMHCs) and methanethiol on Utö Island in the Baltic Sea
Contribution of cooking emissions to the urban volatile organic compounds in Las Vegas, NV
Reanalysis of NOAA H2 observations: implications for the H2 budget
A large role of missing volatile organic compound reactivity from anthropogenic emissions in ozone pollution regulation
Measurement report: Insights into the chemical composition and origin of molecular clusters and potential precursor molecules present in the free troposphere over the southern Indian Ocean: observations from the Maïdo Observatory (2150 m a.s.l., Réunion)
Production of oxygenated volatile organic compounds from the ozonolysis of coastal seawater
Comment on “Transport of substantial stratospheric ozone to the surface by a dying typhoon and shallow convection” by Chen et al. (2022)
Observations of cyanogen bromide (BrCN) in the global troposphere and their relation to polar surface O3 destruction
CO2 and CO temporal variability over Mexico City from ground-based total column and surface measurements
Observations of the vertical distributions of summertime atmospheric pollutants in Nam Co: OH production and source analysis
Individual coal mine methane emissions constrained by eddy covariance measurements: low bias and missing sources
Measurement report: In-flight and ground-based measurements of nitrogen oxide emissions from latest generation jet engines and 100% sustainable aviation fuel
Measurement report: Observations of ground-level ozone concentration gradients perpendicular to the Lake Ontario shoreline
Biomass burning sources control ambient particulate matter but traffic and industrial sources control VOCs and secondary pollutant formation during extreme pollution events in Delhi
Quantifying SO2 oxidation pathways to atmospheric sulfate using stable sulfur and oxygen isotopes: laboratory simulation and field observation
Influences of downward transport and photochemistry on surface ozone over East Antarctica during austral summer: in situ observations and model simulations
Iodine oxoacids and their roles in sub-3 nm particle growth in polluted urban environments
Intensive photochemical oxidation in the marine atmosphere: evidence from direct radical measurements
Diurnal variations in oxygen and nitrogen isotopes of atmospheric nitrogen dioxide and nitrate: implications for tracing NOx oxidation pathways and emission sources
Multi-year observations of variable incomplete combustion in the New York megacity
Measurement report: Method for evaluating CO2 emissions from a cement plant using atmospheric δ(O2 ∕ N2) and CO2 measurements and its implication for future detection of CO2 capture signals
Aircraft-based mass balance estimate of methane emissions from offshore gas facilities in the southern North Sea
Measurement report: Sources, sinks and lifetime of NOX in a sub-urban temperate forest at night
Parameterizations of US wildfire and prescribed fire emission ratios and emission factors based on FIREX-AQ aircraft measurements
Measurement report: Atmospheric nitrate radical chemistry in the South China Sea influenced by the urban outflow of the Pearl River Delta
The interhemispheric gradient of SF6 in the upper troposphere
Weather regimes and the related atmospheric composition at a Pyrenean observatory characterized by hierarchical clustering of a 5-year data set
Tropospheric bromine monoxide vertical profiles retrieved across the Alaskan Arctic in springtime
Source apportionment of methane emissions from the Upper Silesian Coal Basin using isotopic signatures
Measurement report: Exchange fluxes of HONO over agricultural fields in the North China Plain
HONO chemistry at a suburban site during the EXPLORE-YRD campaign in 2018: formation mechanisms and impacts on O3 production
Evaluation of modelled climatologies of O3, CO, water vapour and NOy in the upper troposphere–lower stratosphere using regular in situ observations by passenger aircraft
Xinyuan Zhang, Lingling Wang, Nan Wang, Shuangliang Ma, Shenbo Wang, Ruiqin Zhang, Dong Zhang, Mingkai Wang, and Hongyu Zhang
Atmos. Chem. Phys., 24, 9885–9898, https://doi.org/10.5194/acp-24-9885-2024, https://doi.org/10.5194/acp-24-9885-2024, 2024
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This study highlights the importance of the redox reaction of NO2 with SO2 based on actual atmospheric observations. The particle pH in future China is expected to rise steadily. Consequently, this reaction could become a significant source of HONO in China. Therefore, it is crucial to coordinate the control of SO2, NOx, and NH3 emissions to avoid a rapid increase in the particle pH.
Jun Zhou, Chunsheng Zhang, Aiming Liu, Bin Yuan, Yan Wang, Wenjie Wang, Jie-Ping Zhou, Yixin Hao, Xiao-Bing Li, Xianjun He, Xin Song, Yubin Chen, Suxia Yang, Shuchun Yang, Yanfeng Wu, Bin Jiang, Shan Huang, Junwen Liu, Yuwen Peng, Jipeng Qi, Minhui Deng, Bowen Zhong, Yibo Huangfu, and Min Shao
Atmos. Chem. Phys., 24, 9805–9826, https://doi.org/10.5194/acp-24-9805-2024, https://doi.org/10.5194/acp-24-9805-2024, 2024
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In-depth understanding of the near-ground vertical variability in photochemical ozone (O3) formation is crucial for mitigating O3 pollution. Utilizing a self-built vertical observation system, a direct net photochemical O3 production rate detection system, and an observation-based model, we diagnosed the vertical distributions and formation mechanism of net photochemical O3 production rates and sensitivity in the Pearl River Delta region, one of the most O3-polluted areas in China.
Eleanor J. Derry, Tyler R. Elgiar, Taylor Y. Wilmot, Nicholas W. Hoch, Noah S. Hirshorn, Peter Weiss-Penzias, Christopher F. Lee, John C. Lin, A. Gannet Hallar, Rainer Volkamer, Seth N. Lyman, and Lynne E. Gratz
Atmos. Chem. Phys., 24, 9615–9643, https://doi.org/10.5194/acp-24-9615-2024, https://doi.org/10.5194/acp-24-9615-2024, 2024
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Mercury (Hg) is a globally distributed neurotoxic pollutant. Atmospheric deposition is the main source of Hg in ecosystems. However, measurement biases hinder understanding of the origins and abundance of the more bioavailable oxidized form. We used an improved, calibrated measurement system to study air mass composition and transport of atmospheric Hg at a remote mountaintop site in the central US. Oxidized Hg originated upwind in the low to middle free troposphere under clean, dry conditions.
Benjamin A. Nault, Katherine R. Travis, James H. Crawford, Donald R. Blake, Pedro Campuzano-Jost, Ronald C. Cohen, Joshua P. DiGangi, Glenn S. Diskin, Samuel R. Hall, L. Gregory Huey, Jose L. Jimenez, Kyung-Eun Kim, Young Ro Lee, Isobel J. Simpson, Kirk Ullmann, and Armin Wisthaler
Atmos. Chem. Phys., 24, 9573–9595, https://doi.org/10.5194/acp-24-9573-2024, https://doi.org/10.5194/acp-24-9573-2024, 2024
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Ozone (O3) is a pollutant formed from the reactions of gases emitted from various sources. In urban areas, the density of human activities can increase the O3 formation rate (P(O3)), thus impacting air quality and health. Observations collected over Seoul, South Korea, are used to constrain P(O3). A high local P(O3) was found; however, local P(O3) was partly reduced due to compounds typically ignored. These observations also provide constraints for unmeasured compounds that will impact P(O3).
Fan Zhang, Binyu Xiao, Zeyu Liu, Yan Zhang, Chongguo Tian, Rui Li, Can Wu, Yali Lei, Si Zhang, Xinyi Wan, Yubao Chen, Yong Han, Min Cui, Cheng Huang, Hongli Wang, Yingjun Chen, and Gehui Wang
Atmos. Chem. Phys., 24, 8999–9017, https://doi.org/10.5194/acp-24-8999-2024, https://doi.org/10.5194/acp-24-8999-2024, 2024
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Mandatory use of low-sulfur fuel due to global sulfur limit regulations means large uncertainties in volatile organic compound (VOC) emissions. On-board tests of VOCs from nine cargo ships in China were carried out. Results showed that switching from heavy-fuel oil to diesel increased emission factor VOCs by 48 % on average, enhancing O3 and the secondary organic aerosol formation potential. Thus, implementing a global ultra-low-sulfur oil policy needs to be optimized in the near future.
Patrick Dewald, Tobias Seubert, Simone T. Andersen, Gunther N. T. E. Türk, Jan Schuladen, Max R. McGillen, Cyrielle Denjean, Jean-Claude Etienne, Olivier Garrouste, Marina Jamar, Sergio Harb, Manuela Cirtog, Vincent Michoud, Mathieu Cazaunau, Antonin Bergé, Christopher Cantrell, Sebastien Dusanter, Bénédicte Picquet-Varrault, Alexandre Kukui, Chaoyang Xue, Abdelwahid Mellouki, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 24, 8983–8997, https://doi.org/10.5194/acp-24-8983-2024, https://doi.org/10.5194/acp-24-8983-2024, 2024
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In the scope of a field campaign in a suburban forest near Paris in the summer of 2022, we measured the reactivity of the nitrate radical NO3 towards biogenic volatile organic compounds (BVOCs; e.g. monoterpenes) mainly below but also above the canopy. NO3 reactivity was the highest during nights with strong temperature inversions and decreased strongly with height. Reactions with BVOCs were the main removal process of NO3 throughout the diel cycle below the canopy.
Jian Wang, Lei Xue, Qianyao Ma, Feng Xu, Gaobin Xu, Shibo Yan, Jiawei Zhang, Jianlong Li, Honghai Zhang, Guiling Zhang, and Zhaohui Chen
Atmos. Chem. Phys., 24, 8721–8736, https://doi.org/10.5194/acp-24-8721-2024, https://doi.org/10.5194/acp-24-8721-2024, 2024
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This study investigated the distribution and sources of non-methane hydrocarbons (NMHCs) in the lower atmosphere over the marginal seas of China. NMHCs, a subset of volatile organic compounds (VOCs), play a crucial role in atmospheric chemistry. Derived from systematic atmospheric sampling in coastal cities and marginal sea regions, this study offers valuable insights into the interaction between land and sea in shaping offshore atmospheric NMHCs.
Yusheng Zhang, Feixue Zheng, Zemin Feng, Chaofan Lian, Weigang Wang, Xiaolong Fan, Wei Ma, Zhuohui Lin, Chang Li, Gen Zhang, Chao Yan, Ying Zhang, Veli-Matti Kerminen, Federico Bianch, Tuukka Petäjä, Juha Kangasluoma, Markku Kulmala, and Yongchun Liu
Atmos. Chem. Phys., 24, 8569–8587, https://doi.org/10.5194/acp-24-8569-2024, https://doi.org/10.5194/acp-24-8569-2024, 2024
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The nitrous acid (HONO) budget was validated during a COVID-19 lockdown event. The main conclusions are (1) HONO concentrations showed a significant decrease from 0.97 to 0.53 ppb during lockdown; (2) vehicle emissions accounted for 53 % of nighttime sources, with the heterogeneous conversion of NO2 on ground surfaces more important than aerosol; and (3) the dominant daytime source shifted from the homogenous reaction between NO and OH (51 %) to nitrate photolysis (53 %) during lockdown.
Dong Zhang, Xiao Li, Minghao Yuan, Yifei Xu, Qixiang Xu, Fangcheng Su, Shenbo Wang, and Ruiqin Zhang
Atmos. Chem. Phys., 24, 8549–8567, https://doi.org/10.5194/acp-24-8549-2024, https://doi.org/10.5194/acp-24-8549-2024, 2024
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The increasing concentration of O3 precursors and unfavorable meteorological conditions are key factors in the formation of O3 pollution in Zhengzhou. Vehicular exhausts (28 %), solvent usage (27 %), and industrial production (22 %) are identified as the main sources of NMVOCs. Moreover, O3 formation in Zhengzhou is found to be in an anthropogenic volatile organic compound (AVOC)-limited regime. Thus, to reduce O3 formation, a minimum AVOCs / NOx reduction ratio ≥ 3 : 1 is recommended.
Arianna Peron, Martin Graus, Marcus Striednig, Christian Lamprecht, Georg Wohlfahrt, and Thomas Karl
Atmos. Chem. Phys., 24, 7063–7083, https://doi.org/10.5194/acp-24-7063-2024, https://doi.org/10.5194/acp-24-7063-2024, 2024
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The anthropogenic fraction of non-methane volatile organic compound (NMVOC) emissions associated with biogenic sources (e.g., terpenes) is investigated based on eddy covariance observations. The anthropogenic fraction of terpene emissions is strongly dependent on season. When analyzing volatile chemical product (VCP) emissions in urban environments, we caution that observations from short-term campaigns might over-/underestimate their significance depending on local and seasonal circumstances.
Sihang Wang, Bin Yuan, Xianjun He, Ru Cui, Xin Song, Yubin Chen, Caihong Wu, Chaomin Wang, Yibo Huangfu, Xiao-Bing Li, Boguang Wang, and Min Shao
Atmos. Chem. Phys., 24, 7101–7121, https://doi.org/10.5194/acp-24-7101-2024, https://doi.org/10.5194/acp-24-7101-2024, 2024
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Emissions of reactive organic gases from industrial volatile chemical product sources are measured. There are large differences among these industrial sources. We show that oxygenated species account for significant contributions to reactive organic gas emissions, especially for industrial sources utilizing water-borne chemicals.
Qing Yang, Xiao-Bing Li, Bin Yuan, Xiaoxiao Zhang, Yibo Huangfu, Lei Yang, Xianjun He, Jipeng Qi, and Min Shao
Atmos. Chem. Phys., 24, 6865–6882, https://doi.org/10.5194/acp-24-6865-2024, https://doi.org/10.5194/acp-24-6865-2024, 2024
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Online vertical gradient measurements of formic and isocyanic acids were made based on a 320 m tower in a megacity. Vertical variations and sources of the two acids were analyzed in this study. We find that formic and isocyanic acids exhibited positive vertical gradients and were mainly contributed by photochemical formations. The formation of formic and isocyanic acids was also significantly enhanced in urban regions aloft.
Junwei Song, Harald Saathoff, Feng Jiang, Linyu Gao, Hengheng Zhang, and Thomas Leisner
Atmos. Chem. Phys., 24, 6699–6717, https://doi.org/10.5194/acp-24-6699-2024, https://doi.org/10.5194/acp-24-6699-2024, 2024
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This study presents concurrent online measurements of organic gas and particles (VOCs and OA) at a forested site in summer. Both VOCs and OA were largely contributed by oxygenated organic compounds. Semi-volatile oxygenated OA and organic nitrate formed from monoterpenes and sesquiterpenes contributed significantly to nighttime particle growth. The results help us to understand the causes of nighttime particle growth regularly observed in summer in central European rural forested environments.
Xin Yang, Kimberly Strong, Alison S. Criscitiello, Marta Santos-Garcia, Kristof Bognar, Xiaoyi Zhao, Pierre Fogal, Kaley A. Walker, Sara M. Morris, and Peter Effertz
Atmos. Chem. Phys., 24, 5863–5886, https://doi.org/10.5194/acp-24-5863-2024, https://doi.org/10.5194/acp-24-5863-2024, 2024
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This study uses snow samples collected from a Canadian high Arctic site, Eureka, to demonstrate that surface snow in early spring is a net sink of atmospheric bromine and nitrogen. Surface snow bromide and nitrate are significantly correlated, indicating the oxidation of reactive nitrogen is accelerated by reactive bromine. In addition, we show evidence that snow photochemical release of reactive bromine is very weak, and its emission flux is much smaller than the deposition flux of bromide.
Rebecca M. Garland, Katye E. Altieri, Laura Dawidowski, Laura Gallardo, Aderiana Mbandi, Nestor Y. Rojas, and N'datchoh E. Touré
Atmos. Chem. Phys., 24, 5757–5764, https://doi.org/10.5194/acp-24-5757-2024, https://doi.org/10.5194/acp-24-5757-2024, 2024
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This opinion piece focuses on two geographical areas in the Global South where the authors are based that are underrepresented in atmospheric science. This opinion provides context on common challenges and constraints, with suggestions on how the community can address these. The focus is on the strengths of atmospheric science research in these regions. It is these strengths, we believe, that highlight the critical role of Global South researchers in the future of atmospheric science research.
Lee Tiszenkel, James Flynn, and Shan-Hu Lee
EGUsphere, https://doi.org/10.5194/egusphere-2024-1230, https://doi.org/10.5194/egusphere-2024-1230, 2024
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Ammonia and amines are important ingredients for aerosol formation in urban environments, but the measurements of these compounds are extremely challenging. Our observations show that urban ammonia and amines in Houston are emitted from urban sources and diurnal variations of their concentrations are governed by gas-to-particle conversion processes.
Honglei Wang, David W. Tarasick, Jane Liu, Herman G. J. Smit, Roeland Van Malderen, Lijuan Shen, and Tianliang Zhao
EGUsphere, https://doi.org/10.5194/egusphere-2024-1015, https://doi.org/10.5194/egusphere-2024-1015, 2024
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In this study, we identify 23 suitable pairs of sites in the WOUDC and IAGOS datasets from 1995 to 2021, compare the average vertical distribution of tropospheric O3 shown by ozonesonde and aircraft measurements, and analyze their differences by ozonesonde type and by station-airport distance.
Akima Ringsdorf, Achim Edtbauer, Bruna Holanda, Christopher Poehlker, Marta O. Sá, Alessandro Araújo, Jürgen Kesselmeier, Jos Lelieveld, and Jonathan Williams
EGUsphere, https://doi.org/10.5194/egusphere-2024-1210, https://doi.org/10.5194/egusphere-2024-1210, 2024
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We show the average height distribution of separately observed aldehydes and ketones over a day and discuss their rainforest-specific sources and sinks and their seasonal changes above the Amazon rainforest. Ketones have much longer atmospheric lifetimes than aldehydes, and thus different implications for atmospheric chemistry. However, they are commonly observed together, which we overcome by measuring with a NO+ chemical ionization mass spectrometer for the first time in the Amazon rainforest.
Heidi Hellén, Rostislav Kouznetsov, Kaisa Kraft, Jukka Seppälä, Mika Vestenius, Jukka-Pekka Jalkanen, Lauri Laakso, and Hannele Hakola
Atmos. Chem. Phys., 24, 4717–4731, https://doi.org/10.5194/acp-24-4717-2024, https://doi.org/10.5194/acp-24-4717-2024, 2024
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Mixing ratios of C2-C5 NMHCs and methanethiol were measured on an island in the Baltic Sea using an in situ gas chromatograph. Shipping emissions were found to be an important source of ethene, ethyne, propene, and benzene. High summertime mixing ratios of methanethiol and dependence of mixing ratios on seawater temperature and height indicated the biogenic origin to possibly be phytoplankton or macroalgae. These emissions may have a strong impact on SO2 production and new particle formation.
Matthew M. Coggon, Chelsea E. Stockwell, Lu Xu, Jeff Peischl, Jessica B. Gilman, Aaron Lamplugh, Henry J. Bowman, Kenneth Aikin, Colin Harkins, Qindan Zhu, Rebecca H. Schwantes, Jian He, Meng Li, Karl Seltzer, Brian McDonald, and Carsten Warneke
Atmos. Chem. Phys., 24, 4289–4304, https://doi.org/10.5194/acp-24-4289-2024, https://doi.org/10.5194/acp-24-4289-2024, 2024
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Residential and commercial cooking emits pollutants that degrade air quality. Here, ambient observations show that cooking is an important contributor to anthropogenic volatile organic compounds (VOCs) emitted in Las Vegas, NV. These emissions are not fully presented in air quality models, and more work may be needed to quantify emissions from important sources, such as commercial restaurants.
Fabien Paulot, Gabrielle Pétron, Andrew M. Crotwell, and Matteo B. Bertagni
Atmos. Chem. Phys., 24, 4217–4229, https://doi.org/10.5194/acp-24-4217-2024, https://doi.org/10.5194/acp-24-4217-2024, 2024
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New data from the National Oceanic and Atmospheric Administration show that hydrogen (H2) concentrations increased from 2010 to 2019, which is consistent with the simulated increase in H2 photochemical production (mainly from methane). But this cannot be reconciled with the expected decrease (increase) in H2 anthropogenic emissions (soil deposition) in the same period. This shows gaps in our knowledge of the H2 biogeochemical cycle that must be resolved to quantify the impact of higher H2 usage.
Wenjie Wang, Bin Yuan, Hang Su, Yafang Cheng, Jipeng Qi, Sihang Wang, Wei Song, Xinming Wang, Chaoyang Xue, Chaoqun Ma, Fengxia Bao, Hongli Wang, Shengrong Lou, and Min Shao
Atmos. Chem. Phys., 24, 4017–4027, https://doi.org/10.5194/acp-24-4017-2024, https://doi.org/10.5194/acp-24-4017-2024, 2024
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This study investigates the important role of unmeasured volatile organic compounds (VOCs) in ozone formation. Based on results in a megacity of China, we show that unmeasured VOCs can contribute significantly to ozone fomation and also influence the determination of ozone control strategy. Our results show that these unmeasured VOCs are mainly from human sources.
Romain Salignat, Matti Rissanen, Siddharth Iyer, Jean-Luc Baray, Pierre Tulet, Jean-Marc Metzger, Jérôme Brioude, Karine Sellegri, and Clémence Rose
Atmos. Chem. Phys., 24, 3785–3812, https://doi.org/10.5194/acp-24-3785-2024, https://doi.org/10.5194/acp-24-3785-2024, 2024
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Using mass spectrometry data collected at the Maïdo Observatory (2160 m a.s.l., Réunion), we provide the first detailed analysis of molecular cluster chemical composition specifically in the marine free troposphere. The abundance of the identified species is related both to in situ meteorological parameters and air mass history, which also provide insight into their origin. Our work makes an important contribution to documenting the chemistry and physics of the marine free troposphere.
Delaney B. Kilgour, Gordon A. Novak, Megan S. Claflin, Brian M. Lerner, and Timothy H. Bertram
Atmos. Chem. Phys., 24, 3729–3742, https://doi.org/10.5194/acp-24-3729-2024, https://doi.org/10.5194/acp-24-3729-2024, 2024
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Laboratory experiments with seawater mimics suggest ozone deposition to the surface ocean can be a source of reactive carbon to the marine atmosphere. We conduct both field and laboratory measurements to assess abiotic VOC composition and yields from ozonolysis of real surface seawater. We show that C5–C11 aldehydes contribute to the observed VOC emission flux. We estimate that VOCs generated by the ozonolysis of surface seawater are competitive with biological VOC production and emission.
Xiangdong Zheng, Wen Yang, Yuting Sun, Chunmei Geng, Yingying Liu, and Xiaobin Xu
Atmos. Chem. Phys., 24, 3759–3768, https://doi.org/10.5194/acp-24-3759-2024, https://doi.org/10.5194/acp-24-3759-2024, 2024
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Chen et al. (2022) attributed the nocturnal ozone enhancement (NOE) during the night of 31 July 2021 in the North China Plain (NCP) to "the direct stratospheric intrusion to reach the surface". We analyzed in situ data from the NCP. Our results do not suggest that there was a significant impact from the stratosphere on surface ozone during the NOE. We argue that the NOE was not caused by stratospheric intrusion but originated from fresh photochemical production in the lower troposphere.
James M. Roberts, Siyuan Wang, Patrick R. Veres, J. Andrew Neuman, Michael A. Robinson, Ilann Bourgeois, Jeff Peischl, Thomas B. Ryerson, Chelsea R. Thompson, Hannah M. Allen, John D. Crounse, Paul O. Wennberg, Samuel R. Hall, Kirk Ullmann, Simone Meinardi, Isobel J. Simpson, and Donald Blake
Atmos. Chem. Phys., 24, 3421–3443, https://doi.org/10.5194/acp-24-3421-2024, https://doi.org/10.5194/acp-24-3421-2024, 2024
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We measured cyanogen bromide (BrCN) in the troposphere for the first time. BrCN is a product of the same active bromine chemistry that destroys ozone and removes mercury in polar surface environments and is a previously unrecognized sink for active Br compounds. BrCN has an apparent lifetime against heterogeneous loss in the range 1–10 d, so it serves as a cumulative marker of Br-radical chemistry. Accounting for BrCN chemistry is an important part of understanding polar Br cycling.
Noémie Taquet, Wolfgang Stremme, María Eugenia Gonzalez del Castillo, Victor Almanza, Alejandro Bezanilla, Olivier Laurent, Carlos Alberti, Frank Hase, Michel Ramonet, Thomas Lauvaux, Ke Che, and Michel Grutter
EGUsphere, https://doi.org/10.5194/egusphere-2024-512, https://doi.org/10.5194/egusphere-2024-512, 2024
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We studied the variability of CO and CO2 and their ratio over Mexico City from long-term time-resolved FTIR solar absorption and surface measurements. Using the average intraday CO growth rate from total columns and TROPOMI measurements, we additionally estimate the interannual variability of CO and CO2 anthropogenic emissions of the City and relate it to the main influencing events of the last decade, such as the COVID-19 lock-down.
Chengzhi Xing, Cheng Liu, Chunxiang Ye, Xiangguang Ji, Jingkai Xue, Jinping Ou, Hongyu Wu, and Qihou Hu
EGUsphere, https://doi.org/10.5194/egusphere-2024-461, https://doi.org/10.5194/egusphere-2024-461, 2024
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We learned the contributions of O3 and HONO to the production rates of OH in vertical space on the TP. A new insight was offered: the contributions of HONO and O3 to the production rates of OH on the TP are even greater than at lower-altitudes areas. This study will enrich the new understanding of vertical distribution of atmospheric components and explained the strong AOC on the TP.
Kai Qin, Wei Hu, Qin He, Fan Lu, and Jason Blake Cohen
Atmos. Chem. Phys., 24, 3009–3028, https://doi.org/10.5194/acp-24-3009-2024, https://doi.org/10.5194/acp-24-3009-2024, 2024
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We compute CH4 emissions and uncertainty on a mine-by-mine basis, including underground, overground, and abandoned mines. Mine-by-mine gas and flux data and 30 min observations from a flux tower located next to a mine shaft are integrated. The observed variability and bias correction are propagated over the emissions dataset, demonstrating that daily observations may not cover the range of variability. Comparisons show both an emissions magnitude and spatial mismatch with current inventories.
Theresa Harlass, Rebecca Dischl, Stefan Kaufmann, Raphael Märkl, Daniel Sauer, Monika Scheibe, Paul Stock, Tiziana Bräuer, Andreas Dörnbrack, Anke Roiger, Hans Schlager, Ulrich Schumann, Tobias Schripp, Tobias Grein, Linda Bondorf, Charles Renard, Maxime Gauthier, Mark Johnson, Darren Luff, Paul Madden, Peter Swann, Denise Ahrens, Reetu Sallinen, and Christiane Voigt
EGUsphere, https://doi.org/10.5194/egusphere-2024-454, https://doi.org/10.5194/egusphere-2024-454, 2024
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Emissions from aircraft have a direct impact on our climate. Here, we present airborne and ground based measurement data of nitrogen oxides which were collected in the exhaust of an Airbus aircraft. We study the impact of burning fossil and sustainable aviation fuel on nitrogen oxide emissions at different engine settings related to combustor temperature, pressure and fuel flow. Further, we compare observations with engine emission models.
Yao Yan Huang and D. James Donaldson
Atmos. Chem. Phys., 24, 2387–2398, https://doi.org/10.5194/acp-24-2387-2024, https://doi.org/10.5194/acp-24-2387-2024, 2024
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Ground-level ozone interacts at the lake–land boundary; this is important to our understanding and modelling of atmospheric chemistry and air pollution in the lower atmosphere. We show that a steep ozone gradient occurs year-round moving inland up to 1 km from the lake and that this gradient is influenced by seasonal factors on the local land environment, where more rural areas are more greatly affected seasonally.
Arpit Awasthi, Baerbel Sinha, Haseeb Hakkim, Sachin Mishra, Varkrishna Mummidivarapu, Gurmanjot Singh, Sachin D. Ghude, Vijay Kumar Soni, Narendra Nigam, Vinayak Sinha, and Madhavan N. Rajeevan
EGUsphere, https://doi.org/10.5194/egusphere-2024-501, https://doi.org/10.5194/egusphere-2024-501, 2024
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Our study uses a data set of 111 VOCs from a PTR-ToF-MS 10k, PM10 and PM2.5 in a PMF source-receptor model to resolve 11 pollution sources validated with chemical fingerprints collected at the source. Crop residue burning and heating contribute ~50 % of the PM, while traffic and industrial emissions dominate the gas-phase VOCs burden and SOA formation potential (>60 %). Non-tailpipe emissions from CNG powered commercial vehicles dominate the transport sector contribution to the PM burden.
Ziyan Guo, Keding Lu, Pengxiang Qiu, Mingyi Xu, and Zhaobing Guo
Atmos. Chem. Phys., 24, 2195–2205, https://doi.org/10.5194/acp-24-2195-2024, https://doi.org/10.5194/acp-24-2195-2024, 2024
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The formation of secondary sulfate needs to be further explored. In this work, we simultaneously measured sulfur and oxygen isotopic compositions to gain an increased understanding of specific sulfate formation processes. The results indicated that secondary sulfate was mainly ascribed to SO2 homogeneous oxidation by OH radicals and heterogeneous oxidation by H2O2 and Fe3+ / O2. This study is favourable for deeply investigating the sulfur cycle in the atmosphere.
Imran A. Girach, Narendra Ojha, Prabha R. Nair, Kandula V. Subrahmanyam, Neelakantan Koushik, Mohammed M. Nazeer, Nadimpally Kiran Kumar, Surendran Nair Suresh Babu, Jos Lelieveld, and Andrea Pozzer
Atmos. Chem. Phys., 24, 1979–1995, https://doi.org/10.5194/acp-24-1979-2024, https://doi.org/10.5194/acp-24-1979-2024, 2024
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We investigate surface ozone variability in East Antarctica based on measurements and EMAC global model simulations during austral summer. Nearly half of the surface ozone is found to be of stratospheric origin. The east coast of Antarctica acts as a stronger sink of ozone than surrounding regions. Photochemical loss of ozone is counterbalanced by downward transport of ozone. The study highlights the intertwined role of chemistry and dynamics in governing ozone variations over East Antarctica.
Ying Zhang, Duzitian Li, Xu-Cheng He, Wei Nie, Chenjuan Deng, Runlong Cai, Yuliang Liu, Yishuo Guo, Chong Liu, Yiran Li, Liangduo Chen, Yuanyuan Li, Chenjie Hua, Tingyu Liu, Zongcheng Wang, Jiali Xie, Lei Wang, Tuukka Petäjä, Federico Bianchi, Ximeng Qi, Xuguang Chi, Pauli Paasonen, Yongchun Liu, Chao Yan, Jingkun Jiang, Aijun Ding, and Markku Kulmala
Atmos. Chem. Phys., 24, 1873–1893, https://doi.org/10.5194/acp-24-1873-2024, https://doi.org/10.5194/acp-24-1873-2024, 2024
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This study conducts a long-term observation of gaseous iodine oxoacids in two Chinese megacities, revealing their ubiquitous presence with peak concentrations (up to 0.1 pptv) in summer. Our analysis suggests a mix of terrestrial and marine sources for iodine. Additionally, iodic acid is identified as a notable contributor to sub-3 nm particle growth and particle survival probability.
Guoxian Zhang, Renzhi Hu, Pinhua Xie, Changjin Hu, Xiaoyan Liu, Liujun Zhong, Haotian Cai, Bo Zhu, Shiyong Xia, Xiaofeng Huang, Xin Li, and Wenqing Liu
Atmos. Chem. Phys., 24, 1825–1839, https://doi.org/10.5194/acp-24-1825-2024, https://doi.org/10.5194/acp-24-1825-2024, 2024
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Comprehensive observation of HOx radicals was conducted at a coastal site in the Pearl River Delta. Radical chemistry was influenced by different air masses in a time-dependent way. Land mass promotes a more active photochemical process, with daily averages of 7.1 × 106 and 5.2 × 108 cm−3 for OH and HO2 respectively. The rapid oxidation process was accompanied by a higher diurnal HONO concentration, which influences the ozone-sensitive system and eventually magnifies the background ozone.
Sarah Albertin, Joël Savarino, Slimane Bekki, Albane Barbero, Roberto Grilli, Quentin Fournier, Irène Ventrillard, Nicolas Caillon, and Kathy Law
Atmos. Chem. Phys., 24, 1361–1388, https://doi.org/10.5194/acp-24-1361-2024, https://doi.org/10.5194/acp-24-1361-2024, 2024
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This study reports the first simultaneous records of oxygen (Δ17O) and nitrogen (δ15N) isotopes in nitrogen dioxide (NO2) and nitrate (NO3−). These data are combined with atmospheric observations to explore sub-daily N reactive chemistry and quantify N fractionation effects in an Alpine winter city. The results highlight the necessity of using Δ17O and δ15N in both NO2 and NO3− to avoid biased estimations of NOx sources and fates from NO3− isotopic records in urban winter environments.
Luke D. Schiferl, Cong Cao, Bronte Dalton, Andrew Hallward-Driemeier, Ricardo Toledo-Crow, and Róisín Commane
EGUsphere, https://doi.org/10.5194/egusphere-2024-83, https://doi.org/10.5194/egusphere-2024-83, 2024
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Carbon monoxide (CO) is an air pollutant and an important indicator of the incomplete combustion of fossil fuels in cities. Using four years of winter and spring observations in New York City, we found that both the magnitude and variability of CO from the metropolitan area are greater than expected. Transportation emissions cannot explain the missing and variable CO, which points to energy from buildings as a likely underappreciated source of urban air pollution and greenhouse gas emissions.
Shigeyuki Ishidoya, Kazuhiro Tsuboi, Hiroaki Kondo, Kentaro Ishijima, Nobuyuki Aoki, Hidekazu Matsueda, and Kazuyuki Saito
Atmos. Chem. Phys., 24, 1059–1077, https://doi.org/10.5194/acp-24-1059-2024, https://doi.org/10.5194/acp-24-1059-2024, 2024
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A method evaluating techniques for carbon neutrality, such as carbon capture and storage (CCS), is important. This study presents a method to evaluate CO2 emissions from a cement plant based on atmospheric O2 and CO2 measurements. The method will also be useful for evaluating CO2 capture from flue gas at CCS plants, since the plants remove CO2 from the atmosphere without causing any O2 changes, just as cement plants do, differing only in the direction of CO2 exchange with the atmosphere.
Magdalena Pühl, Anke Roiger, Alina Fiehn, Alan M. Gorchov Negron, Eric A. Kort, Stefan Schwietzke, Ignacio Pisso, Amy Foulds, James Lee, James L. France, Anna E. Jones, Dave Lowry, Rebecca E. Fisher, Langwen Huang, Jacob Shaw, Prudence Bateson, Stephen Andrews, Stuart Young, Pamela Dominutti, Tom Lachlan-Cope, Alexandra Weiss, and Grant Allen
Atmos. Chem. Phys., 24, 1005–1024, https://doi.org/10.5194/acp-24-1005-2024, https://doi.org/10.5194/acp-24-1005-2024, 2024
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In April–May 2019 we carried out an airborne field campaign in the southern North Sea with the aim of studying methane emissions of offshore gas installations. We determined methane emissions from elevated methane measured downstream of the sampled installations. We compare our measured methane emissions with estimated methane emissions from national and global annual inventories. As a result, we find inconsistencies of inventories and large discrepancies between measurements and inventories.
Simone T. Andersen, Max R. McGillen, Chaoyang Xue, Tobias Seubert, Patrick Dewald, Gunther N. T. E. Türk, Jan Schuladen, Cyrielle Denjean, Jean-Claude Etienne, Olivier Garrouste, Marina Jamar, Sergio Harb, Manuela Cirtog, Vincent Michoud, Mathieu Cazaunau, Antonin Bergé, Christopher Cantrell, Sebastien Dusanter, Bénédicte Picquet-Varrault, Alexandre Kukui, Abdelwahid Mellouki, Lucy J. Carpenter, Jos Lelieveld, and John N. Crowley
EGUsphere, https://doi.org/10.5194/egusphere-2023-2848, https://doi.org/10.5194/egusphere-2023-2848, 2024
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Through measurements of various trace gases in a sub-urban forest near Paris in the summer of 2022 we were able to gain insight into the sources and sinks of NOx (NO+NO2) with a special focus on their nighttime chemical/physical loss processes. NO was observed as a result of nighttime soil emissions when ozone levels were strongly depleted by deposition. NO oxidation products were not observed at night indicating that soil and/or foliar surfaces are an efficient sink of reactive nitrogen.
Georgios I. Gkatzelis, Matthew M. Coggon, Chelsea E. Stockwell, Rebecca S. Hornbrook, Hannah Allen, Eric C. Apel, Megan M. Bela, Donald R. Blake, Ilann Bourgeois, Steven S. Brown, Pedro Campuzano-Jost, Jason M. St. Clair, James H. Crawford, John D. Crounse, Douglas A. Day, Joshua P. DiGangi, Glenn S. Diskin, Alan Fried, Jessica B. Gilman, Hongyu Guo, Johnathan W. Hair, Hannah S. Halliday, Thomas F. Hanisco, Reem Hannun, Alan Hills, L. Gregory Huey, Jose L. Jimenez, Joseph M. Katich, Aaron Lamplugh, Young Ro Lee, Jin Liao, Jakob Lindaas, Stuart A. McKeen, Tomas Mikoviny, Benjamin A. Nault, J. Andrew Neuman, John B. Nowak, Demetrios Pagonis, Jeff Peischl, Anne E. Perring, Felix Piel, Pamela S. Rickly, Michael A. Robinson, Andrew W. Rollins, Thomas B. Ryerson, Melinda K. Schueneman, Rebecca H. Schwantes, Joshua P. Schwarz, Kanako Sekimoto, Vanessa Selimovic, Taylor Shingler, David J. Tanner, Laura Tomsche, Krystal T. Vasquez, Patrick R. Veres, Rebecca Washenfelder, Petter Weibring, Paul O. Wennberg, Armin Wisthaler, Glenn M. Wolfe, Caroline C. Womack, Lu Xu, Katherine Ball, Robert J. Yokelson, and Carsten Warneke
Atmos. Chem. Phys., 24, 929–956, https://doi.org/10.5194/acp-24-929-2024, https://doi.org/10.5194/acp-24-929-2024, 2024
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This study reports emissions of gases and particles from wildfires. These emissions are related to chemical proxies that can be measured by satellite and incorporated into models to improve predictions of wildfire impacts on air quality and climate.
Jie Wang, Haichao Wang, Yee Jun Tham, Lili Ming, Zelong Zheng, Guizhen Fang, Cuizhi Sun, Zhenhao Ling, Jun Zhao, and Shaojia Fan
Atmos. Chem. Phys., 24, 977–992, https://doi.org/10.5194/acp-24-977-2024, https://doi.org/10.5194/acp-24-977-2024, 2024
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Many works report NO3 chemistry in inland regions while less target marine regions. We measured N2O5 and related species on a typical island and found intensive nighttime chemistry and rapid NO3 loss. NO contributed significantly to NO3 loss despite its sub-ppbv level, suggesting nocturnal NO3 reactions would be largely enhanced once free from NO emissions in the open ocean. This highlights the strong influences of urban outflow on downward marine areas in terms of nighttime chemistry.
Tanja J. Schuck, Johannes Degen, Eric Hintsa, Peter Hoor, Markus Jesswein, Timo Keber, Daniel Kunkel, Fred Moore, Florian Obersteiner, Matt Rigby, Thomas Wagenhäuser, Luke M. Western, Andreas Zahn, and Andreas Engel
Atmos. Chem. Phys., 24, 689–705, https://doi.org/10.5194/acp-24-689-2024, https://doi.org/10.5194/acp-24-689-2024, 2024
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We study the interhemispheric gradient of sulfur hexafluoride (SF6), a strong long-lived greenhouse gas. Its emissions are stronger in the Northern Hemisphere; therefore, mixing ratios in the Southern Hemisphere lag behind. Comparing the observations to a box model, the model predicts air in the Southern Hemisphere to be older. For a better agreement, the emissions used as model input need to be increased (and their spatial pattern changed), and we need to modify north–south transport.
Jérémy Gueffier, François Gheusi, Marie Lothon, Véronique Pont, Alban Philibert, Fabienne Lohou, Solène Derrien, Yannick Bezombes, Gilles Athier, Yves Meyerfeld, Antoine Vial, and Emmanuel Leclerc
Atmos. Chem. Phys., 24, 287–316, https://doi.org/10.5194/acp-24-287-2024, https://doi.org/10.5194/acp-24-287-2024, 2024
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This study investigates the link between weather regime and atmospheric composition at a Pyrenean observatory. Five years of meteorological data were synchronized on a daily basis and then, using a clustering method, separated into six groups of observation days, with most showing marked characteristics of different weather regimes (fair and disturbed weather, winter windstorms, foehn). Statistical differences in gas and particle concentrations appeared between the groups and are discussed.
Nathaniel Brockway, Peter K. Peterson, Katja Bigge, Kristian D. Hajny, Paul B. Shepson, Kerri A. Pratt, Jose D. Fuentes, Tim Starn, Robert Kaeser, Brian H. Stirm, and William R. Simpson
Atmos. Chem. Phys., 24, 23–40, https://doi.org/10.5194/acp-24-23-2024, https://doi.org/10.5194/acp-24-23-2024, 2024
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Bromine monoxide (BrO) strongly affects atmospheric chemistry in the springtime Arctic, yet there are still many uncertainties around its sources and recycling, particularly in the context of a rapidly changing Arctic. In this study, we observed BrO as a function of altitude above the Alaskan Arctic. We found that BrO was often most concentrated near the ground, confirming the ability of snow to produce and recycle reactive bromine, and identified four common vertical distributions of BrO.
Alina Fiehn, Maximilian Eckl, Julian Kostinek, Michał Gałkowski, Christoph Gerbig, Michael Rothe, Thomas Röckmann, Malika Menoud, Hossein Maazallahi, Martina Schmidt, Piotr Korbeń, Jarosław Neçki, Mila Stanisavljević, Justyna Swolkień, Andreas Fix, and Anke Roiger
Atmos. Chem. Phys., 23, 15749–15765, https://doi.org/10.5194/acp-23-15749-2023, https://doi.org/10.5194/acp-23-15749-2023, 2023
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During the CoMet mission in the Upper Silesian Coal Basin (USCB) ground-based and airborne air samples were taken and analyzed for the isotopic composition of CH4 to derive the mean signature of the USCB and source signatures of individual coal mines. Using δ2H signatures, the biogenic emissions from the USCB account for 15 %–50 % of total emissions, which is underestimated in common emission inventories. This demonstrates the importance of δ2H-CH4 observations for methane source apportionment.
Yifei Song, Chaoyang Xue, Yuanyuan Zhang, Pengfei Liu, Fengxia Bao, Xuran Li, and Yujing Mu
Atmos. Chem. Phys., 23, 15733–15747, https://doi.org/10.5194/acp-23-15733-2023, https://doi.org/10.5194/acp-23-15733-2023, 2023
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We present measurements of HONO flux and related parameters over an agricultural field during a whole growing season of summer maize. This dataset allows studies on the characteristics and influencing factors of soil HONO emissions, determination of HONO emission factors, estimation of total HONO emissions at a national scale, and the discussion on future environmental policies in terms of mitigating regional air pollution.
Can Ye, Keding Lu, Xuefei Ma, Wanyi Qiu, Shule Li, Xinping Yang, Chaoyang Xue, Tianyu Zhai, Yuhan Liu, Xuan Li, Yang Li, Haichao Wang, Zhaofeng Tan, Xiaorui Chen, Huabin Dong, Limin Zeng, Min Hu, and Yuanhang Zhang
Atmos. Chem. Phys., 23, 15455–15472, https://doi.org/10.5194/acp-23-15455-2023, https://doi.org/10.5194/acp-23-15455-2023, 2023
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In this study, combining comprehensive field measurements and a box model, we found NO2 conversion on the ground surface was the most important source for HONO production among the proposed heterogeneous and gas-phase HONO sources. In addition, HONO was found to evidently enhance O3 production and aggravate O3 pollution in summer in China. Our study improved our understanding of the relative importance of different HONO sources and the crucial role of HONO in O3 formation in polluted areas.
Yann Cohen, Didier Hauglustaine, Bastien Sauvage, Susanne Rohs, Patrick Konjari, Ulrich Bundke, Andreas Petzold, Valérie Thouret, Andreas Zahn, and Helmut Ziereis
Atmos. Chem. Phys., 23, 14973–15009, https://doi.org/10.5194/acp-23-14973-2023, https://doi.org/10.5194/acp-23-14973-2023, 2023
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The upper troposphere–lower stratosphere (UTLS) is a key region regarding the lower atmospheric composition. This study consists of a comprehensive evaluation of an up-to-date chemistry–climate model in this layer, using regular in situ measurements based on passenger aircraft. For this purpose, a specific software (Interpol-IAGOS) has been updated and made publicly available. The model reproduces the carbon monoxide peaks due to biomass burning over the continental tropics particularly well.
Cited articles
Anderson, D. C., Nicely, J. M., Salawitch, R. J., Canty, T. P., Dickerson, R. R., Hanisco, T. F., Wolfe, G. M., Apel, E. C., Atlas, E., Bannan, T., Bauguitte, S., Blake, N. J., Bresch, J. F., Campos, T. L., Carpenter, L. J., Cohen, M. D., Evans, M., Fernandez, R. P., Kahn, B. H., Kinnison, D. E., Hall, S. R., Harris, N. R., Hornbrook, R. S., Lamarque, J.-F., Le Breton, M., Lee, J. D., Percival, C., Pfister, L., Pierce, R. B., Riemer, D. D., Saiz-Lopez, A., Stunder, B. J., Thompson, A. M., Ullmann, K., Vaughan, A., and Weinheimer, A. J.: A Pervasive Role for Biomass Burning in Tropical High Ozone/Low Water Structures, Nat. Commun., 7, 10267, https://doi.org/10.1038/ncomms10267, 2016. a, b
Ansmann, A., Wandinger, U., Riebesell, M., Weitkamp, C., and Michaelis, W.: Independent Measurement of Extinction and Backscatter Profiles in Cirrus Clouds by Using a Combined Raman Elastic-Backscatter Lidar, Appl. Optics, 31, 7113, https://doi.org/10.1364/AO.31.007113, 1992. a
Australian Bureau of Meteorology and CSIRO: Climate Variability, Extremes and Change in the Western Tropical Pacific: New Science and Updated Country Reports 2014, Centre for Australian Weather and Climate Research, Collingwood, Vic., ISBN 978-1-4863-0289-5, 2014. a
Brunamonti, S., Jorge, T., Oelsner, P., Hanumanthu, S., Singh, B. B., Kumar, K. R., Sonbawne, S., Meier, S., Singh, D., Wienhold, F. G., Luo, B. P., Boettcher, M., Poltera, Y., Jauhiainen, H., Kayastha, R., Karmacharya, J., Dirksen, R., Naja, M., Rex, M., Fadnavis, S., and Peter, T.: Balloon-borne measurements of temperature, water vapor, ozone and aerosol backscatter on the southern slopes of the Himalayas during StratoClim 2016–2017, Atmos. Chem. Phys., 18, 15937–15957, https://doi.org/10.5194/acp-18-15937-2018, 2018. a
Cairo, F., De Muro, M., Snels, M., Di Liberto, L., Bucci, S., Legras, B., Kottayil, A., Scoccione, A., and Ghisu, S.: Lidar observations of cirrus clouds in Palau (7∘33′ N, 134∘48′ E), Atmos. Chem. Phys., 21, 7947–7961, https://doi.org/10.5194/acp-21-7947-2021, 2021. a, b
Crawford, J. H., Davis, D. D., Chen, G., Bradshaw, J., Sandholm, S., Kondo, Y., Merrill, J., Liu, S., Browell, E., Gregory, G., Anderson, B., Sachse, G., Barrick, J., Blake, D., Talbot, R., and Pueschel, R.: Implications of Large Scale Shifts in Tropospheric NOx Levels in the Remote Tropical Pacific, J. Geophys. Res.-Atmos., 102, 28447–28468, https://doi.org/10.1029/97JD00011, 1997. a
Crutzen, P. J., Grooss, J. U., Bruhl, C., Muller, R., and Russell, J. M.: A Reevaluation of the Ozone Budget with HALOE UARS Data: No Evidence for the Ozone Deficit, Science, 268, 705–708, https://doi.org/10.1126/science.268.5211.705, 1995. a
Deshler, T., Stübi, R., Schmidlin, F. J., Mercer, J. L., Smit, H. G. J., Johnson, B. J., Kivi, R., and Nardi, B.: Methods to homogenize electrochemical concentration cell (ECC) ozonesonde measurements across changes in sensing solution concentration or ozonesonde manufacturer, Atmos. Meas. Tech., 10, 2021–2043, https://doi.org/10.5194/amt-10-2021-2017, 2017. a
Diallo, M., Riese, M., Birner, T., Konopka, P., Müller, R., Hegglin, M. I., Santee, M. L., Baldwin, M., Legras, B., and Ploeger, F.: Response of stratospheric water vapor and ozone to the unusual timing of El Niño and the QBO disruption in 2015–2016, Atmos. Chem. Phys., 18, 13055–13073, https://doi.org/10.5194/acp-18-13055-2018, 2018. a, b, c, d
Di Liberto, T.: Drought in the Pacific, National Oceanic Atmospheric Administation (NOAA), https://www.climate.gov/news-features/event-tracker/drought-pacific (last access: 8 January 2024), 2016. a
Dirksen, R. J., Sommer, M., Immler, F. J., Hurst, D. F., Kivi, R., and Vömel, H.: Reference quality upper-air measurements: GRUAN data processing for the Vaisala RS92 radiosonde, Atmos. Meas. Tech., 7, 4463–4490, https://doi.org/10.5194/amt-7-4463-2014, 2014. a
Dirksen, R. J., Bodeker, G. E., Thorne, P. W., Merlone, A., Reale, T., Wang, J., Hurst, D. F., Demoz, B. B., Gardiner, T. D., Ingleby, B., Sommer, M., von Rohden, C., and Leblanc, T.: Managing the transition from Vaisala RS92 to RS41 radiosondes within the Global Climate Observing System Reference Upper-Air Network (GRUAN): a progress report, Geosci. Instrum. Method. Data Syst., 9, 337–355, https://doi.org/10.5194/gi-9-337-2020, 2020. a
Folkins, I.: Tropical Ozone as an Indicator of Deep Convection, J. Geophys. Res., 107, 4184, https://doi.org/10.1029/2001JD001178, 2002. a, b
Froidevaux, L., Jiang, Y. B., Lambert, A., Livesey, N. J., Read, W. G., Waters, J. W., Browell, E. V., Hair, J. W., Avery, M. A., McGee, T. J., Twigg, L. W., Sumnicht, G. K., Jucks, K. W., Margitan, J. J., Sen, B., Stachnik, R. A., Toon, G. C., Bernath, P. F., Boone, C. D., Walker, K. A., Filipiak, M. J., Harwood, R. S., Fuller, R. A., Manney, G. L., Schwartz, M. J., Daffer, W. H., Drouin, B. J., Cofield, R. E., Cuddy, D. T., Jarnot, R. F., Knosp, B. W., Perun, V. S., Snyder, W. V., Stek, P. C., Thurstans, R. P., and Wagner, P. A.: Validation of Aura Microwave Limb Sounder Stratospheric Ozone Measurements, J. Geophys. Res., 113, D15S20, https://doi.org/10.1029/2007JD008771, 2008. a
Fueglistaler, S.: Stepwise Changes in Stratospheric Water Vapor?, J. Geophys. Res.-Atmos., 117, D13302, https://doi.org/10.1029/2012JD017582, 2012. a
Fueglistaler, S., Wernli, H., and Peter, T.: Tropical Troposphere-to-Stratosphere Transport Inferred from Trajectory Calculations, J. Geophys. Res.-Atmos., 109, https://doi.org/10.1029/2003JD004069, 2004. a
Fueglistaler, S., Dessler, A. E., Dunkerton, T. J., Folkins, I., Fu, Q., and Mote, P. W.: Tropical Tropopause Layer, Rev. Geophys., 47, RG1004, https://doi.org/10.1029/2008RG000267, 2009. a, b
Fujiwara, M., Tomikawa, Y., Kita, K., Kondo, Y., Komala, N., Saraspriya, S., Manik, T., Suripto, A., Kawakami, S., Ogawa, T., Kelana, E., Suhardi, B., Harijono, S., Kudsy, M., Sribimawati, T., and Yamanaka, M.: Ozonesonde Observations in the Indonesian Maritime Continent: A Case Study on Ozone Rich Layer in the Equatorial Upper Troposphere, Atmos. Environ., 37, 353–362, https://doi.org/10.1016/S1352-2310(02)00891-9, 2003. a
Gao, R. S., Rosenlof, K. H., Fahey, D. W., Wennberg, P. O., Hintsa, E. J., and Hanisco, T. F.: OH in the Tropical Upper Troposphere and Its Relationships to Solar Radiation and Reactive Nitrogen, J. Atmos. Chem., 71, 55–64, https://doi.org/10.1007/s10874-014-9280-2, 2014. a
Garfinkel, C. I. and Hartmann, D. L.: Effects of the El Niño–Southern Oscillation and the Quasi-Biennial Oscillation on Polar Temperatures in the Stratosphere, J. Geophys. Res., 112, D19112, https://doi.org/10.1029/2007JD008481, 2007. a
Gettelman, A. and Forster, P. d. F.: A Climatology of the Tropical Tropopause Layer, J. Meteorol. Soc. Jpn., 80, 911–924, https://doi.org/10.2151/jmsj.80.911, 2002. a, b, c
Graedel, T., Crutzen, P. J., Kläger, F., and Brühl, C.: Chemie der Atmosphäre: Bedeutung für Klima und Umwelt, Spektrum-Lehrbuch, Spektrum Akademischer Verlag, Heidelberg, ISBN 978-3-86025-204-8, 1994. a
Hannigan, J. W., Ortega, I., Shams, S. B., Blumenstock, T., Campbell, J. E., Conway, S., Flood, V., Garcia, O., Griffith, D., Grutter, M., Hase, F., Jeseck, P., Jones, N., Mahieu, E., Makarova, M., De Mazière, M., Morino, I., Murata, I., Nagahama, T., Nakijima, H., Notholt, J., Palm, M., Poberovskii, A., Rettinger, M., Robinson, J., Röhling, A. N., Schneider, M., Servais, C., Smale, D., Stremme, W., Strong, K., Sussmann, R., Te, Y., Vigouroux, C., and Wizenberg, T.: Global Atmospheric OCS Trend Analysis From 22 NDACC Stations, J. Geophys. Res.-Atmos., 127, e2021JD035764, https://doi.org/10.1029/2021JD035764, 2022. a
Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A., Muñoz-Sabater, J., Nicolas, J., Peubey, C., Radu, R., Schepers, D., Simmons, A., Soci, C., Abdalla, S., Abellan, X., Balsamo, G., Bechtold, P., Biavati, G., Bidlot, J., Bonavita, M., De Chiara, G., Dahlgren, P., Dee, D., Diamantakis, M., Dragani, R., Flemming, J., Forbes, R., Fuentes, M., Geer, A., Haimberger, L., Healy, S., Hogan, R. J., Hólm, E, Janisková, M., Keeley, S., Laloyaux, P., Lopez, P., Lupu, C., Radnoti, G., de Rosnay, P., Rozum, I., Vamborg, F., Villaume, S., and Thépaut, J.-N.: The ERA5 global reanalysis. Q. J. Roy. Meteor. Soc., 146, 1999–2049, https://doi.org/10.1002/qj.3803, 2020. a
Holton, J. R., Haynes, P. H., McIntyre, M. E., Douglass, A. R., Rood, R. B., and Pfister, L.: Stratosphere-Troposphere Exchange, Rev. Geophys., 33, 403–439, 1995. a
Huang, B., L'Heureux, M., Hu, Z.-Z., and Zhang, H.-M.: Ranking the Strongest ENSO Events While Incorporating SST Uncertainty, Geophys. Res. Lett., 43, 9165–9172, 2016. a
Hubert, D., Lambert, J.-C., Verhoelst, T., Granville, J., Keppens, A., Baray, J.-L., Bourassa, A. E., Cortesi, U., Degenstein, D. A., Froidevaux, L., Godin-Beekmann, S., Hoppel, K. W., Johnson, B. J., Kyrölä, E., Leblanc, T., Lichtenberg, G., Marchand, M., McElroy, C. T., Murtagh, D., Nakane, H., Portafaix, T., Querel, R., Russell III, J. M., Salvador, J., Smit, H. G. J., Stebel, K., Steinbrecht, W., Strawbridge, K. B., Stübi, R., Swart, D. P. J., Taha, G., Tarasick, D. W., Thompson, A. M., Urban, J., van Gijsel, J. A. E., Van Malderen, R., von der Gathen, P., Walker, K. A., Wolfram, E., and Zawodny, J. M.: Ground-based assessment of the bias and long-term stability of 14 limb and occultation ozone profile data records, Atmos. Meas. Tech., 9, 2497–2534, https://doi.org/10.5194/amt-9-2497-2016, 2016. a
Immler, F., Beninga, I., Ruhe, W., Stein, B., Mielke, B., Rutz, S., Terli, O., and Schrems, O.: A New LIDAR System for the Detection of Cloud and Aerosol Backscatter, Depolarization, Extinction, and Fluorescence, in: 23rd International Laser Radar Converence, 24–28 July 2006, Nara, Japan, edited by: Nagasawa, C. and Sugimoto, N., Laser Radar Society of Japan, Tsukuba, Japan, 35–38, https://doi.org/10013/epic.25672.d001, 2006. a
Kiladis, G. N., Straub, K. H., Reid, G. C., and Gage, K. S.: Aspects of Interannual and Intraseasonal Variability of the Tropopause and Lower Stratosphere, Q. J. Roy. Meteor. Soc., 127, 1961–1983, https://doi.org/10.1002/qj.49712757606, 2001. a
Klett, J. D.: Lidar Inversion with Variable Backscatter
Kley, D., Crutzen, P. J., Smit, H. G. J., Vomel, H., Oltmans, S. J., Grassl, H., and Ramanathan, V.: Observations of Near-Zero Ozone Concentrations Over the Convective Pacific: Effects on Air Chemistry, Science, 274, 230–233, https://doi.org/10.1126/science.274.5285.230, 1996. a
Komhyr, W. D.: Electrical Concentration Cells for Gas Analysis, Ann. Geophys.-Germany, 25, 203–210, 1969. a
Komhyr, W. D.: Operations Handbook – Ozone Measurements to 40-Km Altitude with Model 4A Electrochemical Concentration Cell (ECC) Ozonesondes (Used with 1680-MHz Radiosondes), Technical Memorandum ERL ARL-149, National Oceanic and Atmospheric Administration (NOAA), Silver Spring, MD, United States, 1986. a
Konopka, P., Ploeger, F., Tao, M., and Riese, M.: Zonally Resolved Impact of ENSO on the Stratospheric Circulation and Water Vapor Entry Values, J. Geophys. Res.-Atmos., 121, 11,486–11,501, https://doi.org/10.1002/2015JD024698, 2016. a
Krüger, K., Tegtmeier, S., and Rex, M.: Long-term climatology of air mass transport through the Tropical Tropopause Layer (TTL) during NH winter, Atmos. Chem. Phys., 8, 813–823, https://doi.org/10.5194/acp-8-813-2008, 2008. a
Manney, G. L., Froidevaux, L., Waters, J. W., Zurek, R. W., Read, W. G., Elson, L. S., Kumer, J. B., Mergenthaler, J. L., Roche, A. E., O'Neill, A., Harwood, R. S., Mackenzie, I., and Swinbank, R.: Chemical Depletion of Ozone in the Arctic Lower Stratosphere during Winter 1992–93, Nature, 370, 429–434, https://doi.org/10.1038/370429a0, 1994. a
Mapes, B. E.: Water's Two Height Scales: The Moist Adiabat and the Radiative Troposphere, Q. J. Roy. Meteor. Soc., 127, 2353–2366, https://doi.org/10.1002/qj.49712757708, 2001. a
Miles, W., Grecni, Z., Matsutaro, E. X., Colin, P., Keener, V., and Golbuu, Y.: Climate Change in Palau: Indicators and Considerations for Key Sectors, Tech. rep., East-West Center, 66 pp., https://doi.org/10.5281/zenodo.4124259, 2020. a
Müller, K., Graeser, J., Patris, S., Beninga, I., Ruhe, W., Ucharm, G., and Tradowsky, J.: Ozone sonde and radio sonde data record Palau Atmospheric Observatory 2016–2021 (V1.0), Zenodo [data set], https://doi.org/10.5281/zenodo.6920648, 2022. a, b
Müller, K., Wohltmann, I., von der Gathen, P., and Rex, M.: Air Mass Transport to the Tropical West Pacific Troposphere inferred from Ozone and Relative Humidity Balloon Observations above Palau, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2023-1518, 2023. a, b, c, d, e, f, g, h, i, j, k
NASA/GSFC: Southern Hemisphere Additional Ozonesondes version 6 ozonesonde profile data, National Aeronautics and Space Administration Goddard Space Flight Center (NASA/GSFC) [data set], https://doi.org/10.57721/SHADOZ-V06, 2019. a
Newell, R. E. and Gould-Stewart, S.: A Stratospheric Fountain?, J. Atmos. Sci., 38, 2789–2796, 1981. a
Newton, R., Vaughan, G., Ricketts, H. M. A., Pan, L. L., Weinheimer, A. J., and Chemel, C.: Ozonesonde profiles from the West Pacific Warm Pool: measurements and validation, Atmos. Chem. Phys., 16, 619–634, https://doi.org/10.5194/acp-16-619-2016, 2016. a, b
Notholt, J., Toon, G. C., Rinsland, C. P., Pougatchev, N. S., Jones, N. B., Connor, B. J., Weller, R., Gautrois, M., and Schrems, O.: Latitudinal Variations of Trace Gas Concentrations in the Free Troposphere Measured by Solar Absorption Spectroscopy during a Ship Cruise, J. Geophys. Res.-Atmos., 105, 1337–1349, https://doi.org/10.1029/1999JD900940, 2000. a
Ogino, S.-Y., Fujiwara, M., Shiotani, M., Hasebe, F., Matsumoto, J., T. Hoang, T. H., and T. Nguyen, T. T.: Ozone Variations over the Northern Subtropical Region Revealed by Ozonesonde Observations in Hanoi, J. Geophys. Res.-Atmos., 118, 3245–3257, https://doi.org/10.1002/jgrd.50348, 2013. a
Oltmans, S. J., Johnson, B. J., Harris, J. M., Thompson, A. M., Liu, H. Y., Chan, C. Y., Vömel, H., Fujimoto, T., Brackett, V. G., Chang, W. L., Chen, J.-P., Kim, J. H., Chan, L. Y., and Chang, H.-W.: Tropospheric Ozone over the North Pacific from Ozonesonde Observations, J. Geophys. Res., 109, D15S01, https://doi.org/10.1029/2003JD003466, 2004. a
Pan, L. L., Paulik, L. C., Honomichl, S. B., Munchak, L. A., Bian, J., Selkirk, H. B., and Vömel, H.: Identification of the Tropical Tropopause Transition Layer Using the Ozone-Water Vapor Relationship, J. Geophys. Res.-Atmos., 119, 3586–3599, https://doi.org/10.1002/2013JD020558, 2014. a, b
Pan, L. L., Honomichl, S. B., Randel, W. J., Apel, E. C., Atlas, E. L., Beaton, S. P., Bresch, J. F., Hornbrook, R., Kinnison, D. E., Lamarque, J.-F., Saiz-Lopez, A., Salawitch, R. J., and Weinheimer, A. J.: Bimodal Distribution of Free Tropospheric Ozone over the Tropical Western Pacific Revealed by Airborne Observations, Geophys. Res. Lett., 42, 7844–7851, https://doi.org/10.1002/2015GL065562, 2015. a, b, c, d, e, f, g, h, i
Pan, L. L., Atlas, E. L., Salawitch, R. J., Honomichl, S. B., Bresch, J. F., Randel, W. J., Apel, E. C., Hornbrook, R. S., Weinheimer, A. J., Anderson, D. C., Andrews, S. J., Baidar, S., Beaton, S. P., Campos, T. L., Carpenter, L. J., Chen, D., Dix, B., Donets, V., Hall, S. R., Hanisco, T. F., Homeyer, C. R., Huey, L. G., Jensen, J. B., Kaser, L., Kinnison, D. E., Koenig, T. K., Lamarque, J.-F., Liu, C., Luo, J., Luo, Z. J., Montzka, D. D., Nicely, J. M., Pierce, R. B., Riemer, D. D., Robinson, T., Romashkin, P., Saiz-Lopez, A., Schauffler, S., Shieh, O., Stell, M. H., Ullmann, K., Vaughan, G., Volkamer, R., and Wolfe, G.: The Convective Transport of Active Species in the Tropics (CONTRAST) Experiment, B. Am. Meteorol. Soc., 98, 106–128, https://doi.org/10.1175/BAMS-D-14-00272.1, 2017. a, b
Paulik, L. C. and Birner, T.: Quantifying the deep convective temperature signal within the tropical tropopause layer (TTL), Atmos. Chem. Phys., 12, 12183–12195, https://doi.org/10.5194/acp-12-12183-2012, 2012. a
Polhemus, D. A.: Drought in the U.S.-Affiliated Pacific Islands: A Multi-level Assessment, report, Pacific Islands Climate Science Center Honolulu, HI, https://doi.org/10.21429/C9ZS74, 2017. a
Prather, M. J., Zhu, X., Tang, Q., Hsu, J., and Neu, J. L.: An Atmospheric Chemist in Search of the Tropopause, J. Geophys. Res., 116, D04306, https://doi.org/10.1029/2010JD014939, 2011. a, b
Randel, W. J. and Jensen, E. J.: Physical Processes in the Tropical Tropopause Layer and Their Roles in a Changing Climate, Nat. Geosci., 6, 169–176, https://doi.org/10.1038/ngeo1733, 2013. a, b
Randel, W. J. and Thompson, A. M.: Interannual Variability and Trends in Tropical Ozone Derived from SAGE II Satellite Data and SHADOZ Ozonesondes, J. Geophys. Res., 116, D07303, https://doi.org/10.1029/2010JD015195, 2011. a
Randel, W. J., Park, M., Wu, F., and Livesey, N.: A Large Annual Cycle in Ozone above the Tropical Tropopause Linked to the Brewer–Dobson Circulation, J. Atmos. Sci., 64, 4479–4488, https://doi.org/10.1175/2007JAS2409.1, 2007. a, b
Randel, W. J., Garcia, R. R., Calvo, N., and Marsh, D.: ENSO Influence on Zonal Mean Temperature and Ozone in the Tropical Lower Stratosphere, Geophys. Res. Lett., 36, L15822, https://doi.org/10.1029/2009GL039343, 2009. a
Rex, M., Wohltmann, I., Ridder, T., Lehmann, R., Rosenlof, K., Wennberg, P., Weisenstein, D., Notholt, J., Krüger, K., Mohr, V., and Tegtmeier, S.: A tropical West Pacific OH minimum and implications for stratospheric composition, Atmos. Chem. Phys., 14, 4827–4841, https://doi.org/10.5194/acp-14-4827-2014, 2014. a, b, c, d, e, f, g, h, i
Riese, M., Ploeger, F., Rap, A., Vogel, B., Konopka, P., Dameris, M., and Forster, P.: Impact of Uncertainties in Atmospheric Mixing on Simulated UTLS Composition and Related Radiative Effects: Impact of Mixing on Radiative Effects, J. Geophys. Res.-Atmos., 117, D16305, https://doi.org/10.1029/2012JD017751, 2012. a
Rosen, J. M. and Kjome, N. T.: Backscattersonde: A New Instrument for Atmospheric Aerosol Research, Appl. Optics, 30, 1552–1561, 1991. a
Schneider, T., Bischoff, T., and Haug, G. H.: Migrations and Dynamics of the Intertropical Convergence Zone, Nature, 513, 45–53, https://doi.org/10.1038/nature13636, 2014. a
Schoeberl, M. R. and Dessler, A. E.: Dehydration of the stratosphere, Atmos. Chem. Phys., 11, 8433–8446, https://doi.org/10.5194/acp-11-8433-2011, 2011. a
Shiotani, M.: Annual, Quasi-Biennial, and El Niño-Southern Oscillation (ENSO) Time-Scale Variations in Equatorial Total Ozone, J. Geophys. Res., 97, 7625, https://doi.org/10.1029/92JD00530, 1992. a
Shonk, J. K. P., Guilyardi, E., Toniazzo, T., Woolnough, S. J., and Stockdale, T.: Identifying Causes of Western Pacific ITCZ Drift in ECMWF System 4 Hindcasts, Clim. Dynam., 50, 939–954, https://doi.org/10.1007/s00382-017-3650-9, 2018. a, b, c
Smit, H. G. J. and O3S-DQA Panel: Guidelines for Homogenization of Ozonesonde Data, SI2N/O3S-DQA Activity as part of “Past Changes in the Vertical Distribution of Ozone Assessment”, World Calibration Center for Ozone Sondes (WCCOS) of the World Meteorological Organization (WMO), https://www.wccos-josie.org/en/o3s-dqa/ (last access: 8 January 2024), 2012. a, b
Smit, H. G. J., Sträter, W., Johnson, B. J., Oltmans, S. J., Davies, J., Tarasick, D. W., Hoegger, B., Stubi, R., Schmidlin, F. J., Northam, T., Thompson, A. M., Witte, J. C., Boyd, I., and Posny, F.: Assessment of the Performance of ECC-ozonesondes under Quasi-Flight Conditions in the Environmental Simulation Chamber: Insights from the Juelich Ozone Sonde Intercomparison Experiment (JOSIE), J. Geophys. Res., 112, D19306, https://doi.org/10.1029/2006JD007308, 2007. a
Smit, H. G. J., Thompson, A. M., and the ASOPOS 2.0 Panel: Ozonesonde Measurement Principles and Best Operational Practices, WMO Global Atmosphere Watch Report Series, No. 268, World Meteorological Organization, Geneva, https://library.wmo.int/idurl/4/57720 (last access: 8 January 2024), 2021. a, b, c, d
Smit, H. G. J., Poyraz, D., Van Malderen, R., Thompson, A. M., Tarasick, D. W., Stauffer, R. M., Johnson, B. J., and Kollonige, D. E.: New insights from the Jülich Ozone Sonde Intercomparison Experiment: calibration functions traceable to one ozone reference instrument, Atmos. Meas. Tech., 17, 73–112, https://doi.org/10.5194/amt-17-73-2024, 2024. a
Smith, I. N., Moise, A. F., and Colman, R. A.: Large-Scale Circulation Features in the Tropical Western Pacific and Their Representation in Climate Models, J. Geophys. Res.-Atmos., 117, D04109, https://doi.org/10.1029/2011JD016667, 2012. a
Solomon, S., Garcia, R. R., Rowland, F. S., and Wuebbles, D. J.: On the Depletion of Antarctic Ozone, Nature, 321, 755–758, https://doi.org/10.1038/321755a0, 1986. a
Solomon, S., Thompson, D. W. J., Portmann, R. W., Oltmans, S. J., and Thompson, A. M.: On the Distribution and Variability of Ozone in the Tropical Upper Troposphere: Implications for Tropical Deep Convection and Chemical-Dynamical Coupling, Geophys. Res. Lett., 32, L23813, https://doi.org/10.1029/2005GL024323, 2005. a
Solomon, S., Rosenlof, K. H., Portmann, R. W., Daniel, J. S., Davis, S. M., Sanford, T. J., and Plattner, G.-K.: Contributions of Stratospheric Water Vapor to Decadal Changes in the Rate of Global Warming, Science, 327, 1219–1223, https://doi.org/10.1126/science.1182488, 2010. a
Sun, B., Reale, T., Schroeder, S., Pettey, M., and Smith, R.: On the Accuracy of Vaisala RS41 versus RS92 Upper-Air Temperature Observations, J. Atmos. Ocean. Tech., 36, 635–653, https://doi.org/10.1175/JTECH-D-18-0081.1, 2019. a
Sun, X., Palm, M., Müller, K., Hachmeister, J., and Notholt, J.: Determination of the chemical equator from GEOS-Chem model simulation: a focus on the tropical western Pacific region, Atmos. Chem. Phys., 23, 7075–7090, https://doi.org/10.5194/acp-23-7075-2023, 2023. a
Taguchi, M.: Observed Connection of the Stratospheric Quasi-Biennial Oscillation with El Niño–Southern Oscillation in Radiosonde Data, J. Geophys. Res., 115, D18120, https://doi.org/10.1029/2010JD014325, 2010. a
Tarasick, D. W., Smit, H. G. J., Thompson, A. M., Morris, G. A., Witte, J. C., Davies, J., Nakano, T., Van Malderen, R., Stauffer, R. M., Johnson, B. J., Stübi, R., Oltmans, S. J., and Vömel, H.: Improving ECC Ozonesonde Data Quality: Assessment of Current Methods and Outstanding Issues, Earth Space Sci., 8, e2019EA000914, https://doi.org/10.1029/2019EA000914, 2021. a
Thompson, A. M., Witte, J. C., McPeters, R. D., Oltmans, S. J., Schmidlin, F. J., Logan, J. A., Fujiwara, M., Kirchhoff, V. W. J. H., Posny, F., Coetzee, G. J. R., Hoegger, B., Kawakami, S., Toshihiro, O., Johnson, B. J., Vömel, H., and Labow, G. J.: Southern Hemisphere Additional Ozonesondes (SHADOZ) 1998–2000 Tropical Ozone Climatology 1. Comparison with Total Ozone Mapping Spectrometer (TOMS) and Ground-Based Measurements, J. Geophys. Res., 108, 8238, https://doi.org/10.1029/2001JD000967, 2003a. a, b, c
Thompson, A. M., Witte, J. C., Oltmans, S. J., Schmidlin, F. J., Logan, J. A., Fujiwara, M., Kirchhoff, V. W. J. H., Posny, F., Coetzee, G. J. R., Hoegger, B., Kawakami, S., Ogawa, T., Fortuin, J. P. F., and Kelder, H. M.: Southern Hemisphere Additional Ozonesondes (SHADOZ) 1998–2000 Tropical Ozone Climatology 2. Tropospheric Variability and the Zonal Wave-One, J. Geophys. Res., 108, 8241, https://doi.org/10.1029/2002JD002241, 2003b. a, b, c, d
Thompson, A. M., Witte, J. C., Smit, H. G. J., Oltmans, S. J., Johnson, B. J., Kirchhoff, V. W. J. H., and Schmidlin, F. J.: Southern Hemisphere Additional Ozonesondes (SHADOZ) 1998–2004 Tropical Ozone Climatology: 3. Instrumentation, Station-to-Station Variability, and Evaluation with Simulated Flight Profiles, J. Geophys. Res., 112, D03304, https://doi.org/10.1029/2005JD007042, 2007. a, b
Thompson, A. M., Allen, A. L., Lee, S., Miller, S. K., and Witte, J. C.: Gravity and Rossby Wave Signatures in the Tropical Troposphere and Lower Stratosphere Based on Southern Hemisphere Additional Ozonesondes (SHADOZ), 1998–2007, J. Geophys. Res., 116, D05302, https://doi.org/10.1029/2009JD013429, 2011. a, b
Thompson, A. M., Miller, S. K., Tilmes, S., Kollonige, D. W., Witte, J. C., Oltmans, S. J., Johnson, B. J., Fujiwara, M., Schmidlin, F. J., Coetzee, G. J. R., Komala, N., Maata, M., bt Mohamad, M., Nguyo, J., Mutai, C., Ogino, S.-Y., Da Silva, F. R., Leme, N. M. P., Posny, F., Scheele, R., Selkirk, H. B., Shiotani, M., Stübi, R., Levrat, G., Calpini, B., Thouret, V., Tsuruta, H., Canossa, J. V., Vömel, H., Yonemura, S., Diaz, J. A., Tan Thanh, N. T., and Thuy Ha, H. T.: Southern Hemisphere Additional Ozonesondes (SHADOZ) Ozone Climatology (2005–2009): Tropospheric and Tropical Tropopause Layer (TTL) Profiles with Comparisons to OMI-based Ozone Products, J. Geophys. Res.-Atmos., 117, D23301, https://doi.org/10.1029/2011JD016911, 2012. a, b, c, d, e
Thompson, A. M., Witte, J. C., Sterling, C., Jordan, A., Johnson, B. J., Oltmans, S. J., Fujiwara, M., Vömel, H., Allaart, M., Piters, A., Coetzee, G. J. R., Posny, F., Corrales, E., Diaz, J. A., Félix, C., Komala, N., Lai, N., Ahn Nguyen, H. T., Maata, M., Mani, F., Zainal, Z., Ogino, S.-y., Paredes, F., Penha, T. L. B., Silva, F. R., Sallons-Mitro, S., Selkirk, H. B., Schmidlin, F. J., Stübi, R., and Thiongo, K.: First Reprocessing of Southern Hemisphere Additional Ozonesondes (SHADOZ) Ozone Profiles (1998–2016): 2. Comparisons With Satellites and Ground-Based Instruments, J. Geophys. Res.-Atmos., 122, 13000–13025, https://doi.org/10.1002/2017JD027406, 2017. a, b, c
Thompson, A. M., Smit, H. G. J., Witte, J. C., Stauffer, R. M., Johnson, B. J., Morris, G., von der Gathen, P., Van Malderen, R., Davies, J., Piters, A., Allaart, M., Posny, F., Kivi, R., Cullis, P., Hoang Anh, N. T., Corrales, E., Machinini, T., da Silva, F. R., Paiman, G., Thiong'o, K., Zainal, Z., Brothers, G. B., Wolff, K. R., Nakano, T., Stübi, R., Romanens, G., Coetzee, G. J. R., Diaz, J. A., Mitro, S., Mohamad, M., and Ogino, S.-Y.: Ozonesonde Quality Assurance: The JOSIE–SHADOZ (2017) Experience, B. Am. Meteorol. Soc., 100, 155–171, https://doi.org/10.1175/BAMS-D-17-0311.1, 2019. a, b, c, d, e
Thompson, A. M., Stauffer, R. M., Wargan, K., Witte, J. C., Kollonige, D. E., and Ziemke, J. R.: Regional and Seasonal Trends in Tropical Ozone From SHADOZ Profiles: Reference for Models and Satellite Products, J. Geophys. Res.-Atmos., 126, e2021JD034691, https://doi.org/10.1029/2021JD034691, 2021. a
Vaisala: Vaisala Radiosonde RS41 Measurement Performance, White paper, document identifier: B211356EN-B, 2017. a
Vigouroux, C., De Mazière, M., Demoulin, P., Servais, C., Hase, F., Blumenstock, T., Kramer, I., Schneider, M., Mellqvist, J., Strandberg, A., Velazco, V., Notholt, J., Sussmann, R., Stremme, W., Rockmann, A., Gardiner, T., Coleman, M., and Woods, P.: Evaluation of tropospheric and stratospheric ozone trends over Western Europe from ground-based FTIR network observations, Atmos. Chem. Phys., 8, 6865–6886, https://doi.org/10.5194/acp-8-6865-2008, 2008. a
Vömel, H. and Diaz, K.: Ozone sonde cell current measurements and implications for observations of near-zero ozone concentrations in the tropical upper troposphere, Atmos. Meas. Tech., 3, 495–505, https://doi.org/10.5194/amt-3-495-2010, 2010. a, b
Vömel, H., David, D, E., and Smith, K.: Accuracy of Tropospheric and Stratospheric Water Vapor Measurements by the Cryogenic Frost Point Hygrometer: Instrumental Details and Observations, J. Geophys. Res.-Atmos., 112, D08305, https://doi.org/10.1029/2006JD007224, 2007. a
Vömel, H., Naebert, T., Dirksen, R., and Sommer, M.: An update on the uncertainties of water vapor measurements using cryogenic frost point hygrometers, Atmos. Meas. Tech., 9, 3755–3768, https://doi.org/10.5194/amt-9-3755-2016, 2016. a
Vömel, H., Smit, H. G. J., Tarasick, D., Johnson, B., Oltmans, S. J., Selkirk, H., Thompson, A. M., Stauffer, R. M., Witte, J. C., Davies, J., van Malderen, R., Morris, G. A., Nakano, T., and Stübi, R.: A new method to correct the electrochemical concentration cell (ECC) ozonesonde time response and its implications for “background current” and pump efficiency, Atmos. Meas. Tech., 13, 5667–5680, https://doi.org/10.5194/amt-13-5667-2020, 2020. a, b
Witte, J. C., Thompson, A. M., Smit, H. G. J., Fujiwara, M., Posny, F., Coetzee, G. J. R., Northam, E. T., Johnson, B. J., Sterling, C. W., Mohamad, M., Ogino, S.-Y., Jordan, A., and da Silva, F. R.: First Reprocessing of Southern Hemisphere ADditional OZonesondes (SHADOZ) Profile Records (1998–2015): 1. Methodology and Evaluation: SHADOZ Reprocessed Ozonesonde Profiles, J. Geophys. Res.-Atmos., 122, 6611–6636, https://doi.org/10.1002/2016JD026403, 2017. a, b
Witte, J. C., Thompson, A. M., Smit, H. G. J., Vömel, H., Posny, F., and Stübi, R.: First Reprocessing of Southern Hemisphere ADditional OZonesondes Profile Records: 3. Uncertainty in Ozone Profile and Total Column, J. Geophys. Res.-Atmos., 123, 3243–3268, https://doi.org/10.1002/2017JD027791, 2018. a, b
Wolter, K. and Timlin, M. S.: El Niño Southern Oscillation Behaviour since 1871 as Diagnosed in an Extended Multivariate ENSO Index (MEI.Ext), Int. J. Climatol., 31, 1074–1087, https://doi.org/10.1002/joc.2336, 2011. a, b
Short summary
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.
The Palau Atmospheric Observatory is introduced as an ideal site to detect changes in...
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