Articles | Volume 18, issue 9
https://doi.org/10.5194/essd-18-6859-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/essd-18-6859-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Data description article
| 
16 Sep 2026
Data description article |
| 16 Sep 2026
| 16 Sep 2026
Signal-domain guided deep learning for gap-filling of XCO and XCH4: a masked spatio-temporal fusion of TROPOMI and GEOS-Chem (2019–2023)
Chengkun An
Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
Yuan Tian
CORRESPONDING AUTHOR
Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
National Key Laboratory of Opto-Electronic Information Acquisition and Protection Technology, Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui, China
Zhiwei Li
Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
Qiaoyu Jiang
Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
Peize Lin
School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei 230026, China
Bowen Chang
Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
Jingkai Xue
School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei 230026, China
National Key Laboratory of Opto-Electronic Information Acquisition and Protection Technology, Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui, China
Key Laboratory of Environmental Optics and Technology, Anhui Institute of Optics and Fine Mechanics, HFIPS, Chinese Academy of Sciences, Hefei 230031, China
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This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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We used machine learning to separate meteorological and emission effects on PM2.5 over Northeast China. Pollution dropped nearly 40 %, mainly due to emission reductions. While weather often cleaned the air, it worsened all severe pollution episodes. Seasonal agricultural burning also caused sharp spikes. Our findings suggest that future efforts must shift from general cuts to episode-targeted actions, stricter burning controls, and weather-aware measures for further improvements.
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We used satellite and ground observations to study changes in nitrogen dioxide transport over the Tibetan Plateau during the past two decades. The results show that near-surface pollution has decreased, while atmospheric NO₂ column signals have increased. The Tibetan Plateau may play a certain role as a transit region in regional pollution transport, suggesting that its influence on surrounding air quality and environmental changes deserves more attention.
Zhongfeng Pan, Hao Yin, Zhenda Sun, Chongyang Li, Youwen Sun, and Cheng Liu
Atmos. Chem. Phys., 26, 2545–2559, https://doi.org/10.5194/acp-26-2545-2026, https://doi.org/10.5194/acp-26-2545-2026, 2026
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This study examines air pollution in Beijing-Tianjin-Hebei and the Yangtze River Delta from 2015 to 2022. PM2.5 (particulate matter) decreased by 9.1-31.4 μg/m³ and PM10 by 9.8–42.9 μg/m³. Weather factors like humidity, air pressure, and rainfall influenced pollution, with tailored solutions needed for different regions.
Zhenda Sun, Hao Yin, Zhongfeng Pan, Chongyang Li, Xiao Lu, Ke Liu, Youwen Sun, and Cheng Liu
Atmos. Chem. Phys., 25, 6823–6842, https://doi.org/10.5194/acp-25-6823-2025, https://doi.org/10.5194/acp-25-6823-2025, 2025
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This study investigates the variability and driving forces of transboundary CO transport flux over the Tibetan Plateau from May 2018 to April 2024. During this period, external CO influx increased by 2.86 Tg yr-1, while internal efflux slightly declined by 1.70 Tg yr-1. The rising influx in recent years is likely linked to the rapid increase in CO concentrations from South Asia.
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Atmos. Chem. Phys., 24, 10093–10112, https://doi.org/10.5194/acp-24-10093-2024, https://doi.org/10.5194/acp-24-10093-2024, 2024
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We identified the contributions of ozone (O3) and nitrous acid (HONO) to the production rates of hydroxide (OH) in vertical space on the Tibetan Plateau (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 in lower-altitudes areas. This study enriches the understanding of vertical distribution of atmospheric components and explains the strong atmospheric oxidation capacity (AOC) on the TP.
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.
Carlos Alberti, Frank Hase, Matthias Frey, Darko Dubravica, Thomas Blumenstock, Angelika Dehn, Paolo Castracane, Gregor Surawicz, Roland Harig, Bianca C. Baier, Caroline Bès, Jianrong Bi, Hartmut Boesch, André Butz, Zhaonan Cai, Jia Chen, Sean M. Crowell, Nicholas M. Deutscher, Dragos Ene, Jonathan E. Franklin, Omaira García, David Griffith, Bruno Grouiez, Michel Grutter, Abdelhamid Hamdouni, Sander Houweling, Neil Humpage, Nicole Jacobs, Sujong Jeong, Lilian Joly, Nicholas B. Jones, Denis Jouglet, Rigel Kivi, Ralph Kleinschek, Morgan Lopez, Diogo J. Medeiros, Isamu Morino, Nasrin Mostafavipak, Astrid Müller, Hirofumi Ohyama, Paul I. Palmer, Mahesh Pathakoti, David F. Pollard, Uwe Raffalski, Michel Ramonet, Robbie Ramsay, Mahesh Kumar Sha, Kei Shiomi, William Simpson, Wolfgang Stremme, Youwen Sun, Hiroshi Tanimoto, Yao Té, Gizaw Mengistu Tsidu, Voltaire A. Velazco, Felix Vogel, Masataka Watanabe, Chong Wei, Debra Wunch, Marcia Yamasoe, Lu Zhang, and Johannes Orphal
Atmos. Meas. Tech., 15, 2433–2463, https://doi.org/10.5194/amt-15-2433-2022, https://doi.org/10.5194/amt-15-2433-2022, 2022
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Space-borne greenhouse gas missions require ground-based validation networks capable of providing fiducial reference measurements. Here, considerable refinements of the calibration procedures for the COllaborative Carbon Column Observing Network (COCCON) are presented. Laboratory and solar side-by-side procedures for the characterization of the spectrometers have been refined and extended. Revised calibration factors for XCO2, XCO and XCH4 are provided, incorporating 47 new spectrometers.
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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We demonstrated the usage of the Fourier transform infrared (FTIR) spectroscopic technique to characterize in real time the hygroscopic growth properties of nanoparticles and their phase transition micro-dynamics at the molecular level. We first realize real-time measurements of water content and dry nanoparticle mass to characterize hygroscopic growth factors. We then identify in real time the hydration interactions and the dynamic hygroscopic growth process of the functional groups.
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Short summary
This study addresses the problem of missing carbon monoxide and methane data in satellite observations by integrating satellite observations, atmospheric chemistry simulations, and artificial intelligence techniques to generate complete daily datasets from 2019 to 2023 with a global resolution of 0.25° and a China-specific resolution of 0.05°. The dataset can support research on atmospheric changes, wildfire signals, agricultural regions, and related environmental impacts.
This study addresses the problem of missing carbon monoxide and methane data in satellite...
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