Articles | Volume 26, issue 12
https://doi.org/10.5194/acp-26-9257-2026
© 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/acp-26-9257-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Investigating information transfer in CO2 flux inversions: an analysis of ensemble Kalman filter based on Monte Carlo simulations
Shidong Fan
Department of Ocean Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
Center for the Oceanic and Atmospheric Science at SUSTech (COAST), Southern University of Science and Technology, Shenzhen 518055, China
Department of Ocean Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
Center for the Oceanic and Atmospheric Science at SUSTech (COAST), Southern University of Science and Technology, Shenzhen 518055, China
Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, China
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EGUsphere, https://doi.org/10.5194/egusphere-2025-6272, https://doi.org/10.5194/egusphere-2025-6272, 2025
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We developed a carbon assimilation system to construct a near-real-time 4-km anthropogenic inventory in the Pearl River Delta. We analyze spatiotemporal emission distributions, compare the inversion inventories against statistical emissions, and elucidate their relationship with ambient CO2 concentrations. The results of this study provide a robust scientific basis for advancing the dynamic updating and quantitative evaluation of anthropogenic emissions across meso- to microscale domains.
Naveed Ahmad, Changqing Lin, Alexis K. H. Lau, Jhoon Kim, Tianshu Zhang, Fangqun Yu, Chengcai Li, Ying Li, Jimmy C. H. Fung, and Xiang Qian Lao
Atmos. Chem. Phys., 24, 9645–9665, https://doi.org/10.5194/acp-24-9645-2024, https://doi.org/10.5194/acp-24-9645-2024, 2024
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This study developed a nested machine learning model to convert the GEMS NO2 column measurements into ground-level concentrations across China. The model directly incorporates the NO2 mixing height (NMH) into the methodological framework. The study underscores the importance of considering NMH when estimating ground-level NO2 from satellite column measurements and highlights the significant advantages of new-generation geostationary satellites in air quality monitoring.
Weilun Zhao, Ying Li, Gang Zhao, Song Guo, Nan Ma, Shuya Hu, and Chunsheng Zhao
Atmos. Chem. Phys., 23, 14889–14902, https://doi.org/10.5194/acp-23-14889-2023, https://doi.org/10.5194/acp-23-14889-2023, 2023
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Studies have concentrated on particles containing black carbon (BC) smaller than 700 nm because of technical limitations. In this study, BC-containing particles larger than 700 nm (BC>700) were measured, highlighting their importance to total BC mass and absorption. The contribution of BC>700 to the BC direct radiative effect was estimated, highlighting the necessity to consider the whole size range of BC-containing particles in the model estimation of BC radiative effects.
Weilun Zhao, Gang Zhao, Ying Li, Song Guo, Nan Ma, Lizi Tang, Zirui Zhang, and Chunsheng Zhao
Atmos. Meas. Tech., 15, 6807–6817, https://doi.org/10.5194/amt-15-6807-2022, https://doi.org/10.5194/amt-15-6807-2022, 2022
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A new method to determine black carbon mass size distribution (BCMSD) was proposed using the size-resolved absorption coefficient measured by an aerodynamic aerosol classifier in tandem with an aethalometer. This new method fills the gap in the high-time-resolution measurement of BCMSD ranging from upper submicron particle sizes to larger than 1 µm. This method can be applied to field measurement of BCMSD extensively for better understanding BC aging and better estimating the BC climate effect.
Shidong Fan and Ying Li
Atmos. Chem. Phys., 22, 7331–7351, https://doi.org/10.5194/acp-22-7331-2022, https://doi.org/10.5194/acp-22-7331-2022, 2022
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We investigated the mechanisms by which marine-emitted halogens influence the OH radical, which is not considered in air quality forecasting model systems. The atmospheric OH radical has a complicated response to halogen emissions by species through both physical and chemical processes. Over ocean, inorganic iodine is the controlling species and chemistry is more important. Over land, the physics of sea salt aerosols are more important. The mechanism is applicable to other circumstances.
Ying Li, Xiangjun Zhao, Xuejiao Deng, and Jinhui Gao
Atmos. Chem. Phys., 22, 3861–3873, https://doi.org/10.5194/acp-22-3861-2022, https://doi.org/10.5194/acp-22-3861-2022, 2022
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This study finds a new phenomenon of weak wind deepening (WWD) associated with the peripheral circulation of typhoon and gives the influence mechanism of WWD on its contribution to daily variation during sustained ozone episodes. The WWD provides the premise for pollution accumulation in the whole PBL and continued enhancement of ground-level ozone via vertical mixing processes. These findings could benefit the daily daytime ozone forecast in the PRD region and other areas.
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Short summary
Atmospheric CO2 inversions infer surface fluxes from concentration measurements, yet results vary widely across systems. Using ensemble simulations as well as variational theory, this study shows that the assumed spatial and temporal correlations of surface fluxes largely determine how observational information propagates. Transport shapes patterns, but prior correlations control scale and strength, explaining signal amplification, dilution, and flux misattribution.
Atmospheric CO2 inversions infer surface fluxes from concentration measurements, yet results...
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