Articles | Volume 19, issue 21
https://doi.org/10.5194/amt-19-7231-2026
© 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/amt-19-7231-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
12 Nov 2026
Research article |
| 12 Nov 2026
| 12 Nov 2026
Two decades of kilometer-scale daily PM2.5 from satellite observations and machine learning reveal geographically diverging exposure in Ghana
Abhishek Anand
CORRESPONDING AUTHOR
Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, USA
Joe A. Amooli
Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, USA
Department of Earth and Environmental Sciences, Columbia University, New York, NY, USA
Selina Amoah
Ghana Environmental Protection Authority, Accra, Ghana
Esi Nerquaye Tetteh
Ghana Environmental Protection Authority, Accra, Ghana
Nana Ama Browne Klutse
Ghana Environmental Protection Authority, Accra, Ghana
Clement Mensah Ackaah
Ghana Environmental Protection Authority, Accra, Ghana
Benjamin Essien
Ghana Environmental Protection Authority, Accra, Ghana
Kingsley Mawuli Amegah
Ghana Environmental Protection Authority, Accra, Ghana
Daniel M. Westervelt
Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, USA
Department of Earth and Environmental Sciences, Columbia University, New York, NY, USA
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Gopalakrishna Sreerekha Gopikrishnan, Daniel M. Westervelt, and Jayanarayanan Kuttippurath
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Samuel Bartusek, Yutian Wu, Mingfang Ting, Arlene Fiore, and Daniel M. Westervelt
EGUsphere, https://doi.org/10.5194/egusphere-2025-4874, https://doi.org/10.5194/egusphere-2025-4874, 2025
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Joe Adabouk Amooli, Marianne T. Lund, Sourangsu Chowdhury, Gunnar Myhre, Ane N. Johansen, Bjørn H. Samset, and Daniel M. Westervelt
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Atmos. Chem. Phys., 25, 10523–10557, https://doi.org/10.5194/acp-25-10523-2025, https://doi.org/10.5194/acp-25-10523-2025, 2025
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Duncan Watson-Parris, Laura J. Wilcox, Camilla W. Stjern, Robert J. Allen, Geeta Persad, Massimo A. Bollasina, Annica M. L. Ekman, Carley E. Iles, Manoj Joshi, Marianne T. Lund, Daniel McCoy, Daniel M. Westervelt, Andrew I. L. Williams, and Bjørn H. Samset
Atmos. Chem. Phys., 25, 4443–4454, https://doi.org/10.5194/acp-25-4443-2025, https://doi.org/10.5194/acp-25-4443-2025, 2025
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Stephanie Fiedler, Vaishali Naik, Fiona M. O'Connor, Christopher J. Smith, Paul Griffiths, Ryan J. Kramer, Toshihiko Takemura, Robert J. Allen, Ulas Im, Matthew Kasoar, Angshuman Modak, Steven Turnock, Apostolos Voulgarakis, Duncan Watson-Parris, Daniel M. Westervelt, Laura J. Wilcox, Alcide Zhao, William J. Collins, Michael Schulz, Gunnar Myhre, and Piers M. Forster
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Climate scientists want to better understand modern climate change. Thus, climate model experiments are performed and compared. The results of climate model experiments differ, as assessed in the latest Intergovernmental Panel on Climate Change (IPCC) assessment report. This article gives insights into the challenges and outlines opportunities for further improving the understanding of climate change. It is based on views of a group of experts in atmospheric composition–climate interactions.
Laura J. Wilcox, Robert J. Allen, Bjørn H. Samset, Massimo A. Bollasina, Paul T. Griffiths, James Keeble, Marianne T. Lund, Risto Makkonen, Joonas Merikanto, Declan O'Donnell, David J. Paynter, Geeta G. Persad, Steven T. Rumbold, Toshihiko Takemura, Kostas Tsigaridis, Sabine Undorf, and Daniel M. Westervelt
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Forwood Wiser, Bryan K. Place, Siddhartha Sen, Havala O. T. Pye, Benjamin Yang, Daniel M. Westervelt, Daven K. Henze, Arlene M. Fiore, and V. Faye McNeill
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Short summary
Air pollution remains poorly characterized across sub-Saharan Africa due to sparse monitoring infrastructure. We developed a multi-model machine learning framework to generate a 21-year, high-resolution PM2.5 dataset for Ghana, revealing pronounced spatial and seasonal variability, persistent geographic exposure disparities, and contrasting long-term trends. These findings provide new evidence to support air-quality management, health assessments, and environmental policy in data-sparse regions.
Air pollution remains poorly characterized across sub-Saharan Africa due to sparse monitoring...
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