Articles | Volume 26, issue 11
https://doi.org/10.5194/acp-26-7765-2026
© 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-26-7765-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
02 Jun 2026
Research article |
| 02 Jun 2026
| 02 Jun 2026
Distinct dual-isotopic signatures of major methane sources in South Asia
Department of Environmental Science (ACES) and the Bolin Centre for Climate Research, Stockholm University, Stockholm 10691, Sweden
Katja Belec
Department of Environmental Science (ACES) and the Bolin Centre for Climate Research, Stockholm University, Stockholm 10691, Sweden
Henry Holmstrand
Department of Environmental Science (ACES) and the Bolin Centre for Climate Research, Stockholm University, Stockholm 10691, Sweden
Josh Balacky
Department of Environmental Science (ACES) and the Bolin Centre for Climate Research, Stockholm University, Stockholm 10691, Sweden
Abdus Salam
Department of Chemistry, University of Dhaka, Dhaka 1000, Bangladesh
Krishnakant Budhavant
Divecha Centre for Climate Change, Indian Institute of Science, Bangalore 560012, India
Maldives Climate Observatory-Hanimaadhoo (MCOH), Maldives Meteorological Services, H. Dh. Hanimaadhoo 02020, Maldives
Mohanan Remani Manoj
Department of Environmental Science (ACES) and the Bolin Centre for Climate Research, Stockholm University, Stockholm 10691, Sweden
Khaled Shaifullah Joy
Department of Chemistry, University of Dhaka, Dhaka 1000, Bangladesh
Department of Chemistry, Drexel University, Philadelphia, 19104, United States
Md. Alamin Hossain
Department of Chemistry, University of Dhaka, Dhaka 1000, Bangladesh
Atinderpal Singh
Department of Environmental Studies, University of Delhi, Delhi, 110007, India
Anil Patel
Geosciences Division, Physical Research Laboratory, Ahmedabad 380009, India
Bagchi School of Public Health, Ahmedabad University, Ahmedabad 380009, Gujarat, India
The Climate Institute, Ahmedabad University, Ahmedabad 380009, Gujarat, India
Neeraj Rastogi
Geosciences Division, Physical Research Laboratory, Ahmedabad 380009, India
Chinmay Mallik
Department of Atmospheric Science, Central University of Rajasthan, Ajmer 305801, India
Kirpa Ram
Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi 221005, India
Gyanesh Kumar Singh
Department of Civil Engineering, Indian Institute of Technology Kanpur, Kanpur, 208016, India
Air Quality and Aerosol Metrology (AQAM) Group, National Physical Laboratory (NPL), Teddington, London TW11 0LW, UK
Örjan Gustafsson
CORRESPONDING AUTHOR
Department of Environmental Science (ACES) and the Bolin Centre for Climate Research, Stockholm University, Stockholm 10691, Sweden
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Revised manuscript not accepted
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Nair K. Kala, Narayana Sarma Anand, Mohanan R. Manoj, Harshavardhana S. Pathak, Krishnaswamy K. Moorthy, and Sreedharan K. Satheesh
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Himadri Sekhar Bhowmik, Ashutosh Shukla, Vipul Lalchandani, Jay Dave, Neeraj Rastogi, Mayank Kumar, Vikram Singh, and Sachchida Nand Tripathi
Atmos. Meas. Tech., 15, 2667–2684, https://doi.org/10.5194/amt-15-2667-2022, https://doi.org/10.5194/amt-15-2667-2022, 2022
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Roland Vernooij, Ulrike Dusek, Maria Elena Popa, Peng Yao, Anupam Shaikat, Chenxi Qiu, Patrik Winiger, Carina van der Veen, Thomas Callum Eames, Natasha Ribeiro, and Guido R. van der Werf
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Landscape fires are a major source of greenhouse gases and aerosols, particularly in sub-tropical savannas. Stable carbon isotopes in emissions can be used to trace the contribution of C3 plants (e.g. trees or shrubs) and C4 plants (e.g. savanna grasses) to greenhouse gases and aerosols if the process is well understood. This helps us to link individual vegetation types to emissions, identify biomass burning emissions in the atmosphere, and improve the reconstruction of historic fire regimes.
Mohanan R. Manoj, Sreedharan K. Satheesh, Krishnaswamy K. Moorthy, Jamie Trembath, and Hugh Coe
Atmos. Chem. Phys., 21, 8979–8997, https://doi.org/10.5194/acp-21-8979-2021, https://doi.org/10.5194/acp-21-8979-2021, 2021
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Jannik Martens, Evgeny Romankevich, Igor Semiletov, Birgit Wild, Bart van Dongen, Jorien Vonk, Tommaso Tesi, Natalia Shakhova, Oleg V. Dudarev, Denis Kosmach, Alexander Vetrov, Leopold Lobkovsky, Nikolay Belyaev, Robie W. Macdonald, Anna J. Pieńkowski, Timothy I. Eglinton, Negar Haghipour, Salve Dahle, Michael L. Carroll, Emmelie K. L. Åström, Jacqueline M. Grebmeier, Lee W. Cooper, Göran Possnert, and Örjan Gustafsson
Earth Syst. Sci. Data, 13, 2561–2572, https://doi.org/10.5194/essd-13-2561-2021, https://doi.org/10.5194/essd-13-2561-2021, 2021
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The paper describes the establishment, structure and current status of the first Circum-Arctic Sediment CArbon DatabasE (CASCADE), which is a scientific effort to harmonize and curate all published and unpublished data of carbon, nitrogen, carbon isotopes, and terrigenous biomarkers in sediments of the Arctic Ocean in one database. CASCADE will enable a variety of studies of the Arctic carbon cycle and thus contribute to a better understanding of how climate change affects the Arctic.
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Short summary
Methane is a powerful greenhouse gas, but its sources remain uncertain in many regions. The isotope fingerprints of methane are diagnostic of its sources, yet their source end-members are poorly constrained for South Asia. Here we determined the methane isotope signal for major sources in South Asia and found these to differ from global averages. Improved regional-specific isotope source fingerprints will help to improve top-down assessments of methane budgets and climate mitigation strategies.
Methane is a powerful greenhouse gas, but its sources remain uncertain in many regions. The...
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