Emissions of HFC-23 do not reflect commitments made under the Kigali Amendment
HFC-23 (trifluoromethane) is a potent greenhouse gas released to the atmosphere primarily as a by-product of HCFC-22 (chlorodifluoromethane) synthesis. Since 2020, the Kigali Amendment to the Montreal Protocol has required Parties to destroy their HFC-23 emissions to the extent possible. Here, we present updated HFC-23 emissions estimated from atmospheric observations. Globally, emissions fell to 14.0 ± 0.9 Gg yr<sup>-1</sup> in 2023 from their maximum in 2019 of 17.3 ± 0.8 Gg yr<sup>-1</sup>, but remained five times higher than reported in 2021. Atmospheric observation-based emissions for eastern China, the world's largest HCFC-22 producer, were also found to be substantially higher than 2020-2022 reported emissions. We estimate that potential HFC-23 sources not directly linked to HCFC-22 production explain only a minor, albeit highly uncertain, fraction of this discrepancy. Our findings suggest that HFC-23 emissions have not been destroyed to the extent reported by the Parties since the implementation of the Kigali Amendment.
Authors
- Jens Mühle (ORCID: https://orcid.org/0000-0001-9776-3642)
- Ronald G. Prinn (ORCID: https://orcid.org/0000-0001-5925-3801)
- Ray F. Weiss (ORCID: https://orcid.org/0000-0001-9551-7739)
- Luke M. Western (ORCID: https://orcid.org/0000-0002-0043-711X)
- Kieran Stanley (ORCID: https://orcid.org/0000-0003-3388-0932)
- Haklim Choi (ORCID: https://orcid.org/0000-0001-5117-1406)
- Dickon Young (ORCID: https://orcid.org/0000-0002-6723-3138)
- Christina M. Harth (ORCID: https://orcid.org/0000-0003-0544-1932)
- Paul J. Fraser (ORCID: https://orcid.org/0000-0001-5951-6819)
- Jooil Kim (ORCID: https://orcid.org/0000-0002-2610-4882)
- Simon O’Doherty (ORCID: https://orcid.org/0000-0002-4051-6760)
- Paul B. Krummel (ORCID: https://orcid.org/0000-0002-4884-3678)
- Matthew Rigby (ORCID: https://orcid.org/0000-0002-2020-9253)
- Sunyoung Park (ORCID: https://orcid.org/0000-0002-7506-5752)
- Hyeri Park (ORCID: https://orcid.org/0000-0001-7061-7856)
- Peter K. Salameh
- B.O. Adam (ORCID: https://orcid.org/0009-0004-9060-0612)
Institutions
- CSIRO Oceans and Atmosphere (AU)
- Scripps Institution of Oceanography (US)
- Kyungpook National University (KR)
- University of Bristol (GB)
- University of California San Diego (US)
- Massachusetts Institute of Technology (US)
Publication Details
- Journal
- Communications Earth & Environment
- Published
- 2024-12-21
- DOI
- https://doi.org/10.1038/s43247-024-01946-y
- Citations
- 5
- Primary Topic
- Atmospheric Ozone and Climate
- Type
- article
- Field-Weighted Citation Impact
- 1.88
Funders
- National Aeronautics and Space Administration
- Department for Business, Energy and Industrial Strategy, UK Government
- Sight Research UK
- European Commission
- University of Bristol
- Commonwealth Scientific and Industrial Research Organisation
- National Research Foundation
- Nuclear Safety and Security Commission
- National Research Foundation of Korea
- Ministry of Science and ICT, South Korea
- National Oceanic and Atmospheric Administration
- Horizon 2020 Framework Programme
- Natural Environment Research Council