Sustained Decline in CFC-12 Emissions from China: Evidence for Successful Phase-out under the Montreal Protocol and Global Implications
Ma, Mengyue Chen, Ye Tan, Li Ye, Tong Zhang, Linlin Lu, Yuanyuan Jin, Shengjia Li, Bowei Hu, Yunxing Yu, Haibo
Ma, Mengyue
Chen, Ye
Tan, Li
Ye, Tong
Zhang, Linlin
Lu, Yuanyuan
Jin, Shengjia
Li, Bowei
Hu, Yunxing
Yu, Haibo
Series / Report no.
Open Access
Type
Journal Article
Article
Article
Language
en
Date
2026-01-02
Research Projects
Organizational Units
Journal Issue
Title
Sustained Decline in CFC-12 Emissions from China: Evidence for Successful Phase-out under the Montreal Protocol and Global Implications
Translated Title
Published in
Environ Sci Technol 2026; 60(2):1791-1799
Abstract
The production and consumption of CFC-12 (dichlorodifluoromethane; CClF), a major ozone-depleting substance and potent greenhouse gas, were globally phased out by 2010 under the Montreal Protocol. Observation-based (top-down) verification of this phase-out requires quantification of the CFC-12 emissions using atmospheric observations, which have been notably lacking post-2020 for China. In this study, 6814 new high-frequency atmospheric observations of CFC-12 from three Chinese stations in 2024 were analyzed. Combining these observations with inverse modeling, we quantified China's most recent CFC-12 emissions and revealed a 72% decline, from 12.7 ± 2.2 gigagrams per year (Gg yr) in 2016 to 3.6 ± 0.8 Gg yr in 2024. We also developed a new bottom-up inventory, which generally reconciles the discrepancy between observation-based estimates and previous inventories. From a global perspective, this study provides the first country-specific, observation-based estimates of CFC-12 emissions for 2024, accounting for 22.6% of the global CFC-12 emissions. In contrast, for other countries, no observation-based CFC-12 emissions exist, or only a few pre-2022 data are available. Approximately three-quarters (77.4%) of global CFC-12 emissions remain unattributed. These findings highlight both China's success in mitigating CFC-12 emissions, contributing to ozone layer protection and climate mitigation, and the need for enhanced emission quantification across other regions.