China's CH2Cl2 emissions reached 931 Gg in 2024, 303 Gg above 2019, inferred from atmospheric observations
A Nature Communications study estimates China's dichloromethane emissions at 931 ± 107 Gg per year in 2024. Growth accelerated after 2019 despite restrictions on use, which matters for ozone layer recovery.
A team from Zhejiang University, the China National Environmental Monitoring Centre and several other institutions estimated dichloromethane (CH2Cl2) emissions in China from atmospheric observations. The paper was published in Nature Communications on 6 November 2026. According to the authors, emissions in China were 931 ± 107 gigagrams per year (Gg yr−1) in 2024 nature.com
Nature Communicationsnature.comOpen source ↗. This is 303 ± 111 Gg yr−1 more than in 2019.
Emission growth after 2019
The authors report an average growth rate of 67.0 ± 15.2 Gg yr−2 for 2019–2024. The previously reported rate for 2011–2019 was 42.0 ± 8.1 Gg yr−2. Growth therefore became faster, although some measures restricting CH2Cl2 use in China have been in force since 2020.
The study also shows that the share of China in global CH2Cl2 emissions rose from 2011 to 2024. The authors acknowledge an earlier study by An et al., which served as an important reference for historical emission estimates in China.
Why dichloromethane matters for the ozone layer
The importance of CH2Cl2 for stratospheric ozone has grown in recent years, and China was suspected of contributing to global emissions nature.com
Nature Communicationsnature.comOpen source ↗. However, Chinese emissions after 2019 remained poorly constrained. The new estimate for 2024 addresses this gap.
The authors conclude that the results highlight the importance of continued monitoring and mitigation of CH2Cl2 emissions in the context of ozone layer recovery.
Research team
The corresponding author is Xuekun Fang of the State Key Laboratory of Soil Pollution Control and Safety at Zhejiang University in Hangzhou. Co-authors work at Henan University, the Chengdu University of Information Technology, the National Research Center of Environmental Analysis and Measurement in Beijing and the company Beijing Huanaco Innovation. Five authors are listed as having contributed equally: Bowei Li, Chunrong Chen, Ye Chen, Li Tan and Zhixiao Yao.
