Recent research has unveiled a troubling surge in the emission of powerful greenhouse gases in China, posing a serious challenge to global climate goals. According to two pivotal studies, China has significantly contributed to the rise in atmospheric levels of perfluorocarbons, which are notorious for their high global warming potential. These findings, published in Proceedings of the National Academy of Sciences and Environmental Science & Technology, focus on three specific PFCs: tetrafluoromethane PFC-14, hexafluoroethane PFC-116, and perfluorocyclobutane PFC-318.
The study published in PNAS reveals that emissions of PFC-14 and PFC-116 from China increased by 78% between 2011 and 2021. The primary sources of these emissions are found in the less-populated western regions of China, where aluminum production is concentrated. Additionally, the semiconductor industry in the more developed eastern regions contributes to these emissions. PFC-14 and PFC-116 are released as byproducts during aluminum smelting and semiconductor production. This dramatic rise in emissions from these sectors accounts for a significant portion of the global increase in these gases.
Meanwhile, the research featured in Environmental Science & Technology reports a 70% increase in emissions of PFC-318 from 2011 to 2020. This increase is predominantly from eastern China, where factories manufacturing polytetrafluoroethylene (PTFE) are major contributors. PFC-318, a byproduct of PTFE production, is used in nonstick coatings for cookware and other industrial applications. The overlap of high PFC-318 emissions with PTFE-producing regions suggests that these factories are key sources of this potent greenhouse gas.
Minde An, a postdoctoral researcher at the MIT Center for Global Change Science and lead author of both studies, emphasizes the importance of identifying the precise sources of these emissions. By using atmospheric observations and advanced modeling techniques, the studies not only quantify the magnitude of PFC emissions but also locate their industrial origins. This detailed understanding can guide the development of targeted mitigation strategies to address these emissions effectively.
MIT’s Ronald Prinn, a professor of atmospheric sciences and director of both the MIT Joint Program on the Science and Policy of Global Change and CGCS, co-authored both studies. He stresses the critical need to phase out PFC emissions to meet global climate targets. Phasing out these emissions is feasible through improved recycling programs and technological advancements in industries that produce these gases as byproducts.
The studies utilized atmospheric data from nine monitoring stations across China, including one from the Advanced Global Atmospheric Gases Experiment (AGAGE) network. Comparisons with data from five globally distributed background AGAGE stations helped to assess the global impact of Chinese PFC emissions. These comprehensive observations reveal a significant increase in global levels of PFCs due to China's industrial activities.
As the world seeks to limit global warming to 1.5 degrees Celsius above pre-industrial levels, the rising emissions of potent greenhouse gases from China present a formidable challenge. Addressing this issue requires international cooperation and effective policies to reduce emissions from key industrial sources. The research underscores the urgent need for targeted actions to mitigate the environmental impact of these persistent and highly potent gases.
