Rethinking time-lagged emissions and abatement potential of fluorocarbons in the post-Kigali Amendment era

• Published in: Nature communications Vol. 15; no. 1; pp. 6687 - 10
• Main Authors: Liu, Heping, Duan, Huabo, Zhang, Ning, Ma, Yin, Liu, Gang, Miller, Travis Reed, Mao, Ruichang, Xu, Ming, Li, Jinhui, Yang, Jiakuan
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group 06.08.2024; Nature Publishing Group UK; Nature Portfolio
• Subjects: Carbon dioxide; Climate change; Decarbonization; Emission; Emission measurements; Emissions; Equivalence; Fluorocarbons; Global warming; Hydrochlorofluorocarbons; Hydrofluorocarbons; Montreal Protocol; Ozone; Ozone depletion; Ozone layer; Ozonosphere; Perfluorocarbons; Time measurement
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-024-51113-2

The Montreal Protocol has been successful in safeguarding the ozone layer and curbing climate change. However, accurately estimating and reducing the time-lagged emissions of ozone-depleting substances or their substitutes, such as produced but not-yet-emitted fluorocarbon banks, remains a significant challenge. Here, we use a dynamic material flow analysis model to characterize the global stocks and flows of two fluorocarbon categories, hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs), from 1986 to 2060. We assess emission pathways, time-lagged emission sizes, and potential abatement measures throughout different life cycle stages while focusing on the role of banked fluorocarbons in global and regional decarbonization efforts in the post-Kigali Amendment era. Although fluorocarbon releases are expected to decline, the cumulative global warming potential (GWP)-weighted emissions of HCFCs and HFCs are significant; these will be 6.4 (±1.2) and 14.8 (±2.5) gigatons CO2-equivalent, respectively, in 2022–2060 in our business-as-usual (BAU) scenario. Scenario analysis demonstrates that implementing currently available best environmental practices in developed economies can reduce cumulative GWP-weighted emissions by up to 45% compared with the BAU scenario.The cumulative global warming potential-weighted emissions of hydrochlorofluorocarbons and hydrofluorocarbons are significant, which will be 21.2 (±3.7) gigatons CO2-equivalent in 2022–2060 under a business-as-usual scenario.