Targeting Ultra-Emitters for Effective Methane Mitigation in China’s Coal Sector

The energy system fuels climate change as the largest emitter of global greenhouse gases, while a lack of transparent, infrastructure-level information undermines efforts to cut emissions. Coal mining has been the largest emitter of methane (CH4) in China over the past 10 years, which is not tracked at the mine level, and effective mitigation pathways have yet to be established. Herein, we develop a state-of-the-art CH4 emission database, comprising 3343 active coal mines in China, by harmonizing multisource information. The results suggest that China's coal mines emitted 15.8 ± 5.1 million metric tons CH4 yr–1 in 2019. Those with CH4 emission intensities >2 standard deviations above the national mean accounted for 4% of China's coal production, yet they generated 23% of China's coal CH4 emissions. We project a steady decline in China's coal CH4 emissions by >75% in 2100 compared to 2019 levels under three different scenarios, due to reduced coal demand during energy transition. Targeting ultra-emitters for mine closure will accelerate emission reductions in the midterm and achieve deep CH4 emission cuts by >92% in 2100, which buys us time to control global warming. Our idealized mine closure strategy serves as a cost-effective CH4 mitigation strategy to enable swift climate action.