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arXiv · 2607.16931

Satellite-based emissions estimate indicates progress toward China's methane mitigation goals

Abstract

China emits the most methane of any country worldwide, but there are large uncertainties in recent emissions trends, sources, and the potential impacts of policy actions. This study focuses on a period when the government initiated ambitious methane control efforts, linking sectoral policies with atmospheric evidence on sectoral, sub-national, and seasonal emissions during 2019--2024. We quantify daily methane emissions from China using a regional atmospheric inverse model with TROPOMI satellite observations. Our results reveal an average methane emissions increase rate of 0.3 Tg yr$^{-2}$ in Eastern & Central China, likely a milder trend than in the 2010s. Coal industry methane emissions intensity declined for the first time (-3.2% yr$^{-1}$) despite rising production, possibly associated with diverse policy instruments, mandates, and incentives. We further highlight two emerging challenges for future mitigation: leaks from expanding urban gas use amid the energy transition and rising agricultural emission yet with substantial uncertainty in estimates. Lastly, declining emissions intensity of coal mines points to the future role of targeted mandates and incentives in encouraging methane reduction for other sectors.

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Ziting Huang, Ao Chen, Leyang Feng, William S. Daniels, Dylan C. Gaeta, Kristan L. Morgan, Lee T. Murray, Xueying Yu, Benjamin F. Hobbs, Scot M. Miller. 2026-07-18. Satellite-based emissions estimate indicates progress toward China's methane mitigation goals. https://arxiv.org/abs/2607.16931

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