AI 中文总结
研究聚焦中国政府大力控制甲烷排放阶段，用区域大气反演模型和卫星观测量化排放。发现东部和中部地区排放增速变缓，煤炭行业排放强度首次下降，指出能源转型中城市燃气泄漏和农业排放估计不确定等挑战及煤矿减排措施的未来作用。
AI 中文摘要
中国是全球甲烷排放量最大的国家，但近期排放趋势、来源及政策行动的潜在影响存在很大不确定性。本研究聚焦于政府启动雄心勃勃的甲烷控制努力的时期，将部门政策与2019 - 2024年期间部门、次国家和季节性排放的大气证据联系起来。我们使用区域大气反演模型和TROPOMI卫星观测来量化中国的每日甲烷排放量。结果显示中国东部和中部地区甲烷排放平均增长率为0.3 Tg yr$^{-2}$，可能比2010年代趋势更温和。煤炭行业甲烷排放强度首次下降（-3.2% yr$^{-1}$）。我们还强调了未来减排的两个新挑战：能源转型中城市燃气使用增加导致的泄漏以及农业排放上升但估计存在很大不确定性。最后，煤矿排放强度下降表明有针对性的指令和激励措施在鼓励其他部门甲烷减排方面的未来作用。
英文摘要
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.
