亚开行-减少中华人民共和国农业甲烷排放（英）

ADB BRIEFSReducing Methane Emissions from Agriculture in the People’s Republic of ChinaKEY POINTS• Agricultural methane emissions from livestock and rice cultivation in the People’s Republic of China (PRC) constitute a substantial portion of national and global methane totals. Addressing these emissions is crucial, given methane’s high warming potential and short atmospheric lifetime, providing immediate climate benefits.• Although mature mitigation technologies and supportive policies exist, widespread implementation in the PRC faces significant barriers including limited financial resources, insufficient farmer knowledge and training, entrenched agricultural practices, and inadequate institutional capacity.• Effective methane mitigation requires an integrated policy framework focused on institutional reforms, targeted financial incentives, extensive capacity building initiatives, and proactive behavioral change approaches.Dustin SchinnClimate Change SpecialistAsian Development Bank (ADB)INTRODUCTIONWhen discussing climate change, attention often gravitates toward carbon dioxide (CO2) since, by mass, the amount released into the atmosphere dwarfs that of methane (CH4) or other greenhouse gases (GHGs) like nitrous oxide by several orders of magnitude. Recent estimates place total annual global CO2 emissions at approximately 41–42 gigatons (Gt), with 94% coming from fossil fuels, and the remainder from industrial processes and waste management.1 In contrast, total annual global CH4 emissions (from both natural and human sources) are estimated to be around 580–600 megatons (Mt).2 Since 1990, total CO2 amounted to 37,098 Mt, whereas CH4 emissions totaled 315 Mt—a mere 0.85% of CO2 (Table 1).3However, mass does not reflect the climate impact. CH4 is responsible for roughly one-fourth (0.42°C) of the net global warming since the Industrial Revolution—a significant contribution to the warming of our planet.4 Translating CH4 into CO2-equivalent terms, 315 MT of CH4 exert a warming impact similar to nearly 8,557 megatons of carbon dioxide equivalent (MtCO2e), i.e., approximately a quarter of all CO2 released since 1990.Note: ADB recognizes “China” as the People’s Republic of China.1 A. Bashir et al. 2024. Comprehensive Review of CO2 Geological Storage: Exploring Principles, Mechanisms, and Prospects. Earth-Science Reviews. 249. 104672; and Global Carbon Project. 2024. Fossil Fuel CO2 Emissions Increase Again in 2024. Global Carbon Budget. 13 November.2 W. J. Sawyer et al. 2022. Methane Emissions and Global Warming: Mitigation Technologies, Policy Ambitions, and Global Efforts. MIT Science Policy Review. 3. pp. 73–84; and X. Yu et al. 2023. A High-Resolution Satellite-Based Map of Global Methane Emissions Reveals Missing Wetland, Fossil Fuel, and Monsoon Sources. Atmospheric Chemistry and Physics. 23 (5). pp. 3325–3346.3 H. Ritchie, P. Rosado, and M. Roser. 2020. Breakdown of Carbon Dioxide, Methane and Nitrous Oxide Emissions by Sector. Our World in Dat