Uncovering external drivers of methane emissions in China: a multi-perspective input-output analysis of key emission sources

Abstract As the world’s largest methane (CH 4 ) emitter, China’s efforts in CH 4 mitigation are crucial for global climate action. Existing studies primarily focus on sector-specific internal mitigation from a production-side perspective, while understanding the external drivers of CH 4 emissions from a consumption-side perspective is essential for developing effective mitigation strategies. This study establishes an integrated analytical framework combining the environmentally extended input-output (EEIO) model, structural path analysis (SPA), and structural decomposition analysis (SDA) to examine how external economic activities affect CH 4 emissions from China’s key emission sources (energy and agricultural activities) between 2002 and 2017 at sectoral, supply chain, and socioeconomic levels. Our findings reveal that most energy-CH 4 emissions are induced by the final demand of the construction sector through indirect paths involving multiple intermediate steps. In contrast, agricultural-CH 4 emissions are largely driven directly by final demand, while a significant proportion is also induced through indirect paths by the food & tobacco sector. Additionally, several key supply chain pathways are identified as major contributors to both energy-CH 4 and agriculture-CH 4 emissions. The SDA results highlight that the effects of capital formation, export, and urban household consumption are the main drivers of increased CH 4 emissions, while the emission intensity effect and the production structure effect play a crucial role in mitigating emission growth. Moreover, the driving mechanisms exhibit significant variations across different time periods and emission sources, particularly in oil&gas-CH 4 and livestock-CH 4 . These findings suggest that China needs to adopt a diversified policy mix that integrates sector-specific, supply chain-wide, and socioeconomic considerations to achieve more effective CH 4 mitigation.