Mapping the changes of CH₄ emissions in global supply chains

Area of Science:

• Environmental Science
• Climate Change Research
• Supply Chain Analysis

Background:

• Methane (CH4) is a potent greenhouse gas contributing significantly to global climate change.
• Understanding CH4 emission flows within global supply chains is crucial for effective climate mitigation strategies.
• Previous research has often focused on production-based emissions, neglecting the complexities of consumption-based accounting and trade flows.

Purpose of the Study:

• To identify methane (CH4) emission flows along global supply chains from both production- and consumption-based perspectives.
• To analyze the temporal changes in these CH4 emission flows between 2000 and 2014.
• To pinpoint key sectors and regions contributing to CH4 emissions within global trade networks.

Main Methods:

• Employed the structural path analysis (SPA) method to trace embodied CH4 emissions.
• Examined inter-sectoral and inter-regional supply chain linkages.
• Analyzed data spanning from 2000 to 2014 to capture temporal dynamics.

Main Results:

• Agriculture and Construction were major contributors to CH4 emission increases.
• Agriculture and Mining dominated embodied CH4 trade at the final consumption tier.
• Food and Heavy Manufacturing sectors were significant in intermediate goods trade for CH4 emissions.
• The US was the largest importer of embodied CH4 in 2000, while China dominated in 2014.
• China's 2014 CH4 emissions were largely linked to intermediate production; India became the largest direct emitter.

Conclusions:

• Sectoral differences in CH4 abatement potential exist along global supply chains.
• Shifting import dominance from the US to China reflects evolving global industrial patterns.
• Industrial upgrading in China significantly influenced its embodied CH4 emissions.
• Findings support a more justified allocation of reduction responsibilities between connected countries and sectors.