Reducing Methane Emissions Along Global Natural Gas Supply Chain through Import Standards

<title>Abstract</title> <p>Rapidly reducing energy sector methane (CH₄) emissions is the most critical mitigation strategy to limit near-term warming. As natural gas (NG) increasingly trades across supply chains, policy measures such as methane-intensity-based import standards can tackle upstream emissions that fall outside importers’ domestic regulation authorities. Using a global integrated assessment model (GCAM-v8.2-CGS) with explicit representation of bilateral pipeline and LNG trade flows and improved representation of regional methane emissions across the supply chain, this study assesses the effectiveness of import standards under alternative energy transition, trade, and CH₄ mitigation scenarios. We find that import standards can reduce CH₄ emissions along the NG supply chain for major importers by 58% in 2035 and by 64% in 2060 from the reference by shifting from high-intensity to low-intensity NG suppliers. However, global reductions only reach 30% because high-intensity supply is redirected to unconstrained markets. Combining import standards with either accelerated energy transition under net-zero targets or broader producer-side methane abatement helps reduce emissions leakage to achieve deeper and sustained global reductions.</p>