Worldwide inference of national methane emissions by inversion of satellite observations with UNFCCC prior estimates

Using an open-source, high-resolution inversion of 2023 TROPOMI and GHGSat satellite data (IMI 2.0) at up to 25-km resolution for 161 countries, researchers estimate global methane emissions of 598 Tg yr−1 with anthropogenic emissions of 375 Tg yr−1—about 15% above UNFCCC-reported totals (32% higher for oil & gas) and with national emissions more than 50% higher than reporting in one quarter of countries; hydroelectric reservoirs (not usually reported) add ~6% of anthropogenic emissions. China, the U.S., India and Brazil account for 39% of anthropogenic methane, major upward corrections are found in the U.S., Venezuela, India and Turkmenistan (driven largely by oil‑gas and livestock), oil‑gas methane intensities vary by two orders of magnitude and five countries already meet the 0.2% industry target—if universally met oil‑gas emissions could fall ~81% to ~11 Tg yr−1. The dataset provides a reproducible, annually updatable framework to benchmark and target mitigation and to scrutinize national NDCs, although results carry regional uncertainties (notably at high latitudes and in persistently cloudy tropical regions) that limit attribution in some countries such as Russia and Indonesia.

Analysis

Researchers used an open-source high-resolution inversion (IMI 2.0) of 2023 TROPOMI blended with GOSAT plus GHGSat point-source information to estimate global methane at 598 (475–625) Tg a−1 and anthropogenic methane at 375 (299–392) Tg a−1, which is 15% above the summed UNFCCC prior (326 Tg a−1) and 32% higher for the oil‑and‑gas sector; hydroelectric reservoirs, typically omitted from UNFCCC reports, add ~6% of anthropogenic emissions. China (59 Tg a−1), the U.S. (36 Tg a−1), India (28 Tg a−1) and Brazil (22 Tg a−1) account for 39% of anthropogenic emissions, while the inversion produces large upward country corrections (U.S. +8.0 Tg, Venezuela +6.4 Tg, India +6.0 Tg, Turkmenistan +5.4 Tg) and notable decreases (Russia −4.8 Tg), highlighting material misreporting in many national inventories. Oil‑gas methane intensities span more than two orders of magnitude with five countries meeting the OGCI 0.2% target (including Norway and Qatar) and several countries (Venezuela 25%, Ukraine 15%, Colombia 15%, Turkmenistan 10%) exhibiting very high intensities, implying concentrated regulatory and reputational risk. The dataset is reproducible and annualizable, improving tools for policy enforcement and corporate due diligence, but attribution and magnitude retain regional uncertainties—particularly at high latitudes and in persistently cloudy tropical regions (Russia, Indonesia) and where wetland–anthropogenic spatial overlap exists—so investors should weight signals by reported averaging‑kernel sensitivities and ensemble ranges.

Key Decisions for Investors

• Reassess exposure to upstream oil‑and‑gas sovereign and corporate issuers in countries identified with high methane intensities (Venezuela, Turkmenistan, Ukraine, Colombia) and favour lower‑intensity producers or companies with verifiable leak‑reduction plans,
• Increase allocation to or diligence on methane detection and abatement technologies and service providers (satellite monitoring, leak detection, capture solutions) because more robust, reproducible monitoring makes mitigation performance a measurable value driver and potential regulatory requirement,
• Use the IMI 2.0 country‑level results to stress‑test portfolio transition and disclosure risk, require satellite‑consistent emissions reporting from counterparties, and set watch‑list triggers to hedge or reduce positions when annual posterior estimates materially diverge from UNFCCC‑reported inventories