JRC Publications Reports New GHG Budget Approach for 1.5°C Goal

On October 22, 2026, JRC Publications reported a new approach for determining national greenhouse gas budgets that aligns with the 1.5°C goal of the Paris Agreement while matching national inventory accounting methods.

The proposed framework bridges global mitigation assessments and national inventories to design transparent Nationally Determined Contributions. Developed by Antti-Ilari Partanen, Tommi Ekholm, Jyri Seppälä, Sally Weaver, Taru Palosuo, Giacomo Grassi, Chris Smith, Kati Kulovesi, Hannele Laine, and Markku Ollikainen, the methodology translates CO2-warming-equivalent budgets by applying adjustment terms for non-CO2 greenhouse gases and land use, land-use change, and forestry sectors.

According to the published study, non-CO2 adjustments equal the bias introduced when estimating CO2-warming-equivalent emissions using Global Warming Potentials. Land use adjustments account for projected indirect effects on managed lands driven by climate change and CO2 fertilization.

Global Versus National Level Adjustments

Countries can apply these adjustments at either the global or national level. This choice directly alters a nation’s assigned greenhouse gas budget based on its specific emissions profile.

Finland serves as a prime demonstration in the report. The country’s greenhouse gas budget expands significantly when adjustments occur at the global level rather than the national level, driven by its specific mix of non-CO2 emissions and indirect effects.

Nationally adjusted budgets match a country’s fair share of warming contributions. Conversely, globally adjusted budgets show less sensitivity to modeling uncertainties tied to indirect effects and national emissions scenarios.

Application to Long-Term Climate Strategies

The methodology aims to strengthen the Global Stocktake of Nationally Determined Contributions under the Paris Agreement. Signatory countries can use the framework to evaluate their long-term climate strategies against globally consistent warming targets.

The research paper is accessible through the JRC Publications Repository, with detailed publisher documentation available via IOP Publishing.