Strengthening the link between scientific research and official greenhouse gas (GHG) reporting is an important step under the Paris Agreement’s Enhanced Transparency Framework. The PARIS Project, funded by Horizon Europe, is working with eight European countries to develop practical tools for this purpose.

One of these tools is a set of draft annexes designed to complement National Inventory Documents (NIDs). These annexes create a structured way to integrate findings from atmospheric science—such as inverse modelling—into the national reporting process.

Purpose of the Annexes

The annexes are designed as optional supplements to National Inventory Documents. They do not replace established national methodologies. Instead, they provide:

• A format for including new scientific insights in a transparent manner.
• Comparisons between inventory-based estimates and scientific reference estimates.
• Additional context for understanding uncertainties and methodological choices.

By enabling this structured exchange, the annexes enhance clarity, support consistency, and show how scientific approaches can complement official reporting. Where scientific and inventory-based estimates differ, the annexes highlight opportunities to improve data and methods.

Structure and Content

The draft annexes use a consistent framework across participating countries while allowing flexibility for national circumstances. Core sections include:

• Key category analysis – identifying sectors or gases that contribute most to national totals.
• Uncertainty assessments – combining national data with research-based evaluations, to provide a fuller picture of confidence levels.
• Comparisons with scientific reference estimates – including first applications of top-down (atmospheric) methods.
• Methodological explanations – outlining recalculations and improvements.
• Quality assurance and control (QA/QC) – documenting steps to maintain reliability.
• Standardized reporting tables – aligned with UNFCCC Common Reporting Tables (CRTs).

This structure ensures comparability across countries while supporting country-specific research collaborations.

Relevance for Policymakers and Researchers

For policymakers, the annexes provide a clear view of how independent scientific assessments relate to official inventories. They highlight where further attention or research may be useful, without requiring immediate changes to formal reporting rules.

For researchers, the annexes establish a recognized pathway for contributing to inventories in line with institutional and legal frameworks. They also promote cooperation between inventory agencies and the scientific community, particularly in interpreting atmospheric and modelling results.

Looking Ahead

The annexes developed under the PARIS Project are pilot versions that will be refined annually as new data and collaborations emerge. This allows them to evolve alongside scientific advances while remaining aligned with national reporting practices.

In this way, the annexes serve as a practical bridge between science and policy. By providing a transparent, structured, and policy-relevant channel for integrating research into inventories, they strengthen the robustness of GHG reporting and help countries meet the requirements of the Paris Agreement.