EYE-CLIMA: developing inverse modelling approaches for monitoring national GHG inventories

Emissions of greenhouse gases (GHG) reported by countries in their GHG inventories represent the central information used in international policies based on the Paris agreement and in the Global Stocktake process to help curb global GHG emissions. To maximize trust in these national emission inventories reported to the UNFCCC, procedures for quality control, quality assurance, and verification have been described in the IPCC 2006 national GHG inventory guidelines and extended further in its 2019 refinement. Quantifying emission fluxes via atmospheric measurements and inverse modelling provides an independent assessment of the inventories and can help determine the quality of national inventories and make improvements. While tested in scientific studies, routine applications of inverse modelling in national inventory reports are rare. As a new Horizon Europe project, EYE-CLIMA will perform inverse modelling of a range of important radiative forcers (methane, nitrous oxide, selected fluorinated gases, black carbon) as a monitoring tool on a national scale for selected European countries, together with national inventory agencies, to help develop complementary methods to ensure the robustness and lead to improvements in inventories. The presentation will lay out the overall project concept, including stakeholder involvement, and provide an overview on past experiences with inverse modelling approaches and strategies to implement them in a way useful for national inventory agencies.