Too many losses and too few gains: declining forest-sector Carbon Dioxide Removals in Europe's GHG accounts

European forests are considered crucial to achieving climate neutrality by 2050. The effectiveness of forests and harvested wood products in generating carbon dioxide removals (CDR) is currently debated. Greenhouse gas inventories (GHGIs) are the most important means for assessing compliance with climate goals. We analysed the GHGI submissions of 22 EU Member States, Norway, Switzerland, and the UK to the UNFCCC to track the historical development of forest tree biomass and harvested wood product pools. Our analysis reveals a recent decline in the effectiveness of forest-based mitigation, driven by two processes: an increase of forest tree biomass losses and a reduced efficiency of carbon transfer from biomass to wood products. Moreover, the current approaches of GHG reporting significantly degrade the capacity and motivation of EU Member States to fully harness the mitigation potential of forests. Addressing these limitations is critical for effective EU climate action involving forest-based CDR, and fair accounting and effort sharing.