Nature Climate Change, Published online: 28 August 2025; doi:10.1038/s41558-025-02412-z
IPCC assessments are of limited use to the UNFCCC policy process due to misalignment and lack of relevance, with the situation further exacerbated by the UNFCCC’s weak scientific uptake mechanisms. The interface between the IPCC and the UNFCCC urgently needs to be reformed to facilitate a more effective science–policy connection.