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Recommendations for producing knowledge syntheses to inform climate change assessments

An Author Correction to this article was published on 23 June 2025

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Abstract

Climate change assessments (CCAs) play a critical role in taking stock of the available science and other forms of knowledge and informing policy processes. As the underlying evidence base increases exponentially, the complexity also increases and challenges CCA author teams to capture all the relevant knowledge. Therefore, CCAs will need to transition from predominantly assessing primary research to focusing on the assessment and critical appraisal of knowledge syntheses of such work, alongside capturing knowledges held outside traditional scientific sources. To support this, a stronger knowledge synthesis culture is needed, and we propose key recommendations and offer guidance for producing robust, transparent, reproducible, inclusive and timely syntheses that can inform CCAs across scales.

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Fig. 1: Proportion of climate literature cited by the IPCC.
Fig. 2: Recommendations for writing knowledge syntheses to inform climate change assessments.
Fig. 3: Key components for assessing confidence in evidence.

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Acknowledgements

We thank B. van den Hurk who commented on earlier versions of the paper. The work of J.D.F. was supported by UK Economic and Social Research Council (grant number ES/Z000114/1) and an ERC Advanced Grant (via the UKRI Horizon Europe guarantee scheme, EPSRC grant number EP/Z533385/1). The work of R.B. was supported through the Dutch Research Council (NWO grant number VI.Vidi.211.132). The work of J.C.M. and M.C. was supported by the European Research Council (ERC) under the European Union’s Horizon 2020 Framework Programme as part of the project ‘GeoEngineering and NegatIve Emissions pathways in Europe’ (GENIE) (grant agreement number 951542) as well as the project ‘Pathfinder 2: accelerating climate action for health’ funded by the Wellcome Trust (project-ID 227165/Z/23/Z).

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J.D.F., R.B., L.B.F., F.C., N.H., S.H., J.C.M., M.N., A.J.S., C.Z.-C. and M.C. conceptualized the Perspective. J.D.F. R.B. and L.B.F. wrote the original and final draft of the paper. J.C.M. and M.C. conducted analysis for Fig. 1. All authors provided input on the text.

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Correspondence to James D. Ford.

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Ford, J.D., Biesbroek, R., Ford, L.B. et al. Recommendations for producing knowledge syntheses to inform climate change assessments. Nat. Clim. Chang. 15, 698–708 (2025). https://doi.org/10.1038/s41558-025-02354-6

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