Comparing emissions scenarios is an essential part of mitigation analysis, as climate targets can be met in various ways with different economic, energy system and co-benefit implications. Typically, a central ‘reference scenario’ acts as a point of comparison, and often this has been a no policy baseline with no explicit mitigative action taken. The use of such baselines is under increasing scrutiny, raising a wider question around the appropriate use of reference scenarios in mitigation analysis. In this Perspective, we assess three critical issues relevant to the use of reference scenarios, demonstrating how different policy contexts merit the use of different scenarios. We provide recommendations to the modelling community on best practice in the creation, use and communication of reference scenarios.
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N.G. was supported by the Natural Environment Research Council (NERC) (grant no. NE/L002515/1) as well as the Department for Business, Energy and Industrial Strategy (BEIS). A.G. and A.H. acknowledge support from the H2020 European Commission Project PARIS REINFORCE (grant no. 820846). N.G. thanks the Science and Solutions for a Changing Planet Doctoral Training Partnership at the Grantham Institute for support during their PhD studies. We thank J. Rogelj and S. Dietz for insightful comments on an earlier draft. The authors take sole responsibility for the final content of the Perspective.
The authors declare no competing interests.
Peer review information Nature Climate Change thanks Hadi Dowlatabadi, Vanessa Schweizer and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.
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Grant, N., Hawkes, A., Napp, T. et al. The appropriate use of reference scenarios in mitigation analysis. Nat. Clim. Chang. 10, 605–610 (2020). https://doi.org/10.1038/s41558-020-0826-9
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