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Ethical choices behind quantifications of fair contributions under the Paris Agreement


The Parties to the UNFCCC and Paris Agreement agreed to act on the basis of equity to protect the climate system. Equitable effort sharing is an irreducibly normative matter, yet some influential studies have sought to create quantitative indicators of equitable effort that claim to be value-neutral (despite evident biases). Many of these studies fail to clarify the ethical principles underlying their indicators, some mislabel approaches that favour wealthy nations as ‘equity approaches’ and some combine contradictory indicators into composites we call derivative benchmarks. This Perspective reviews influential climate effort-sharing assessments and presents guidelines for developing and adjudicating policy-relevant (but not ethically neutral) equity research.

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Fig. 1: Equity principles included in studies presented as value-neutral.
Fig. 2: Equity principles included in studies presented as ethically explicit.


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Authors and Affiliations



All authors contributed to the conception of the work. K.D., C.H., S. Kartha, S. Klinsky, H.S., T.R. and H.W. jointly wrote the paper. K.D., C.H., S. Kartha and G.H. contributed to the analysis and interpretation of data, including the figures. All authors contributed to discussions of revisions and improvements to this paper.

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Correspondence to Kate Dooley.

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Peer review information Nature Climate Change thanks Sudhir Rajan, Narasimha Rao, Steve Vanderheiden and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary Data 1

Supplementary data containing Supplementary Tables 1 (Overview of reviewed studies) and 2 (Analysis for Figs. 1 and 2).

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Dooley, K., Holz, C., Kartha, S. et al. Ethical choices behind quantifications of fair contributions under the Paris Agreement. Nat. Clim. Chang. 11, 300–305 (2021).

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