Duality in climate science

Delivery of palatable 2 °C mitigation scenarios depends on speculative negative emissions or changing the past. Scientists must make their assumptions transparent and defensible, however politically uncomfortable the conclusions.

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I thank G. Peters and R. Andrew from CICERO, Oslo, for guidance with the IPCC scenario database and global cement emissions, respectively; K. West from the IEA, Paris, for information related to IEA cement scenarios; and M. Sharmina and J. Kuriakose for deforestation scenarios, and A. Bows-Larkin and J. Broderick for carbon budgets, from the Tyndall Centre, Univ. Manchester.

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  1. Kevin Anderson is at the Tyndall Centre for Climate Change Research, University of Manchester, Pariser Building, Sackville Street, Manchester M13 9PL, UK

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Correspondence to Kevin Anderson.