Non-state and subnational climate actors have become central to global climate change governance. Quantitatively assessing climate mitigation undertaken by these entities is critical to understand the credibility of this trend. In this Perspective, we make recommendations regarding five main areas of research and methodological development related to evaluating non-state and subnational climate actions: defining clear boundaries and terminology; use of common methodologies to aggregate and assess non-state and subnational contributions; systematically dealing with issues of overlap; estimating the likelihood of implementation; and addressing data gaps.
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We thank participants at an April 2017 workshop held at University College London in London, UK, as well as a November 2017 workshop in Bonn, Germany, who provided feedback on early thinking and drafts of this paper. This work was funded by ClimateWorks Foundation grant no. 17-1101.
The authors declare no competing interests.
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Hsu, A., Höhne, N., Kuramochi, T. et al. A research roadmap for quantifying non-state and subnational climate mitigation action. Nature Clim Change 9, 11–17 (2019). https://doi.org/10.1038/s41558-018-0338-z
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