HKS Authors

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Teresa and John Heinz Research Professor of Environmental Policy


John P. Holdren writes that because of the huge potential importance of the evidence of global climate change for policy and for human well-being on the largest scale, moreover, its details and its conclusions have been scrutinized and re-scrutinized to a staggering degree. It was the conclusions based on this evidence, made even more robust by the continuing growth of climate-related damages in the ensuing years, that motivated 195 countries  to sign the Paris Agreement in December 2015. The science was rightly considered "settled enough."


Holdren, John P. "Settled enough: Climate science, skepticism, and prudence." The Hill, May 24, 2021.