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.