By Jesse Jenkins and Devon Swezey, originally at the Breakthrough InstituteForget 80% by 2050 and 17% by 2020. Time to stop fixating on 450 ppm vs 350 ppm. As UN climate talks kick off today in Copenhagen, Denmark, there's only one number really [...]










An update from 





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By Yael Borofsky and Jesse Jenkins, originally posted at 


