Abstract

We assess scientific evidence that has emerged since the U.S. Environmental Protection Agency’s 2009 Endangerment Finding for six well-mixed greenhouse gases, and find that this new evidence lends increased support to the conclusion that these gases pose a danger to public health and welfare. Newly available evidence about a wide range of observed and projected impacts strengthens the association between risk of some of these impacts and anthropogenic climate change; indicates that some impacts or combinations of impacts have the potential to be more severe than previously understood; and identifies substantial risk of additional impacts through processes and pathways not considered in the endangerment finding. This research, co-authored by Lab co-director Solomon Hsiang of the University of California’s Goldman School, points to evidence from a number of academic contributions by members of our research team.