U.S. National Academy of Sciences labels as "settled facts" that "the Earth system is warming and that much of this warming is very likely due to human activities" - New report confirms failure to act poses "significant risks"

A strong, credible body of scientific evidence shows that climate change is occurring, is caused largely by human activities, and poses significant risks for a broad range of human and natural systems….

Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small. Such conclusions and theories are then regarded as settled...