A full 97% of researchers taking a stance on climate change say it's man-made, as do 97-98% of the most frequently-published climate scientists. But according to Wisconsin Rep. Paul Ryan, they're all wrong. When asked during an election debate Monday if he believed humans cause climate change, the former Republican vice presidential nominee joined the growing number of Republicans who refuse to acknowledge the overwhelming scientific consensus that humans are influencing the Earth's climate. "I don't know the answer to that question," he said according to the Associated Press. "I don't think science does, either."
In fact, science does know the answer. Climate scientists believe with a 95 percent level of certainty (the same level of certainty as their belief in the dangers of cigarette smoking) that human activity is contributing to climate change. There are things science knows, and this is one of them. Scientists may not have the answer to what policies are appropriate for responding to the fact that greenhouse-gas emissions cause changes to the environment, but they can tell us what happens when we release heat-trapping gasses into the atmosphere. This is another way of saying that Paul Ryan is a nut. His ideological fantasies prevent him from accepting even basic scientific facts."