evidence: To prove this point, Kahan tested Republicans and Democrats on their scientific knowledge of global warming. He found that an overwhelming majority of both Republicans and Democrats know scientists believe CO2 causes global temperatures to rise. They also know that scientists believe that human-caused global warming leads to coastal flooding, rising temperatures and other ill effects. [...] Even assuming the consensus message does work, it will not necessarily lead to climate action by policymakers, said Mike Hulme, professor of climate and culture at King's College London. "Even if one takes the Cook et al. study at face value then how does a scientific consensus of 97.1 percent make policy-making about climate change any easier?" he wrote in an upcoming book on the consensus that he shared with ClimateWire.