The 2014 U.S. National Climate Assessment states: “the global warming of the past 50 years is primarily due to human activities, predominantly the burning of fossil fuels. Many independent lines of evidence confirm that human activities are affecting climate in unprecedented ways.”
Currently, half of Americans (52%) think that global warming, if it is happening, is mostly human caused. By contrast, one in three (32%) say they think it is due mostly to natural changes in the environment. Public understanding and acceptance of the human contribution to global warming has fluctuated over the past several years, but is currently 5 percentage points higher than in May 2011, while belief that global warming is naturally caused is 3 points lower.
In the latest study investigating the degree of scientific consensus on climate change, Cook and colleagues (2013) examined nearly 12,000 peer-reviewed papers in the climate science literature and found that of those papers that stated a position on the reality of human-caused global warming, 97% said it is happening and at least partly human caused.
Public understanding of climate change, however, is starkly different than the expert consensus: only 44% of Americans think global warming is both happening and human caused.
Moreover, only one in ten Americans (12%) know that 90% or more scientists have concluded human-caused global warming is happening. As many Americans – (14%) – think fewer than half of climate scientists have reached this conclusion. Another three in ten Americans (29%) say they “don’t know” (28%) or didn’t answer the question (1%).
This public misunderstanding of the degree of scientific consensus has significant consequences. Other research has identified public understanding of the scientific consensus as a critical “gateway belief” that influences other important beliefs (i.e., global warming is happening, human caused, a serious problem, and solvable) and support for action.
For further information, see: Ding et al. (2011); Lewandowsky et al. (2013); and McCright et al. (2013).
This climate note is based on findings from a nationally representative survey – Climate Change in the American Mind – conducted by the Yale Project on Climate Change Communication and the George Mason University Center for Climate Change Communication. Interview dates: April 11 – 21, 2014. Interviews: 1,013 Adults (18+). Total average margin of error: +/- 3 percentage points at the 95% confidence level. This research was funded by the U.S. Energy Foundation, the 11th Hour Project, the Grantham Foundation, and the V.K. Rasmussen Foundation.
For more findings from our latest poll, go to Climate Change in the American Mind, April 2014.