Yale Program on Climate Change Communication

1. Global Warming Beliefs

1.1. Most Americans think global warming is happening.

Americans who think global warming is happening outnumber those who think it is not happening by a ratio of 6 to 1.

About seven in ten Americans (72%) think global warming is happening. By contrast, only 12% of Americans think global warming is not happening. Fifteen percent say they don’t know if global warming is happening (see data tables).

1.2. More than half of Americans are “extremely” or “very” sure global warming is happening. Very few are as sure it isn’t happening.

More than half of Americans (54%) are either “extremely” or “very” sure global warming is happening. Far fewer (7%) are “extremely” or “very” sure global warming is not happening.

1.3. A majority of Americans think global warming is mostly human-caused.

The Intergovernmental Panel on Climate Change’s Sixth Assessment report (2021), written and reviewed by thousands of climate experts worldwide, states: “It is unequivocal that human influence has warmed the atmosphere, ocean and land.” Intergovernmental Panel on Climate Change. (2021): Summary for Policymakers. In Masson-Delmotte, V., Zhai, P., Pirani, A., Connors, S. L., Péan, C., Berger, S., Caud, N., Chen, Y., Goldfarb, L., Gomis, M. I., Huang, M., Leitzell, K., Lonnoy, E., Matthews, J. B. R., Maycock, T. K., Waterfield, T., Yelekçi, O., Yu, R., & Zhou, B. (eds.), Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press.

More than half of Americans (56%) understand that global warming is mostly human-caused. By contrast, one in three (33%) think it is due mostly to natural changes in the environment.

1.4. A majority of Americans understand that most scientists think global warming is happening.

A 2016 review by John Cook and colleaguesCook, J., Oreskes, N., Doran, P. T., Anderegg, W. R. I., Verheggen, B., Maibach, E. W., Carlton, J. S., Lewandowsky, S., Skuce, A. G., Green, S. A., Nuccitelli, D., Jacobs, P., Richardson, M., Winkler, B., Painting, R., & Rice., K. (2016). Consensus on consensus: A synthesis of consensus estimates on human-caused global warming. Environmental Research Letters, 11(4). doi10.1088/1748-9326/11/4/048002 found that six independent, peer-reviewed studies examining the extent of the scientific consensus about global warming have concluded that between 90% and 100% of climate scientists are convinced that human-caused global warming is happening. A more recent study found that as many as 98% of climate scientists are convinced that global warming is happening and human-caused.Myers, K. F., Doran, P. T., Cook, J., Kotcher, J. E., & Myers, T. A. (2021). Consensus revisited: Quantifying scientific agreement on climate change and climate expertise among Earth scientists 10 years later. Environmental Research Letters, 16(10). doi:10.1088/1748-9326/ac2774

A majority of Americans (55%) understand that most scientists think global warming is happening. By contrast, one in four Americans (25%) think there is a lot of disagreement among scientists about whether or not global warming is happening. Very few Americans (2%) believe that most scientists think global warming is not happening.

1.5. One in five Americans understand that almost all climate scientists (more than 90%) have concluded that human-caused global warming is happening.

Although the majority of Americans now understand that most scientists think global warming is happening, fewer understand just how strong the level of consensus among scientists is. Only one in five Americans (20%) understand that nearly all climate scientists (more than 90%) are convinced that human-caused global warming is happening.

A larger percentage of Americans (25%) say they “don’t know” what percentage of climate scientists think human-caused global warming is happening.Respondents were asked to estimate the percentage of climate scientists who have concluded that human-caused global warming is happening by moving a slider bar which appeared on the screen of their computer. This slider allowed respondents to move the marker from 0% on the left to 100% on the right, or to any whole number between the two. A “don’t know” response option appeared below the slider bar.

Public misunderstanding of the scientific consensus – which has been found in each of our surveys since 2008 – has significant consequences. Other research has identified public understanding of the scientific consensus as an important “gateway belief” that influences other important beliefs (i.e., that global warming is happening, human-caused, and worrisome) and support for action.For more information, see van der Linden, S. L., Leiserowitz, A. A., Feinberg, G. D., & Maibach, E. W. (2015). The scientific consensus on climate change as a gateway belief: Experimental evidence. PLoS ONE, 10(2). https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0118489