A new survey from the Energy Policy Institute at the University of Chicago and the Associated Press-NORC Center for Public Affairs Research examines American attitudes toward climate change. Asked "Do you think climate change is happening, do you think climate change is not happening, or aren't you sure?" 72% of respondents thought that climate change is happening, while 9% thought that it is not happening, 19% were unsure, and 1% skipped or refused to answer. A press release added the detail that "85 percent of Democrats and 61 percent of Republicans" thought that climate change is happening.
Respondents who thought that climate change is happening were then asked, "Do you think climate change is caused entirely by human activities, caused mostly by human activities, caused about equally by human activities and natural changes in the environment, caused mostly by natural changes in the environment, or caused entirely by natural changes in the environment?": 15% of respondents said entirely by human activities and 40% said mostly by human activities, while 32% said equally by human activities and natural changes, 11% said mostly by natural changes, and 2% said entirely by natural changes.
According to the topline report of the survey (PDF), "Interviews for this survey were conducted between August 17 and 21, 2017, with adults age 18 and over representing the 50 states and the District of Columbia. Panel members were randomly drawn ... and 1,038 completed the survey — 861 via the web and 177 via telephone. Interviews were conducted in English. ... The overall margin of sampling error is +/- 4.1 percentage points at the 95 percent confidence level, including the design effect. The margin of sampling error may be higher for subgroups."