"A record 60% of Americans now think that global warming is happening and that humans are at least partially responsible for the rising temperature," according (PDF) to the latest survey from the National Studies on Energy and the Environment conducted by the University of Michigan and Muhlenberg College.
Asked "From what you've read and heard. Is there solid evidence that the average temperature on earth has been getting warmer over the past four decades?" 73% of respondents — the highest rate since the survey asked the question in 2008 — said yes, 15% said no, and 12% volunteered that they were unsure.
Asked about the causes of climate change, 34% of respondents attributed it to human activity, 26% attributed it to a combination of human activity and natural patterns or were not sure, 12% attributed to natural patterns, while 12% were not sure if climate is changing and 15% thought that climate is not changing.
According to the NSEE report, there were 751 adult respondents for the survey, contacted via land line and cell phones between April 29 and May 25, 2018; the margin of error was +/- 4% at a 95% level of confidence. The data were weighted by gender, age, race, income, and education to reflect the population characteristics of the United States.