"While a majority of Canadians say that climate change is a fact and is caused by emissions, only two-in-five Americans and Britons concur," according to a June 27, 2012, press release from Angus Reid Public Opinion. Respondents were asked, "Which of the following statements comes closest to your view of global warming (or climate change)?" "Global warming is a fact and is mostly caused by emissions from vehicles and industrial facilities" was preferred by 58% of Canadians, 42% of Americans, and 43% of Britons; "global warming is a fact and is mostly caused by natural changes" was preferred by 20% of Canadians, 21% of Americans, and 27% of Britons; "global warming is a theory that has not yet been proven" was preferred by 14% of Canadians, 21% of Americans, and 21% of Britons; and 8% of Canadians, 16% of Americans, and 9% of Britons were not sure.
The full report from Angus Reid also includes (PDF) data showing the variance among different regions in all three countries — acceptance of global warming as caused by emissions was strongest in the Atlantic provinces of Canada (75%) and Quebec (71%), the American West (48%), and London and Scotland (48% and 47%) — and from five previous polls using the same questions conducted from 2009 to 2011. The latest poll was conducted among 1017 American adults, 2026 British adults, and 1004 Canadian adults in May and June 2012; Angus Reid explains, "The margin of error — which measures sampling variability — is +/-2.2% for Great Britain and +/-3.1% for the United States and Canada. The results have been statistically weighted according to the most current education, age, gender and region Census data to ensure a sample representative of the entire adult population of each country."