An Angus Reid poll released in late June 2012 shows that 58% of Canadians believe “it is more important to protect the environment, even at the risk of hampering economic growth”. Only 45% of Americans and 43% of Britons agreed with that statement. The summary is at: http://www.angus-reid.com/polls/45431/global-warming-skepticism-higher-in-u-s-and-britain-than-canada/ with a link to the full report and tables.
In the U.S., a survey conducted by the University of Michigan compares the levels of concern for climate change among adults between 32 and 52 years of age. Only 16% were very or moderately interested in the issue (down from 22% in 2009). The detailed report, including where the cohort sources their information, and possible explanations for the lack of engagement is: Miller, Jon D. “Climate Change: Generation X Attitudes, Interest, and Understanding” in Generation X Report v. 1 #3 (Summer 2012) at: http://www.sampler.isr.umich.edu/wp-content/uploads/2012/07/GenXReport.pdf