April 12, 2013

Americans Who Believe in Global Warming Blame Human Activity more than Natural Patterns

42%

Roughly four-in-ten Americans who believe there is solid evidence of global warming say the cause is human activity, not natural weather patterns.

About seven-in-ten (69%) of Americans say there is solid evidence that the earth’s average temperature has been getting warmer over the past few decades, according to our survey conducted in March.

Among those who see evidence of global warming, more say it is caused mostly by human activity (42% of the public) than by natural patterns in the earth’s environment (23%). Nearly three-in-ten Americans (27%) say there is no solid evidence of warming.

These opinions are little changed from last fall. But four years ago, just 57% saw solid evidence of global warming and 36% said it was mostly caused by human activity.

There has been a sizable partisan gap in views about whether there is solid evidence of global warming since the Pew Research Center began asking this question in 2006. In the March survey, almost twice as many Democrats (87%) as Republicans (44%) say there is solid evidence that the average temperature on earth has been rising.

Further, Democrats are three times as likely as Republicans to say that human activity is mostly causing global warming (57% vs. 19%). However, there are differences within each political grouping on this question. Moderate and liberal Republicans are more likely to say it is mostly happening because of human activity (27% vs. 16%). Far more liberal Democrats (72%) than conservative and moderate Democrats (51%) say the earth is getting warmer mostly because of human activity. Read more