A Reuters/Ipsos poll conducted September 8-12 found that 83 percent of Americans believe the Earth has been warming, up from 75 percent last year. About 71 percent of the Americans who believe warming is happening think that it is caused partly or mostly by humans.
These findings appear contradictory to a number of recent surveys. In a March Gallup poll, only 50 percent attributed global warming to human causes. In a June Rasmussen poll, the figure was 40 percent.
In another Gallup survey over 43 percent of Americans claimed the seriousness of the global warming issue has been generally exaggerated.
The September Reuters poll does suggest, however, that climate skeptics are digging in their heels. In 2010 the certainty of skeptics was 35 percent, while in 2011 it was 53 percent, the poll found.
Most of the Republican candidates have expressed doubts about whether global warming is man-made, with Rick Perry saying that a “substantial number” of scientists have manipulated climate data, and Michele Bachmann calling climate change a hoax. But this may have actually pushed acceptance, as Americans watching the debate are forced to think about their stance on the issue, according to Stanford University political science professor and Resources for the Future fellow Jon Krosnick, interviewed by Reuters.
He said voters were also likely influenced by reports this year that 2010 tied for first place as the warmest year since the 1880s.
The Reuters poll found that a majority of Americans from both political parties agree that global warming is happening. About 72 percent of Republicans believe it is real, compared to 92 percent of Democrats. And it could be an important issue in the 2012 elections, because about 15 percent of voters see it as their primary concern, Krosnick said.
The Reuters/Ipsos poll of 1,134 adults, including 932 registered voters, had a margin of error of 3 percentage points for all respondents and 3.1 points for registered voters.
Picture credit: NASA Goddard Space Flight Center