Americans More Skeptical of Global Warming

The number of Americans who believe there is solid evidence of global warming has declined from 71 percent in 2008 to 57 percent, and those that see global warming as a very serious problem dropped from 44 percent to 35 percent in the same time period, according to a Pew Research Center survey conducted Sept. 30-Oct. 4.

A smaller number than previously measured attribute global warming to human activity. Forty-seven percent cited human activity in 2008 compared to 36 percent now.

Along partisan lines, Democrats who believe there is solid evidence for climate change dropped from 83 percent to 75 percent, independents from 75 percent to 53 percent and Republicans from 49 percent to 35 percent.

However, the public still supports putting limits on carbon emissions through a "cap and trade," which would allow companies that exceed emission allowances to buy credits from lower-polluting companies. Fifty percent favor such a policy compared to 39 percent who oppose it, with 11 percent undecided.