Just a slim majority of Americans consider global warming "a very serious problem," despite an avalanche of publicity on the issue, and many aren't even taking the "green" actions they support, a nationwide survey suggested today.

"Clearly, there's a lot left to do in raising awareness," says Edward Maibach, senior author of the survey, who heads a center on climate change and communication at George Mason University.

The poll of more than 11,000 Americans, thought to be the largest ever done on climate change, reveals a gulf between public perceptions and the scientific consensus that the phenomenon poses threats. In the survey, 62 percent considered global warming a serious danger. Those who are doing the most to reduce their own "carbon footprint" see the problem and also believe their actions can make a difference.

There is growing concern among behavior experts that "there has been too much fear-mongering and not enough emphasis on what people can do," Maibach says.

The survey was commissioned by Porter Novelli, a marketing and communication firm.

Americans endorse more "green" actions — steps such as buying fuel-efficient cars, using less energy at home, recycling — than they're doing, Maibach says.

And there's a huge partisan divide: Democrats are about three times more likely than Republicans to see high danger in global warming and think they can do something about it. But Democrats are living only slightly more green than Republicans.

An unusual step in the poll was including about 1,000 children of the adults surveyed. The children, in grades four to 12, were more likely to see global warming as a threat but also more optimistic than adults that technology can solve it.

Homes where kids and adults agree that there's a problem, and people can curb it, were taking the most steps to reduce greenhouse gases, Maibach says. It's not clear who's influencing whom, he adds.

Children often nudge parents to use less energy, says Katherine Shea, a pediatrician and adjunct public health professor at the University of North Carolina at Chapel Hill. "Kids just "get it,' " she says, "and they have the science on their side."

About three out of five adults agree "global warming is a threat to all life on the planet." The rest are in denial, says Camille Parmesan, a biologist at the University of Texas and an expert on the effects of climate change. "It's absolutely a threat. We don't see a region or a group of organisms that hasn't been affected."

A lack of action concerns Jack Williams, a geographer at the Center for Climatic Research at the University of Wisconsin-Madison. "There's strong scientific consensus that immediate action is needed because of the long life of greenhouse gases."

Concern about global warming has modestly increased in surveys he has done over the past decade, says Jon Krosnick, a Stanford University political scientist. But "they're more enthusiastic about government and businesses doing things than doing stuff themselves."

Join our discussion: Making green choices at your house?