The number of people who believe global warming is a problem is ticking back up, according to a set of recent polls.
This news comes as the Senate voted down a measure by Sen. Lisa Murkowski, Republican of Alaska, to block the Environmental Protection Agency from regulating greenhouse gases from power plants and other polluters under the Clean Air Act.
The rules will now go into effect in January, and some observers say is an indication of how energy legislation may tip.
As for the polls, one from the Woods Institute for the Environment at Stanford University found that three out of four Americans believe that the Earth is gradually warming from human activity and want the government to do something about it.
Funding came from the National Science Foundation, and results were based on telephone interviews conducted from June 1-7 with 1,000 randomly selected American adults.
"Several national surveys released during the last eight months have been interpreted as showing that fewer and fewer Americans believe that climate change is real, human-caused and threatening to people," Krosnick said. "But our new survey shows just the opposite."
About three quarters said the Earth's temperature probably had been heating up over the last 100 years, and 75 percent said that human behavior was substantially responsible for any warming that has occurred. The poll has been taken for the last four years and the decline in people who believe global warming has been happening is dropping, researchers said.
Skeptics who don't trust scientists often cite the weather -- 2008 was the coldest year since 2000 -- but researchers say year to year fluctuations are "uninformative." Other point to "climategate," where in late 2009 hacked emails from climate scientists at the University of East Anglia in Britain showed some appeared to be colluding to silence unconvinced colleagues. But trust in the scientists also appears to have remained high, with almost three-quarters trusting them, researchers said.
A second poll from Yale and George Mason universities showed public concern about global warming is again on the rise.
The number of people who believe global warming is happening has risen 4 points since January, to 61 percent. The number who believe that it's mostly caused by human activity rose by 3 points, to 50 percent.
The number who worry about global warming rose three points, to 53 percent. And the number of Americans who said that the issue is personally important to them rose five points, to 63 percent.
"The stabilization and slight rebound in public opinion is occurring amid signs the economy is starting to recover, along with consumer confidence, and as memories of unusual snowstorms and scientific scandals recede," said Anthony Leiserowitz, director of the Yale Project on Climate Change Communication, said in a statement.
"The BP oil disaster is also reminding the public of the dark side of dependence on fossil fuels, which may be increasing support for clean energy policies," he said.
The number of Americans who said President Obama and Congress should place a higher priority on developing sources of clean energy increased 11 points, to 71 percent.
There was also more public support for regulating carbon dioxide as a pollutant (77 percent, up by 6 since January); funding more research into renewable energy sources (87 percent, up by 2); offering tax rebates for people who buy fuel-efficient vehicles and solar panels (83 percent, up by 1); signing an international treaty that requires the United States to cut its emissions of carbon dioxide 90 percent by the year 2050 (65 percent, up by 4); requiring electric utilities to produce at least 20 percent of their electricity from renewable energy sources, even if it cost the average household an extra $100 per year (61 percent, up by 2); and expanding offshore drilling for oil and natural gas off the U.S. coast fell (62 percent, down by 5).
This poll surveyed 1,024 American adults. The margin of sampling error is plus or minus three percent. It was conducted from May 14, 2009 to June 1, 2010 by Knowledge Networks, using an online research panel of American adults.
NASA handout photo of the globe via AFP/Getty