As one of the world's largest polluters and, until lately, not really concerned about global warming, a new study shows that a growing number of Americans consider global warming an important threat that calls for drastic action. In fact 40% say that a presidential candidate's position on the issue will strongly influence how they vote, according to a national survey conducted by Yale University, Gallup and the ClearVision Institute. 

"One of the most surprising findings was the growing sense of urgency," says Anthony Leiserowitz, director of the Yale Project on Climate Change and the study's principal investigator. "Nearly half of Americans now believe that global warming is either already having dangerous impacts on people around the world or will in the next 10 years-a 20-percentage-point increase since 2004. These results indicate a sea change in public opinion."
The survey's findings include:
* Sixty-two percent of respondents believe that life on earth will continue without major disruptions only if society takes immediate and drastic action to reduce global warming;
* Sixty-eight percent of Americans support a new international treaty requiring the US to cut its emissions of carbon dioxide 90% by the year 2050. Yet, Leiserowitz notes, the US has yet to sign the Kyoto Protocol, an international treaty that would require the US to cut its emissions 7% by the year 2012;
* A surprising 40% of respondents say a presidential candidate's position on global warming will be either extremely important (16%) or very important (24%) when casting their ballots. "With the presidential primaries and general election near," Leiserowitz says, "candidates should recognize that global warming has become an important issue for the electorate."
* Eight-five percent of those polled support requiring automakers to increase the fuel efficiency of cars, trucks and SUVs to 35 miles per gallon, even if it meant a new car would cost up to $500 more; and 82% support  requiring electric utilities to produce at least 20% of their electricity from renewable energy sources, even if it cost the average household an extra $100 a year;
* Majorities of Americans, however, continue to oppose carbon taxes as a way to address global warming – either in the form of gasoline (67% against) or electricity taxes (71% against); and
* Finally, 50% of respondents say they are personally worried -15% say a "great deal"- about global warming. "Many Americans, however, believe that global warming is a very serious threat to other species, people and places far away," says Leiserowitz, "but not so serious of a threat to themselves, their own families or local communities. Nonetheless, they do strongly support a number of national and international policies to address this problem."