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In addition to divisions at Copenhagen between rich and poor countries, climate activists had to contend with some depressing poll results. Four new polls showed declining support for the belief that global warming is real.

The first was a survey taken in late September and early October by the highly respected Pew Research Center. Pew found a significant decline, from 71% in 2008 to 57% in 2009, in the proportion who believe there is solid evidence that global temperatures are rising. Another question in the poll showed that fewer people in 2009 saw global warming as a very serious problem than did in 2008--35% vs. 44%.

Next came a poll from ABC News and the Washington Post conducted in early November, before the so-called climategate scandal broke. In this poll, the number saying that global warming was probably happening declined to its lowest point since 1997, when they first asked the question. Like Pew, the ABC/Post pollsters found the number demanding action lower than it was last summer.

Also in early November, Harris Interactive surveyed adults online and found that 51% believed the "theory that increased carbon dioxide and other gases released into the atmosphere will, if unchecked, lead to global warming and an increase in average temperatures." That's the lowest rating since Harris began asking it 12 years ago.

In a fourth poll, conducted in early December by CBS News and the New York Times, 37% said global warming was a very serious problem and should be one of the highest priorities for government leaders. In 2007, 52% gave that response.

What's going on? All four pollsters point to our polarized politics as part of the explanation. Most of the movement in the polls has come from Republicans and conservatives who may have changed their minds about the issue or are simply using it to express dissatisfaction with President Obama. In the Pew poll, 75% of Democrats vs. only 35% of Republicans saw solid evidence of global warming. In the ABC/Post poll, the belief that warming is occurring fell by 20 points among Republicans between 2008 and 2009 while holding steady among Democrats. In the Harris poll, 73% of Democrats but only 28% of Republicans believed greenhouse emissions cause global warming. And, in the CBS/NYT poll, 22% of Republicans, compared with 52% of Democrats, called the issue a very serious problem requiring a high-priority response.

Interestingly, two surveys by Ohio State University taken before and after the heated Kyoto meetings in 1997 showed increased polarization. There was an 8-point gap between Democrats and Republicans before Kyoto and a 22-point gap after the conference.

But there are other possible explanations. Right now Americans are deeply concerned about the economy. I've always thought that the trade-off between protecting the environment and jobs was a phony one; people want both, but at certain times, their preference for one is greater than the other. Today, the economy is the No. 1 priority. In the new CBS/NYT poll, 61% (up from 36% in 2007) said stimulating the economy was more important now; 29% (down from 52%) said protecting the environment was.

Additionally, it shouldn't be surprising that opinion moves around a lot on issues where public opinion is mushy, as it is on many complex issues. In an October Pew poll, only 23% knew that the term "cap and trade" was associated with climate change.

Finally, people may simply be tired of hearing about the coming climate apocalypse. Only 28% in the new Harris poll knew that the subject of a major international conference in Copenhagen was climate change, demonstrating that although they've been bombarded with information by a sympathetic press, people just aren’t paying attention. In addition, media credibility is very low these days, and many Americans may simply be discounting what they read about climate change, especially after the recent climategate scandal. All in all, bad news for the activists.

Karlyn Bowman is a senior fellow at AEI.