What’s driving opinion on global warming?

Two weeks ago Andrew Revkin of the New York Times wrote an article with the headline, "In Climate Debate, Exaggeration is Common Pitfall." In it he pointed to Washington Post columnist, George Will, on the right, who claimed global warming is not happening by drawing unscientific conclusions from sea ice data, and to Al Gore, on the left, for claiming that increased hurricane damage is due to global warming. There is not scientific evidence for either claim, Revkin noted.

Revkin quoted American University communications professor, Matthew Nisbet, who studies the social science of global warming communications. Nisbet said:

Mr. Gore's approach, focusing on language of crisis and catastrophe, could actually be serving the other side in the fight.

"There is little evidence to suggest that it is effective at building broad-based support for policy action," Dr. Nisbet said. "Perhaps worse, his message is very easily countered by people such as Will as global-warming alarmism, shifting the focus back to their preferred emphasis on scientific uncertainty and dueling expert views."

The article inspired Media Matters and Center for American Progress to level harsh attacks on Revkin, claiming that while Will's statements were gross lies, Gore's statements were mere exaggerations.

But now there is new empirical evidence to support Revkin's claim that hyping the threat of global warming is actually hurting public support for action.

A new survey from Gallup shows that the percentage of Americans who say that the seriousness of global warming is being exaggerated went from 30 in 2006 to 41 percent in 2009. The percentage of those who say news of global warming is exaggerated went from 51 to 66 for Republicans, 29 to 44 percent of Independents, and 15 to 22 percent among Democrats between 2006 and 2009.

This coincides with a period of intensified media coverage of "An Inconvenient Truth," released in June 2006, which suggested that global warming was behind recent hurricanes, droughts, and floods. The poster for "An Inconvenient Truth" showed a hurricane coming out of a smokestack. The problem, as Revkin points out, is that scientists cannot and do not attribute the increase in these events to global warming.

The new Gallup polling indicates that, in exaggerating global warming's effects since 2006, greens have actually created their own backlash.

Climate progress blogger Joe Romm claims that the poll findings "must be due to the messaging and the media and the misinformers." But Romm offers no evidence for such a claim. I suspect climate skeptics have done less, not more, over the last year. Their conference sponsored by the Heartland Institute that Revkin reported on today was a dud.

The more likely explanation is the most obvious one: voters believe that global warming is being exaggerated because it is being exaggerated. Greens like Gore and Romm routinely attribute things to global warming that cannot yet be attributed to global warming scientifically.

As we wrote in Break Through, global warming is a very serious, even existential threat. But exaggerated, apocalyptic, and unscientific claims make political action to deal with it harder, not easier. Apocalypse talk is great red meat for the green base, but as Gallup shows, it is backfiring even among Democrats.