2010-10-15 09:20:10Americans’ Knowledge of Climate Change
John Cook


Americans’ Knowledge of Climate Change reports results from a national study of what Americans understand about how the climate system works, and the causes, impacts, and potential solutions to global warming. Among other findings, the study identifies a number of important gaps in public knowledge and common misconceptions about climate change.

Overall, we found that 63 percent of Americans believe that global warming is happening, but many do not understand why. In this assessment, only 8 percent of Americans have knowledge equivalent to an A or B, 40 percent would receive a C or D, and 52 percent would get an F. The study also found important gaps in knowledge and common misconceptions about climate change and the earth system. These misconceptions lead some people to doubt that global warming is happening or that human activities are a major contributor, to misunderstand the causes and therefore the solutions, and to be unaware of the risks. Thus many Americans lack some of the knowledge needed for informed decision-making in a democratic society. For example, only: 

  • 57% know that the greenhouse effect refers to gases in the atmosphere that trap heat;
  • 50% of Americans understand that global warming is caused mostly by human activities;
  • 45% understand that carbon dioxide traps heat from the Earth’s surface;
  • 25% have ever heard of coral bleaching or ocean acidification.
In addition, despite the recent controversies over “climategate” and the 2007 IPCC report, this study finds that Americans trust scientists and scientific organizations far more than any other source of information about global warming.


2010-10-15 10:47:10

Yes, that's why the main skeptics' argument is not "Scientists are wrong," but rather "Scientists disagree."
2010-10-16 05:28:35


Hah, you beat me to it; here I am w/the URL for the PDF in my clipboard, too late. 

Direct to PDF of report:


For Skeptical Science authors this is a must-read because it's full of cues about where we can best devote our time and energy.

First instincts on being confronted with John Q. Public's limitations might be derision or despair, but there's nothing useful in those reactions. Instead, this is a map identifying holes needing to be plugged. 

Also worth noting that the authors are well-respected in their domain, which is not that of opinion pollsters; we can have reasonable confidence in these findings because Leiserowitz's methods are sitting on a sizable and solid pyramid of research into controlled elicitation, cognition, mental models. 

2010-10-16 05:58:36some findings
Dana Nuccitelli

Among some of the findings, only 63% said that global warming is even happening (and among those, only 56% were very or extremely sure). Only 50% stated that humans are the main cause of the current warming (though this is actually higher than I expected). Only 39% said that most scientists think global warming is happening (this is an appalling result). Only 57% correctly identified what the greenhouse effect is in a multiple choice question (most who got it wrong thought it referred to the ozone layer).

I think the most critical finding is probably that only 39% said that most scientists think global warming is happening.  It's great that ~75% trust climate scientists, the problem is that they don't know what climate scientists think!

Not understanding what the greenhouse effect is or that the planet is warming is a bit of a problem, but as long as most people still trust climate scientists, it's not a terribly big deal.  We defer to the experts on most issues we don't understand.  So the problem is in communicating the consensus to the public.  Apparently deniers have been successful in convincing the public there's widespread debate, probably mainly because they're able to get equal time in the media.  I'm not sure how you combat that.

2010-10-16 08:22:52
Rob Painting

Ouch!. I'm sure that the results would scarcely be any different in most western cultures though.


IMO the media is THE number one culprit in this "travesty". I don't know about your media, but almost all forms of media here in NZ are getting continually dumbed down and more akin to a source of gossip, than actual information. Which is why I hardly ever watch television news (except for sports of course!) or read newspapers - it makes me want to pull my hair out, and I don't have any!. 

2010-10-16 10:09:10media
Dana Nuccitelli

In the USA, there are 2 problems with the media.  Number 1, they feel that in order to be "balanced" they have to present "both sides".  So if they interview a climate scientist, they'll also generally interview a 'skeptic' like one of the Pielkes or freaking Monckton or someone similar.  This allows the ~2% of skeptics to get nearly 50% of the media attention and explains the massive confusion over what scientists think about global warming.  No question it's the fault of the media.

The other problem is that our media has stopped evaluating the accuracy of their sources and now just report what the interviewee states.  They've basically become stenographers.  So media reports end up being "Gavin Scmidt says CO2 is causing global warming but Lord Monckton says it's the Sun", and the reader has no way of telling which side is right without doing further research, which ain't gonna happen.  So again the reader is left thinking that there's a big scientific debate about global warming.

Reporters are also exceptionally careful not to interject their own opinions, to a fault.  For example, instead of saying "the Earth is warming" they'll say "some scientists believe the Earth is warming".  That way they don't actually have to do any research or know anything about what they're reporting on, and if they're wrong, they can just blame their sources.  Many American media outlets no longer employ science journalists.

2010-10-24 08:46:40
Andy S


I'm always inclined to assume that people's beliefs depend on their level of knowledge. But there was a recent Pew Forum Survey on religious knowledge that showed, among other things, that less than half of Americans could name the authors of the four gospels. Protestants did better than Catholics but atheists did best of all. I wonder what the results would be if a survey were to enquire how much people expected sea level to rise over the next few decades? I wouldn't be surprised if the average skeptic did better (ie closer to the IPCC estimate) than the average person who accepts AGW but who only vaguely remembers scenes of flooding from watching An Inconvenient Truth. That's hypothetical, of course, I'm just guessing and I would rather be wrong.

Parallels are often drawn between the public's attitude towards AGW and tobacco. However some studies (the results from others are mixed) show that non-smokers and smokers alike exaggerate the risks of smoking. What do you think the chance of a 55 year old who has smoked two packs a day for most of his life getting cancer in the next ten years? Find out the answer using this calculator.

It is often argued (and I think it's true) that there was a deliberate disinformation campaign to sow confusion among the public about the science behind smoking and that the same thing is happening now with climate change denial. The anti-tobacco lobby eventually won their war but perhaps a case could be made that they won only by exaggerating the perceived risks. Perhaps that was necessary--and all to the good--but the fight wasn't won by making sure people grasped the statistics accurately. Nobody nowadays is going to write a newspaper article entitled Smoking: nowhere near as dangerous as most people think.

My own views on climate change morphed from lukewarm to alarm by reading the scientific literature. I don't think many people will follow that path and I'm unsure how much difference improving the scientific knowledge of the public can make. That's the only tool in my toolbox, however. Let's just hope that working away at the myth that there's a real debate going on amongst scientists will suffice.


2010-10-24 09:38:07



- I believe atheists and Jews are pretty high in Christian religious knowledge because they always have to defend their positions in this arena against a cultural norm. That is, unfortunately, NOT true of skeptics. A better analogy would be to an SkS-er stuck in Oklahoma. 

- I think the big turning point on tobacco was when a temporary worker at Brown & Williamson, a major tobacco company, was tasked with making photocopies of confidential internal memos. He read through them, and realized that their scientists knew perfectly well what the risks of cancer and other health problems would be, due to smoking; knew that tobacco is addictive, due to nicotine; knew that the arguments they were using in public were wrong or, at best, irrelevant. He leaked the papers to UCSF that published them. Whatever credibility the tobacco companies still had up 'til then was blown. You can read more about it here.

2010-10-25 11:12:02
Andy S



 I certainly didn't mean to open a debate here on religion or on the history of the tobacco misinformation wars. The Basic Version (copyright J Cook) of my post is that knowledge and belief aren't always correlated and that we might  be kidding ourselves that more education might be sufficient to change minds. I guess I was just in a pessimistic frame of mind when I wrote it.