Below is a slightly expanded version of the column that will run in Monday's Health and Science section of the Philadelphia Inquirer:
Several of the regular readers of this column have told me that since I've been brave enough to tell the truth about evolution, I should do the same for climate change and expose it as a hoax. In one case I replied that in my stories I always strive to reflect the truth to the best of my abilities. He wrote that he was "disappointed." These evolution-accepting climate change "skeptics" are an interesting breed, revealing some key differences in the ways they and creationists approach science.
Self-described climate skeptics are much more scattered in their views than are creationists, but they are better organized and together speak with a louder, and angrier voice.
There are some similarities between the two, as Steven Newton of the National Center for Science Education pointed out in an opinion piece for Earth Magazine titled Defending Science: the link between creationism and climate change. "It's phenomenal," Newton said in an interview. "They use the same tactics and same misunderstandings of the way science works." Both sometimes assume scientists are in a conspiracy to hide the truth. And both groups tend to see themselves as pioneers, he said, often invoking Galileo or the long-doubted theory of continental drift as examples of minority views eventually prevailing.
In my experience, those similarities are strongest among the most extreme biblical creationists and global warming conspiracy theorists. But one key difference across the board is that creationists by definition reject scientific thinking in favor of supernatural explanations. Whether they are biblical literalists or subscribers to "intelligent design," they find places to insert God into the natural world.
There is no equivalent supernatural force invoked by global warming skeptics/deniers. And while creationists are united in disbelieving that natural processes alone could produce humanity, climate deniers are disjointed in their targets. Some doubt the planet is warming, others disbelieve that human-generated CO2 plays a significant role, and still others accept both those premises but argue that curbing emissions will cause more harm than good.
There is some very basic science connecting CO2 to climate — science that some "skeptics" reject, others accept, and still others are unaware of. The idea goes back to the 1800s, when scientists realized that the earth was much warmer that it should be given the amount of energy it receives 93 million miles from the sun.
Nineteenth century chemists knew that the Earth absorbs sunlight and radiates infrared. With laboratory experiments they showed that carbon dioxide and water vapor absorb infrared, while oxygen and nitrogen let it pass through and escape. They realized that without our CO2, the Earth would freeze into a big snowball. Today, there are detailed explanations for the way greenhouse gases absorb infrared, then emit some upwards and some back down. College-level science students can work out the calculations showing how CO2 ultimately raises the atmosphere's temperature.
It's also well-established that human activity has dramatically increased the amount of CO2 in our planet's atmosphere. That alone seems like sufficient reason for concern. Climatologists have added additional lines of evidence connecting the rise to climate change — climate models, melting of the Arctic ice sheet and sea ice, and studies that use tree rings, ice cores and other proxies to estimate past climates and show the 20th century was unusually warm. Scientists now also have actual world-wide measurements of temperature and CO2 levels going back over a century. Those overlap and supplement information from ice cores.
There is uncertainty in exactly how increasing CO2 will play out in the future. Some climatologists say we may nudge the atmosphere past some tipping point after which the climate will swing wildly around in a way that humanity hasn't experienced for 10,000 years.
Worrisome as that sounds, some climate "skeptics" see any uncertainty as a reason not to act. Maybe, they say, it won't be that bad. Maybe curbing emissions will cause worse trouble. That view is not science denial. Those are value judgments and opinions on policy that have no equivalent among creationists.
The other major difference between creationists and climate change critics is public behavior. My columns get relatively few reactions from creationists and of those, most are reasonably polite. Climate change stories bring on a torrent of vehement, toxic email, which has become much bolder and more self-assured in the last three years.
These email barrages are deceptive barometers of public sentiment, said Stanford psychologist and political scientist Jon Krosnick. He found that when polled with straightforward questions, about three quarters of Americans have said they believe the globe has been getting warmer and even more say that if warming has been occurring, human activity is partly to blame. Only about 10 percent were confidently skeptical, but they can sound very loud.
Recently, he said, the skeptics have been rallied by people such as such as Mark Morano, who runs a blog called ClimateDepot, though he apparently has no science background. A New York Times profile said he'd been a reporter for the Rush Limbaugh show and a spokesman for Senator James M. Inhofe of Oklahoma, the ranking Republican on the Environment and Public Works Committee.
Krosnick sees evidence of the climate skeptics' organization in the fallout from a New York Times op-ed he wrote in 2010. In it, he explained why he thought his polls disagreed with others that purported to show that a majority of Americans doubted climate change. His questions were simple and straightforward, he wrote. Other polls used complicated, multi-part questions that would have been interpreted differently.
As a result, he got an influx of hate mail, including death threats, he said. He saw that as an opportunity to study political activism. He found the level of emotion "fascinating."
What's driving it? Normally, Krosnick said, three major motivating factors get people politically involved — self-interest, values and social identification. I could see how that applied to creationists, since there's a religious motivation that could create a powerful sense of identity, and possibly self-interest for those who think loyalty to the Bible will affect their experience in the afterlife.
Climate skeptics may get some sense of identity from their views, but Krosnick believes another factor may come to the fore — ego. "Some people may think that if 80 per cent of other people believe something, it must be wrong," he said. "It may create a sense of self-esteem for them to think they're smarter than most other people."
Krosnick re-examined a University of Texas survey whose authors claimed to show that the more people knew about climate change, the less they cared about it. "The implication was that if people were fully informed, nobody would care," he said.
What he found was that among Democrats and independents, those who were more informed who were most concerned. Among Republicans, being more informed on climate change made no difference in level of concern. But the "skeptics" will surely find grounds to deny that.
Additional notes: For a much more complete treatment of the physics behind greenhouse gases, see Paul S. Braterman's excellent book, "From Stars to Stalagmites: How Everything Connects." If you're looking for an in-depth but concise treatment of the science of climate change, his chapter on that topic is perfect. It also offers a list of all the common "skeptic" arguments and a tidy scientific rebuttal.
For a well-documented treatment of the political operatives and big money interests fueling the climate skeptics' movement, see "Merchants of Doubt" by Naomi Oreskes and Erik Conway.
For an insider's perspective on the science and politics of climate change, try "The Hockey Stick and the Climate Wars: Dispatches From the Front Lines" Michael Mann. It will remind biologists who have ever felt annoyed or beleaguered by creationists that things could be worse. Sure, you may be accused of offending God, but Mann has offended people who are richer than God.
Contact Faye Flam at 215-854-4977, firstname.lastname@example.org, or @fayeflam on Twitter. Read her blog at philly.com/evolution.