Crossposted with TheGreenGrok.com, the blog by the dean of Duke's Nicholas School
Scientific mistakes of mythic proportions.
For the record, it should be noted that Fox News is not my primary outlet for keeping abreast of the news. So normally I wouldn't have seen this August 6 "Fox and Friends" piece on global warming (sorry -- you'll have to view a commercial to see it). But the media watchdog group Media Matters for America contacted me for my comments on it. So I figured I'd watch and what I saw compelled my comments here.
Out of the Gate: Fox Takes on Climate
Fox News called the three-and-a-half-minute segment "Climate Change Myths: Separating Fact From Fiction" -- an apt name because as far as the science is concerned, there's very little that could be characterized as fact, and a whole lot that could pass for fiction.
The segment was pegged to what the morning hosts called a new NASA study which, in their words, "seems to debunk whether [global warming] is actually manmade." Since that paper [pdf] (by Roy Spencer and William Braswell) has been pretty thoroughly debunked in places like RealClimate and ClimateProgress, I will focus on the rest of the segment.
Next up was a Rasmussen poll finding that 69 percent of Americans believe scientists have lied to support their theories about global warming. Viewers, I suspect, are intended to receive this result as an indictment of global warming science. But hold on a minute. Suppose you're convinced that global warming is "manmade" and that
skeptics are cooking the books to advance their viewpoint, would you not
answer yes to that question? And so I'm not at all sure what this poll means.
Meteorologist Bastardi Takes Center Stage
Following the brief poll discussion the really good stuff begins. For the "real story" and "the facts" the morning hosts bring on meteorologist Joe Bastardi, the chief forecaster of the consulting firm WeatherBell.
After a quick recap of the recent record-breaking hot weather and why it's not a sign of global warming (with Bastardi making note of what he claims was the "far worse climate" of the '30s-'50s), the meteorologist makes his case for "Why CO2 Can't Cause Warming."
Bastardizing the First Law
Bastardi advances arguments by beginning with basic science and then tortuously applying it to support his own unscientific point of view.
For one example, he argues that:
Carbon dioxide (CO2) can't warm the atmosphere because it would violate the first law of thermodynamics.
Wow. The first law of thermodynamics -- that's heavy stuff. Far be it from me or any other self-respecting scientist to go against this law, arguably the most basic in all of physics, which says that energy can neither be created nor destroyed.
Bastardi correctly points out that this law (also known as the conservation of energy) requires that if the atmosphere is heating up, there must be an external source of energy. So far, we're on the same page. But then he slips up, arguing that CO2 cannot cause warming because it is not a source of heat.
Can this man really have that poor an understanding of atmospheric physics or is something else at play? You be the judge.
Of course CO2 is not the "source of heat." The heat source is the Sun. CO2 causes the warming by trapping more of the Sun's energy in the atmosphere, causing the temperature to rise.
Consider this analogy. It's a cold night (hard to imagine with this summer) and you're chilly so you add a blanket to warm up. The blanket doesn't create heat; it's not the source of energy. It merely acts as an insulator, trapping your body's heat. CO2, via the greenhouse effect, does a similar thing.
Reversing a Hundred or So Years of Science
Realize that Bastardi's essentially arguing that the greenhouse effect does not exist. This effect is something we have known about for more than 100 years, the basic physics of which were worked out by some of the 19th century's greatest scientists, such as Fourier, Tyndall, and Arrhenius. Without the greenhouse effect, simple thermodynamics, including the first law, predict that the Earth's temperature would be at or below the freezing point of water. Without the greenhouse effect, we could not explain the high temperatures of Venus.
You gotta hand it to the guy -- trashing the work of Arrhenius and Fourier takes chutzpah, not much smarts but lots of chutzpah.
An Unprincipled Application of a Principle
Next up is a discussion of Le Chatelier's principle which begins with an embarrassing exchange that makes clear that nobody on the show bothered to research the pronunciation of the French chemist's name -- including, it would appear, Bastardi.
Le Chatlier's principle states that a system at equilibrium that is disturbed or pushed from that equilibrium will oppose the change and act to restore the equilibrium.
So, Bastardi argues, the atmosphere will inevitably return to its pre-global-warming temperature -- he in fact boldly predicts that on the basis of this principle, global warming has already ceased and temperatures will shortly return to the temperatures of the 1970s. Why the temperatures of the 1970s and not the Ice Age temperatures or the extremely warm temperatures of the Eocene? Alas, he does not say.
Folks, this is total nonsense.
Le Chatlier's principle applies to an isolated system at equilibrium. If perturbed, that system will tend to oppose the perturbation, and if left alone, it will tend to return to its original state. It does not say that the system will actually return to its original state, and if continuously perturbed, the system clearly will not. The principle also does not rule out the possibility of the system moving to a completely different state if the perturbation is large enough.
Looking at Le Chatelier's Principle Through a Rubber Band
Let's consider another analogy -- in this case a rubber band. Apply an outward force on a rubber band (i.e., stretch it), and its shape will change. Let go of that stretched band, and it will relax more or less to its original shape. A nice application of the principle. But now imagine that you don't let go of the band but continue to stretch it. It will contract against your fingers, trying to get back to its original shape but it will not actually contract.
In the case of global warming, we are continuously adding more CO2 to the atmosphere, effectively stretching and stretching that climate rubber band. Under those conditions, Le Chatelier's principle does not predict that the atmosphere will return to temperatures before the warming occurred. Now, if we suddenly stopped emitting CO2, the atmosphere would slowly (as it turns out, extremely slowly -- see here and here ) relax back to cooler temperatures. But that's a big if and not exactly the context for Bastardi's comments.
Snap
And there's another important aspect of this. If you keep on stretching that rubber band, it will eventually break. And if that happens, the rubber band will never return to its original shape.
Could the same snap happen to the climate if we keep adding CO2? Probably. When will it snap? We're not sure; we'll have to wait and see. But there's one loud snap that has already been heard: Joe Bastardi has stretched his scientific credibility beyond the breaking point.
Correction: August 12.
This post was corrected to clarify that it was Fox News who characterized Roy Spencer's study as a NASA study.