Friday, February 26, 2010

The Not-so-Hidden Flaw in this Climate Argument

There are sometimes people think that I am a global warming denier (I'm not), but I am not entirely convinced that the dire predictions from the global warming camp are supported by the evidence. I am skeptical of conclusions based entirely on models, and I am really skeptical of anything where I perceive less-than-open information exchange combined with vested interests and a lot of money. Given all of that, I feel free to rip apart anyone's argument regardless of which side they happen to be on. :) That's how science works!

So I was pointed to an article called "The Hidden Flaw in Greenhouse Theory" which has such flawed logic itself that I am surprised someone wrote it.


To summarize the article, I quote the last paragraph:
An idea has been drummed into our heads for decades: that roughly 1% of the atmosphere's content is responsible for shifting the earth's surface temperature from inimical to benign. This conjecture has mistakenly focused on specifically light-absorbing gases, however, ignoring heat-absorbing gases altogether. Any heated atmospheric gas radiates infrared energy back toward the earth, meaning that the dreadful power we've attributed to light-absorbing molecules up to now has been wildly exaggerated and must be radically adjusted -- indeed, pared down perhaps a hundred times. Because all gases radiate the heat they acquire, trace-gas heating theory is an untenable concept, a long-held illusion we'd be wise to abandon.

How does he come to such a grand conclusion? He starts with a quote of a NASA elementary school guide, which has:

Question: Do all gases absorb heat?
• Answer: No. Only some gases have the unique property of being able to absorb heat.

Then he (correctly) criticizes this guide saying
So how does NASA go wrong? By consistently confusing light and heat, as you see in the illustration below, where infrared light is depicted as heat.

Clearly NASA should have said that greenhouse gases absorb infrared light, or radiation.

Then the author continues with this:
Why does NASA go wrong? Because it has a flimsy yet lucrative theory to foist on the taxpaying public, that's why. As the space agency explains in the Main Lesson Concept, the core idea of greenhouse theory is that downward radiation from greenhouse gases raises the earth's surface temperature higher than solar heating can.

This is amazing. Regardless of ones stance on global warming, the greenhouse effect (badly named) is a well known, well established consequence of the basic laws of thermodynamics. Without it, Earth would be far less habitable!

Conduction, Convection, Radiation, Oh My!

He continues:

To make this idea seem plausible, therefore, it's crucial to fix people's attention on the 1% of the atmosphere that can be heated by radiant transfer instead of the 99% and more that is heated by direct contact with the earth's surface and then by convection.

As a nitpick, it would actually be more like 5 percent or so, because water vapor is the most abundant greenhouse gas. Even so, his argument is fallacious, that a trace gas cannot cause significant warming. Let's take another example of a trace gas that increases atmospheric warming: ozone. In the stratosphere, at the "ozone layer", the concentration of ozone is about 2 to 8 parts per million. That is 0.0002%! Despite this trace amount, we get significant warming of the stratosphere as shown here.

His reasoning on this issue is
Consider too that since most air molecules are infrared-transparent, they can't be heated by the infrared that CO2 and water vapor emit. This means that downward radiation from "greenhouse gases" can only explain how the earth's surface might get warmer, not the rest of the atmosphere.

No one is suggesting that the non-greenhouse gases are being heated by the re-radiation of the greenhouse gasses. They are heated by the collisions with greenhouse gasses, thus raising the overall atmospheric temperature. This feedback loop continues until the new balance, with the surface, is established. It's strictly conservation of energy. Some is radiated, some is lost in collisions, and the gasses in the atmosphere as well as the surface adjust until an equilibrium temperature is reached. A simple process, really.

At the crux of his argument is this:

For meteorologists acknowledge that our atmosphere is principally heated by surface contact and convective circulation.

This is just wrong. What physicist do is follow the money, or the energy in this case. A very simple balance can be shown, quantified, and verified by numerous types of measurements. A very simple picture of it is here.


(From, which cites Houghton et al., (1996: 58), which using data from Kiehl and Trenberth (1996).)

As a fraction of the 342 units of solar energy coming in, about 168 is absorbed directly but about 324 is absorbed from the atmospheric radiation! The fraction of conduction and convection comes only to about 30%. It is true that the atmosphere gets some energy from conduction, but not most of its energy.

Scientific-sounding Junk

It is a real challenge for people without science background to sift through things like this. It sounds like science, but it is incredibly wrong. One way to help tell the difference is to observe how the author responds to criticism. Concerning the errors, do they offer an errata or do they ignore them, or worse, inject ad-hominem attacks on the critic? Saying that NASA "has a flimsy yet lucrative theory to foist on the taxpaying public" is playing into people's distrust of government, and trying to use that to bolster an argument, without actually strengthening the argument itself. It is implying motive without substantiation. I could do that too by suggesting that the author is starting with an anti-global warming position, and wants to prop it up with whatever emotional verbiage he can get away with to hide spurious arguments. Instead, I simply show how elementary and spurious his arguments are, and predict that he will not submit any corrections. I can point out the ad-hominem attacks on NASA as unbecoming of a scientific argument, and is useful only in a propaganda piece.

Another way that someone might tell if the argument is sound, is what sorts of errors are being raised. If the errors are of a technical nature, like the benefits of particular statistical tests, then it can be hard for a non-expert to tell. However, if the arguments have basic errors that can be confirmed in encyclopedias then it is much easier to tell. If the arguments include non-scientific, emotional, exaggerated language then it is much easier to tell that it is a propaganda piece and not a scientific piece.

Are there other ways that non-experts in a field can decide the merits of arguments? Perhaps someone will comment and add some more, and perhaps I'll think of some more. Mostly, being able to skeptically think like a scientist, regardless of your personal belief in something, is the most important skill to use in cases like this. I think it is an important thing to consider, in order to better win over the public to science.

Monday, February 22, 2010

A bit of must-read economics

In the face of Obama's new healthcare initiative, which includes provisions to cap the increases in insurance costs, you can read here a nice description of the problems of fixing maximum prices. When the Government caps prices to help people, it is a policy which goes in the category of "really simple, intuitive, well-intentioned, and wrong."

More people need to understand the proper functioning of the free market. This is true of people on "Main Street" as well as those on Wall Street. I think I may be becoming more Libertarian in my old age. :)

Coin flips and names (Evil problems in probability continued)

In my post about the girl-named-Florida problem, there is a factor in the analysis looking at the probability of having a girl named Florida given that you have two girls: P(F|2g).

This term is easily calculated as


which I used in the analysis.

Someone raised the question, "What would happen if (as we know) people don't tend to name two children the same (unless you're George Foreman)?" At first, this seems exactly like a coin flip problem: what is the probability of, in two coin flips, flipping heads on the first flip or flipping heads on the second but not both? It turns out that this is a different problem, and the result is surprising (at least to me). We have to be very careful what information we condition on, knowing that the English language is a little more fluid than we like when dealing with such problems. In the coin flip case we define


and it follows, given the probability of flipping heads is h,


which is just the standard result, subtracting off the possibility of having both heads. For h=0.5, this yields the standard result of P(h) = 0.5. As h gets close to 1, the probability of a heads goes way up, and thus the probability of both being heads goes way up. As a result, the probability of just having 1 heads goes to zero.

The situation with names is nearly the opposite: as the frequency of a name increases, the name is much more common. This makes it more and more likely that you will have someone with that name. The difference is in the conditioning information:


The analysis then goes:


which is exactly the same result as the case where one can name both of the children Florida! I was a little surprised by this result, but a quick simulation confirmed it as well.


from pylab import *
from numpy import *


N1=list(r1< f)
N2=list(r2< f)

case1=[n1 or n2 for n1,n2 in zip(N1,N2)]

print "Fraction allowing duplicate names: ",case1.count(True)/float(len(case1))
print "Theoretical Value: ",f+f-f**2

for n1,n2 in zip(N1,N2):
    if n1:
case2=[n1 or n2 for n1,n2 in zip(N1,N2)]

print "Fraction not allowing duplicate names: ",case2.count(True)/float(len(case2))

Simulation Result

Fraction allowing duplicate names: 0.1853
Theoretical Value: 0.19
Fraction not allowing duplicate names: 0.1853

Sunday, February 21, 2010

Magnetic therapy getting under my skin


Every year my family goes to the flower show in Providence. It's a nice time, seeing flowers in the middle of February, snacking on the pretzel and dip samples, and seeing all of the house and garden related vendors. It's tainted, however, by a particular vendor selling magnetic therapy items, such as bracelets, braces, and necklaces. The company is called Palmer's Global Magnetic Therapy, and I am bothered even writing their name here, giving them more exposure.

The Science

Their pamphlet has more science errors per square inch than any text I have ever read. For example,


Given that light is electromagnetic radiation, and I believe that light has been around a bit longer than people (even by creationist standards!), this definition is flat-out wrong. Saying that low-levels are "fought off" by the body, yet "higher levels are proving to cause gradual break down in health" is at best misleading: high levels of radiation, such as high-energy x-rays, break down organic molecules, but you aren't generally exposed to this in such high dosages. Either way, it is irrelevant to magnetic therapy where the magnets used are of such low intensity that no significant effect would be expected anyway.

On the medical side, this pamphlet is just as bad.


Let's take the last point first: "cancer cannot exist in a strong magnetic field". This is a true statement. What they left out is that, at that strength of magnetic field, non-cancerous cells also can't survive. It'd be like the statement: "cancer cells cannot exist is molten lava", which would be true...but useless and misleading.

The previous points, about the medical effectiveness of magnets, is also not correct. Although it seems to be challenging to have a blinded study of magnetic therapy, because people can easily test to see if the magnetics attract keys or other household items, careful studies have not found any effect of magnetic therapy. You can see some of them here, here, a nice wikipedia summary, and another very good summary of some other arguments against magnetic therapy.

I could go on and on with this, but I want to highlight a few things directly related to pseudo-scientific thinking. The following statement is indicative of the sort of thing, not limited just to magnetic therapy but to all forms of sham-medical treatments and much of pseudo-science as well.


Rephrased, a bit bluntly, this reads: "if you do our treatment for your ailment, and your ailment improves, then that is proof of the effectiveness of our treatment. if it doesn't improve, then you did something wrong, and it says nothing about our treatment". It's like the psychics who complain that the room isn't right, or their abilities are hampered by skeptical treatment, but otherwise they are perfect. Heads, I win. Tails, you lose. James Randi has pointed this out many times, with the people trying for his million dollar challenge. It is the type of thinking that protects you from ever being wrong, and thus places your statements outside of the realm of science. Unfortunately, it also generally means you're wrong, and are simply trying to avoid critique to keep the comfort of your misguided ideas.

Avoiding the FDA

In order to avoid the FDA, they have to put a disclaimer in, which reads:


However, does this disclaimer allow them to state the things above (about cancer), or these claims:


or these?


or these?


I'm no legal expert, but it seems to me that this is filled with medical claims, and simply stating "we are not making medical claims" should not be enough.

What to do?

I see these people every year, and every year I wonder what should I do. What is my moral obligation, what are my legal limits, what are my options? Sometimes I ignore them, but always feel bad afterward. I have a gut feeling that I have a responsibility to help save as many people from this scam as I can, especially since it is right in my backyard. I see people at the booth, and it drives me nuts. I try to educate my students, and anyone around me who will listen, but that doesn't feel like enough.

One suggestion that someone had was to set up a booth of my own, an anti-magenetic therapy booth. I'm not sure if this would either be allowed, or might be taken as libelous or something else that involves lawyers. There is the distinct possibility that it would simply make me look like a jerk, and work against the message that I would want to achieve.

A few years ago, I did approach them, and as gently as I could asked if they ever thought to consult a physicist concerning some of the claims in the pamphlet. It's a husband and wife team, and the wife was reasonably conversational. The husband was immediately aggressive and hostile. He questioned the need for such a thing, and when I pointed out a couple of straight-forward errors (not even the efficacy errors) he did not take it well. He even admitted to me, to my amazement, that he didn't care whether the claims were correct!

Another year I gave them a folder I'd prepared about magnetism, and some of the magnetic therapy studies. I even created an email address (brianthephysicist) for any questions they had...I never heard from them.

This year I submitted their website to the FDA website on "Reporting Unlawful Sales of Medical Products on the Internet". I have to admit that that felt good, but I doubt that in reality it will affect very much, if anything at all.

So I am still left with the questions: what should I do with this case? What is my moral obligation, what are my legal limits, what are my options?

Unfortunately, I don't really know.