No such thing as the greenhouse effect?

This Big PDF paper By a German Mathematical Physicist and some other guy purports to entirely refute the existence of any greenhouse effect. He has an extraordinary facility to present simple concepts in the form of impenetrable math and diagrams that don’t seem to convey any information to me.

So, I come here, not to debate Global Warming, or Anthropogenic Global Warming, nor even the existence of increased temperatures anywhere. What I want to know is, am I totally out of my mind to find this stuff deliberately opaque? I generally walk lightly through the math parts of really technical reports, and I freely admit it. But this one leaves me counting my fingers. Not to check the arithmetic, but to assure myself that I still have all of them.

Help me dopers, of the Physics and Mathematical persuasion. Am I failing to understand simple science? Am I just too stupid to listen in on this discourse?

Tris

Can’t help with the math, but you can demonstrate a greenhouse effect easily enough. Just look at anything that doesn’t have an atmosphere, like the moon, and compare its temperature (especially the light and dark variants) to Earth’s.

That’s retention of radiant energy, debatably based on such simple concepts as specific heat, and the greenhouse effect has to do with the behaviors of certain gases in particular.

I’ll take a look at the PDF on Friday, if no-one else has weighed in by then. Without looking at it, be very aware there’s often a difference between what scientists and science actually say and what the media reports it as saying. I saw an article not too long ago where two researchers were able to expand the wave function of a particle to be greater than the gap between two prisms- a quantum effect, roughly a form of quantum tunnelling- and the article reported it as FTL travel and transmission of data being possible. (Simply because one scientist mentioned used it for data transfer.) One thing has absolutely nothing to do with the other!

Call me sceptical. Look at the section entitled “Scientific error versus scientific fraud” - it cites films on global warming debunking and a Channel 4 (UK) series. Even worse, look at the references - they’re citing Wikipedia (see [196] and [197]!)

I very much doubt that this paper has been peer reviewed or published in any sort of reputable publication. Not only does it feel completely amateurish, but it’s way too long even for a journal (speaking from the viewpoint of a computer scientist, anyway - I don’t know what the standards are for physics).

The abstract also states that “According to the second law of thermodynamics such a planetary machine can never exist.” This is simply false. The greenhouse effect is completely consistent with the second law of thermodynamics.

Heh heh. I went looking through the article, and one reference jumped out at me:

Reference 143 points us to:

For those unfamiliar with this journal, it’s the Mad Magazine of the peer-reviewed-journal world.

Either this article is a vastly complicated joke, or its authors are morons.

Daniel

There is an odd sense in which the “greenhouse effect” doesn’t exist, or more accurately is misnamed because greenhouses don’t exhibit it.

The idea is that a glass greenhouse gets warmer because the long wavelength thermal infrared radiation coming from whatever sunlight hits inside the greenhouse can’t pass outward through the glass.

However, with the advent of plastic greenhouse construction materials, which are transparent in the thermal infrared, greenhouses still get warm, and more careful analysis shows that the infrared effects are neglible and greenhouses get warm because they capture air inside and don’t let the wind blow the heat away.

At least, this is what I read somewhere.

I didn’t look at the paper, and I don’t gather that this interesting point is directly on subject, just throwing it into the mix for fun.

First posting here. Lurked for a while but when this came up I had to reply.

I am not a climate scientist, but work in a closely related field and know many of these equations intimately. Suffice to say, if the science were flawed in the way he describes, the interpretation of satellite observations would be impossible (whereas we can model them extremely well ) and numerical weather prediction models would produce absolute rubbish.

To answer the original question, yes the paper is extremely opaque. I don’t think the maths itself is particularly difficult (although much of it is superfluous) but his grasp of physics seems so poor that his arguments are tenuous at best.

I don’t have the inclination to go through this point by point (which I believe is not what the OP intended), but one particularly specious argument is the “In the kitchen” example where he says that the fact that a water-filled pot on a burner not getting red-hot refutes global warming. He says that the water in the pot is the analogue of the greenhouse gas and yet the radiative properties of the water are completely inconsequential in this scenario.

The first forty pages or so are devoted to the insight (already noted here) that greenhouses don’t work by the greenhouse effect. This is common knowledge in the climate change community (although knowledge of greenhouses is not actually a requirement!) and arguments such as these against global warming via analogy with greenhouses or cars in the sun are naive at best.

That’s all I have.

I don’t hink this paper is a joke, but I do believe Dr. Gerhard Gerlich is…

Cite.

This is IMHO of course.
OK, I have not read the whole paper, but I did just read the section on the conservation laws of magnetohydrodynamics and came to the conclusion that this guy is a serious idiot or completely insane!

Well, given that famous statement about not attributing to malice what can be attributed to stupidity, I will refrain from arguing that it is deliberately opaque. It is, however, very opaque…as it needs to be in order to confuse a subject where at least some of the principles are very basic. I.e., it is very simple to calculate the surface temperature of a “graybody” earth in the absence of any greenhouse effect and show that it is more than 30C below the actual average surface temperature.

Some concepts regarding the greenhouse effect really are more complicated. E.g., it is true that real greenhouses are not demonstrations of this effect and thus it is misnamed. In fact, in order to have a greenhouse effect it is necessary to include the fact that in the troposphere (the lower portion of the atmosphere) the temperature decreases with height.

That being said, I believe that the greenhouse effect can be demonstrated using some fairly simplified models…such as a two-layer model of the atmosphere. One doesn’t have to go to the full structure of the atmosphere to demonstrate the basic effect and magnitude of the effect…just to calculate all of the details.

By the way, here is a page with links to further discussions about this paper.

whew.

Thanks.

I think.

Somehow I still end up counting my fingers.

Tris

By the way, a grad school colleague of mine, Arthur Smith, has done the best job that I have seen of wading through the meat of this paper and actually explaining where they are wrong. He begins in this comment on a N.Y. Times blog webpage and continues the discussion in his subsequent comments on this page. His conclusions are completely in line with the impressions that I had when I looked over that section of their paper yesterday.

This paper, along with this one claiming the non-existence global temperature that was all the rage in skeptic circles a few months ago, have a unique style that is a little hard to explain. Basically, they do calculations that are basically correct…often very pedagogical and already well-understood…and then mix it in with bizarre interpretations that are not really implied by their calculations. (In fact, as Arthur points out, some of their calculations are actually better interprettted to argue precisely against their conclusions.) They also get hung up on very binary views of the world. (E.g., either you can rigorously thermodynamically-define what the average temperature is or it is a completely meaningless concept. The reality is that temperature itself can only be rigorously thermodynamically-defined in a system which is completely in equilibrium which means, in the real world, never. However, that doesn’t stop it from being a very useful scientific concept even in the real world.)

To what extent do the authors of these papers really believe what they are writing? I find it a little hard to believe that they really do but maybe the mind is capable of greater self-delusion than I give it credit for.

Yeah, that is a distinct improvement over the bulk of “explaining” that was going on in this . . . debate(?).

Actually, this, and two discussions I have been involved in on cosmology have been very good for my intellectual health. I think I have read more hard science in the last two weeks than in the previous year!

(One of my friends said, “damn, what kind of stuff do you read where “the average of the fifth integral is not equal to the fifth integral of the average” is a counter argument?” giggle giggle. But, it’s good for my head.)

Thanks a lot for your scholarship!

Tris

Ah, but you calculated it wrong! You can’t just treat the Earth as a radiating greybody, and then calculate the temperature that balances the energy in and out!

You have to start off with a sphere at absolute zero, and radiate energy onto a hemisphere. Then model the temperature rise with time, the changing conduction patterns through the bulk, the shifting surface temperature distribution and consequent re-radiation, until you reach a steady state. Then average the temperature.

This takes an insane amount of time and computing power, and therefore can’t be done. It’s even more difficult when you spin the sphere and tilt its axis. So the 30 C figure is meaningless, and therefore there is no greenhouse effect.

Well, that’s what I got from the paper. That, and an urge to stick my finger in the author’s eye.

matt: That sounds like a pretty good summary to me although you left out the part where they complain that the schematic diagrams of radiative fluxes “do not fit in the framework of Feynman diagrams, which represent mathematical expressions clearly defined in quantum field theory” (p.60) or the part where they note that to do climate modeling correctly “it would conceptually be necessary to go into the microscopic regime, which is described by non-equilibrium multi-species quantum electrodynamics of particles incorporating bound states with internal degrees of freedom, whereby the rich structure and coexistence of phases have to be taken into account in the discussion of natural situations.” (p. 80)

Honestly, if I didn’t know that one of the authors has a long history as a climate change “skeptic” I would suspect that this paper was a Sokal-style hoax.

Dang, something that jshore and I both agree on.

AFAICT, this is not science, just some guys’ wild ideas made very confusing.

w.

So, I discussed it with my friend, who sent me the article. He got a little glassy eyed when I reviewed Dr. Smith’s analysis, and I admit I was using notes. However, when I explained to him that the Second Law of Thermodynamics did not in fact prove that your sweater can’t keep you warm, he decided that perhaps there was something less than rigorous in the analysis. I imagine it will take him a day or two to find yet another guy with a degree to “debunk” global warming.

The really funny part is, until he began spamming me with “authoritative evidence” against it, I really was not much convinced, having read nothing but news reports, which I generally ignore. But I noticed that my replies to him referenced sources like NSF, AAAS, NASA, GISS, and came with descriptions of data and methodologies, his sources were from Economists, think tanks, and “Foundations” with six members. My friend says that objecting on that basis is ad hominem argument. I consider it noise reduction.

So, thanks for the boost.

Tris

Sounds like a fun back-and-forth you have had there with your friend! By the way, I thought I would mention that Arthur Smith wrote up his arguments more formally and submitted the resulting manuscript [PDF file] to the same preprint archive as this paper itself is on. (I don’t know if he is going to try to get it published anywhere…It may be hard to submit to a refereed journal simply because it is responding to a paper that is extremely unlikely to ever see the light of day in any reputable peer-reviewed journal…and, as Arthur notes, the basic concepts are not new. It is just necessary to re-explain them after Gerlich and Tscheuschner [G&T] have confused them so.)

I agree with your sweater analogy in response to their Second Law of Thermodynamics argument in Section 3.9 of their paper although I have seen a defender of G&T object to such an analogy because he argues that the sweater is more just blocking convective heat transfer (just like a real greenhouse does) rather than radiatively absorbing and re-radiating it.

Leaving aside the issue of whether this matters, however, I think it is possible to come up with a system involving only radiative heat transfer that illustrates the same sort of effect and is so simple it could be given as a homework problem in an introductory physics course when they got to radiative heat transfer. (In fact, you could probably find such a problem in an introductory textbook.) Namely, you take three parallel infinite sheets in otherwise empty space that thermally-communicate only by radiation. They are all perfect blackbodies and one is held at a constant temperature. You could call the sheets A, B, and C but it will make the analogy clearer if we call them “Sun”, “Earth surface”, and “Top of atmosphere”. Of course, the sun will be the one we hold at a constant temperature, call it T_S.

First, consider the case when you only have two sheets. Then, it is a simple problem in radiative physics to show that the “earth surface” sheet in the steady-state will have a temperature T_E = 0.8409*T_S where the numerical constant is the 4th root of 1/2.

Now, go to three sheets (in the order “sun”, “earth surface”, “top of atmosphere”). Now, it is only slightly harder to show that the temperature of the “earth surface” sheet is T_E = 0.9036T_S and of the “top of atmosphere” sheet is T_A = 0.7598T_S where the two numerical constants here are, respectively, the 4th root of 2/3 and the 4th root of 1/3.

So, this is a very elementary radiation physics problem that seems to exhibit the exact same feature that leads G&T to claim there is a violation of the 2nd law: namely, the addition of the “top of atmosphere” sheet has caused the temperature of the “earth surface” sheet to go up from what it was in its absence and yet the “top of atmosphere” sheet is colder than the “earth surface” sheet so, by the 2nd law, heat should not be flowing from the “top of atmosphere” sheet to the “earth surface” sheet.

Of course, really we know that the net flow of heat is from the “earth surface” sheet to the “top of atmosphere” sheet…and thus there is no violation of the 2nd law. The “earth surface” sheet is only warmer now because the “top of atmosphere” sheet acting as an intermediary between the “earth surface” sheet and the vastness of space is slowing the net flow of the heat from the “earth surface” sheet out into space!