New WUWT-TV segment: Slaying the 'slayers' with Watts

David_UK:

Michael, that is incorrect. Heat is transferred in all directions.

I’d say “heat energy is transmitted in all directions”.
Unfortunately thermodynamics still has language that harkens back to the caloric theory of heat.. and people still talking about heat flowing, as if it were a fluid. Even the wikipedia entry on heat does this “The second law of thermodynamics states the principle that heat cannot flow directly from cold to hot systems.”
Anyway, “heat” as used in thermodynamics is a technical term which refers to the net heat energy transferred from body A to body B during one complete thermodynamic cycle. Understood in this technical sense, the wiki entry is basically right, because “heat” by itself implies a “net quantity”.
This is a really awful terminology, and there’ s a bit of a movement to try and shift the language away from vestigial 19th century concepts, but it’s too entrenched yet for that to succeed.
Note also the oddity that people talk about dynamics processes using quantities like “energy” that don’t have an explicit time dependence. That’s because the early formulations didn’t have a mechanism for computing non-equilbrium quantities (that had to wait until statistical mechanics was developed).

Mark Bofill:

An IR bulb produces most of its radiation in the infrared. Mirrors are not very reflective very far into the infrared, so most of that infrared is getting absorbed and is heating up the mirror, which in turn is radiating infrared, part of which is heating up the bulb.

Interesting point, but doesn’t this also refute the slayer position? Reflection or back radiation, I thought their position was that cooler objects could not cause warmer objects to become warmer still.

I agree. That’s why I said “Both mechanisms (scattering and reemission) play a role in the inappropriately named GHG effect, so the function is still served in terms of refuting slayer quackery.” Though perhaps it could use more explanation:
The mirror absorbing infrared radiation from the light bulb then radiating it as heat energy in all directions is an example of reemission, and this is the mechanism that most closely matches the “backradiation” that the slayers claim is physically impossible.
Regardless of the mechanism (reflection or absorption followed by reemission) the mirror prevents some of the radiated power from escaping as efficiently. As long as you are continuously supplying current to the heat energy source, this will always result in the temperature “interior” to this barrier to increase from what it would have been without the barrier.
That’s “just physics”.

Anthony’s real experiment resembles Dr. Spencer’s “Yes, Virginia” thought experiment, except Dr. Spencer’s “cooler object” isn’t necessarily very reflective.
http://www.drroyspencer.com/2010/07/yes-virginia-cooler-objects-can-make-warmer-objects-even-warmer-still/

The ability to increase the heat source by 18F by simply adding a mirror to reflect the ‘Back Radiation’ must open up some good commercial opportunities given further development.
You’re right! For example, we could invent foil insulation for spacecraft — oops, that’s been done. We could use a reflective backing that could double as a moisture barrier on household insulation. Aw, darn. We could invent metallic reflectors for space heaters. Mmmm, too late. We could invent a nifty thing called a “space blanket”… rats! How about low-E glass with an IR reflective film? No? Gosh darn it, it looks like this isn’t even exotic physics, this is engineering to everybody but the Slayers.
But just how old is the concept? Well, they sell this stuff in grocery stores called “aluminum foil”. Those of us who know physics AND like to cook use it to loosely tent turkeys both to hold in moist hot air that helps the turkey inside cook without drying out and to reflect the radiant (IR) heat from the walls of the oven that would otherwise both dry out the surface of the turkey and cause the turkey to prematurely brown. We tend to remove it only at the very end of cooking, to permit that good old IR to make it to the turkey surface and brown it off nicely, all juicy and moist.
Those of us who are turkeys claim that a cold mirror can never make a heated source increase its temperature. Joe Postma, for example, has made this claim repeatedly. He and I have spent a megabyte’s worth or more of ascii character data debating this general issue. It is trivial to prove using absolutely ordinary physics that in fact one can easily make a heated object in radiative equilibrium hotter by reflecting its own thermal or nonthermal radiation back to it. The basis of the proof are things like “Maxwell’s Equations” (for the power carried by electromagnetic radiation) and “The First Law of Thermodynamics”, and they are truly first year physics stuff. The usual claim that is made to counter this is that if it happened it would make perpetual motion machines possible or other nonsense, claims that persist without proof in spite of direct, first year undergraduate computations that show that the second law of thermodynamics is perfectly happy with the heat flow involved.
Anthony’s nice, simple demonstration was long overdue as a direct refutation of their nonsense. However, it won’t work. They will claim that the heat rise was due to the interruption of convective flow in front of the mirror when it was placed nearby. They will claim that the iron was turned on so that the mirror was really hotter than 230 F. They will claim anything and everything not to be so very publicly proven wrong in an experiment, because as a general rule they pay lip service to the idea that grand claims need to be experimentally verifiable.
Obviously, this one isn’t.
And Joe, in case you are ready to continue to make claims otherwise, consider this one. One can take a COMPLETELY ordinary 100 watt light bulb and fasten a thermistor to its surface with a temperature tolerant glue. One can then repeat Anthony’s experiment, but instead of using a mirror, one can wrap the bulb tightly in aluminum foil in a completely distinct run. The tightly wrapped foil is going to have almost identical thermal contact with the surrounding air — it is an excellent thermal conductor (much better than glass!) and so it will be difficult to claim that there will be any significant insulation of the bulb by the thin aluminum layer per se.
What are you willing to bet that the temperature increase in the (now) completely opaque light bulb will not increase dramatically? Bear in mind that the bulb has to lose 100 watts in steady state between radiation and convection, and you’ve just blocked the visible radiation so that all of the power that WAS escaping the light bulb through the visible light channel is now being retained within the bulb. Bear in mind that we can probably find somebody with a vacuum chamber handy so that we can eliminate convection altogether from the equation (if the bulb can stand the pressure difference), so that the foil surrounding the lightbulb will have to heat to the point where it alone can radiate away most of 100 watts in steady state. Bear in mind that as the light bulb heats up, the argon/nitrogen gas inside (usually at around 0.7 atm) will increase its pressure. If one manages to double the operating temperature in K, one will double this to around 1.4 to 1.5 atmospheres, and risk actually making the bulb explode (especially if one operates it in a vacuum).
Personally, I think it is a no-brainer. Of course it will heat up. As Anthony’s experiment is already perfectly adequate to demonstrate. As countless other experiments with reflecting light energy from conducting surfaces and a perfectly consistent and intelligible theory of electrodynamics predicts.
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Again, thanks for this dialogue. The remote read IR thermometers that i mentioned above DO operate as described, these are the same $60 instruments that Dr Roy, Chris Monckton, Fred Singer, Judith Curry and others AGREED was proof of GHE in a lengthy CC thread in Feb 2011 involving 25 scientists. The Laser Focus World bolometer is a different system. An expensive, well calibrated thermal imaging camera with a 2% accuracy range may beat a $60 IR toy, but the results are the same. You can take a tuning fork to a concert and it will vibrate to the sounds of the concert. You can measure this ‘vibration’ with an optical motion detector, but your are NOT measuring amplification. A thousand tuning forks in a concert hall will not amplify the concert sound level. A thousand CO2 tuning forks in the sky will not amplify the Earth’s temperature.
I have been involved in 50 hr per week study of this most complex problem, every week for five years now. Early on i made statements, which were factual correct, based on the IMPLIED properties of CO2. I used the climatology short hand of ‘radiation = warming’, therefore back-radiation = warming. I stated in early articles “there was no back radiation”….there is undeniable scattering, but cooler does not make warmer, warmer still. Every object in our Universe has radiant energy, as even the Cosmic Background Radiation is 2.7K. The CO2 molecules in the atmosphere resonate as the OLR photons flow past, but lack the mass and structure to reflect energy back to Earth. Water vapor does have the mass and structure to redirect energy, but this energy cannot warm the source of the OLR. There are convective currents around the light bulb that were not controlled in this first run of the experiment. WIth proper convective conditions, the mirror/bulb experiment will show reflected light does not warm the surface that created the light.
REPLY: Oh please, those $60 units have a laser so that you can AIM THEM because there is no view screen, the laser is not an active part of the sensing system. They are passive sensors just like the more expensive models like the FLIR I have. Go to Harbor Freight, buy one, point it with the laser at a hot cup of coffee, turn off the laser, you’ll get the same reading. I have one of these cheap units, and I have coffee, need I prove this failure of your understanding too?
As for your convective complaint, YOU set the parameters for the experiment with Siddons diagram, with no mention of convection. I followed it as diagrammed. To claim I did it wrong after the fact is simply disingenuous. – Anthony

This test measures the temp of the bulb surface. It does not establish that reflecting radiation back to the source (the filament) increases the power output of the source. The ghg theory claims that downwelling IR causes the source of the IR, the earth’s surface, to emit more power – this is what siddons is taking issue with.

@richard Smith. If you believe that then demonstrate that is the problem and remember that it was the skydragon folk on their own web page who used that as an example. So if your defending their point you need to demonstrate with experimental data how it is wrong. Just stating theory on why it might be wrong won’t disprove an actual physical experiment.
You can’t handwave away experimental data. You have to do experiments of your own to disprove experimental data. This is why data collection and retention matter in science.

I admire Judith Curry for her patience with some theorists who will use any thread to tout their own pet theories, like the iron sun theory. It might not be accepted science by a long shot, but it does no harm.
Also there is a parallel here to how skeptics are treated at f.ex Realclimate – Watts Up should not be a place with a “borehole”. So “put up or shut up” is not the way it should be.
Let people have a say – and if they have nothing of substance, then most times they will be arrested by the community. Nothing wrong with that.
It is open debate – something skeptics have always been better at then alarmist.
A tradition we should be proud of.

Nice experiment, Anthony!
Re the Slayers, they tried to recruit me a year or so ago. I declined after reading some of their book. I gave up arguing with them in emails when it became clear that no amount of factual, real-world evidence and sound logic would dissuade them.
It is well-known in engineering circles that colder objects radiate heat back onto hotter objects. We design fired furnaces with that concept. Examples include gas-fired hot water heaters, power plant boilers, and industrial furnaces. There are many millions of these fired furnaces operating around the world.
If the Slayers were right, the fired furnaces don’t work.
I’m enjoying reading the comments on this post.
For any readers who insist that CO2 cannot absorb IR and re-emit, please go to a technical library, find a Perry’s Chemical Engineering Handbook, 5th Edition, and have a look at page 10-57. That page discusses the emissivity of CO2.

Greg House says:
May 27, 2013 at 8:53 am
Back radiation is real and the the “greenhouse effect” as presented by the IPCC is non-existent. There is no contradiction here. Because the “greenhouse effect” as presented by the IPCC is not just about existence of back radiation. The IPCC goes beyond that and claims that this back radiation has a warming effect on the surface. Exactly this warming effect (this includes slowind down cooling) is physically impossible.
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So, if back radiation (of energy) is possible, please explain exactly what happens to that energy when it reaches the surface? Seems to me your position requires it to vanish without trace which, I humbly suggest, is a far greater violation of physical laws than having it reduce the cooling of the surface!
Please explain clearly why it ain’t so (in other words, what does happen to all that back-radiated energy)?

Anyone living in the South or other hot areas of the Country that have installed e-glass windows can do this experiment without any ado. I have installed e-glass windows in my south Florida home. These windows have a Solar Heat Gain Coefficient (SHGC) of .21. “Solar Heat Gain Coefficient (SHGC) represents the fraction of the solar energy that is transferred through the glass of a window. SHGC values range from 0 to 1. The lower a window’s SHGC value, the less solar heat is transmitted through the window. ” This very low .21 SHGC is excellent at blocking solar radiation from passing through the window.
One day while standing outside near my front, west facing windows in the late afternoon, I noticed I was feeling heat from those windows, reflected solar energy that could not pass through the e-glass. The air was warmer up to about 4 feet from the windows.
Now I cannot and do not claim to know what this all means however, the question is can these air molecules that have been warmed by the reflected solar energy have an additional heating effect back on the windows themselves. If they do, this would be a GH effect would it not.