Even More Trouble with AGW.


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The faulty analogy between CO2 absorbtion of a narrow band of infra red radiation and a green house is even more troublesome. By analogizing the CO2 to the glass window of a hothouse and postulating "back radiation" from the gas get a violation of the First Law of Thermodynamics. The back radiation actually produces more energy than actually fell on the earth.

Please see this item for a fuller explanation:

http://hockeyschtick.blogspot.com/2010/06/why-conventional-greenhouse-theory.html

Ba'al Chatzaf

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It repeats the same point: If a body can heat itself by absorbing its own radiation, and thereby emit more radiation, then it is necessarily emitting more radiation than its receiving."

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<br>This article has an obvious logical flaw. By "its own radiation", I don't think that anybody (except the author here) means that the Earth is warming itself through radiation that it produces, but that DOESN'T come from the sun.

<br>From what I understand, the Earth receives radiation from the sun. Some of that radiation is absorbed and turned to heat, the rest is re-emitted, and then absorbed by greenhouse gasses, which further heat up the surface.<br>

I see more and more problems as the article goes on. Do you seriously believe any of it?

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<br>

It repeats the same point: If a body can heat itself by absorbing its own radiation, and thereby emit more radiation, then it is necessarily emitting more radiation than its receiving."

<br>

<br>This article has an obvious logical flaw. By "its own radiation", I don't think that anybody (except the author here) means that the Earth is warming itself through radiation that it produces, but that DOESN'T come from the sun.

<br>From what I understand, the Earth receives radiation from the sun. Some of that radiation is absorbed and turned to heat, the rest is re-emitted, and then absorbed by greenhouse gasses, which further heat up the surface.<br>

I see more and more problems as the article goes on. Do you seriously believe any of it?

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The flaw is the Stefan Boltzmann law. A body emits energy at a rate of its absolute temperature to the 4 th power. If the earth got hot enough it would emit energy fast enough to be in equilibrium with incoming solar energy. The so-called Green House effect cannot produce indefinitely high temperatures If it could we would have a perpetual motion machine.

The flawed Greenhouse analogy has been busted a dozen ways from Christmas. 1. The IPCC predictions are invariably hotter than the actual temperatures. 2. the IPCC GCMs do not take into account all natural feedbacks and heat redistributions. 3. The IPCC models ignore the fact that real Greenhouses work because they thwart atmospheric convection. That is why your car gets very hot when you park it in the sun with the windows closed. 4. The IPCC models perversely down weight the PDO as a heat redistribution mechanism and underestimate oceanic cooling.

Back radiation is at odds with thermodynamics. Here is a hint. Anything that contradicts a basic thermodynamic law is WRONG.

We can doubt Relativity. We can doubt Quantum Theory. But thermodynamics is as close to TRUE as we get.

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Back radiation is at odds with thermodynamics. Here is a hint. Anything that contradicts a basic thermodynamic law is WRONG.

We can doubt Relativity. We can doubt Quantum Theory. But thermodynamics is as close to TRUE as we get.

If it works the supporting theory is validated at least on the practical level. There is no actual need for another, better theory, until something comes along that doesn't work or fit. Why does the sun "come up" in the morning? Easy, the sun revolves around the Earth.

--Brant

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The flaw is the Stefan Boltzmann law. A body emits energy at a rate of its absolute temperature to the 4 th power. If the earth got hot enough it would emit energy fast enough to be in equilibrium with incoming solar energy. The so-called Green House effect cannot produce indefinitely high temperatures If it could we would have a perpetual motion machine.

Maybe so, but the Earth is nowhere near hot enough yet to be in equilibrium with incoming solar energy. Let's calculate how hot the Earth would have to be in order to be in equilibrium with the incoming solar energy.

The earth receives 3.85 x 10^24 J of energy from solar radiation per year. Per second, this is 1.22083*10^17 J. Now, according to the Stefan-Boltzmann law, if we divide this number by the surface area of the Earth (4*pi*R^2 = 5.09806*10^14 m^2), and by the Stefan-Boltzmann constant (5.670373 x 10(-8) W/(m^2)/(K^4), and then take the 4th root, we should get the right temperature, which is 19103.4 K! That's ridiculously hot!

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Back radiation is at odds with thermodynamics. Here is a hint. Anything that contradicts a basic thermodynamic law is WRONG.

How exactly is back radiation at odds with thermodynamics? Radiation does not have to obey the laws of thermodynamics, it can travel in any direction (including downwards from colder regions of the atmosphere to hotter ones), regardless of the sources of heat around it.

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The flaw is the Stefan Boltzmann law. A body emits energy at a rate of its absolute temperature to the 4 th power. If the earth got hot enough it would emit energy fast enough to be in equilibrium with incoming solar energy. The so-called Green House effect cannot produce indefinitely high temperatures If it could we would have a perpetual motion machine.

Maybe so, but the Earth is nowhere near hot enough yet to be in equilibrium with incoming solar energy. Let's calculate how hot the Earth would have to be in order to be in equilibrium with the incoming solar energy.

The earth receives 3.85 x 10^24 J of energy from solar radiation per year. Per second, this is 1.22083*10^17 J. Now, according to the Stefan-Boltzmann law, if we divide this number by the surface area of the Earth (4*pi*R^2 = 5.09806*10^14 m^2), and by the Stefan-Boltzmann constant (5.670373 x 10(-8) W/(m^2)/(K^4), and then take the 4th root, we should get the right temperature, which is 19103.4 K! That's ridiculously hot!

Does incoming energy include heat reflected back into space off ice, clouds or anything else? Does it account for precession in rotation or the difference between what the poles receive and the equator? Etc. I don't know these things. I do know you seem to know what you are talking about, but I hope it's not just more sophistication in scientific declamation than what Bob can do, making it an implicit argument from authority.

--Brant

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Does incoming energy include heat reflected back into space off ice, clouds or anything else? Does it account for precession in rotation or the difference between what the poles receive and the equator? Etc. I don't know these things. I do know you seem to know what you are talking about, but I hope it's not just more sophistication in scientific declamation than what Bob can do, making it an implicit argument from authority.

--Brant

Energy reflected is energy not absorbed. Reflective bodies are poor emitters of energy. Blackbodies which absorb energy at all frequencies are ideal radiatiors of energy. Albido (reflectiviy) is what keeps the earth, atmosphere and seas cooler. See Blackbody Radiation.

I do not make arguments from authority. But I quote from works I have vetted personally or from articles that appear in scientific journals or quote results from articles that appear in scientific journals. By and large I rely of the expertise of the scientists and mathematicians to provide any "authority" applicable.

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Does incoming energy include heat reflected back into space off ice, clouds or anything else? Does it account for precession in rotation or the difference between what the poles receive and the equator? Etc. I don't know these things. I do know you seem to know what you are talking about, but I hope it's not just more sophistication in scientific declamation than what Bob can do, making it an implicit argument from authority.

--Brant

Energy reflected is energy not absorbed. Reflective bodies are poor emitters of energy. Blackbodies which absorb energy at all frequencies are ideal radiatiors of energy. Albido (reflectiviy) is what keeps the earth, atmosphere and seas cooler. See Blackbody Radiation.

I do not make arguments from authority. But I quote from works I have vetted personally or from articles that appear in scientific journals or quote results from articles that appear in scientific journals. By and large I rely of the expertise of the scientists and mathematicians to provide any "authority" applicable.

Noted, but my post was addressed to Gary, not you, in case you think I was accusing you of something I wasn't. I can see my wording wasn't quite right.

--Brant

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