Reply To: Where did my post go?

[HermannH]

Brian H wrote: The physics underlying the CO2-temp connection is not just weak, it’s missing. Read or re-read http://arxiv.org/pdf/0707.1161v4 (Falsification of Physics Greenhouse Effect)

I did just that, well almost. I read this annotated version (sorry, German only and possibly slow link).

Needless to say the author finds many faults with the paper; his annotations to the original are in blue. I will quote just one short piece here that deals with the apparent paradox that an atmosphere that is far colder than earth’s surface somehow manages to heat the surface. Gerlich and Tscheuschner claim that this is equivalent to a perpetual motion machine of the second kind. I chose this example because the arguments can be easily understood by a layman.

Gerlich and Tscheuschner (3.9.3 A paradox):

The renowned German climatologist Rahmstorf has claimed that the greenhouse effect does not contradict the second law of thermodynamics [141]:

“Some `sceptics’ state that the greenhouse effect cannot work since (according to the second law of thermodynamics) no radiative energy can be transferred from a colder body (the atmosphere) to a warmer one (the surface). However, the second law is not violated by the greenhouse effect, of course, since, during the radiative exchange, in both directions the net energy flows from the warmth to the cold.”

Rahmstorf’s reference to the second law of thermodynamics is plainly wrong. The second law is a statement about heat, not about energy. Furthermore the author introduces an obscure notion of “net energy flow”. The relevant quantity is the “net heat flow”, which, of course, is the sum of the upward and the downward heat flow within a fixed system, here the atmospheric system. It is inadmissible to apply the second law for the upward and downward heat separately redefining the thermodynamic system on the fly.

Here is Ebel’s reply as translated by me:

The second law of thermodynamics is not redefined in Rahmstorf’s quote. In equation (70) the emission of a body is handled correctly, that is implicitly independent of the surroundings. The surroundings can be warmer. Consider the case of a cooler sphere inside a hollow sphere that is hotter. Where do its emissions go? Why is it that the outside sphere cools down faster if the interior sphere is colder? How does the outside sphere know when to stop heating the inside sphere; once equilibrium is reached? The explanation is simple if one takes into account that the inside sphere emits radiation as well: When it is very cold it emits almost nothing so the emissions from the outside hollow sphere encounter almost no compensation the other way. With rising temperature the inside sphere emits more strongly until, when temperature equilibrium is reached, as much power is emitted by the inside sphere as it receives from the outside hollow sphere. Prevost knew this already 200 years ago. If you have heat radiations in opposite directions the difference is the net heat transfer.

If you want to see the Gerlich and Tscheuschner paper debunked in English have a look at this page.
Or a much shorter piece here.
There is also a formal proof that the greenhouse effect exits, available here.

So Brian, I hope you opened your champagne bottle on New Year’s and didn’t waste it on this paper.

BTW, you still didn’t respond to my accusation that you blatantly misrepresented the Lawrence Livermore Laboratory position on AGW.

And there is something else you need to do: If you are still convinced that the greenhouse gas effect does not exist you should remove the ‘MAXIMIZE CH4’ part from your signature.