Over on last year’s excellent SOD venusian mysteries part two thread occasional Talkshop contributor Bryan linked a .pdf by Gerlich and Tscheuschner which has large relevance to the current interest in Nikolov and Zeller’s and Hans Jelbring’s hypotheses. This is a technical paper and I don’t understand all the squiggles, but I’m sure the recent addition to the Talkshop of some real atmospheric thermodynamic expertise will make this an interesting thread.
Rather than the usual abstract at this point I’m going to quote the results section:
arXiv:1003.1508v2 [physics.ao-ph] 9 Mar 2010
On The Barometric Formulas
And Their Derivation From
Hydrodynamics and Thermodynamics
Version 2.0 (March 9, 2010)
By combining hydrodynamics, thermodynamics, and imposing the above listed assumptions
for planetary atmospheres one can compute the temperature profiles of idealized atmospheres.
In the case of the adiabatic atmosphere the decrease of the temperature with height is described
by a linear function with slope −g/Cp , where Cp depends weakly on the molecular mass. As
elucidated in our paper [4, 3] mixtures of gases are covered in the context of Gibbs ther-
modynamics. Since the measurable thermodynamic quantities of a voluminous medium, in
particular the specific heat and the thermodynamic transport coefficients, naturally include
the contribution from radiative interactions, we cannot expect that a change of concentration
of a trace gas has any measurable effect. At this point, it is important to remember that the
barometric formulas do not hold globally but have only a limited range of validity.
What I’d like our (hopefully) resident experts to elucidate for us, is how limited the range of validity is. My guess is that G & T are being conservative and covering their behinds given the heavy flak they got over their earlier paper. Something that looks impressive to my admittedly rapidly scanning and somewhat glazed eye is their inclusion of horizontal winds, coriolis and centrifugal forces and etc in the analysis.
The paper is available here.
This thread will be moderated for relevance – so watch it Adolfo. And Joe, I know they mention the magic word centrifugal, but this does not give you carte blanche to scatter half baked nonsense here. Engage brain before fingers please 🙂