This is going nowhere , so this is my last post .
First , Why is anybody continuing to parrot the 33c bogeyman ? How can
anyone defend using anything other than the unweighted energy impinging
on the planet as the null hypothesis ? That's about 9 or 10c , NOT 33c
. I challenge anybody to show me the spectrum which will produce that
extreme an "anti-greenhouse" effect . If you can't follow those
highschool level computations , further discussion is pointless .
In any conservative system like energy , computations in which are in
fact linear , the average over a cycle is the equilibrium value . Any
particular spectrum will come to an equilibrium temperature determined
by its correlation with its source and sink spectra .
It is absolutely absurd to contend as MS does that sink spectra
don't matter . I suggest a simple experiment for him : Take 2 identical
incandescent bulbs . Paint one of them . Plug them into the same
voltage . Explain why the painted bulb burns out first . And , by the
way , one of the most elementary exercises in heat flow is to show that
Fourier's heat equation , which essentially says heat "pimples" will
flatten out , is to show that the temperature of a plate between a hot
boundary and a cold boundary will come to a flat temperature
gradient between them . So the temperature of the cold edge will affect
the temperature of all warmer points on the plate . MS never has
replied to even my assertion that if the cosmic background temperature
were 200k instead of 3k , we would be about 16k warmer . He rejects
StefanBoltzmann but offers nothing quantitative in its stead .
Neither a greenhouse effect nor the static pressure gradient can
explain the extreme surface temperature of Venus . I don't claim
to understand the vertical structure of atmospheres very well , which
is one reason why the initial blog post here interested me, and the
post did help my getting a better understanding of the parameters
. But one convenient attribute of dealing with a Gaussian surface like
a sphere is that certain constraints can be asserted over them . Most
importantly , the energy density within an externally heated sphere
cannot exceed that of the surface without an internal source . Any
spectrum , like that of CO2 has a calculable equilibrium temperature
dependent on its correlation with the spectra of its heat sources and
sinks . It's not open ended , subject to runaways .
If an atmosphere is such that it effectively absorbs a large
enough fraction of incoming radiation to be warmer at some level than
its "lapse rate" , convection will stop . It will come to a uniform
temperature inside that shell . It will NOT continue getting hotter and
hotter within that shell unless there is an internal source of heat .
It is known Venus has substantial geothermal activity and a very thick
insulative atmosphere . That , as I have seen more precisely stated in
other blogs , not some infinitely cascading "back radiation" , not some
constant pressure gradient , is the only possible cause of Venus's
extreme surface temperature .
Sorry if I come across a little rough , but when no-one puts in the
work to get their heads around even the most basic computation of the
temperature of a ball in our orbit , they clearly have never put the
work in to understand how to "think" physics at a useful level .