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Old 22nd June 2010, 02:23 PM   #28
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Originally Posted by lomiller View Post
Greenhouse gasses controls surface temperature while atmospheric composition controls how much temperature decreases as you go up and how high you go before that relationship breaks down. If Venusís atmosphere were equally thick but opaque to neither IR nor visible light itís surface temperature would be approximately equal to itís blackbody temperature and if the there were any lapse rate at all temperatures would decrease from these.
In other words, if you radiatively decouple the atmosphere completely from its surroundings, so that it can only absorb and release heat through conduction, then blackbody temperature of the surface is your only constraint. Well, yeah. But that's an irrelevant scenario, with or without greenhouse gasses, because that doesn't describe the atmosphere of any planet.

IOW you canít do this the way Ziggurat is attempting, and it does indeed seem to be based on a blog posting by Goddard that has been thoroughly debunked. Lapse rate is ultimately a function of surface temperature not a cause of it.
No. Adiabatic lapse rate is a function of gravity and constant-pressure heat capacity. Surface temperature is part of the boundary condition for the problem (as already pointed out, this lapse rate won't hold over the entire atmosphere), but you're confusing boundary conditions with the solution to the problem.

BTW he does seem to be echoing a blog posting from last month, and one that has received considerable debunking.
And yet, your attempts to describe what's wrong with what I said are incorrect.
"As long as it is admitted that the law may be diverted from its true purpose -- that it may violate property instead of protecting it -- then everyone will want to participate in making the law, either to protect himself against plunder or to use it for plunder. Political questions will always be prejudicial, dominant, and all-absorbing. There will be fighting at the door of the Legislative Palace, and the struggle within will be no less furious." - Bastiat, The Law
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