Re: [Phys-l] CO2 Doesn't Heat the Atmosphere ...

[Jack Uretsky <jlu@hep.anl.gov>]

Hi guys-
	I think you have to deal with the words as stated, and not try to 
rephrase them.  The statement is (in part): "A volume of gas in Local 
Thermodynamic Equilibrium (LTE) cannot be heated by CO2."
	The statement does not say what the "volume of gas" is in 
equilibrium with, so it is incomplete.  The statement is probably a 
quotation from some source, so anyone interested should look at the 
source.  I'm not even sure, at this point, what is meant by "equilibrium" 
in the statement.
			Regards,
				Jack

"Trust me.  I have a lot of experience at this."
		General Custer's unremembered message to his men,
		just before leading them into the Little Big Horn Valley




On Tue, 31 Aug 2010, brian whatcott wrote:

>  On 8/31/2010 3:09 PM, Folkerts, Timothy J wrote:
> > ... or so it is claimed at a quite popular anti global warming blog (
> > http://wattsupwiththat.com/2010/08/05/co2-heats-the-atmosphere-a-counter
> > -view/ )
> >
> >
> >
> > Specifically, they assert "A volume of gas in Local Thermodynamic
> > Equilibrium (LTE) cannot be heated by CO2."  I was hoping some of the
> > more thermodynamically minded of you might take a look and present your
> > opinion.  I wanted to be a little more sure before I tried posting a
> > reply there.
> >
> >
> >
> > My first impression is that this statement is correct as far as it goes,
> > but that the CO2 is NOT in LTE with the N2.
> >
> >
> >
> > There is a photon gas that is not in thermal equilibrium with the
> > physical gases in the atmosphere.  The photons CAN transfer energy to
> > the CO2.  This means the CO2 is NOT in thermal equilibrium with the N2
> > (the CO2 always being slightly warmer due to the interaction with the
> > "hot" photon gas).  This allows the CO2 to indeed transfer energy to the
> > N2 and provide a warming to the atmosphere.
> >
> >
> >
> >
> >
> > Tim Folkerts
> I haven't been paying much attention - so my internal model may be out of
> whack - but wasn't the heating mechanism described something like this:
>  solar irradiation in the visible is the input  for surface temperature
> rise,
> from which the far IR re-radiates - unless it is absorbed by atmospheric
>  components - methane, CO2 etc., etc.
>
> Does "local thermal equilibrium" mean  "not stirred, not transported,
> not heated"?
> If so, then ANY material in local thermal equilibrium cannot be
> heated...by definition.
> So much for my insights....
>
> Brian W
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