Re: atmospheric blanket / greenhouse effect

["John S. Denker" <jsd@AV8N.COM>]

On 07/28/2003 01:30 PM, Robert Cohen wrote:
> > Are you claiming the magnitude of your effect is
> > independent of the thickness of the atmosphere?
>
> Yes and no.  The assumptions of absorption are certainly dependent on
> the thickness of the atmosphere.  A very thin atmosphere won't absorb
> 100% of the outgoing IR, for example.  However, if you can meet my
> assumptions (or close to it - say, 80%), then in a sense it is
> independent of the thickness of the atmosphere.

I disagree.

For a thick atmosphere, if you want a self-consistent
theory, you need to divide the atmosphere into layers
and iterate your argument.  The Nth layer shields the
N-1 lower layers as surely as the first layer shields
the surface.  The effect is cumulative.  The radiation
is _diffusing_ outwards.

It would be quite a coincidence if the atmosphere's
thickness just happened to exactly equal one mean-free-path.