But....
The blackbody radiation from Earth (at 4-5 microns) far outstrips the capacity for CO2 to absorb it all (until our atmosphere gets up to >85% CO2).
You're saying there's enough IR radiation in the 4-5 range, that it would take a atmosphere made up of 85% CO2 before the IR was absorbed to extinction??? Reference please. I'd love to know where you got this from.
This is completely at odds with everything that I've read. Here's a link to a wikipedia page with showing the atmospheric transmission of IR.
http://en.wikipedia.org/wiki/Image:Atmospheric_Transmission.png
===
This seems (to me) to be a good page on describing the IR adsorption physics behind AGW - and a quote for you samewise
It is generally accepted that the concentration of carbon dioxide in the atmosphere is already high enough to absorb almost all the infrared radiation in the main carbon dioxide absorption bands over a distance of only a few km
You caught me!
I knew when I wrote that, about the 85%, I'd get in trouble. Hopefully the smiley face indicated something to be looked at more closely. Thanks for finding that reference for me (I figured if it was wrong, then someone would let me know).
And Thanks for the other reference too, I have some more studying to do!
One point I think I can ask about:
The theory of AGW is that as the atmosphere becomes more "optically thick" with CO2, there is more CO2 available to reabsorb emitted IR from the CO2 molecules which originally absorbed the initial IR emitted from earth. This, in theory, warms the earth, as energy is held within the atmosphere longer before being lost to space.
Good description, but....
There's no reason that the warmer CO2 can't also warm up the surrounding oxygen and nitrogen molecules (through contact... -loss of vibrational energy), is there?
...off to study now; thanks again!
~samwise
