Real quickly,
You point out,
You are incorrect when you say that, "CO2's having the largest effect." CO2 does not have the largest effect. Water vapour has that honour....
However, with the rest of the sentence, "and it is the easiest to change," then water vapor drops out of the running for GHG's to be "singled out."
But yes, good catch; it is a poorly written sentence. The answer to 'why we should single CO2 out' should have been, '....of the GHG's that are easy to change, CO2 is having the largest effect'
Next you asked about,
(Why did you put 'increases heat on earth' in quotes?)
I was just reusing the phrasing of that website that I had quoted (from directly above) talking about nitrogen, oxygen, and CO2. It wasn't meant as sarcasm, or anything sinister.
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That is a neat link Canuk provided. It's all a documented opinion piece, but it's gotta be over 90% "spot on," and much more detailed with depth, than most sites have when talking about "the greenhouse effect." It's the best I've seen, except maybe for these science fora.
Molecules that absorb UV and visible light (and shorter wavelengths) are what can increase the heat of the earth. Looking at Canuck's link, the O2/O3 molecules will absorb UV rays allowing that energy to be converted to infrared heat through collisions with cooler molecules.
The absorption of IR radiation does not increase the heat on earth. It slightly slows rate at which the IR heat can escape.
I agree, what we're talking about is the heat radiated away from the earth (whatever the higher energy, shorter wavelength source originally was).
...and it seems the correct wavelength should be about 3; and not 4-5, like I've been saying (based on reading a low-res. graph), though that's something that needs checking because the "4-100 micron" figure for "heat" is from the same graph.
...another good catch... more later.
But I have to ask about how, slowing the "rate at which the IR heat can escape" "does not increase the heat on earth," unless you're using different definitions for "heat."
I suppose the answer is, "That increases the chances of it being reduced to a longer and less energetic wavelength, but it does not cause more heat;" but I think there is room for more understanding here.
... and also for the rest, about concentrations and wavelengths; I need to look long, and think about this before a better reply.
~be back later
