L
lynnvinc
Guest
Here’s another RealClimate comment about CO2 and it being heavier than CH4 & thus falling from the sky more:
Actually, I have seen this ill-informed opinion before. To me, it just illustrates that a little knowledge can be dangerous. Others have explained it well enough, but I thought a picture or two might help get the point across.
Easy counter: Measurements show that CO2 does not vary much with altitude; how can you reconcile that with your idea that its molecular weight causes it to sink?
“The observed CO2 concentration is generally high in low altitude and low in high altitude. High CO2 concentration relative to the average CO2 distribution is sometimes observed during the flights. Its difference is about 8 ppmv at most.”
adsabs.harvard.edu//abs/2002AGUFM.A62B0151W
The first part actually agrees with the other guy, but 8 ppm/400 ppm is well within my definition of ‘not much’ (2% over the entire measurement range), and that is the maximum difference they found.
For perspective, look at figure 6.1 at
heliosat3.de/e-learning/remote-sensing/Lec6.pdf
or
spectralcalc.com/atmosphere_browser/atmosphere.php
(Pick CO2, H2O, and CH4 as species.)
Comment by Chris G
Hope this helps.
Actually, I have seen this ill-informed opinion before. To me, it just illustrates that a little knowledge can be dangerous. Others have explained it well enough, but I thought a picture or two might help get the point across.
Easy counter: Measurements show that CO2 does not vary much with altitude; how can you reconcile that with your idea that its molecular weight causes it to sink?
“The observed CO2 concentration is generally high in low altitude and low in high altitude. High CO2 concentration relative to the average CO2 distribution is sometimes observed during the flights. Its difference is about 8 ppmv at most.”
adsabs.harvard.edu//abs/2002AGUFM.A62B0151W
The first part actually agrees with the other guy, but 8 ppm/400 ppm is well within my definition of ‘not much’ (2% over the entire measurement range), and that is the maximum difference they found.
For perspective, look at figure 6.1 at
heliosat3.de/e-learning/remote-sensing/Lec6.pdf
or
spectralcalc.com/atmosphere_browser/atmosphere.php
(Pick CO2, H2O, and CH4 as species.)
Comment by Chris G
Hope this helps.