(December 17, 2009 at 6:31 am)lilphil1989 Wrote: Well, carbon dioxide reflects a portion of the earth's ~blackbody radiation back at it, keeping it out of thermal equilibrium with the space around. Lots of gases do this, it's the reason the earth's temperature is ~300K and not ~3K like it's surroundings. Increasing the amount of carbon dioxide in the atmosphere decreases the earth's radiation losses, making it warmer.
As far as the basic science is concerned there's not really much to argue against, it's quite simple (indeed Lord Rayleigh hypothesised that increasing greenhouse gases would cause an increase in global temperature, and he died in 1919).
The problem is that it's not readily apparent that the earth is warming, due to the complexity of the earth's climate (solar cycle, el nino oscillations etc).
Which leads to "it's colder this summer than last summer => the earth isn't warming" style arguments.
And it's difficult to predict the future of the climate in a fluid mechanical formalism, because the Navier-Stokes equations are bloody hard to work with.
Actually CO2 absorbs heat and begins to vibrate. The CO2 molecules will eventually emit the energy and stop vibrating. What you described sounds like CO2 is reflecting heat like a mirror reflects sun light, but the CO2 is actually absorbing heat and keeping it within the atmosphere. When the heat is released it is usually absorbed by another greenhouse gas.
