One additional big evidence for CO2 greenhouse effect, which is often forgotten, is Venus. Planet Venus, i mean. Venus' athmosphere is entirely made out of CO2, concentration is about 96%. And, we know from direct observations (including probes) that Venus' average surface temperature is much, much higher than one of any other planet in Solar system:
- mean surface temperature, Venus = ~462 degrees C;
- mean surface temperature, Mercury = ~47 degrees C;
- mean surface temperature, Earth = ~15 degrees C;
- mean surface temperature, Mars and other planets = below 0 degrees C.
If this doesn't prove greenhouse effect, then probably nothing would. Especially if one does know, from physics, that amount of energy emitted by any hot body is proportional to FOURTH power of temperature difference between the body and environment - thus that 462 is INSANE thing. In kelvins, Venus has more than 2,5 times higher temperature than other inner planets; 4th power of 2,5 is 39,0625; so Venus is some 40+ times more efficient at holding ("capturing") heat as any other planet of our solar system.