Why is CO2 blamed for global warming when it has low heat capacity and low concentration in the atmosphere while water vapor, with much higher concentration and much higher heat capacity is the real cause?

https://www.quora.com/Why-is-CO2-blamed-for-global-warming-when-it-has-low-heat-capacity-and-low-concentration-in-the-atmosphere-while-water-vapor-with-much-higher-concentration-and-much-higher-heat-capacity-is-the-real-cause

https://www.quora.com/Why-is-CO2-blamed-for-global-warming-when-it-has-low-heat-capacity-and-low-concentration-in-the-atmosphere-while-water-vapor-with-much-higher-concentration-and-much-higher-heat-capacity-is-the-real-cause/answer/TL-Winslow

My reply:

Why? Look up the words hoax and scam. CO2 physically can’t warm the Earth’s surface because only the Sun does that. CO2 is a trace element of the atmosphere, which cools the surface, taking surface heat up into outer space while dissipating it along the way. Take a hot air balloon for example. Like the air itself, it contains 0.04% CO2. After release from the surface, it begins rising, converting its heat to work to rise against the atmosphere’s gravity field. Eventually it loses all its heat and quits rising and starts sinking. Where did the heat go? It was converted to work.
The greenhouse warming hoaxers want you to believe that if the CO2 in the balloon absorbs some infrared from the surface on the way up, it will turn into a dragon in the sky that sends the heat back down somehow, reheating the surface. This is moose hockey because at 0.04% of the total, any CO2 molecules that absorb any radiation will heat up and start moving faster, soon bumping into the neighboring molecules and losing the heat. Meanwhile the balloon keeps rising, draining all the heat to create work and fight gravity. The net effect is zilcho heating of the surface.
Try filling a balloon with pure CO2 and tethering it while heating it with a space heater, then measure the IR radiated 50 ft. away. I’ll bet it’s zilcho. It’s all a huge hoax.
As to water vapor, it has a way of reaching a max height and still retaining heat. If it absorbs more from surface IR, that doesn’t change anything. At the end all it can do is release precipitation (rain, hail snow), which cools the surface and can’t warm it. That’s because to rise that high it lost so much heat it’s way cooler than the surface. Look up lapse rate and see the truth that global warming has an insurmountable hurdle in the sky.
Here’s my complete explanation for the general public of why the CO2 greenhouse warming theory is a hoax, which is so devastating that nobody can refute it, only play ostrich and ignore it and hope nobody else reads it. Take this opportunity now. The truth is out thre.
TLW's Two Cents Worth on Climate Change