And now for a carbonated beverage. With hops?

Have you ever noticed that when people diagram how CO2 does its global warming, they draw a big barrier cloud high over the ground? It sits there like a green house roof letting the sun's energy in, but blocking the heat from escaping.

I wonder how the CO2, which is heavier than air, stays up there. I touched on this before in talking about canaries in coal mines. The further down in a coal mine you go, the higher the risk you have of CO, methane, and CO2 poisoning. Those items are heavier than air, and as such displace the air way down there, thanks to gravity.

So is CO2 a magical one-way mirror that passes IR in, but blocks UV from going out? Of course not! CO2, as with H2O vapor are gases. Both absorb UV in the same limited wavelength range. But there is so little CO2 compared to H2O that we need to talk about fractions of a percent.

H2O vapor and CO2 are UV "sponges" that only absorb UV energy at a very limited frequency. There is more H2O and CO2 UV absorption capacity than UV energy to absorb.

Having more sponges under a faucet does not cause water to be absorbed any faster - especially when you have more sponge capacity than water.

I like to illustrate this with a huge swimming pool into which some dumped 20 gallons of water. The water represents the UV energy that green house gases can absorb. Some of the water goes down the drain. Next we throw in 1000 blue sponges. These sponges represent water vapor. Somewhere in those 1000 sponges is one green sponge. That sponge represents all of the green house gasses. One little corner of that green sponge (difficult to see) has been colored black to represent CO2.

The pool has only 20 gallons of water. Putting in more yellow or black sponges will not change that. While we can increase the heat retention capacity, we are not increasing the amount of heat.

Oh, also don’t let people get away with telling you that all of the CO2 in the water is increasing the acidity of the oceans. Water does not hold CO2 in solution very well. Especially warm water. Especially agitated water. And really especially agitated warm water, like the parts of the oceans that are being said to becoming acidified.

Here is a quick home-based experiment for you. Go get a carbonated beverage from your fridge. Take a taste. Nice and fizzy, right? Now leave it sitting open on your counter for a while. Or put it in the fridge. You can shake it from time to time if you wish. Wait a couple of hours. Take another taste. Fizzy? I didn’t think so.

The axiom to remember: CO2 is a rare trace gas that is essential to our biosphere.