What happens when the nitrogen goes up

CO2 is heavier than air. How can it rise to the upper atmosphere and increase the greenhouse effect?

It is correct: CO2 is heavier than air. Air is a mixture of gases. It only consists of a tiny fraction of carbon dioxide, while 99 percent consists of nitrogen and oxygen, both of which are much lighter than CO2. If you look at air as a gas mixture and compare it with pure CO2, then the CO2 is actually about 50 percent heavier or physically correct: denser.

Does that mean it sinks to the ground?

No. That would only happen if the air were a standing mass in which the heavy CO2 molecules would comfortably sink down. But then we would also have a big problem. Because if the air were a standing mass, we would suffocate in exhaust gases. And if all the CO2 from the atmosphere were to sink to the ground, even more so. But that's not how it is. But the air moves up and down. There is wind and turbulence. Warm air warms up on the ground and rises. It happens every day.

The many CO2 particles in the air have absolutely no time to slowly settle and accumulate on the ground, because the air masses are constantly being whirled up by wind and weather and are thus distributed over the atmosphere. This has often been measured and the result is: The proportion of CO2 molecules in the air is almost constant up to a height of almost 100 kilometers. There is no “enrichment” on the ground, no matter how plausible it may sound.

But if it were to accumulate at the bottom, would the argument be correct?

No, not even then. Because the argument says yes that CO2 has to rise in order to develop the greenhouse effect. That is also wrong. The term greenhouse effect may be misleading. It sounds a bit like the CO2 is forming a kind of roof somewhere above us - like the glass roof in a greenhouse. But the greenhouse effect begins in some cases directly above the earth's surface, as gases such as CO2, methane and water vapor simply absorb the heat radiation from the earth and some of this heat is radiated back to the earth's surface. In order to develop this effect, the CO2 would not have to rise at all. Nevertheless it gets into the upper atmosphere and there it develops an additional effect.

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