CO2 Has a Very Minor Role in the Atmosphere
https://www.windtaskforce.org/profiles/blogs/co2-has-a-very-minor-role-in-the-atmosphere
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In the tropics and subtropics, CO2 a weak photon absorber, plays no measurable role, because, near the surface, it is outnumbered by about 27400/420 = 65 to 1 by water vapor, WV, a strong photon absorber.
Plus, WV, 18, is lighter than CO2, 44, and air, 29, so it rises and condenses into clouds at about 2000 meter elevation.
The clouds, with prevailing winds, are transported to northern latitudes, to areas underserved by the sun, especially during winter.
That means the WV and clouds we see up north, from the 37th parallel upwards, come from faraway places, because up north there is not enough energy to evaporate much water. 
Any evaporation is from near or on the ground, such as from as dew, ground fog, snow and ice.
But, even up north, near the surface, CO2 plays no measurable role, because WV outnumbers CO2 by about 17700/420 = 42 to 1.
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Above the Clouds
CO2 begins to play a measurable role when the presence of WV is lower, say 3 to 1, at about 3000 m elevation, which is above the clouds. WV freezes on all dry air molecules and on CO2, pollen, aerosols, etc. 
Any sunlight photons are reflected, refracted. The some of the photons will be absorbed by the frozen WV molecules. Photons will not absorbed by the CO2 molecules, because they are covered with ice. 
The thermal effect of that absorption is miniscule, compared to the absorption near the earth surface.
The atmosphere heat content, aka Enthalpy, is 358 kJ / m^3 near the surface, decreases to 19.5 KJ / m^3 at 20 km.
https://www.windtaskforce.org/profiles/blogs/natural-forces-cause-periodic-global-warming
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At colder temperatures above the clouds, any emitted photons would have longer wavelengths beyond the CO2 15 micrometer absorption window. However, WV would absorb these photons, because it has a much wider window starting at about 15 micrometer. 
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NOTE: A photon, a vibrating package of energy with a wavelength, has no mass, moves at the speed of light in a vacuum, which is many orders of magnitude greater than the speed of molecules
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At higher elevation, temperature is less, density is less, there are fewer molecules/m^3 or moles/m^3, there are fewer collisions, because molecules are further apart. 
The average kinetic energy of molecules decreases with temperature. See URL
KE = 3/2 RT = 3/2 x 8.314 J / (mol K)
https://courses.lumenlearning.com/suny-albany-chemistry/chapter/the-kinetic-molecular-theory/#:~:text=Key%20Concepts%20and%20Summary,the%20mass%20of%20its%20molecules