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One of the two sources of Earth's heat is primordial heat, which is the product of gravitational compression and impacts during Earth's formation. My understanding is that work is done on the core, leading to compression, and this increases internal energy/temperature. Does anyone know what role gravitational compression plays in the atmosphere with regards to temperature? The pressure at sea-level is the result of gravitational compression. Does gravitational compression raise the temperature of the denser layers of the atmosphere in any way, or is the only heat input from surface conduction, radiation and convection?

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Both the mass of the atmosphere and the radial extent available to it are small by comparison the the total mass and radial extent, so you can immediately expect a small contribution. –  dmckee Feb 22 at 22:33
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Are you asking if the air near the surface is kept warm by gravity? Because virial heating from gravity is a one-time thing - once the contraction stops, no further heating occurs. –  Chris White Feb 22 at 22:38

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The atmosphere is more or less at equilibrium with regards to being compressed by gravity, so there is no atmospheric heating caused by gravity (otherwise the atmosphere would gradually get closer and closer to the Earth, which clearly is not the case).

Heating of the atmosphere is almost entirely due to radiant energy from the sun, along with terrestrial heat sources.

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I think the temperature profile of the atmosphere actually approaches the adiabatic gradient. You are correct that solar is the source of heat, but due to convection, the source is not the only cause. –  Mark Rovetta Feb 22 at 23:08

Atmospheric pressure, at some altitude, is largely due to the weight of the atmosphere above that altitude. The atmosphere also virtually behaves like an ideal gas. If evaporation of liquid water increases the concentration of H2O molecules in the air the density decreases and the air becomes buoyant and rises. As it rises it expands and cools. Rising air can displace air at altitude downwards. This air becomes compressed and warmer.

You might want to take a look at one of the standard atmospheric models

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Thank you. That's adiabatic expansion and contraction right? I'll certainly check those models out. –  Seanosapien Mar 4 at 17:04

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