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m31td0wn t1_j0l8gl9 wrote

Reply to comment by [deleted] in How does high humidity affect perceived temperature in hot and cold environments? by MindTheReddit

That's just evaporative cooling, same as sweating. Although it is possible to cool the air by increasing relative humidity--that's how "swamp coolers" work. Basically humidifiers that spray a fine mist of water into the air, which in extremely arid environments evaporates quickly and lowers air temperature by raising relative humidity. It takes energy for water to phase shift from a liquid to a gas, and that energy comes directly out of the air it evaporates into.

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[deleted] t1_j0lhpn1 wrote

[deleted]

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m31td0wn t1_j0lo7hj wrote

Haha well temperature is just kinetic energy of molecules. Picture the atmosphere as a giant bag of marbles being shaken around. The faster it's being shaken, the more heat it contains. But if you add more marbles to the air, it becomes heavier, and harder to shake. So the shaking slows down. Keep adding more marbles, it's heavier and heavier, so it gets shaken slower and slower.

Not a perfect analogy but I think it gets the job done. The energy required to turn water into a gas is drawn out of the air, causing the air to lower in temperature.

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kilotesla t1_j0lvkj4 wrote

I think a better (but still sloppy and qualitative) analogy is that if the marbles bouncing around hit a layer of stationary marbles held together with pudding, and they knock loose some more marbles when they hit, that process will absorb use up some of their kinetic energy.

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