Elf Yome to Hajimeru Isekai Ryoushu Seikatsu - Vol. 2 Ch. 9 - Spirit magic

[MangaDex]

 

[AbuHajaar]

If shit was evaporating in an enclosed space, wouldn't the air pressure INCREASE?

 

[RakuraiSenshi]

If shit was evaporating in an enclosed space, wouldn't the air pressure INCREASE?

I think so. Evaporation would mean more gas. Ears popping I think suggests they do mean a drop in air pressure. From the diagram when they mentioned evaporation, maybe they meant condensation. Also, were they trying to increase the temperature or something? I suppose a temperature increase would lead to evaporation, but did they mean the spirits used evaporation to increase the temperature?

I might be wrong on various points.

 

[Chrisis]

most likely meant that it was evaporating outside of the tent perhaps

 

[b33fy]

Evaporative cooling trades the enthalpy of a liquid to transition to it to a gaseous phase, lowering the temperature (this doesn't break the 2nd law of thermodynamics because gases have more entropy / are more chaotic / are less orderly than liquids). Which would increase the pressure. Any change in pressure would be short lived; flexible, leaky containers like a tent make for terrible pressure vessels, and there's miles of air above them weighing down on them. I don't get the impression that technical details are this series' strong point, much as it may want them to be.

 

[Morsealworth]

Also, wouldn't it been cheaper MP-wise to just divert the typhoon by changing the air currents a little? I mean, the winds are normally very stable and just adding/removing a little pressure would change a lot.