I am creating a board game that requires an underground cavern world, with huge pipes that pump air for the civilization living there. The underground region is at about 35-40 degrees north latitude. I am wondering what sort of climate such a region would have. Is it really just no weather?
I am thinking that there will be convection from the air pumps, and if the ceiling is high enough, clouds of mist might form if it is humid enough. There will probably be bio-luminescent organisms, or rat-like creatures. The climate will be relatively cold for its latitude; because there is no sunlight, the only sources of heat will be the giant air pumps.
Does anyone have a similar logic for the climate, or is it different from what I thought?