Yes, it does have it by default - player slowly heating up on the sun/surface, and cools down underground and during night. (How hot is the Atum's desert, actually? Maybe needs to increase heating rates... by a lot)

But, unfortunately, Atum's clothes does not provide you with heat resistance/immunity like TaN's jelly armor from the TaN itself. Any way to add compat? I'm pretty sure you can, concidering that you slammed TC aspects into the mod.

Closing, since armor can be added in the TaN config. According to what @Carvercarver1 said on Discord