I'm aware. The question is why.
The sun does seem to work in the same way as our own,Magicka when not bent by Mortals is pure energy.
Maybe the Et'Eda who make up nirn of certain areas affect who the magicka affects one region to the next,The ones near Skyrim,High Rock and Atmora are more inclined towards frost while the ones in Cyrodill,Black Marsh and Alinor are more inclined towards fire.
Also this
The Gods in the TES universe are bat [censored] crazy..Thats why.