Well it's about temperature differences, those are larger in winter I guess. On the other hand there is a lot more radiative heat load in summer...
Murca
Tbh I don't see where this is bad (except maybe the 0 label). Why should "up" always be "better"? There are countless other examples where this is not the case. Or am I missing something here?
Ich glaub du bist da was ganz heißem auf der Spur https://de.wikipedia.org/wiki/Mem
Well it's about temperature differences, those are larger in winter I guess. On the other hand there is a lot more radiative heat load in summer...