[Psitticine]

I'm no climatologist, but one thing I know is that many other factors play into climatic effects and seasonal shift.

For example, the warm Gulf Stream flows past Ireland and keeps it warmer than it would be otherwise. On the other hand, the jet stream flowing over the Northern US sometimes pulls down colder air from further north when it goes in the right pattern (AKA the "Siberian Express") and cools down those areas quite a bit.

Just a hopefully interesting side-note . . .