Well, that's why they changed the theory from "global warming" to "climate change." When your initial guess is proven blatantly incorrect, switch to a hypothesis that can't possibly be wrong!

To think of it another way, when was the last time you read a headline that said, "Temperature Slightly Different Than This Time Last Year"? Oh, wait, that's right. You just read that, because that's the theory of climate change: over time, things won't stay exactly the same. Well, no shit.