Oh, I know that. My point is that, contrary to what the comment I was responding to said, rich people in western world will not be moving anywhere. Rich Africans will indeed try to move to Europe/North America, but they already do, and would do so even without global warming happening.
So, about 1 billion people out of about 8 billion worldwide. Half of that if you were speaking of "western world" only.
Now imagine what the rest will do. And how that will impact globalized economy on which welfare of western world is built.