But it's basically everywhere the same, and the huge problem is that changes mean some people lose, some might win.
Now as Chris has observed dealing with climate change would have been so much easier 40 years ago (you know when our generations were the school kids), and here I have to disagree a bit with the OP: "Humanity" knew 40 years ago that it would make sense to address the issue ASAP.
But while "dealing" proactively with climate change is almost certainly the sensible, cheaper solution