I think about this once in a while too, and then I remember that a bunch of German Nazis came out of the woodwork when just a million Syrians were admitted as war refugees. Whether northern countries accept more people or not, migration out of the tropics due to uninhabitable climate is coming.
Until the heat is everywhere and there is no place to run to, at which point things get ugly real fast.
I'm still for helping those in need, we have the resources to make a whole lot of lives better here.
Europe will see a massiv increase in migration in the near future. That will further push Europe to the right. At some point in the future Europe will try to become a fortress, denying entry to anybody to secure the resources that are left by floods and droughts at all costs. I fear that this is at least a possible outcome and I fear the kind of political climate that will come with this, not the least because the right wing has historically blocked efforts to stop climate change.