As far as North America goes, while I can't speak for Canada, I know the US is wholly unprepared for massive migration from other regions. Look at how we view i

As far as North America goes, while I can't speak for Canada, I know the US is wholly unprepared for massive migration from other regions. Look at how we view immigrants right now. The last administration's brand was "build a wall and keep them out". These are just the people who are running from oppressive governments or cartels - when global climate change makes the equatorial regions less and less inhabitable from pure heat, apocalyptic storms, desertification, severe humidity, etc. all of Central America is headed northward towards the US and Canada, or south towards Argentina and southern Chile. Admittedly, we're only going to be dealing with 550 million people being added to our combined 360 million people, as compared to Northern Asia and Europe, which will be dealing with literally the rest of the human species. The first wave is going to be all the pacific islanders looking to move when the fish stocks collapse in the 2050s to places like China, Japan, and Australia (while it hasn't completely overheated yet). The next two centuries are going to suck unless we actually do something about it. Presumably after that we'll have taken so much of a beating that some new equilibrium will have been achieved.