Here in the USA and Europe we have access to Air Conditioning if it gets very HOT. But many areas in Asia and Africa poor people will not have Air Conditioning. It is a Scientific fact that a human being in temperatures over 100 degrees Farenheit for more than a week will definitely die.
Of course if everyone in the USA cranks up their AC we will have power failures and people will die if the temperature is over 100 for a sustained time.

I am only 4 metres above sea level at best, may sound a lot, but in a severe flood and high tide, the water is across the road from me. I am working on assisted migration, trying to help some species move to cooler areas or driers areas if they need to. Far from easy and you can't be reckless and upset a new eco system.

My daughter bought me two new sweaters to help me cope with climate change.

Coupled with population growth, increasing cost of living, automation and food source changes, humanity will probably look vastly different in a hundred years. Perhaps circular or hexagon shaped city hubs that connect may even look like a hive from space. But of course the whole focus of that will be creating a much more efficient means of transportation and product availability. Each cell within this hive might solely produce certain goods or services of their own with the center being the main focus. But with fossil fuels being a finite source I can imagine much will have to change whether people will it or not. I also can imagine areas like Colorado will become prime real estate places for the fortunate few.