I think some of you underestimate the human race ability to survive.
Did you know that Barrow Alaska has been habituated for about 1,500 years now? With temperatures cloaking at -50f before the wind chill? Average rain around 4.5"? 2 months of perpetual night in the winter?
What the future holds is that the standard of living on industrialized nations is not sustainable, so I would expect that it would continue to drop. In that drop the people on top will do their best to manage said drop in the standard of living as best as they can, so they can continue to manage the greatest engine for resource extraction and enrichment of the 1% the world has ever seen. When that tower of cards eventually falls down then you get civil unrest followed by war, as before and as will be after.
And also guess what; a good chunk of the world’s population will not even notice. The world’s largest refugee camp is Kutupalong in Bangladesh, home of 500,000 souls. Some of them has been lost in there in limbo for about 20 years.
But count your blessings; even in declining standards of living, civil unrest, and war, you are much better off where you are now than there.