Millions of people may have to adapt. Fortunately, people are good at that.
https://www.theguardian.com/science/2022/jul/31/why-you-need...
People can survive amazingly hot temperatures, as long as they can sweat - once the wet bulb temp gets far above 31c people are in trouble - the theoretical maximum is 35c.
We won't hit these wet bulb temps in places like the US or even much of Europe, but built up China, India etc are at risk of approaching these in our lifetimes, potentially far sooner.
> Concern often centres on the “threshold” or “critical” WBT for humans, the point at which a healthy person could survive for only six hours. This is usually considered to be 35C, approximately equivalent to an air temperature of 40C with a relative humidity of 75%. (At the UK’s 19 July peak temperature, relative humidity was approximately 25% and the wet-bulb temperature about 25C.)
(WBT is Wet Bulb Temperature)
Yes, I read that people have been living for 100s of years (pre-AC) through temps regularly hitting 46 degrees, but see also the response on wet-bulb temps and survivability. 46 degrees for 5 days straight without AC (as in, backup power is gone...) and I think we'll see some losses.
Europe regularly sees large deaths due to heat during summers already today, true mostly in elderly.
Make it a hundred, though, so I can defend it to my dependants better and you're on.
(I realize that even if I win, I lose, but whatever, I'm more interested in talking with someone who has significant hope, enough to put money on the line.)
In my opinion, this reduction in deaths is mostly due to the increasing ability of the developing world to better master their environment, enabled by technological advances powered largely by cheap energy from fossil fuels. If you have alternative explanations, I'm happy to hear it. But as the evidence stands, it would be more delusional to think climate change will cause rampant mass deaths.
[0]: https://library.wmo.int/viewer/57564/download?file=1267_Atla...