>Our survey of the climate record from station data reveals many global TW exceedances of 31° and 33°C and two stations that have already reported multiple daily maximum TW values above 35°C. These conditions, nearing or beyond prolonged human physiological tolerance, have mostly occurred only for 1- to 2-hours’ duration (fig. S2).
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>Steep and statistically significant upward trends in extreme TW frequency (exceedances of 27°, 29°, 31°, and 33°C) and magnitude are present across weather stations globally (Fig. 2). Each frequency trend represents more than a doubling of occurrences of the corresponding threshold between 1979 and 2017.
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>The southern Persian Gulf shoreline and northern South Asia are home to millions of people, situating them on the front lines of exposure to TW extremes at the edge of and outside the range of natural variability in which our physiology evolved (36).
I feel like air conditioning millions (and soon, billions) of people will be more than a rounding error of GNP. Indeed, economic activity may be... slightly curtailed... in countries where going outside results in death.
there is a lot more land in the northern hemisphere than at the equator. People will move over the next hundred years. Populations will look much more different in 2100 just like they looked very different in 1900. Countries like Canada will become more than 90 km in vertical length. Countries like Russia and Norway and Finland and the United States will also become more habitable. There is a lot more land that will become accessible than land that will become too harsh.
People are moving because of climate right now and it's causing massive civil unrest. This is nothing compared to the scale that will happen when a sizeable portion of the earth is not inhabitable.
If we get to 6C, which is a very real possibility given the fairly large number of positive feedback and history of rapid climate events on the planet, human extinction is a potential outcome.
But I suspect that's really no evidence or argument that would convince you that things won't be pretty much fine, which is why I'm personally more convinced then ever that we will likely see that 6C.
I'm not saying that things are pretty much fine. Climate change is a real problem. It is a global problem. I can't think of a reason to believe that prevention is a strategy that will work. Adaption on the other hand is likely to be the better option.
What you say is entirely correct: in 2120 there will, proportionally, be more people living in northern latitudes.
It nimbly skips over what will happen to get them there. India is the second most populated country in the world. Pakistan is fifth. Between them, they need to move hundreds of millions of people before the end of the century.
Directly north of them are China and Russia. China and Russia both have very restrictive immigration policies, and are one-party authoritarian states.
Pakistan's average temperature is 60-70f. They are not under threat from heat rise predicted by the IPCC. A good part of India is also moderate in temperature. Like I said earlier, most people already don't live in areas that will become too harsh. The equator is sparsely populated relative to other latitudes.
>Our survey of the climate record from station data reveals many global TW exceedances of 31° and 33°C and two stations that have already reported multiple daily maximum TW values above 35°C. These conditions, nearing or beyond prolonged human physiological tolerance, have mostly occurred only for 1- to 2-hours’ duration (fig. S2).
[...]
>Steep and statistically significant upward trends in extreme TW frequency (exceedances of 27°, 29°, 31°, and 33°C) and magnitude are present across weather stations globally (Fig. 2). Each frequency trend represents more than a doubling of occurrences of the corresponding threshold between 1979 and 2017.
[...]
>The southern Persian Gulf shoreline and northern South Asia are home to millions of people, situating them on the front lines of exposure to TW extremes at the edge of and outside the range of natural variability in which our physiology evolved (36).
I feel like air conditioning millions (and soon, billions) of people will be more than a rounding error of GNP. Indeed, economic activity may be... slightly curtailed... in countries where going outside results in death.