> Our bodies won't be able to handle a temperature regime that hot overall. The factor to research is Wet Bulb Temperature Effect.
That's a problem at the Equator, but not at the higher latitudes.
That's a problem at the Equator, but not at the higher latitudes.
Earth would have to experience > +35 to +50C for the poles to be uninhabitable due to heat.
Not reliably, not continually, and much less often when you dump enough energy into the atmosphere to disrupt major wind patterns.
British Columbia hitting 121°F/49.6°C at 50°N latitude would sort of suggest your generalization doesn't hold true anymore.
Here's a citation demonstrating that over the last 95 million years if you need one: https://www.pnas.org/doi/10.1073/pnas.2111332119
One more just for fun: https://journals.ametsoc.org/view/journals/clim/12/4/1520-04...