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by Projectiboga 46 days ago
Our bodies won't be able to handle a temperature regime that hot overall. The factor to research is Wet Bulb Temperature Effect. Basically our bodies are like sports cars and keeping our body cool is a challange under high humidity with temperature near our body temp.

https://www.weather.gov/ict/WBGT

https://www.psu.edu/news/research/story/humans-cant-endure-t...

UNIVERSITY PARK, Pa. — As climate change nudges the global temperature higher, there is rising interest in the maximum environmental conditions like heat and humidity to which humans can adapt. New Penn State research found that in humid climates, that temperature may be lower than previously thought.

It has been widely believed that a 35°C wet-bulb temperature (equal to 95°F at 100% humidity or 115°F at 50% humidity) was the maximum a human could endure before they could no longer adequately regulate their body temperature, which would potentially cause heat stroke or death over a prolonged exposure.

Wet-bulb temperature is read by a thermometer with a wet wick over its bulb and is affected by humidity and air movement. It represents a humid temperature at which the air is saturated and holds as much moisture as it can in the form of water vapor; a person’s sweat will not evaporate at that skin temperature.

But in their new study, the researchers found that the actual maximum wet-bulb temperature is lower — about 31°C wet-bulb or 87°F at 100% humidity — even for young, healthy subjects. The temperature for older populations, who are more vulnerable to heat, is likely even lower.

2 comments

> 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.

It's a problem anywhere, just that the dry bulb temperature needed to reach a given wet bulb temperature goes up as humidity goes down.
It's a problem anywhere that temperatures reach that high. Higher latitudes have colder climates. Hence, not a problem. If it becomes a problem, people move toward the poles. No longer a problem.

Earth would have to experience > +35 to +50C for the poles to be uninhabitable due to heat.

> Higher latitudes have colder climates.

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.

Yes, polar regions are reliably colder than equatorial regions. Lytton, BC hit the temperature you cite for one day on Tuesday, June 29, 2021. That's a sign of warming, and we should expect more warm days than in the past at any given lattitude. But it is not evidence against the general case that polar regions have colder climates than equatorial regions.

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...

This explains something about why I haven't understood casually mentioning 40c+ temps, 34c in Hong Kong with no breeze is about as much as I can handle.