PBS: More Areas Too Hot to Work, Too Hot to Live
May 12, 2023
Finally – a good explanation of “wet bulb” temperatures. “It’s not the heat, it’s the humidity” is a real thing, and critical for human well being.
This is not something where you can just “tough it out” – heat stress will kill you – and it’s becoming more common.
Climate Denial Crock of the Week 
May 12, 2023 at 12:58 pm
A significantly underappreciated danger. The temperatures spoken of are for healthy people at low level of activity, not for those doing hard physical work.
A 28C swimming pool is fine to play in, but way to hot to start chucking laps. Some of the waters off Oaxaca Mexico are currently 31C, heat stress could be a real problem if you swam too far from your boat.
May 12, 2023 at 7:08 pm
“Some of the waters off Oaxaca Mexico are currently 31C, heat stress could be a real problem if you swam too far from your boat.”
Water temps below normal body temp (37°C) can still help you shed a lot of heat.
At sea the issue is (especially with hurricanes) how deep the warm water is, rather than just the commonly reported sea surface temperature. Stalled tropical cyclones can still retain great power if they’re over a deep layer of warm water (like the deadly Freddy between Mozambique and Madagascar).
May 13, 2023 at 5:13 am
Not good for fish – higher temperatures means the water can hold less oxygen. Less CO2, as well, so that’s yet another positive feedback.
May 12, 2023 at 7:13 pm
Heat stress can be more of a problem with athletes who train themselves to ignore their bodies’ “slow down” signals, as with marathoners.
That probably applies to field workers that are economically pressured to work long hours in nasty conditions for the income, breaking through “the wall” when their bodies tell them to stop.
😦