The emergence of heat and humidity too severe for human tolerance (2020)

Re:The emergence of heat and humidity too severe for human t... by chinchilla2020 on Wednesday August 11, 2021 @11:27AM (#28143159)

95 Fahrenheit is actually quite survivable. It is dangerous for old people, young people, and the very sick when combined with sun exposure and other factors.

I spent much of my life living in that temperature range without A/C, working outside during the day in the sun.

It's hot but not going to kill you. In fact, there are massive homeless encampments outside my window right now in extremely humid, hot, Texas weather (it is 95-97 all week and very human). The homeless have endured many summers like this.

It is a massive stretch to say these temperatures are not survivable. They are not healthy in the long run - but neither is sun exposure.

It's an incredible exaggeration to say Chicago (where 600 people died in the heat wave) is not survivable at all when millions actually did survive the heat wave without AC.

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Re:The emergence of heat and humidity too severe for human t... by elbasti on Wednesday August 11, 2021 @12:45PM (#28144399)

35 wet-bulb temperature is not survivable. That is not a matter of opinion, it is a fact. Your body generates heat and at that temperature it is unable to shed it through any means and you will die in a couple of hours.

If a major city has such a heatwave, it will almost certainly be a mass casualty event, mitigated only by the duration of the wave and how many people have A/C (or how long the blackouts last).

A fan won't work because your sweat will not evaporate: in fact it just heats you up faster (like breathing on your skin in a sauna).

Such temperatures have only been measured a few times on earth, so no, you have not experienced them.

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Re:The emergence of heat and humidity too severe for human t... by kristjansson on Wednesday August 11, 2021 @12:59PM (#28144591)

N.B. the 35c/95f temperature they're talking about is _not_ air temperature. It's 'wet bulb' temperature, or what the air temperature would be at 100% humidity. Only when the actual humidity is 100% are the two equivalent. Otherwise, the wet-bulb temperature measures the lowest temperature achievable by evaporative cooling. The survivability concerns of sweat being unable to cool humans below hyperthermic levels should be obvious.

At quick check, humidity in Houston is like 55%, so the wet-bulb temperature is only ~80f. Uncomfortably hot, but not close to the threshold discussed in TFA.

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Re:The emergence of heat and humidity too severe for human t... by chinchilla2020 on Wednesday August 11, 2021 @04:14PM (#28147143)

Good to know. I should not have skimmed the article before replying.

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Re:The emergence of heat and humidity too severe for human t... by electroly on Wednesday August 11, 2021 @11:48AM (#28143506)

They're talking about wet bulb 95 degrees which occurs at somewhere around 130 degrees of open air temperature. You have not spent much of your life at wet bulb 95 degrees.

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Re:The emergence of heat and humidity too severe for human t... by spywaregorilla on Wednesday August 11, 2021 @11:48AM (#28143522)

95F in dry air is not the same thing as wet bulb 95F. That is the majority of the discussion being had in other threads.

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Re:The emergence of heat and humidity too severe for human t... by kristjansson on Wednesday August 11, 2021 @01:04PM (#28144660)

Critically, not just 'dry air' vs 'humid' in the human sense. Wet-bulb is temperature at 100% relative humidity. A 'humid' day in the human sense is like 60-70%.

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