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

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

#381

Post by exo-pla-net »

giantg2 wrote: post #376
exo-pla-net wrote: post #366

Earlier quoted context omitted.

You come off as browbeating him, accusing him of not knowing things, when he said a small thing that was fully accurate if not precise. That's why you're being downvoted.

"I’m inclined to say that this is not very survivable, regardless of your precautions, if your air conditioning has died." How is that fully accurate? It seems to me that "not very survivable" is not accurate and is an over exaggeration. I don't expect a 50% death rate, even 10% would be extremely generous. It would be like me saying linux desktops are very common.

This is silly/pedantic. He's talking about being in a typical house with a dead A/C, experiencing the equivalent of 70C. Please tell us how you're going to survive that circumstance. Answer: you're not. You're going to change your circumstance, since it's not very survivable. You're going to leave your house and try to find somewhere cooler. His statement is accurate if not precise.

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

#382

Post by Aeolun »

lmilcin wrote: post #234
Aeolun wrote: post #227

Earlier quoted context omitted.

> going into cellar. The air will get cooler but the humidity will rise. If we are already counting on a wet bulb temperature of 35C, the humidity is likely already very close to 100%. Reducing the temperature is likely to be a net good.

That's false. TLDR: The air gets cooler but still can't cool you. Your body produces heat that has nowhere to go and you still die. Then the walls of the cellar heat up immediately, because cooling 100% humid air requires sinking a lot of energy. If you found yourself in conditions of an actual heat wave as described, you would despair at the fact the air can get cooler in your cellar but it doesn't cool you at all.…

> TLDR: The air gets cooler but still can't cool you.

Evaporative cooling is not the only kind of cooling that exists.

If this were the case you’d die of heat death standing in the middle of 100% humidity antarctica.

If your cellar is cold enough you’ll be in a much better situation than before. You seem to assume that the moment you open your cellar door, all humidity and temperature will immediately equalize with the outside.

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

#383

Post by lmilcin »

Aeolun wrote: post #382
lmilcin wrote: post #234

Earlier quoted context omitted.

That's false. TLDR: The air gets cooler but still can't cool you. Your body produces heat that has nowhere to go and you still die. Then the walls of the cellar heat up immediately, because cooling 100% humid air requires sinking a lot of energy. If you found yourself in conditions of an actual heat wave as described, you would despair at the fact the air can get cooler in your cellar but it doesn't cool you at all.…

> TLDR: The air gets cooler but still can't cool you. Evaporative cooling is not the only kind of cooling that exists. If this were the case you’d die of heat death standing in the middle of 100% humidity antarctica. If your cellar is cold enough you’ll be in a much better situation than before. You seem to assume that the moment you open your cellar door, all humidity and temperature will immediately equalize with t…

Again, completely wrong. 100% humid 0C air is still 0C wet bulb temperature -- perfectly good for cooling you down.

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

#384

Post by giantg2 »

exo-pla-net wrote: post #381
giantg2 wrote: post #376

Earlier quoted context omitted.

"I’m inclined to say that this is not very survivable, regardless of your precautions, if your air conditioning has died." How is that fully accurate? It seems to me that "not very survivable" is not accurate and is an over exaggeration. I don't expect a 50% death rate, even 10% would be extremely generous. It would be like me saying linux desktops are very common.

This is silly/pedantic. He's talking about being in a typical house with a dead A/C, experiencing the equivalent of 70C. Please tell us how you're going to survive that circumstance. Answer: you're not. You're going to change your circumstance, since it's not very survivable . You're going to leave your house and try to find somewhere cooler. His statement is accurate if not precise.

Lol it is not the equivalent of 70C. Please see the other resources people have posted here about understanding wet bulb temperatures. Even a wet bulb of 35C can be tolerated by most for hours - 70C could not.

I would not leave my house. My house has insulation and thermal mass, which would delay the tempature from reaching that level until later. I could use water to cool myself, whether in the bath tub or a trashcan. I could use a fan if there's power (depends on the temperature and humidity to reach that wet bulb). I could use frozen objects (even without power, the freezer will stay cold for at least a day). I also have a generator to power these things if there's a short to medium term outage.

Their statement was not about changing one's circumstance. It was that even with precautions, it's not very survivable. This is neither accurate nor precise. It is very survivable with precautions.

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

#385

Post by France_is_bacon »

jiggawatts wrote: post #143
boplicity wrote: post #2

Kim Stanley Robinson's recent book The Ministry For the Future starts with a very disturbing scenario: A heatwave with a "web bulb" temperature of 35 Celsius. It turns out, in those temperatures, even young and healthy people can't survive. Combined with power outages, as happens in the book, everyone living under such a heat wave will likely die. It's looking increasingly likely that such heatwaves are possible in t…

> Combined with power outages, as happens in the book, everyone living under such a heat wave will likely die. That's an exaggeration. Extreme heat (including heat waves that exceed this threshold) happen semi-regularly, and the death rate when they occur is nowhere near 100%. More like 0.1% or less. Electrically-powered air conditioning is not the only way to cool a human body. Simply escaping to an underground or s…

Huh. Glad to read what you wrote. I trust you over actual scientists, because you wrote it so well in a short few sentences. Thanks for the info!

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

#387

Post by N1H1L »

goatlover wrote: post #305
rstuart4133 wrote: post #200

Earlier quoted context omitted.

> Extreme heat (including heat waves that exceed this threshold) happen semi-regularly The threshold is wet bulb 35 for 7 hours. That is when fit young humans can't survive. Older people die well before that of course. And no, it doesn't happen regularly. I wasn't aware it had happened at all, although others here say it has. But it has come close. From https://www.telegraph.co.uk/global-health/climate-and-people...…

What city doesn't have running water?

Lots. Many cities have running water for only a few hours a day.

And there may often be only one tap per 100 people in densely populated slums.

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

#388

Post by N1H1L »

rini17 wrote: post #165
jiggawatts wrote: post #143

Earlier quoted context omitted.

> Combined with power outages, as happens in the book, everyone living under such a heat wave will likely die. That's an exaggeration. Extreme heat (including heat waves that exceed this threshold) happen semi-regularly, and the death rate when they occur is nowhere near 100%. More like 0.1% or less. Electrically-powered air conditioning is not the only way to cool a human body. Simply escaping to an underground or s…

Many apartments don't have a bathtub, only a shower. And if everyone keeps tap water running, the pressure will drop down to trickle. Cold cellars can be in short supply, underground car parks tend to get hot too. And seems you probably never bathed in 35°C water, it's definitely not refreshing. And there are psychological issues that people just don't know what to do till it's too late. I was living an apartment wit…

True. Which is why what always puzzles me is that cities like Austin or Phoenix are gaining population. It's so hot there!

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

#389

Post by mrpopo »

briantakita wrote: post #355
mrpopo wrote: post #288

Earlier quoted context omitted.

No. IPCC 6th assessment report, summary for policymakers, page 8/42. Read it. IPCC is the most conservative science body ever created. It comprises hundreds of scientists from all over the world, including Saudi Arabia and others, who need to unanimously approve each sentence. The role of human emissions in the current warming has been assessed without any possible doubt.

The IPCC is focusing on sensationalist & self-admitted "unlikely" models in their editorials. It's not even the majority view of the models that are being trumped up. Sensation sells. Money talks. The role of human emissions as the key driver of climate change has plenty of doubt & plenty of money involved pushing a pre-determined outcome with the purpose of imposing taxes & centralizing power. In the meantime, human…

No one discusses IPCC reports. It came out this week, and was discussed at most 10 min per day on major news channels.

IPCC scientists are volunteering for the report, they are not wealthy. They are literally spending their own free time and money writing thousand-pages long reports.

You just choose not to believe the most rational answer because it's inconvenient.

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

#390

Post by jobigoud »

goatlover wrote: post #305
rstuart4133 wrote: post #200

Earlier quoted context omitted.

> Extreme heat (including heat waves that exceed this threshold) happen semi-regularly The threshold is wet bulb 35 for 7 hours. That is when fit young humans can't survive. Older people die well before that of course. And no, it doesn't happen regularly. I wasn't aware it had happened at all, although others here say it has. But it has come close. From https://www.telegraph.co.uk/global-health/climate-and-people...…

What city doesn't have running water?

Many cities I would think. My spanish teacher lives in a big city in Venezuela and they use water tanks and electricity is rationed.
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