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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)

#291

Post by shoemakersteve »

tootie wrote: post #270
j1elo wrote: post #254

Earlier quoted context omitted.

For people reading "web bulb" here and not having the least idea of what it is, first of all it's "wet bulb", and this article explained it very clearly to me: https://www.iflscience.com/environment/why-is-everybody-talk...

Seems like Wet Bulb is a more precise version of what some weather reporters call "Heat Index". Meant to measure how hot it actually feels on the skin. Is there any sort of formula mapping heat + humidity to wet bulb?

In Canada we call it "humidex" because we're cool like that.

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

#292

Post by tullianus »

hoseja wrote: post #129
blueblisters wrote: post #93

Earlier quoted context omitted.

Radiative cooling roofs, like those from sky cool systems actually cool your house during the day. I'm not sure how cost effective those are but the technology seems to be very promising.

Those radiate through the atmospheric microwave window, right?

Yep! Looks like the authors of the first paper I read on it (glass microspheres in silver-backed clear plastic film) are finally starting to commercialize it too... http://radi-cool.com/technologies/

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

#293

Post by exo-pla-net »

giantg2 wrote: post #245
Aeolun wrote: post #205

Earlier quoted context omitted.

> WB 35 °C (95 °F) – theoretically equivalent to a heat index of 70 °C (160 °F), though the heat index does not go that high I’m inclined to say that this is not very survivable, regardless of your precautions, if your air conditioning has died.

I'm not sure you understand wet bulb and heat index. Heat index is largely irrelevant when talking about the precautions mentioned. The actual temperature is no where near 70C, and actual temperatures matter when talking about cooling that does not use ambient air (and evaporative cooling assuming 100% humidity in this case). A wet bulb of 35C means that there is a thermometer covered with a wet cloth reading that te…

Re-read the comment you're responding to.

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

#294

Post by quantum_solanum »

djrogers wrote: post #285
elchief wrote: post #94

Earlier quoted context omitted.

And people START dying, en masse, at 28C wet bulb (see chicago and vancouver heat waves)

> en masse I'm not sure that phrase means what you think it means... Yes, there were ~600 tragic deaths in BC from the heat dome, but en masse means 'as a whole' or 'as a group', and a .012% death rate does not really qualify there.

shut the fuck up

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

#295

Post by The-Bus »

specialist wrote: post #253
kortex wrote: post #244

Earlier quoted context omitted.

https://www.weather.gov/ama/heatindex

Nice, thanks. FWIW, I just checked, and wunderground reports both temp and 'feels like', apparently matching the NWS Heat Index: https://www.wunderground.com/hourly/us/tx/dallas

The problem is that wet-bulb temperature is not the Heat Index or a "feels-like" temperature. Here's a bit more info: https://www.weather.gov/source/zhu/ZHU_Training_Page/definit...

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

#296

Post by Kungfuturtle »

rdevsrex wrote: post #267

Obviously no one wants this to happen, but I wonder about any possible mitigation strategies. Like creating homes and infrastructure under the ground, or at least covered by lots of insulation, like a Moon base covered with lots of dirt. Of course, that would completely suck for the people who have to live there, and we should do our best to prevent it, but some people probably aren't going to have a choice but to tr…

One kind of building that I came across is called an "Earthship", which relies on "thermal mass construction and natural cross-ventilation to regulate indoor temperature".[1]

It will be somewhat difficult to retrofit buildings to take advantage of e.g. thermal mass inertia, but I'm hopeful that new construction will increasingly favor passive/low-energy cooling methods.

[1] https://en.wikipedia.org/wiki/Earthship

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

#297

Post by gilbetron »

dalbasal wrote: post #190
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…

Well... people are resourceful. I mean, we may have gotten soft living in civilisation... but we still have some survival instinct. Shade, bathing, burrowing etc. Still, that factoid is troubling. These are conditions that exceed humans' operating conditions. We're used to that on the cold side. Plenty of people thrive (miserably) in places that get cold. But, there are actually far fewer good cooling options. Air co…

The human body can generate heat by eating food, it's just a matter of insulation to stay warm. Our bodies can't generate cool at a wet bulb of 35C. That's a huge difference.

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

#298

Post by mastax »

michaelbuckbee wrote: post #262
Stratoscope wrote: post #236

Earlier quoted context omitted.

> underground car parks tend to get hot too This is something that has puzzled me every time I park in the underground garage under City Hall in Palo Alto. It is always so hot down there compared to the outside air. I was about to ask if anyone knows why that is, and then realized I could search for the answer: https://www.google.com/search?q=why+do+underground+garages+g... Lots of interesting opinions there, includi…

This reminds me of how the London Underground used to be much cooler, but the trains have raised the temperature of the clay surrounding the tunnels sufficiently that it never cools off: https://en.wikipedia.org/wiki/London_Underground_cooling

Relevant: https://youtu.be/Y8RfeAmLfn8

There's also all the body heat, and the resistive braking of the trains which is being phased out.

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

#299

Post by spywaregorilla »

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…

I find it amusing that people are trying to downplay this because it is feasibly survivable in their opinions. If you're wondering "how I can survive these circumstances in my own home?" things are already really, really bad.

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

#300

Post by chinchilla2020 »

spywaregorilla wrote: post #299
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…

I find it amusing that people are trying to downplay this because it is feasibly survivable in their opinions. If you're wondering "how I can survive these circumstances in my own home?" things are already really, really bad.

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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