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

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121–130 of 414 posts

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

#121
post #51

Earlier quoted context omitted.

Lack of sun exposure can cause hypovitaminosis D, which is a known risk factor for COVID-19 and other infectious diseases. It also impacts nitric oxide production which is a factor in cardiovascular system health. Supplements can mitigate the problems to an extent but are inferior to natural sun exposure. And before anyone brings up skin cancer, there is no reliable evidence that brief daily sun exposure increases al…

> Supplements can mitigate the problems to an extent but are inferior to natural sun exposure. I've never heard of such a claim, and that seems unintuitive. Why would that be? Do you have a source you could direct me to to learn more about this?

Can't find it now, but this is probably based on a study/studies that I've seen that showed that lack of vitamin D is correlated with bad things, but supplementation doesn't fix the bad things nearly as much as you would expect. So, the idea some people have is that vitamin D is merely a correlate of something else that sun exposure does. I call it "sun magic" :)

...sometimes I secretly wonder if sunscreen (over-)use in America would one day be found to be the cause of rise in depression and other things like that over the last few decades, kinda like lead pipes of old. I don't think it's likely but it would be kinda funny.

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

#122
post #75

Earlier quoted context omitted.

When you use AC during nighttime you never get adapted to the heat. Try slowly phasing it out.

That's contradictory to leading sleep scientists like Matthew Walker, Peter Attia, etc. which is clear about need for chilly environment for sleep quality, eg < 21C. Granted, sleep science isn't oriented towards the genetics of the tropics yet, but there's plenty of evidence about temperature and sleep quality for more northern genetics anyway.

I agree with the parent. Killing the AC for weeks on end really helped me acclimate to the local temperature.

I'm not saying it resulted in quality sleep (as a Canadian - I set the thermostat to 13 degrees in the winter when sleeping, and my ideal temperature in the summer is about 18 degrees) - but you get used to the outdoor climate reasonably quickly (in my case, about 4-6 months).

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

#123

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…

> everyone living under such a heat wave will likely die.

I mean ground and buildings have thermal inertia, if the heatwave is relatively short you can survive in basements or underground parking. Also water in the pipes will still be colder than the air most likely.

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

#124

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…

If the water is still running - can't people spend a lot of time in the bathtub?

In the locations this happens, does everyone : have access to a bath (one per family member), running water (in a city were everyone is running a bath at the same time), a job where the aren't forced to go out and work every day to survive?

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

#125

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…

Genuine question: does old-style insulation not help? From when I was a kid I remember that a log house built using 60ies village technology (realistically probably more like 19th century technology), insulated with something stuffed in the triangles between logs and wallpaper and logs and planks (and partially eaten by mice ;)), stayed pleasantly cool on 90-degree days. And the dugout under it that we used to store potatoes and stuff like that was actually cold.

In a recent Seattle heatwave, when it was 107 outside my much poorer insulated semi-basement with direct sun shining into its large-ish windows, stayed under 85 without AC.

Couldn't people just build better / underground housing using relatively primitive technology?

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

#126

Similar question to this that I've been wondering this wildfire season -- at what point is AQI (Air Quality Index) too severe for human tolerance? The scale tops out at 500, what happens to a person if the air is even worse than that? Some sensors near Medford, OR are reading in the upper 400's and even low 500's -- what happens if it hits what would be the 1000's if the scale went that high? I'm mostly thinking of p…

I’m speaking out of my depth here but I believe exposure related disease is based on the particle density over time. Particles can clog the respiratory system, reducing blood oxygen and introducing free radicals. To a large extent the body is able to remove the debris, but if there is too much buildup due to prolonged exposure to high AQI then it can be difficult to recover without intervention.

I was at a chain drug store the other day and saw a display for canned oxygen, regular and Peppermint flavor!?! It seemed like another sign of the apocalypse to me, but maybe just a gimmick or stopgap for terrible air quality events.

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

#127
post #75

Earlier quoted context omitted.

When you use AC during nighttime you never get adapted to the heat. Try slowly phasing it out.

That's contradictory to leading sleep scientists like Matthew Walker, Peter Attia, etc. which is clear about need for chilly environment for sleep quality, eg < 21C. Granted, sleep science isn't oriented towards the genetics of the tropics yet, but there's plenty of evidence about temperature and sleep quality for more northern genetics anyway.

I don't think it is contradictory - that is the point of adaptation that you expose yourself to something that is not optimal and your body learns to handle it. Think of it as artificially changing the range of conditions needed for good sleep quality by training.

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

#128

Earlier quoted context omitted.

https://data.gov.sg/dataset/wet-bulb-temperature-hourly?view... The Changi airport weather station does not have any recordings of a 35C wet bulb temperature. And this paper suggests that it is a very uncommon occurrence as yet. What source are you using?

https://www.wbgt.sg/allstations

That is wet bulb globe temperature, not wet bulb temp. WBGT is calculated by adding together weighted WBT, globe temp and dry bulb temp.

See: https://www.instrumentchoice.com.au/news/wet-bulb-temperatur...

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

#129
post #34

Earlier quoted context omitted.

A lot of new technology could potentially solve this problem. There are certain types of roofs being installed called cool roofs that reflect heat and don’t absorb it that keeps the inside of building a little cooler.

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?

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

#130

[deleted]

It gets to 115+F where I live, sometimes for a few days. If you go outside bald in full sun without a hat, within seconds it feels as though your brain is cooking in your skull. It's liveable for a short stretch, but seriously discourages you from going outside. Parts of the garden crisp up and die in a day.
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