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

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251–260 of 414 posts

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

#251

Earlier quoted context omitted.

Having lived in Singapore for five years (2012-2017) (and worked out in the field for about 50% of that time) I can say that Singapore is one of the milder places to live. It never ever gets particularly hot (I genuinely can't recall a 100+ degree day in the entire time I was there), and the humidity, while, "sticky" is never really extreme. The thing that gets to you is that the climate never seems to change (with t…

> I can say that Singapore is one of the milder places to live. It never ever gets particularly hot Singapore is almost exactly on the equator. UV readings get up to 11 each day (extreme), whereas the most I ever saw in say SF was 5. Your experience is one experience, mine is that it's a sauna every day of the year. I've experienced extremely hot days in terms of subjective experience of WBT as explained in article.…

San Francisco is slated to just about hit 10 today.

Living in both San Diego and now Denver, they hit 11 quite regularly.

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

#252

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 have travelled to two countries where heat can hit that temperature, and they do not have the luxury of any AC, or in some cases even a fridge.

A few cities around the world do reach 35 or higher regularly during summer. And in a some of those people have lived for thousands of years.

https://en.wikipedia.org/wiki/List_of_cities_by_average_temp...

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

#253
post #244

Earlier quoted context omitted.

Ya, for messaging, "wet bulb" doesn't work well. We need a more intuitive phrase, like a "wind chill factor" for heat + humidity = danger. Edit: chewing on "wet heat factor". What do you think? Cliches like "but it's a 'dry heat' harhar" are already common. So "wet heat" might click.

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

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

#254

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…

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...

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

#255
post #115

Earlier quoted context omitted.

Swamp coolers do not work in high humidity. Running cool water from underground over oneself works, but is unsustainable and impractical. Going underground to someplace cool is also sometimes an option that does not require electricity, but is often impractical and highly situational. Ultimately all that really works in our modern world at scale in such a heat wave is powered air conditioning, so ensuring that electr…

You could potentially heat up a dessicant to dry it out and use that indoors to survive the humidity without having to go underground or have AC.

Interesting idea, though I'm not aware of any desiccants that would be appropriate for the scale we'd need to operate at here. Silica gel, for instance, wouldn't work because there's too much water to handle. Dehumidifiers could be used instead, but they heat up the air as they dry it out. I believe desiccants also heat up the air, but only slightly. Maybe they would heat up the air a significant amount if they were removing enough water from it for this scenario.

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

#256
post #6

Earlier quoted context omitted.

Little pedantic, but you meant "Wet-bulb" temperature ( https://en.wikipedia.org/wiki/Wet-bulb_temperature#Temperatu... ). I only know from owning a swamp cooler.

Isn't it basically the same as the dew point temperature? I believe a lot more people are familiar with that.

No, dew point is the temperature of an object on which air will start to condensate (because cooling the given air to the dew point lets relative humidity rise above 100 %, i.e. condensation). Wet-bulb temperature is the lowest temperature an object can reach through evaporative cooling (i.e. humans).

The two are the same only if relative humidity is 100 %: 100 % relative humidity means that if the air cools at all, it will condensate; so the air temperature is the dew point. 100 % relative humidity also means that water cannot evaporate, as the air is already saturated with water, so the wet bulb temperature is also the same as the air temperature.

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

#257

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 have travelled to two countries where heat can hit that temperature, and they do not have the luxury of any AC, or in some cases even a fridge. A few cities around the world do reach 35 or higher regularly during summer. And in a some of those people have lived for thousands of years. https://en.wikipedia.org/wiki/List_of_cities_by_average_temp...

Wet bulb temperature is not the same as average temperature. See https://en.m.wikipedia.org/wiki/Wet-bulb_temperature

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

#258

Earlier quoted context omitted.

Agreed. Europe struggled to relocate 2.5M of refugees over several years. What happens when people from India, the middle east, ... are forced to relocate? I expect some kind of conflict/war of expansion and probably famine since a lot of the land will be abandoned and hence become unproductive.

I'd expect the land to become unproductive first . A huge amount of agricultural land is threatened by the climate change, accelerated by other anthoropogenic effects such as soil erosion due to deforestation. Besides drought, heat, wind, and excess rainfall, there's flash floods caused by melting glaciers in the Alps, Himalayas, …

True. And at that point I really believe unrest will be widespread. The saying "We are 3 meals away from anarchy" will prove its veracity.

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

#259

Earlier quoted context omitted.

Karachi, and Sindh at large often goes through periods of +35 wet bulb. People can jump into fountains, or other bodies of water, hide at home, airconned buildings. In the end, people can try to brave it, and wait for the relatively cool evening.

Wet bulb thermometer is the kind that a pair of thermometers are mounted together with one wrapped in wet cotton and the other dry. Typically between the two glass tubes is a little look up table that gives humidity from current dry bulb temperature and delta between the two. I don't know what exactly environment reaching 35C/95F web bulb means, but considering 1) it indicates temperature of a thermometer cooled by e…

"I think it means evaporative cooling aka sweating is becoming useless. It won't be a huge stretch to consider that unsurvivable."

This assumes there are no alternatives to evaporative cooling via sweat.

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

#260
post #205

Earlier quoted context omitted.

"Many apartments don't have a bathtub, only a shower. And if everyone keeps tap water running, the pressure will drop down to trickle." People don't have trashcans, storage bins, etc? "And seems you probably never bathed in 35°C water, it's definitely not refreshing." Where is this 35C water coming from? Also, if it's a humid heat, there are likely to be natural or artificial bodies of water around. Hopefully the peo…

> 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.

Even if my air conditioner was still functional, its output, the attic-based tubing used to push the air around, and the cheaply-built and leaky house to which it all attaches would never be able to keep out the heat.
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