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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)

#271

Post by mordymoop »

cameronh90 wrote: post #191
poorjohnmacafee wrote: post #147

Earlier quoted context omitted.

> 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.…

" the most I ever saw in say SF was 5." Really? London is 6 today, was 7 last week and 8 earlier this year. I do also concur with the GP that Singapore is relatively mild as far as equatorial/tropical climates go. India, the Middle East, the Philippines and even Australia are sometimes much more oppressive. The hottest day ever recorded in Singapore was 37c, whereas London is 38c and SF is apparently 41c. Of course,…

It is unintuitive, but equatorial locations are usually stable and relatively moderate. They will tend to be uncomfortably warm year round, but never experience the temperature swings of locations much further north or south.

https://images.app.goo.gl/P4YtYRLvT5XVcn168

Look at this map of max temperatures and note that the equator runs through a band of relatively low max temperatures: Indonesia, northern South America, and the more southern part of Africa show bands of conspicuous coolness. The hottest max temperatures are in places like southern North America, India, Northern Africa, and Australia; locations that are in fact very far away from the equator.

The max temperatures of a place is caused by many things, such as proximity to water and local wind currents, but one driving reason is relatively simple: because of the tilt of the earth, every day on the equator is 12 hours. North or south of the equator, on the summer solstice, you can get 15 hour days, depending on latitude. The summer is a period of continuously intense solar heating. Again, there are other factors, but the sun is the driving force.

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

#272

Post by jefftk »

lmilcin wrote: post #177

I see a lot of uninformed people on this thread thinking 35C wet bulb temperature isn't such a big deal and proposing various ineffective tips to cool down. Let me explain what the issue is, in simple words: WET BULB TEMPERATURE IS NOT TEMPERATURE YOU SEE ON A THERMOMETER. (please, don't nitpick, I am aware of wet bulb thermometers) Wet bulb temperature is combination of temperature and humidity. The simple layman wa…

> going into cellar. The air will get cooler but the humidity will rise. You are going to die, unless you can cool the air DRY BULB temperature below 35C.

Don't you mean wet bulb temperature? Why would you need a dry bulb temperature below 35C?

> It will be shitty, wet, 100% humid, hot place, to sit half a day in with your family, kids and neighbors that don't have an expansive cellar like you, but at least you will survive

If we do start seeing this kind of temperature around the world, I expect people will start building underground refugees or repurposing existing structures.

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

#273

Post by rdevsrex »

xornox wrote: post #196
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…

How tens of millions people can escape underground or rivers? I think that there will not be space available for most of them.

I don't think space is the issue. Most people live 200 miles from the coast. If that gets as hot as the inland, people will fan out to find whatever shelter they can. While I hope there are cool materials science breakthroughs that can withstand high temperatures, I imagine a lot of people will make homes in caves and underground, like a nuclear bunker.

That would definitely change cultures and economies, but if you can't get out of those places, it might be your only option.

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

#274

Post by brmgb »

numpad0 wrote: post #202
baybal2 wrote: post #166

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 understand you are probably American and therefore not used to Celsius but just so you know the body of a human is around 37.7 °C. 40 °C is already life-threatening.

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

#275

Post by treebot »

mrfusion wrote: post #232
Dumblydorr wrote: post #221

Earlier quoted context omitted.

In your book, what counts as fixing climate while preserving human rights and dignity?

Good question. I could do some examples. Good: carbon tax or cap and trade (ideally revenue neutral). Electric car subsidies. Bad: climate lockdowns. Restricting travel. Travel credits. Social credit score tied to climate behavior. (This stuff keeps me up at night) So bottom line: Following this https://www.un.org/en/about-us/universal-declaration-of-huma... and this https://en.m.wikipedia.org/wiki/United_States_Bill…

What about just nationalizing the entire energy industry and everything related, instead of trying to work within the parameters of a free market for something with so many externalities?

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

#276

Post by robotguy »

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?

https://www.omnicalculator.com/physics/wet-bulb

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

#277

Post by lmilcin »

jefftk wrote: post #272
lmilcin wrote: post #177

I see a lot of uninformed people on this thread thinking 35C wet bulb temperature isn't such a big deal and proposing various ineffective tips to cool down. Let me explain what the issue is, in simple words: WET BULB TEMPERATURE IS NOT TEMPERATURE YOU SEE ON A THERMOMETER. (please, don't nitpick, I am aware of wet bulb thermometers) Wet bulb temperature is combination of temperature and humidity. The simple layman wa…

> going into cellar. The air will get cooler but the humidity will rise. You are going to die, unless you can cool the air DRY BULB temperature below 35C. Don't you mean wet bulb temperature? Why would you need a dry bulb temperature below 35C? > It will be shitty, wet, 100% humid, hot place, to sit half a day in with your family, kids and neighbors that don't have an expansive cellar like you, but at least you will…

I mean DRY BULB temperature. Reducing dry bulb temperature == removing heat. Reducing wet bulb temperature == removing humidity.

But it doesn't matter a lot, because at 100% humidity (required to spontaneously dew humidity out of air) dry bulb temperature equals wet bulb temperature.

Dry bulb changes indpendently of wet bulb temperature but cannot be lower than wet bulb temperature.

Because when air temperature (dry bulb) reaches wet bulb temperature you are at dew point and when you cool down further all that moisture is going to either cause mist or dew or snow or rime.

In fact, lowering DRY BULB temperature under dew point (WET BULB temperature) is the leading way to remove humidity in nature -- the water precipitates in the form of mist high up in the atmosphere, the mist coalesces into droplets and falls down on air as rain. Alternatively, if the temperature is below zero, it causes snow by sublimation (both wet and dry bulb temperatures are equal.

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

#278

Post by [deleted] »

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?

[deleted]

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

#279

Post by beervirus »

tomrod wrote: post #206

I wonder if people confuse wet bulb and dry bulb here. Wet bulb is related to how well your air conditioner or sweating will cool you. Dry bulb is what we usually say when taking a temperature reading, or listening to the local news' meteorologist.

Wet bulb temperature doesn’t have anything to do with air conditioning, unless you’re only talking about evaporative coolers.

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

#280

Post by Maursault »

Stratoscope wrote: post #236
rini17 wrote: post #165

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. 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…

> 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…

Hello 2013: https://news.ycombinator.com/item?id=5997368
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