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

advances.sciencemag.org

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

#241

Post by throwaway894345 »

fighterpilot wrote: post #185
shadilay wrote: post #99

Earlier quoted context omitted.

While it's great and all for america to invest in the environment at the end of the day america is still only a small part of the world. The issues of climate are global in nature and unlikely to be solved in my lifetime.

The US needs to be leading on this issue. They're the largest economy and have benefited the most out of everyone (on a per-capita basis) from the carbon pollution that they're causing, leaving the poorer and hotter countries in the global south to bear the brunt of the downside a century later.

Agreed. It’s going to be pretty lame when Biden tries to convince the world to do better on climate at the upcoming summit when Biden can’t get significant policy implemented at home. Anyway, every country needs to do its part and ours, like many others, is failing.

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

#242

Post by IgorPartola »

selimthegrim wrote: post #239
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...…

I’m pretty sure Jacobabad has cars.

Some people having cars != everyone having cars.

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

#243

Post by scythe »

twic wrote: post #160
sudhirj wrote: post #88

There are two cities in India that are pretty close by where this difference is very clear. Chennai is on the coast, while Bangalore is inland at a higher altitude while they’re both pretty much the same latitude. The difference in perception even if the dry bulb temperature is the same is insane. In Bangalore I can always find shade and it’ll be cool instantly, but in Chennai my whole body is always soaking wet, my…

It's striking to me that according to the map in figure 4, the parts of the Indian subcontinent most at risk are in the Indus and Ganges valleys. Areas hundreds of miles further south (including Chennai and Bangalore) are safe! Why is this? I see that the south is much more mountainous [1], whereas the Indus and Ganges valleys are very flat (hence that term "Indo-Gangetic Plain"). Is it just the combination of being…

The seabreeze colliding with the mountains in South India likely results in significant cloud cover, which cools the surface by reflecting sunlight. You can see here that the southern region has less total sunlight per year (lighter = cloudier):

https://en.wikipedia.org/wiki/Sunshine_duration#/media/File:...

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

#244

Post by kortex »

specialist wrote: post #229
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.

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

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

#245

Post by giantg2 »

Aeolun wrote: post #205
giantg2 wrote: post #201

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.

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 temperature. That could be 35C with 100% humidity, or it could be a higher temperature with a lower humidity.

Can you explain how your air conditioner keeps you cool? Do you think this machine is the only thing that can perform a similar function? It's all about removing excess heat from your body. An air conditioner does this by cooling air and removing humidity. This can be from the cool air on your skin and the ability for your sweat to evaporate. When your sweat can't evaporate you need another way to transfer heat. Water is very efficient for this due to its specific heat (anything at a cooler temperature with sufficient thermal mass can work). Some people can even become hypothermic in 27C water if left in it long enough.

Edit: I guess people just downvote things they don't like or find to be inconvenient.

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

#246

Post by IgorPartola »

Dumblydorr wrote: post #224

Can we start considering high tech solutions to actively cool the planet? We're going to slowly work on carbon, but it won't be fast enough. In the meantime, We need to prevent heat getting to Earth, either via more cloud cover or space mirrors in the LaGrange point. I'm not a fan of either, but what's the alternative? Bake to death while the powerful decision makers delay changing anything?

We can’t. Let’s say that you find a magic box that can offset 20% of the carbon emissions globally. Yay you just reduced carbon emissions. But there is no budget for carbon emissions. So those who produce it (agriculture, heavy industry) can now feel free to just produce more CO2 and toss it into the air. Besides, not every place is as industrialized as the US or China but they want to be. So the emissions will soon catch up to the old levels while your machine is cranking at full speed.

It’s the equivalent of getting a second job because you can’t stop spending money: it’ll offset when you go broke but won’t prevent it. The only way to fix this is to tax the shit out of anything that pollutes with CO2 or other greenhouse gasses (which will naturally be passed on as a cost to consumers). There is jo other way out.

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

#247

Post by dirtyoldmick »

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…

Web bulb? I think you mean wet bulb. Unless we've gotten spiderman involved.

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

#248

Post by jameshart »

twic wrote: post #160
sudhirj wrote: post #88

There are two cities in India that are pretty close by where this difference is very clear. Chennai is on the coast, while Bangalore is inland at a higher altitude while they’re both pretty much the same latitude. The difference in perception even if the dry bulb temperature is the same is insane. In Bangalore I can always find shade and it’ll be cool instantly, but in Chennai my whole body is always soaking wet, my…

It's striking to me that according to the map in figure 4, the parts of the Indian subcontinent most at risk are in the Indus and Ganges valleys. Areas hundreds of miles further south (including Chennai and Bangalore) are safe! Why is this? I see that the south is much more mountainous [1], whereas the Indus and Ganges valleys are very flat (hence that term "Indo-Gangetic Plain"). Is it just the combination of being…

The article indicates that in tropical regions cloud cover has an impact on maximum temperature reached; subtropical regions have less consistent cloud and so have stronger heatwaves.

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

#249

Post by bostonsre »

trhway wrote: post #22
bostonsre wrote: post #9

Earlier quoted context omitted.

Or.. Build more basements and underground shelters.

No, it wouldnt work as the heat would have nowhere to go. And the mid east people didn't do it - https://en.m.wikipedia.org/wiki/Windcatcher Instead you build and live in highrise/towers - that gives cheap ventilation which is a half the solution. And I liked the siesta and the following it very active life till deep night in Spain - another natural adaptation to hot climate. It makes for much calmer and steady life…

You can build ventilation or even just building houses with basements would help a bunch. The temperature underground is a lot more cool and steady and would help you escape the heat. There is a town in Australia that does exactly this because it's so friggin hot:

https://en.m.wikipedia.org/wiki/Coober_Pedy

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

#250

Post by kvgr »

poorjohnmacafee wrote: post #52
princeb wrote: post #42

Earlier quoted context omitted.

i probably have a comment somewhere recently, but singapore is already in WBT >35 conditions in the day. it eases to around 30 at night or when rain falls. as long as power is running, it's actually fine in this country, but that's because we've designed our living space around the heat. it is entirely possible to never be exposed to the sun in a normal day in the life of a working resident here if you stay in the ri…

Yes, I sometimes feel like I'm at death's door when jogging outdoors. Myself and some Westerners I know haven't "adapted", even after years being here. The strategy is just always have ice water in hand if outdoors for prolonged time. I sometimes get laughed at for not adjusting to the heat, but I think it's just too much for some genetic lineages from outside tropics. Unfortunately a large percentage of folks in HDB…

Big factor is body fat, when I was very skinny I could take higher temperatures than 40pounds later. It made basically 5 celsius degrees difference of "quite nice and warm" vs "too hot to operate" temperature.
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