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Lots of people here not understanding wet bulb vs dry bulb. Wet bulb 95°F/35°C is considered the theoretical human survivability limit and is equivalent to a heat index of 160°F/71°C due to high humidity not allowing your sweat to evaporate.
In other words, it's very, very hot, bordering on unsurvivable.
While that is true, this map is referring to Wet Bulb Globe Temperature. The true wet bulb temperature is taken in the shade, while the WBGT is taken in full sun. These wet bulb temperatures aren't great, but they aren't yet approaching 95° which would be absolutely catastrophic.
Hey, you piqued my curiosity so I went and found the source ko-fi wet bulb temp article, and someone commented the same thing there! So maybe it was you or maybe you went to the source and learned and let everyone here know about it. Either way, thanks for the knowledge and correction to this!
Shitty news yes, but if that temperature means "you die", why isn't everyone without AC in that zone dead? Sensationalism does no one's cause any good.
According to wikipedia, prolonged exposure to wet-bulb temperatures above 35 °C means that you die. So 34.5 °C is still slightly below that limit, and presumably this was only the maximum during one day, i.e. it wasn't prolonged. The problem arises when you can't cool your body at any point during the day for a few days, which I naively imagine to be similar in effect to running a high fever that just doesn't go down. And there is a serious risk that the temperature rise due to the climate crisis could lead to such conditions (several consecutive days with wet-bulb temperatures above 35 °C) regularly, especially in the tropics, if global mean temperatures rise by more than 1.5°C (see e.g. here). Besides, I wouldn't be surprised if quite a few (in particular old) people did in fact die due to the heat.
like @Bbshot said, this picture is for wet bulb GLOBE temperature which isn't the same as the deadly wet bulb temperature in the article. Lazy/uninformed at best, misinformation at worst.
if you don't have AC, you need to get creative. you need to avoid being in that kind of heat and humidity, or lower the body temp through means other than evaporative cooling. if you can get underground, the temp will be lower, for instance. or you can get that underground coldness from your tap, and take a cold bath. strap ice packs to your body. whatever, but the situation is desparate.
anyways, there are ways to survive, but a wet bulb temp of 95F (equivalent to a heat index of about 160F) is considered the theoretical limit on human survivability, so it is unsurprising that people have died from this heat wave.
You do not die immediately. Not sure about those areas but here in the PNW, when the temperature creeps up we have started having cooling stations for people who are not able to stay cool where they live. There were still a couple hundred deaths during the last big heatwave.
Basically people are not stationary. If they are too hot, they will find cooler places. Problems arise with people who are not as mobile (elderly) or if there is a major power outage.
The wet bulb temperature is not stationary, BTW. It is dependent on relative humidity. The temperature for it is going to differ in places like Arizona where it is higher compared to more humid places like SE Texas where it is lower. It's basically the temperature where your sweat is not able to cool you down.
I've been without AC in Seville on a rowing competition with +40C, so basically no shade while doing heavy activity. It's true that we went to drink water and to the shade the moment we unloaded the boats, and that there was a recommendation to stay inside just in case, bu there were no reported deaths in 3-4 days.
This was an extreme, 42C ish, but I've been on 32 or 34 and while it's really uncomfortable (more because of humidity than heat but oh well), it's not mortally bad.
40C by itself isn't life threatening if the humidity isn't as high. The temperatures on their own regarding this heatwave were about 38C, but with the high humidity, the heat index exceeded 49C. I'm seeing a death toll of at least 14 so far.
bad info https://en.wikipedia.org/wiki/Wet-bulb_temperature vs. https://en.wikipedia.org/wiki/Wet-bulb_globe_temperature
Screenshot quality is pretty poor but the picture is globe. Text and temperature given in comment are not.
Could underground shelter be a viable option for surviving this type of weather?
There's a salt mine in Louisiana that's used for storing government documents, some old data tapes from the Apollo missions, etc. They use it for two reasons: dry air and constant cool temperatures. So, yes, if you go deep enough, you'll be surrounded by cool earth that will take much longer to heat up if you keep the air interchange down or funnel fresh air through enough cool earth before it gets to you.
Oooh boy, so you're saying we get the first opportunity to be the prime generation of mole people?
How do you prep?
Well, it stops being storing things in your basement, and turns into selling your house and migrating to a locale that is not experiencing wet bulb temps that'll kill you if you lose electricity. It's very hard to keep an A/C going if all you have is solar panels on your house.
And if A/C goes from being a luxury to being the ONLY reason you don't die--well, you either need to go somewhere where A/C can be a luxury again, or you pour massive amounts of cash into generating electricity on land you own...which is hard and expensive, which is why we typically rely on cities to set that stuff up for us as a public utility, because it's cheaper and more efficiant.
With climate change, the rust belt region around the great lakes is likely going to revitalize again, both because the availability of fresh water (avoiding what's going on around Denver and in California), and the cooler, northern temperatures. Also, old city infrastructure that can be finally updated if the cities start growing again and get a bigger tax base.
People who "prep" with a genuine long-range view of the future will do this sooner than later.
People who "prep" by stockping guns and whatever-the-fuck for a Mad Max type dystopia either get fucked where they live because they're not actually thinking about survival rationally and don't realize they actually DO need to sell their house and get somewhere safer, or they decide to migrate at the very last second and end up caught in the morass of other people who only migrate when the frying pan finally gets too hot to stand in.
That is a fantastic link, thank you. I've some friends moving en masse out of an area with water problems in the next year or so, and it's nice to be able to show them something like this.
The ones who survive it will breed and make kiddies that are more resistant to it. Problem solved!
EVOLOOSHUN!!
please tell me that was sarcasm
Most of humanity will die, but maybe some will live! /s
Twas :-)
This is probably not exactly what you're looking for, but I saw a video once of a simple geothermal "ac" system, where you basically bury a large vessel of water in the ground, and then use a system not dissimilar to a water bong to cool pumped air down and then pump the cooled air into your living area. The ground at around 6 feet into the ground is around 20 degrees cooler than the ambient air temperature on the surface. It's my understanding that this type of simple diy system would be most useful in third world countries, but it could be useful in case of grid failures too. I'll see if I can find the video
Here it is, like I said, I don't know how useful this would be in a survival situation, but probably better than nothing? Seems like this was meant to be built with materials that are easily found and available... This guy's channel also has a lot of helpful things for living off grid as far as power and stuff
Our future is fucked
Your future is up north or much further south.
thats likely true, but looking at this screenshot, a link to an article on ko-fi for fucks sake...
wet bulb isn't just temperature at all, its humidity and temp combined, to where your perspiration cannot cool you. saying wet bulb is 94F is silly when there are temps of 110 in places in the US and swaths of people arent dying in un-airconditioned apartments by the hundreds..
I am 100％ sure human caused climate change is real, and I'm 100％ certain we're in a lot worth trouble than we like to think, but this post is garbage
95° wet bulb is the heat index equivalent of ~160°, which exceeds the highest air temp ever recorded by ~30°. You can't really compare it to temps of 110°.
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sorry dude, I didn't realize what community I was commenting in, honestly.
In all honesty, you couldn't pay me to live in the south of the US. I just drove through rural NC a few weeks ago and holy fucking shit..
I hear you though, thanks for clarifying
Good thing we have AC
....you die......at 34.5 c.......without AC? I should go tell my ancestors that, they would have been long dead before they made me.
Wet bulb temperature. That's the part plenty of people are missing. This is the temperature/humidity combination at which the human body can no longer shed itself of heat.
I don't understand. I've been in 100+ degree weather often and been fine
It's about the combination humidity and temperature. For instance, I've been to Egypt in the desert where it's super hot, but also bone dry. Your sweat evaporates which causes cooling (evaporation costs energy). I've also been to Thailand in the hottest months, which is cooler than Egypt, but super moist. My sweat would not evaporate which made me feel so much more hot.
When the temp is above bodytemp and the humidity is high enough you will overheat.
Sweating cools you by taking heat away from you as moist vapor. When the air is already full of as much moisture as it can hold, sweating no longer works to cool you down — But your body keeps sweating in an attempt to cool down. You dehydrate, overheat, and die.