Wet Bulb temperature pushing the limits of human survivability

[Binkie The Clown]

Killing Heat — It Felt Like 165 Degrees in Iran Today

In Iran it was 115 degrees Fahrenheit today (46 C). Add in humidity and the heat index was a stunning 165 F (74 C). But what they really should be concerned about is the wet bulb reading…

A Limit to Human Heat Endurance

Thirty five degrees Celsius. According to recent research, it’s the wet bulb temperature at which the human body is rendered physically unable to cool itself in the shade. At which evaporation not longer cools the skin. A temperature that results in hyperthermia, heat exhaustion and heat stroke — even when sitting still and out of direct sunlight over the course of about 1-3 hours. Basically, it’s the physical limits of human heat endurance.

More at THE LINK (Robert Scribbler)

[cilla4progress]

1. And I just shockingly heard

on an NPR interview show that climate change will not be a big issue in the 2016 election!

Whistling past the graveyard...

Fiddling while Rome burns...


There are reasons for these cliches.

[Gregorian]

2. And more energy will keep going towards air conditioning.

Until we have carbon free energy generation, this will only add to our already increasing use of energy, resulting in yet more warming.

I pity the poor people living in these conditions. I have recently received emails from an ebay seller living in the South, and he's very unhappy with the continuously hot weather. I experienced more than I like, and it isn't a trend I invite for future generations.

[msongs]

3. 35C = 95 degrees F. we routinely worked outdoors all day in that kind of temp drank lots of water nt

[progree]

6. Wikipedia: "A sustained wet-bulb temperature exceeding 35 °C (95 °F) is likely to be fatal"

I haven't sorted out wet bulb and dry bulb yet, but this from Wikipedia
https://en.wikipedia.org/wiki/Wet-bulb_temperature

A sustained wet-bulb temperature exceeding 35 °C (95 °F) is likely to be fatal even to fit and healthy people, unclothed in the shade next to a fan; at this temperature our bodies switch from shedding heat to the environment, to gaining heat from it.[7] Thus 35 °C is the threshold beyond which the body is no longer able to adequately cool itself.

[Scootaloo]

16. "wet bulb" assumes 100% humidity

Which is to say, sweating has 0% chance to cool the body, since hte air is so wet that sweat doesn't evaporate.

[OKIsItJustMe]

21. This may help

Think of the old saw, "It's not the heat, it's the humidity."

My 9th grade Earth Science teacher taught us how to measure "wet-bulb temperature."

• Tie a thermometer to a strong piece of string
• Tie a bit of cloth around the "bulb" of the thermometer.
• "Wet" the cloth on the bulb of the thermometer.
• Whip the thermometer around in a circle over your head for a minute or more
• Stop, and quickly read the "wet bulb" temperature on the thermometer.

If the "relative humidity" is less than 100%, the "wind, blowing" on the cloth will cause water to evaporate, cooling the bulb of the thermometer, and making it read at a lower temperature than a "dry bulb." The lower the humidity, the more water will evaporate, meaning more cooling will take place, meaning the "wet bulb" temperature is lower.

If the "relative humidity" is 100% no water will evaporate from the cloth.

[progree]

22. Thanks OKIsItJustMe and Scootaloo. nm

[hatrack]

20. Yeah, and it probably wasn't 100% humidity . . .

But then, I wasn't there . . .

[GreatGazoo]

4. hey, they forgot to factor in the wind chill which takes it down to a refreshing 162F

[daleanime]

5. kick, kick, kick....

[moonbeam23]

7. And those fundies

make their women walk around covered in black heavy clothes from head to foot...fuckers

[Fred Sanders]

11. Gratuitous leap from weather to hate...thread winner!

The emoticon was not necessary.

[SoapBox]

8. 165????

Yikes...

I don't know what I would do...these poor people.

[procon]

9. A couple of years ago it was 112 here in California's Mojave Desert.

I had heat stroke many years ago and haven't been able to handle too much sun exposure or extreme heat stress ever since and I have to be very careful about going outdoors in hot weather. I was going to make a quick walk out to the mailbox, but when I opened the door the heat was like standing in front of a raging furnace. I could actually feel my skin tightening and it was uncomfortable to breathe in the dry heat. Even standing under the shade of the porch felt like I was getting a bad sunburn and that was as far as I got.

[tclambert]

10. When you cook meat to 160, it's well done.

[WinkyDink]

13. That's internal temperature, like 98.6. We'd be dead long before 160 internal.

[WinkyDink]

12. "THEY"??? Try "WE."

[GliderGuider]

14. Climate change has always been a migration trigger.

Bang.

[unblock]

15. if i understand correctly, 35c wet bulb temperature means evaporation only gets you down to 35c

for example, if the air is actually 35c and there's 100% relative humidity, so that there is no more evaporation, then eventually your whole body would be at 35c because your sweat can't cool it any lower than 35c.

drinking plenty of water wouldn't help lower your temperature (though it would help in other ways) because sweat doesn't work.

if the air is drier than 100% humidity, then it would have to be hotter to still have a wet bulb temperature of 35c, meaning sweat does work to cool your body, but still only from the hotter air temperature down to 35c, and no further.

[Elmer S. E. Dump]

25. 35C isn't a problem with body temperature being too hot - normal is 98.6

But with no cooling your body would quickly rise to over 105 which is deadly if not immediately treated.

[eppur_se_muova]

27. Normal is 98.6 F, same as 37 C -- so 35 C is a problem. nt

[Elmer S. E. Dump]

28. Not a problem of too much heat - too little heat - that was my only point.

[Erich Bloodaxe BSN]

17. Have I not been cynical enough?

Is Republican climate denial a deliberate attempt to kill off most of humanity, starting with those who live in hotter climates?

[WheelWalker]

18. Kicked and Recommended

[SheilaT]

19. Nearly 50 years ago, when living in Tucson, AZ

(It's a dry heat after all) we had a heat wave that lasted a week. Every single day it went over 110 degrees, and only one day did it not go over 115. I wound up with a mild heat something, stroke, exhaustion, not sure exactly what because I didn't go to the doctor. What I had was a killer headache that lasted three days. I had access to a/c, and I survived quite well. I have never liked hot weather, high, low, or medium humidity it doesn't matter to me. If it's too hot (anything above 75 degrees F) then I don't like it.

So even without global warming I'm astonished at the high temps many people live in.

But this? OMFG!

[jtuck004]

24. Oh great. Another wedge issue. n/t

[Elmer S. E. Dump]

29. I hope they make climate change a big issue in the general - they will lose BIG!

[gordianot]

26. It does give new meaning to a hot war zone.

Selling that carbon energy has consequences.