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View Full Version : What's The Coldest Temperature Tolerable for Humans?



Mr. Milton Banana
2004-Apr-28, 08:24 PM
At Vostok, Antarctica, at this moment, it is -97 degrees Fahrenheit. What is the lowest temperature tolerable before humans have to change into a space suit?

Has anyone here experienced this kind of cold-and what is it like?

:-k

Mr. Milton Banana
2004-Apr-28, 08:27 PM
Oops-I forgot; here's where I got this forecast:

http://www.wunderground.com/global/stations/89606.html

8)

ToSeek
2004-Apr-28, 08:40 PM
Well, the bottom line is that any exposure to temperatures below freezing will lead to frostbite sooner or later. Actual exposure to a temperature of -97 would lead to frostbite in a matter of seconds. Other than that, I think it's a matter of what you define as a "spacesuit." Certainly at those temperatures you need to be very well bundled up, though perhaps not sealed in.

Frostbite/wind chill chart (http://www.in.gov/isdh/bioterrorism/manual/windchillchart.htm)

Mr. Milton Banana
2004-Apr-28, 09:05 PM
Well, the bottom line is that any exposure to temperatures below freezing will lead to frostbite sooner or later. Actual exposure to a temperature of -97 would lead to frostbite in a matter of seconds. Other than that, I think it's a matter of what you define as a "spacesuit." Certainly at those temperatures you need to be very well bundled up, though perhaps not sealed in.

Frostbite/wind chill chart (http://www.in.gov/isdh/bioterrorism/manual/windchillchart.htm)

Forgive my ignorance on what would qualify as a spacesuit. :oops: In my mind, I'm thinking about the type you'd wear on the moon or in space-something sealed, as you said.

Given what you've said, perhaps I should refine my first question to: at what low temperature point would it become necessary to wear a sealed suit?

I hope this helps. 8-[ I'm here to learn. :D

tjm220
2004-Apr-28, 09:31 PM
Is the -97F the actual temp or wind enhanced? Coldest I've experienced was in Saskatchewan with an actual air temp of around -40C with the windchill making it seem like -70C. Bundled up a lot to the point where it seemed like a spacesuit :D

Mr. Milton Banana
2004-Apr-28, 09:38 PM
Is the -97F the actual temp or wind enhanced? Coldest I've experienced was in Saskatchewan with an actual air temp of around -40C with the windchill making it seem like -70C. Bundled up a lot to the point where it seemed like a spacesuit :D

The wind is WSW @ 2 mph. The actual temperature is -97. Just click on the link I provided. :)

Is it a numbing, painful cold that you felt?

tjm220
2004-Apr-28, 09:43 PM
Is the -97F the actual temp or wind enhanced? Coldest I've experienced was in Saskatchewan with an actual air temp of around -40C with the windchill making it seem like -70C. Bundled up a lot to the point where it seemed like a spacesuit :D

The wind is WSW @ 2 mph. The actual temperature is -97. Just click on the link I provided. :)

Is it a numbing, painful cold that you felt?

The few tiny fractions of exposed skin felt intense pain. Heavy winds pushed me around and the slapping of clothing layers was unpleasant as well.

Mr. Milton Banana
2004-Apr-28, 09:53 PM
Another place where you can check the latest weather at Vostok:

http://www.antarcticconnection.com/antarctic/stations/vostok.shtml

It's almost 4 a.m. there now.

Brady Yoon
2004-Apr-28, 11:57 PM
The coldest temperature I've experienced, sadly enough, was 29 degrees F, in the middle of a desert town outside Death Valley NP. Kinda ironic. With sweatpants and a light jacket on, it wasn't cold at all. :o :)

Brady Yoon
2004-Apr-28, 11:59 PM
On the other side of things, is it possible for a person to survive 136 F heat, discounting the effect of humidity. (assume you are supplied with water and necessary supplies.

Avatar28
2004-Apr-29, 12:02 AM
On the other side of things, is it possible for a person to survive 136 F heat, discounting the effect of humidity. (assume you are supplied with water and necessary supplies.

I believe I read somewhere that with no humidity, a human can survive temps pushing 200 for quite some time, as long as they make sure to stay adequately hydrated. Sweating is a quite effective means of cooling apparently.

bearcub
2004-Apr-29, 12:10 AM
My personal best was during the 18 months I spent in Fairbanks, AK compliments of the USAF. We had a week where it stayed at -60 F. I definitely needed more than sweatpants :o . Full parka, mukluks, thermals, etc.
I guess the AF folks saw a chart similar to the one ToSeek referenced. We had to work outside, but were limited to no more than 30 minutes.
Luckily, no wind. Just reeeeeeeeeeeeally cold.

Charlie in Dayton
2004-Apr-29, 04:12 AM
I vaguely remember reference in Guinness to experiments where naked humans endured 400F, and heavily clothed ones 500F...that one needs checkin' out, 'cause that seems just a tad warm to me...

Normandy6644
2004-Apr-29, 04:19 AM
Down here in Florida the coldest tolerable temperature is around 72F. 8)

tuffel999
2004-Apr-29, 04:23 AM
Personally the coldest I ever hit was -20 sitting on a lake ice fishing.........so very cold when you are sitting on ice, its windy, and -20.

The hottest was 118(at least that is wha tthe thermometer said on my backpack). 2% humidity so it wasn't so bad. Now 103 and 98% humidity in the summer at home darn near killed me.

scottmsg
2004-Apr-29, 04:40 AM
I vaguely remember reference in Guinness to experiments where naked humans endured 400F, and heavily clothed ones 500F...that one needs checkin' out, 'cause that seems just a tad warm to me...

I also remember something like that. I think I read about it in a yearbook from Encyclopedia Britannica that my dad used to receive. Unfortunately, it is in a box in my attic right now, so I should be able to find it in a couple of years. :D

The coldest temperature I've ever experienced is -11 going to school one morning in Nebraska. The warmest was in Biloxi, Mississippi, where it was 93 degrees with very high humidity every day in the summer.

cyswxman
2004-Apr-29, 05:26 AM
I'm not sure what the lowest temperature for human survival would be, but I know it hinges a lot on heat transport. -97 is tolorable if there is no wind, as exposed skin would essentially lose heat by radiation into the air, which is not very efficient. Add a 10 mph breeze and one loses heat a lot quicker. Interestingly, I have read of something at the south pole station called the 300 Club. They wait until the air temperature is -100F, then turn the sauna up to 200F. Those wishing to join go into the sauna for as long as they can, then run (although a fast walk is advised) outside to the actual south pole marker, thus subjecting thier bodies to a 300 degree change. I'd like to try that sometime.

Madcat
2004-Apr-29, 06:23 AM
That's a decent way to get Pneumonia. Not the cold mind you, the temperature differential. When I was a kid, I had the PC in the only air conditioned room in the house. I'd run out on errands... and by the end of the summer I had a nice infection.

kucharek
2004-Apr-29, 06:58 AM
I guess that depends on the clothing you use and other stuff. If you are perfectly isolated, you only use body heat with your breath. Now you can think of some heat exchange mechanismn - more sophisticated than your nose - that takes the warmth out of the air you breath out and uses it to warm the air you breath in. If you can make this heat exchanger so efficient, that you don't lose more heat than your body produces, you should be able to stand any low temperature you want.

Harald

tuffel999
2004-Apr-29, 02:01 PM
That's a decent way to get Pneumonia.

Exactly how? Pneumonia is most often caused by a bacteria (http://www.cdc.gov/ncidod/diseases/submenus/sub_pneumonia.htm)and the bacteria has to present for you to get it. As far as I can remember none of the causitive bacteria are cold resistant. You do not get pneumonia or a cold from the cold. They are caused by microorganisms.

SiriMurthy
2004-Apr-29, 02:09 PM
The wind is WSW @ 2 mph. The actual temperature is -97. Just click on the link I provided. :)


WSW? Doesn't everything point to North once you are at the South Pole? Vice versa similarly. :o #-o

SiriMurthy
2004-Apr-29, 02:16 PM
That's a decent way to get Pneumonia. Not the cold mind you, the temperature differential. When I was a kid, I had the PC in the only air conditioned room in the house. I'd run out on errands... and by the end of the summer I had a nice infection.

I thought pneumonia is bacterial. at -97deg F, I believe that such bacteria can't survive.

SiriMurthy
2004-Apr-29, 02:17 PM
That's a decent way to get Pneumonia. Not the cold mind you, the temperature differential. When I was a kid, I had the PC in the only air conditioned room in the house. I'd run out on errands... and by the end of the summer I had a nice infection.

I thought pneumonia is bacterial. at -97deg F, I believe that such bacteria can't survive.

tuffel999 beat me to it. :)

Mr. Milton Banana
2004-Apr-29, 03:14 PM
The wind is WSW @ 2 mph. The actual temperature is -97. Just click on the link I provided. :)


WSW? Doesn't everything point to North once you are at the South Pole? Vice versa similarly. :o #-o

LOL! True enough. :D

Don't shoot me-I'm just the messenger. :P :)

SiriMurthy
2004-Apr-29, 04:22 PM
Don't shoot me-I'm just the messenger. :P :)

I won't. :)

I wonder though, what does a magnetic compass show at the poles.

Philippe
2004-Apr-29, 04:39 PM
As a kid (1979 or 1980), I remember one morning around -55C (close to -70F), and that was before windchill. That was in the Laurentides, 2 hours north of Montreal. The snowsuit I was wearing was a one piece affaire with a hood. Sometime, I feel like the only difference between our winter clothes up here and a spacesuit, is that they aren't airtight!
:P

Philippe

iFire
2004-Apr-29, 05:32 PM
Well, if you were at a TRUEPOLE :P then it would still point to magnetic north, I wonder what it would do at the magnetic poles. :o

Avatar28
2004-Apr-29, 05:41 PM
Don't shoot me-I'm just the messenger. :P :)

I won't. :)

I wonder though, what does a magnetic compass show at the poles.

It would orient towards the magnetic pole. I believe the physical poles are far enough away for that to happen. If you're to close to the magnetic poles, though, it'll just drift somewhat randomly I believe.

Dgennero
2004-Apr-29, 05:57 PM
The lowest tolerable temperature, at least for some time, would IMO be zero Kelvin - provided that there is no air around you.
The air molecules slow down your temperature, water does the job even faster.
With only a space helmet and air to breathe, the body should be able to stand exposure to outer space for some time.
Any volunteers? :o

Parrothead
2004-Apr-29, 08:24 PM
I don't think I'd like to experience the cold of the Antartic. Around here in winter the temp. might get down to -35 C with a windchill pushing close to -50C. February of !990 or may have been 91, we had a three week stretch where the temp didn't get above -30 C. Hottest I've been exposed to, not counting sauna at a nice 80 - 85 C (nice dry heat). On travels in Australia late '88 early '89, Melbourne and Sydney were nice avg temp in the mid to high 20's, the temp in Cairns was a balmy 38 C plus 90 % humidity ... ick! but beautiful :D One day, I'd like to see more of Australia.

JohnOwens
2004-Apr-29, 09:45 PM
The wind is WSW @ 2 mph. The actual temperature is -97. Just click on the link I provided. :) WSW? Doesn't everything point to North once you are at the South Pole? Vice versa similarly. :o #-o
And for that matter, is the wind then from the North, or to the North?




Don't shoot me-I'm just the messenger. :P :) I won't. :)

I wonder though, what does a magnetic compass show at the poles. It would orient towards the magnetic pole. I believe the physical poles are far enough away for that to happen. If you're to close to the magnetic poles, though, it'll just drift somewhat randomly I believe.
I think that, given enough freedom to swing in three dimensions instead of just two, it will point almost vertically, since that's the direction of the magnetic field at the surface there, much like the iron filings on a bar magnet will point away from its poles at the ends.
If it's limited to the horizontal, then it'd probably just swing somewhat randomly like you said.

SiriMurthy
2004-Apr-30, 03:35 PM
I think that, given enough freedom to swing in three dimensions instead of just two, it will point almost vertically, since that's the direction of the magnetic field at the surface there, much like the iron filings on a bar magnet will point away from its poles at the ends.
If it's limited to the horizontal, then it'd probably just swing somewhat randomly like you said.

Yes, I believe it makes sense to say that. Sorry, I should have clarified in the first place that when I mentioned "Poles", I actually meant the magnetic pole. I often forget the fact that the physical poles and the magnetic poles are at different places.

Thanks for the replies.

Majestic_Eagle
2004-May-01, 04:51 PM
Living in Winnipeg, the coldest city (pop. >500,000) in North America and one of the coldest cities (pop. >500,000) in the world, the coldest I have experienced is -49C (without windchill). With windchill, I think it was -60C to -65C. I don't quite remember as this was a long time ago, and almost every january the mercury dips around or below -40C for at least a few days or nights. This January the warmest it got for an entire week was -35C. It's pretty crazy, when you open a door outside (if it's a metallic door knob), your hande immediately gets stuck to the handle. Of course, you can still take it off, but it can hurt a lil'.

Anyways, the hottest I've experience was probably around 100F (excluding humidity) in St. Louis, Missouri. I was there with my family in July of 1997 or 1998 and the humidity was just crazy. We had to shower 2-3 times a day and we drank water non-stop. It didn't help that we were staying at a campground with very lil' trees and shade in a trailer with no a/c. Nevertheless, I had a blast. I loved St.-Louis and would go there again in a heart beat.

Btw, check out how well we treat royalty in Winnipeg:
http://www.guardian.co.uk/jubilee/story/0,11550,807389,00.html

And that was in October, old man winter hadn't even arrived yet.

Wingnut Ninja
2004-May-01, 07:29 PM
Interestingly, I have read of something at the south pole station called the 300 Club. They wait until the air temperature is -100F, then turn the sauna up to 200F. Those wishing to join go into the sauna for as long as they can, then run (although a fast walk is advised) outside to the actual south pole marker, thus subjecting thier bodies to a 300 degree change. I'd like to try that sometime.

I was about to take issue with this when I realized you were talking about a sauna (air) rather than a hot tub (water). A 200 degree hot tub sounds a little painful.

Joel Clifton
2004-Nov-12, 11:58 PM
On the other side of things, is it possible for a person to survive 136 F heat, discounting the effect of humidity. (assume you are supplied with water and necessary supplies.

I was in a sauna that was at about 195 degrees Farenheit, and I was in there for several minutes.

Tunga
2004-Nov-13, 02:05 AM
My brother lives in Fairbanks, Alaska. It can get down to -50 F and stay there for awhile. In one of these cold spells, he decided to go into town on a snowmobile. This put him at a wind chill of -100 F. Even though the was dressed with several layers, the half hour ride was mighty cold. He decided he would never repeat this again.

dvb
2004-Nov-13, 11:02 AM
I once replaced the starter in a ford pinto that I used to own living in Winnipeg. The temperature was -30C at the time, and I had to get the car out of the lot before I got it towed on me. Luckily I have a nice big parka that kept me warm while working underneath the car with the engine jacked up off of the mounting plate. :-?

I've experienced much colder mind you, and I always dress prepared. Ever since I got frostbite on my ears one winter as a child, I've worn my toque (https://suki.freestylenetworks.com/csa/catalog/images/CSA%20Toque%202.jpg) every winter since.

toolazytotypemyname
2004-Nov-13, 03:17 PM
the coldest outdoor temperature I've experienced was -36F with very little wind. I found it difficult to breathe the air without tucking my face into my jacket. The other problem is that the stuff in your nose starts to freeze up.

When I worked at the Army Cold Regions Lab in Hanover, one day I had to move some snow from the storage freezer to a lab in a different building. The storage freezer was kept @ -60F, outside it was about 90F with high humidity (it was August) and the lab was kept right around 0F. So I guess that puts me in the 150 club, right?

Evan
2004-Nov-13, 03:20 PM
A magnetic compass doesn't work near the magnetic poles. It is subject to an effect called "compass dip". This effect becomes important quite a distance from the poles and makes a magnetic compass useless. The area in which this occurs is called the "area of compass unreliability". It happens of course as the angle of the field lines grows more vertical than horizontal. For that reason pilots (I am one) must learn celestial navigation if they are to fly in this area.

150 club? We have that here without artificial means. The warmest ever here was around 101F and the coldest -49F. Just to the west of here is a weather station at Puntzi Mtn. It has gone below -60F. I didn't mention that the day I was out (Edmonton) in -55 it was a blizzard with the wind at 60mph.

Squink
2004-Nov-13, 03:27 PM
You can safely dip your arm in in dewer of liquid nitrogen (-196C). The Leidenfrost effect, and the heat capacity of the water in your arm prevent injury for 30 seconds or so. Air and vacuum are very poor conductors of heat, so it'll take a while to freeze under even the most extreme conditions.

Evan
2004-Nov-13, 03:42 PM
I've also been told that you can stick your finger into molten lead for a moment. I'm not going to try either one :eek:

Joel Clifton
2004-Nov-13, 04:41 PM
You can safely dip your arm in in dewer of liquid nitrogen (-196C). The Leidenfrost effect, and the heat capacity of the water in your arm prevent injury for 30 seconds or so. Air and vacuum are very poor conductors of heat, so it'll take a while to freeze under even the most extreme conditions.

I can't believe that. Even in weather of 0 degrees Farenheit, a good gust of wind will burn my skin, and make it numb for a while. Air at -127F would easily be able to kill my skin that fast. liquid, which is a much better transferer of heat than air, at -320F, should freeze the surface of your skin in a fraction of a second.

Think of this. Have you ever put your hand into freezing water? It burns terribly, and your skin goes numb in a half a minute. And that water is about 30-35F.

Evan
2004-Nov-13, 05:53 PM
I've used LN2 quite a bit over the years starting when I worked at the Rad Lab. It calls for a face shield and welders gloves as it will burn you just as fast as molten metal.

Squink
2004-Nov-13, 06:10 PM
I can't believe that.
Think of this. Have you ever put your hand into freezing water? It burns terribly, and your skin goes numb in a half a minute. And that water is about 30-35F. Dipping your hand in liquid nitrogen is a common chemistry/physics lecture demonstration. Here's a bit on LN safety (http://www.physics.uq.edu.au/people/gilmore/demos/ln2safety.html). I've stuck my own hand in a nitrogen dewer, and it's still attached, and fully functional.
Boiling nitrogen, air, and vacuum are all lousy heat conductors, so it takes a while for them to cool the skin. Water, as you mention, is quite a good conductor, and it will suck the heat out of your hand quickly.

Bozola
2004-Nov-13, 10:53 PM
I can't believe that.
Think of this. Have you ever put your hand into freezing water? It burns terribly, and your skin goes numb in a half a minute. And that water is about 30-35F. Dipping your hand in liquid nitrogen is a common chemistry/physics lecture demonstration. Here's a bit on LN safety (http://www.physics.uq.edu.au/people/gilmore/demos/ln2safety.html). I've stuck my own hand in a nitrogen dewer, and it's still attached, and fully functional.
Boiling nitrogen, air, and vacuum are all lousy heat conductors, so it takes a while for them to cool the skin. Water, as you mention, is quite a good conductor, and it will suck the heat out of your hand quickly.

Yup. I used to play with LN2 all the time as well; it has a lousy heat capacity, unlike water. You can still burn yourself if you're not careful, especially if you get any caught in your clothing. The problem I keep seeing is that people do not understand the difference between heat and temperature.

Evan
2004-Nov-13, 11:07 PM
Bozola,

I think most people understand it when reminded. A bathtub of lukewarm water has far more heat than a burning match but a match has a far higher temperature.

Joel Clifton
2004-Nov-14, 01:17 AM
I know the difference between heat and temperature, but I figured that if water could draw heat away quickly, liquid nitrogen could.

I was also thinking of my experiences with spraying butane on my hand, which will quickly freeze my epidermis through evaporation. Since liquid nitrogen has a much lower boiling point, I figured that it would do it much faster.

Bozola
2004-Nov-14, 01:51 AM
I know the difference between heat and temperature, but I figured that if water could draw heat away quickly, liquid nitrogen could.

I was also thinking of my experiences with spraying butane on my hand, which will quickly freeze my epidermis through evaporation. Since liquid nitrogen has a much lower boiling point, I figured that it would do it much faster.

Heat of vaporization of nitrogen is 2.79 kJ/mol, water is around 40.5 kJ/mol.

Mr. Milton Banana
2004-Nov-14, 05:47 PM
I've also been told that you can stick your finger into molten lead for a moment. I'm not going to try either one :eek:

LMAO!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

:lol: :lol: :lol: :lol: :lol: :lol:

=D> =D> =D>

Ow, ow, ow-the PAIN!!! Good comeback!! :D

If I were drinking my coffee, I'd spew it all over the monitor. You're lucky, dude. You would have to get me another one if that happened. [-X

It's cool ( ;) ) to see this thread bumped up again.



:)

The Supreme Canuck
2004-Nov-14, 06:26 PM
I've also been told that you can stick your finger into molten lead for a moment. I'm not going to try either one :eek:

I've seen it. You have to have a wet hand, and you can only do it for half a second. The water flashes to steam and keeps the lead from coming into contact with your hand. Actually quite cool to watch.

scottmsg
2004-Nov-14, 08:45 PM
I've also been told that you can stick your finger into molten lead for a moment. I'm not going to try either one :eek:

I've seen it. You have to have a wet hand, and you can only do it for half a second. The water flashes to steam and keeps the lead from coming into contact with your hand. Actually quite cool to watch.

I think I'll take a pass on trying that. Would be fun to see though. :o

The Supreme Canuck
2004-Nov-14, 08:55 PM
Hey, you'll never catch me doing it, either.

Byrd
2004-Nov-14, 10:43 PM
The lowest temperature humans can survive depends on a lot of things. The Inuit and Inupiat (Eskimos), for instance, are adapted to living in colder weather and can stroll around without gloves (or as we saw in a film, getting wet in icy waters) and suffer no ill effects. Me, I'd be a dead and frozen bird-sicle inside two minutes.

However, I'm a Texan. I've gone jogging in 110 degree temperatures in Lubbock with no ill effects.

So... you'd have to clarify that question: nude human? clothed human? Which genetic group? Which global region do they live in? What other conditions occur?

frogesque
2004-Nov-14, 11:21 PM
Mad dogs and Englishmen (http://www.sabrizain.demon.co.uk/malaya/coward.htm)

Evan
2004-Nov-15, 02:48 AM
Sorry, I am having a moment here... Heee... heeee...

I have been known to sit on the back deck of my house in my birthday suit. When the religious un-invited come calling they get quite a suprise. Especially so since my house is extremely private and not even viewable from the road. It is their problem, not mine. Private property.

amstrad
2004-Nov-15, 09:36 PM
I wonder though, what does a magnetic compass show at the poles.

A manetic compass tries to align itself with the magnetic field lines. At the magnetic poles, those are perpendicular to the ground, so the compass will try to dip into the ground.

So the answer is: it depends on the how your compass handles dip. A standard field compass (rotating disk on a point) will behave erratically, while a sphere in a fluid filled sphere will point to the ground.

Evan
2004-Nov-15, 10:01 PM
There are compasses made specifically to measure dip. They are not suprisingly called a dip compass.

Example (http://eost.u-strasbg.fr/musee/En/magn/boussole_incl.html)

toolazytotypemyname
2004-Nov-16, 01:30 AM
I think it definitely depends on where you are from. I had a coworker from Ghana who would wear a winter coat whenever the temperature went below 70 F.

He went home once when he was in college and tried to explain snow to his grandparents. They don't have any words for it in their native language, and basically thought he was making the whole thing up.