Wikipedia:Reference desk/Archives/Miscellaneous/2014 September 26

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September 26

Hot vs. cold

Other things being equal, where would a person survive for longest, in the hottest place on earth (Death Valley, say) or the coldest place on earth (Antarctica, say)? Thanks. --Viennese Waltz 12:38, 26 September 2014 (UTC)

Really question, I'm interested to see responses. I do recall people locked in cars on a hot summer day dying within hours, and on the other end of the spectrum, folks running around in icy places (Antarctic Ice Marathon i think?) wearing only a pair of trouser bc they could self-regulate through meditation; i'm aware of meditation helping increase body temperature in cold conditions but not lowering body temperature in hot conditions so i think a person survive longer in the colder place but i am by no means an authority figure these are just my two cent sorry ~Helicopter Llama~ 13:24, 26 September 2014 (UTC)

I don't see how we can answer that question without more information. The requirements to survive in each place are not the same. Do they have any shelter? That would make a huge difference. How much food, water, equipment do they have with them? If other things are equal does that mean they are wearing the same clothes? If so what are they wearing?--Shantavira|^{feed me} 13:47, 26 September 2014 (UTC)

Sigh. That's why I said "other things being equal". Why do people have to make simple questions more complicated? Yes, they are wearing normal street clothes which are suitable for a temperate climate – a Hanes T-shirt, a light brown jacket and a pair of chinos from Gap. They have enough food so that they're not going to die of starvation. --Viennese Waltz 13:53, 26 September 2014 (UTC)

It's a really tough question because, all things being equal, things still aren't really equal. We are talking about how the human body reacts to extremes of heat and cold, and the specific body type would have an impact on that. (E.g. An obese person person could do better in the cold than a skinny person, while the opposite might be true if it were hot.)

Adding to the difficulty, this isn't an area where properly controlled experiments can really be conducted. (Well, at least not by ethical researchers.) When someone is found who has died of hypothermia or hyperthermia, it isn't easy to tell how long they had survived. And if they aren't dead yet but succumb during treatment, it isn't possible to tell how long they would have survived without treatment.

All that said: based on some light reading in the area (including the above two articles plus some cheerful Googling of "death hypothermia", "death hyperthermia", etc.), I'd say our hypothetical Gap-wearing victim would die first in Antarctica. People routinely freeze to death overnight when the temperatures fall below 0C; at Antarctic temperatures with no shelter or warm clothing it would be almost impossible to survive more than a few hours. Conversely, rapid deaths due to heat only seem to occur when victims are in enclosed spaces (especially cars) that reach temperatures higher than even the hottest places on Earth. When people die during heat waves, it seems to take a couple of days. 105C in Death Valley would eventually kill our guy, but if he was reasonably hydrated to start with he'd probably last a few days.

Paradoxically, of course, more people die from heat waves than cold snaps. It is easier to stay warm than it is to cool down, assuming one has some shelter and resources beyond the clothes on one's back. - Eron^Talk 14:37, 26 September 2014 (UTC)

Most people will survive longer in the hottest place on earth, which would be either the Sahara Desert or Death Valley. In both places highs of 50 degrees Celsius (122 degrees Fahrenheit) or more are common during the summer. However, both places have quite low humidity, so with plenty of water and salt most healthy adults could survive for a fairly long time. Survival will be aided by maintaining a low level of activity and seeking any shade that may be available. In contrast, the coldest parts of Antarctica get as cold as -90 degrees Celsius (-130 degrees Fahrenheit), and we're assuming that our victim has only a light jacket for protection against hypothermia. Death will follow in short order. John M Baker (talk) 14:45, 26 September 2014 (UTC)

Now, during the Messinian salinity crisis, when the Strait of Gibraltar was closed and the Mediterranean Sea evaporated except for a few brine lakes, it is thought that temperatures would have got as high as 80 degrees Celsius (176 degrees Fahrenheit). That would have killed quite quickly, perhaps even more quickly than the Antarctic cold. But there is nothing like that on the surface of the earth today. John M Baker (talk) 15:01, 26 September 2014 (UTC)

Why would it have gotten so hot, User:John M Baker? Because of the increased air pressure? μηδείς (talk) 17:04, 26 September 2014 (UTC)

More greenhouse effect would certainly do it, due to more greenhouse gases in the air. StuRat (talk) 17:09, 26 September 2014 (UTC)

Basically, the earth gets warmer the deeper you go, and the air above it would have been heated by convection.

As I look more closely at our article, I notice that there are no citations in the section on Messinian salinity crisis#Relationship to climate, which seems to be original research, so I don't think I can stand by the specific numbers cited above. However, if anything I suspect that the bottom of what is now the Mediterranean Sea would have been even hotter. The writer of the article based his or her estimates on the dry lapse rate of atmospheric cooling, which is about 10 degrees Celsius per kilometer. However, it's probably more relevant that the geothermal gradient reflects increases of about 25 degrees Celsius per kilometer of depth as you go into the earth. In any case, I feel sure that the desiccated Mediterranean Sea bottom would have been extremely hot. John M Baker (talk) 17:44, 26 September 2014 (UTC)

I was looking at PV=nRT where the increased air pressure itself, a mile below sea level, would be hugely influential. The fact the crust is hotter the deeper you dig wouldn't seem relevant, since the crust was not actually duggen, and there would have been plenty of time for it to cool, especially that the evaporation of the mediterranean would have been a coolative process. μηδείς (talk) 20:56, 27 September 2014 (UTC)

The hottest air temps (excluding things like erupting volcanic calderas) on Earth could be survived for hours, while the coldest temps, only minutes, unless the person in the cold area was able to quickly bury himself in snow. If he could do that, then his body heat would warm the surrounding snow to 0°C, and he might be able to survive for hours then, too. Getting air without letting the heat out would be problematic, though. There are devices for that, but he presumably wouldn't have those. The man in the desert might want to remove his clothes and use them for shade, instead. (An exception would be if his clothes were white and he had dark skin, then they might do him more good if he kept them on.) Also, if the man in the desert could find water, he could probably survive indefinitely. Of course, this is no easy task in a desert. StuRat (talk) 17:15, 26 September 2014 (UTC)

. Please note that by saying that, I have not said you are wrong. What I am saying is that you need citations or references for claims you make. Even the ones which are correct. --Jayron32 17:17, 26 September 2014 (UTC)

One principle of treating hypothermia victims is that "you aren't dead until you are warm and dead." With that in mind, as long as our man stayed in the Antarctic, he'd be effectively immortal. - Eron^Talk 18:27, 26 September 2014 (UTC)

Not quite. That only applies to low body temperatures where the body core remains above freezing. Once you are frozen solid, you are dead, as the cells rupture when the ice crystals form. There are some simpler life forms which are able to survive freezing (or apparent freezing), but humans lack their adaptations. Also, even with hypothermia above freezing, the body will still die eventually, if kept cold, since hypothermia only slows the processes leading to death, it doesn't stop them, just like food in the fridge still goes bad, it just takes longer. StuRat (talk) 18:50, 26 September 2014 (UTC)

So much for my plans for an icy eternity - Eron^Talk 21:23, 26 September 2014 (UTC)

I notice you've chosen to ignore Jayron32's excellent point in response to your previous post. --Viennese Waltz 18:55, 26 September 2014 (UTC)

As I've stated on numerous occasions, I'm willing to provide refs for statements which seem difficult to believe, but not for statements I make which are blatantly obvious. I made like a dozen statements in that section, most of which are quite obvious, and I have no intention of wasting my time proving the obvious. If Jayron has a specific claim he wants me to prove, then let him ask. StuRat (talk) 22:31, 26 September 2014 (UTC)

Wikipedia policy says that you need references for facts that are not obvious, or which are likely to be contentious...so indeed, you don't need to dig out references for every single thing in and article. Moreover, the Ref Deck isn't considered to be an 'article' so reference requirements are not even that strict.

Here's a reference on cold survival: Predicting survival time for cold exposure: "The prediction of survival time (ST) for cold exposure is speculative as reliable controlled data of deep hypothermia are unavailable." They did their best, though, and the abstract goes on to suggest a variety of predicted survival times, e.g. a range of 4 to 15 hours for temperatures from −50° C to −20° C for an average healthy male with two layers of clothing. A survival time of "minutes" in cold weather is far too short unless the person is immersed in cold water. - Eron^Talk 22:44, 26 September 2014 (UTC)

That's far from the coldest temperature on Earth. According to Lowest temperature recorded on Earth, the lowest recorded temp is -89.2°C, and I suspect that the actual coldest temp is considerably lower, since thermometers aren't very widespread in Antarctica. You also have to consider winds. Antarctica has major winds, and I suspect your link doesn't account for wind at all. The lowest recorded wind chill factor is -124°C: [1] (warning, annoying ads at that site), but again the actual lowest wind chill factor is likely far lower.

So let's just do a back of the envelope extrapolation. If the 30°C degree temp drop from -20°C to -50°C decreases survival time to 4/15ths, and we assume the actual (unrecorded) coldest wind chill to be -140°C, then we need 3 more of those drops to get there. So, 4 hours × (4/15)³ give me less than 5 minutes survival. You're welcome to try your own extrapolation using your own assumptions. StuRat (talk) 23:03, 26 September 2014 (UTC)

All that may be true. But I managed to find a link to a reputable source that was actually attempting to answer the question of how long people really can survive in the cold - which as it turns out is a very difficult question to answer. You, claimed, earlier, a survival time of "minutes". No sources I have been able to find bear that out, even accounting for temperatures below -50 and wind chills. The survival range, assuming one is dry and clothed, is in the range of hours, not minutes. (BTW, the study I cited did include wind; I didn't quote it for the sake of brevity. The figures I quoted included wind at 5 km/h. Yes, a light breeze, but far from "not account[ing] for wind at all." If you are going to dismiss my references, do me the courtesy of reading them first.) - Eron^Talk 23:18, 26 September 2014 (UTC)

I missed the slight breeze they used, but that wouldn't change the numbers much. I am using refs (yours plus mine), and extrapolating from yours, since yours is wholly inadequate alone. (I got an edit conflict on adding the extrapolation above.) StuRat (talk) 23:27, 26 September 2014 (UTC)

"The actual lowest wind chill factor is likely far lower." See that, that right there? That is you pulling an answer out of thin air. You are basically just making stuff up. So kindly refrain from dismissing other people's references as "wholly inadequate". At least we bother to find them. - Eron^Talk 23:49, 26 September 2014 (UTC)

What are the chances that, wherever on Earth the lowest wind chill happened to occur, there just happened to be a weather station at that exact point ? Pretty damned low. But, if you want a more conservative estimate, let's just drop the temp 60°C degrees from your -50°C (plus 5 km/hr), to get 4 hours × (4/15)², or 17 minutes. And note that declaring the survival time at -50°C to be the same as at the coldest temperature on Earth is "making things up", and doing a profoundly poor job of it, too. StuRat (talk) 23:58, 26 September 2014 (UTC)

Lucky for me, I never declared that -50 was the coldest temperature on Earth. Nor did I attempt to accurately predict survival time at that hypothetical lowest temperature. I simply quoted, and provided a link to, a scientific study on estimated cold weather survival times. - Eron^Talk 00:03, 27 September 2014 (UTC)

You said "A survival time of 'minutes' in cold weather is far too short unless the person is immersed in cold water." Since you were referring to my statement, which was a reply to the OPs Q about the coldest temperature on Earth, you were applying info on -50°C to conclude that my statement on the coldest temp on Earth (at least -124°C wind chill) was wrong. Your study is simply not applicable to my statement, unless you at least attempt to extrapolate from the temps in the study to the actual temps we are talking about. StuRat (talk) 00:22, 27 September 2014 (UTC)

Sure thing. Whatever you say. - Eron^Talk 00:24, 27 September 2014 (UTC)

According to our article on Antarctica, temperatures reach a minimum of between −80 °C (−112 °F) and −90 °C (−130 °F) in the interior in winter, with typically moderate winds. So let's say a temperature of −80 °C. According to Eron's source, with two layers of loose clothing (average thickness of 1 mm each) in a 5 km/h wind, survival times are 4.0, 5.6, 8.6, 15.4, and >24 h for −50, −40, −30, −20, and −10° C. So the clothing is more or less comparable to what we are assuming, and perhaps the wind speeds are too, but the temperatures are not as extreme. Note that the drop from -20 to -50° C resulted in a drop in survival times from 15.4 to 4.0 hours. We can assume a further significant drop in survival times as the temperature drops to -80° C. The survival time will certainly be less than 2 hours and might be less than 1 hour. It will, however, be more than just a few minutes. John M Baker (talk) 23:59, 26 September 2014 (UTC)

I didn't use the word "few". And note my source which listed the coldest wind chill as -124°C. Also let's see some math, please.

Let me redo my math using the latest info you provided: 4 hours × (4/15.4)^(124-50)/30× (60 mins/hour) = under 9 minutes. Note that this is with the conservative (and dubious) assumption that the coldest recorded wind chill is also the coldest actual windchill. StuRat (talk) 00:07, 27 September 2014 (UTC)

• Can we just point out that the issue is shelter versus evaporative cooling? Someone with no shelter at -40 degrees is going to freeze to death rather quickly, because their lungs will freeze and cease to function after a few minutes. Adequate shelter will prevent that. Someone unsheltered in Death Valley on the hottest day will die within an hour or two as their core temperature rises. But given a mild low humidity breeze an unlimited supply of water, they will survive indefinitely. With no shelter or water the comments about antarctica being a quicker death are correct. μηδείς (talk) 21:47, 27 September 2014 (UTC)

I agree that extreme cold kills you faster - but our OP is perhaps being a bit generous with the hot side of things. An ungodly amount of heat - but with very little humidity is survivable because sweat evaporation does a great job of cooling us down. However, if you get somewhat less heat - but 100% humidity, then sweat can't evaporate. If the temperature is above body temperature, then wind doesn't help to cool you off either - and can actually make matters worse. So Death Valley may not be the worst case scenario here. Think of someplace both hot and humid. SteveBaker (talk) 21:55, 27 September 2014 (UTC)

@Medeis: could you please explain your last comment? How long have I been dead and how is it that I am able to operate semi-normally with lungs that have, apparently, been frozen several times over the last 40 years. Also can you give a reference for the sentence that "Someone with no shelter at -40 degrees is going to freeze to death rather quickly, because their lungs will freeze and cease to function after a few minutes." I've lived in Cambridge Bay for 20 years now and in Ulukhaktok for 19 years before that. The coldest I have experienced was in Ulukhaktok in February 1985 when I recorded a temperature of −49.0 °C (−56.2 °F). I would have also recorded the January, −47.5 °C (−53.5 °F), and March, −45.0 °C (−49.0 °F), as well. Several times a winter I will have to make a 15-20 minute walk to the work site because the road is blocked from a blizzard. At least one of these walks will be at temperatures below -40. And no, I don't wear one of these as I find them annoying and uncomfortable. CBWeather, Talk, Seal meat for supper? 05:19, 28 September 2014 (UTC)

No, I won't. The premise is standing outside in a Haines T-shirt at 40 below. That also assumes you are not a fat Inuit jogging in place. If you can do that walk naked, bully for you, but I am not required or disposed to disprove your magical abilities when exposed skin at that temperature is know to freeze within minutes. Also, for some reason, your ping didn't work, that's the second time I have noticed that recently. μηδείς (talk) 05:31, 28 September 2014 (UTC)

"Their lungs will freeze and cease to function after a few minutes". - Eron^Talk 06:14, 28 September 2014 (UTC)

The coldest it usually gets here in Detroit is about −20 °C (−4 °F), but that's cold enough to burn my lungs. You must be more tolerant of low temps than me. I do indeed need to wear something like that outfit in our coldest conditions (but the part covering my mouth quickly clogs with ice, so I use a scarf instead, which allows me to move the ice-encrusted part away, several times, before the entire scarf is ice-encrusted). At the temps you describe, I think I'd need to add the intake tube wrapped around my body to preheat air with my body heat before I inhale it. StuRat (talk) 05:34, 28 September 2014 (UTC)

Standing outside or walking around in a t-shirt at 0 °C (32 °F) will kill you never mind the -40, see hypothermia. But -40 will not freeze your lungs, standing or walking. There is a big difference between freezing your lungs and freezing exposed flesh, which can happen quickly wind chill in F and wind chill in C. Unless your lungs are on the outside of your body there is no way that they are going to be exposed to -40 temperature. I never mentioned jogging, just walking, and I have no idea if running would make a difference. So I expect that StuRat is more sensitive to the dryness of the air, which will cause a burning sensation in your lungs. I have no magical abilities to stay warm but you have been one of the more vocal people requesting that statements be backed up with references. Yet now when your statement is questioned you decided that racist ignorant insults are better. Oh and I'm neither fat nor an Inuk. There is a lot of stuff out there on freezing lungs but I'm not sure how relilable they are but this seemed to have the best answer. CBWeather, Talk, Seal meat for supper? 07:09, 28 September 2014 (UTC)

I'd like to clarify that I didn't mean or say that the lungs would freeze solid, but air entering the respiratory passages at a raw 40 below will start causing frostbite (frozen tissue) rather quickly, and breathing trouble will get you in minutes. talk of breathing through scarves and anoraks is not relevant to the OP's specifications, neither is suddenly burying oneself three feet deep for protection. I did strangely enough get that ping a few hours after I posted last night. μηδείς (talk) 16:11, 28 September 2014 (UTC)

"Air entering the respiratory passages at a raw 40 below" will not cause frostbite or frozen tissues in the airway or lungs. But don't take my word for it:

"'Cold air has long been implicated in exercise-induced bronchoconstriction, an asthma-like narrowing of the airways that leads to shortness of breath and coughing... In these cases, though, it's the dryness of the air, not its temperature, that triggers the response,' says John Brannan, a researcher at McMaster University's Firestone Institute for Respiratory Health in Hamilton... 'No matter how cold and dry the outside air is, it will be at body temperature and near 100-per-cent relative humidity by the time it reaches the alveoli in the lungs,' says physiologist Kenneth Rundell."

From "Will I freeze my lungs by exercising outside in the cold?," - Eron^Talk 18:40, 28 September 2014 (UTC)

Beef Novgorod style

On Wednesday, I ate a dish called "Beef Novgorod style" for lunch. It was really good. It was basically a thick, juicy, well done beef steak lightly breaded with rye, covered in a sauce made of sour cream and onions, accompanied by a thick pancake made of slices of garlic potatoes, and a whole roasted garlic. Is this any famous dish or was it invented by the restaurant? JIP | Talk 17:25, 26 September 2014 (UTC)

Sour cream gravy and beef dish makes me think of Beef Stroganoff, but the potato pancakes are a unique addition. Such pancakes are well known in Eastern European cuisine. --Jayron32 17:29, 26 September 2014 (UTC)

It was not cut into pieces like Beef Stroganoff, it was a thick slab of well roasted boneless meat like a normal steak. And my choice of words was rather poor, by "potato pancake" I meant a pancake made of slices of potato pressed together to resemble a pancake, not an actual pancake made of ground potato. JIP | Talk 17:33, 26 September 2014 (UTC)

If it was a breaded beef steak, that would be a type of schnitzel or escalope or scaloppine. Schnitzel#Russia lists one such Russian dish; no idea if it applies. Wiener Schnitzel is popular in many places, and is the basis for dishes such as country fried steak in the U.S. Sliced potatoes in a pancake form are common in some types of gratin, such as Gratin dauphinois (called "scalloped potatoes" in the U.S.). Our pictures show a more casserole-style version of the dish, but I've had it where it was a single layer of potatoes. I did a search for "beef novgorod" on the internet and found bubkis. But it sounds like a tasty dish. --Jayron32 17:53, 26 September 2014 (UTC)

Note that "latkas" is an Eastern European name for potato pancakes, although that may not be quite what you had. (I knew a Yugoslavian family which called them that, back when there was a Yugoslavia.) StuRat (talk) 18:56, 26 September 2014 (UTC)

I'd always thought that latka was a Polish word but was surprised that a Polish friend didn't know what I was talking about - I think it's Yiddish. The Polish name seems to be placki ziemniaczane.[2] Alansplodge (talk) 20:31, 26 September 2014 (UTC)

Latka redirects to Potato pancake, where I read that "latka" is used by the Jewish community. I can't read Hebrew, so it may also apply to Yiddish and Hebrew speakers. -- Jack of Oz ^{[pleasantries]} 20:51, 26 September 2014 (UTC)

It's Yiddish, and it's latke - Eron^Talk 22:47, 26 September 2014 (UTC)

Hmmm ... seems to be more than two Latkas, so I'll rustle up a dab page. Thank you very much. Clarityfiend (talk) 13:37, 28 September 2014 (UTC)

Another hmmm.... The Jewish Post & News seems to think it's "latka"; see Bloom's lives on it's reputation about Bloom's restaurant in Whitechapel. Perhaps it's a Cockney-Yiddish hybrid. Alansplodge (talk) 20:01, 29 September 2014 (UTC)

OES has it as latke, Forms: Also lutka, lutke, Etymology: Yiddish, < Russian látka a pastry DuncanHill (talk) 20:14, 29 September 2014 (UTC)

Getting back to the OP's meal...it sounds very much like pommes Anna. --NellieBly (talk) 20:17, 29 September 2014 (UTC)