Serious question about a non-serious subject, asked just because it really has me stumped.
So, suppose I’m walking through the woods in the winter, and I’m freezing to death. I have maybe an hour before I collapse and die.
But I really have to pee.
So, I take a piss. That’s a whole bunch of 98.6 degree ‘water’ lying in the snow. It would seem at first thought that it’s a waste of heat, and I should do something other than pee in the snow. I mean, those are precious degrees lying there!
So, an alternative would be to piss in a canteen, and keep the now-warm canteen against my body as I walk, thus keeping me alive for a little longer.
But would it really keep me alive a little longer? What’s the practical difference between the piss being in my bladder, and being in the canteen? When it’s lying in the snow, it’s not warming me, but then, it’s also not contributing to my mass that needs to be warmed. So while it was in my bladder was it providing heat, or leeching heat?
So- will I survive longer by pissing in the snow, pissing in a canteen and keeping it with me, or holding it? Are some or all of these equal in heat conservation?
Yeah, that’s another possibility! I’m torn between that being the best solution, or if the piss in my stomach just becomes more weight my body has to expend calories to heat, though.
It is mostly just an issue of distribution of the thermal energy. If the canteen were strapped to the back of your neck and strongly insulated from the outside cold, the redistribution of heat to the arteries going to the brain would probably help more than having that heat in the bladder. It really depends upon which parts of your body would need the heat most before you died.
I would piss in the canteen, find a cabin with some people in it, ask them if I could come in and keep warm, and if they said no, I’d sling the piss in their faces, beat and tie them up and then sit by the fire and enjoy a nice cup of their hot chocolate. If they don’t have any more hot chocolate, then I would continue beating them until they got some.
Human bladders vary in capacity but research seems to indicate that a 500ml capacity is reasonable. Although the peeing urge kicks in before the bladder is full.
Let’s assume 500 grams of water will be expelled.
Let’s assume a fairly light person weighing 70kg.
Let’s also assume that you are correct and that you will last 1 hour (60 minutes) if you weight 70kg.
Then the question is how long will you last if you only have to heat and move 69.5 kg of body weight?
Assuming a constant energy loss over the 60 minutes. The total energy lost will be proportional to the time multiplied by the mass : 60min x 70kg will equal 'survival time at lighter weight ’ x 69.5kg
Solving for time in the equation : 60x70='survival time at lighter weight’x69.5
This gives a ‘survival time at lighter weight’=60.43 minutes or 60 minutes and 26 seconds.
As James said, it may be advantageous to pee in a canteen and use that captured energy to heat a specific part of the body. However, the canteen isn’t much different from an internal bladder … it is still weight which is being carried and it is still being heated by body energy. So peeing in a canteen doesn’t really help you.
That’s my thought, that your body is working to keep the pee warm. But it still seems wrong that throwing that 500ml of very warm water away into the snow when you’re freezing is the right course of action.
Sadly this would leave your lower extremities covered in a liquid which would cool rapidly, eventually this liquid would end up freezing, and then you’d most likely end up dying or being more likely to die. Seriously guys don’t piss yourself in cold conditions, generally liquids especially ones full of electrolytes or “ammonia” like substances are not good insulators, they will conduct. Generally if your bladder is full of urine, it’s very hard not to pee, sooner or later you will wet yourself, as a general rule then using the heat from your canteen against your core body, ie any blood rich system as already said will be better than pissing yourself, or indeed eating yellow snow, which as we all know is a bad idea.
The good news is if you are in the desert you can drink your urine up to 3 times before it becomes toxic, which is nice.
Clearly it is wrong, your common sense is right, this is the difference between people who die in extreme environments and those who are found and live. Never underestimate the value of common sense.
