I watched an old Bear Grylls episode about Siberia and he mentioned that the cold can kill you “in minutes”, although he didn’t elaborate much on how and under which conditions. I suppose that he meant if you aren’t moving and/or lack enough clothing. So, is that an over exaggeration or is it true and if true, how exactly does it happen? Does your entire body freeze when it’s freezing enough or maybe just lungs or something, which in turn prevents air from reaching your brain?
A lot of mountaineers, homeless people, refugees and so on lost their lives due to this, but I am not sure exactly how it all happens.
“Freezing to death” is not actually an accurate term. You’ll be dead long before any part of your body except the extremities (hands, feet, nose, ears) freezes.
The cause of death due to cold temperatures is hypothermia. You lose heat from your body so fast that your metabolism can’t maintain a normal body temperature. Once your core body temperature falls too low, your heart and brain will cease to function and death results.
So…essentially, the main cause is the same cause as with inhaling smoke or drowning: the lack of air for the brain, which destroys brain cells? If so, then that’s one hell of a round trip of actions&effects that do the same thing.
Chemistry explanation which shows that a 10 deg temperature change results in reaction rates being about 1/2 (or double if temp increase). So think of glucose metabolism, which involves >10 rxns, once you slow each of them by 1/2 you suddenly have nearly no energy being created in the cells (1/2)^10 = 0.09% efficiency!!!
But also oxygen transport, requires at a minimum oxygen going into the lungs and then 1. across the air water membrane 2. getting uptaken by heme 3. offloading from the heme and 4. uptake by cells. This is a gross oversimplificaiton but each of these chemical+physical reactions will slow and literally the cells starve out of oxygen.
So while 10deg C is a lot, even 2 degrees F across so many reactions really messes up metabolism.
As you get cold, you start to shiver (your body’s attempt to warm yourself up a bit), and your blood vessels constrict. The body basically tries to keep the core of your body warm, at the sacrifice of your extremities. You can easily end up with frostbite and permanent damage to your fingers and toes at this point.
As you continue to get colder, you start to lose the ability to think clearly, and you become clumsy and uncoordinated. This is because the nervous system is starting to shut down. Other organs are starting to shut down as well. The lack of clear thinking can lead to very disastrous results. Some people engage in burrowing behaviors, which is kind of a “hide and die” response. They’ll tunnel into snow or find a corner to crawl into, where they are eventually found, dead.
Some people will undress. It’s not exactly clear why this happens. Some people think that the body’s temperature regulation is so far out of whack at this point that the confused person actually feels hot. It might also be that the blood vessels lose their ability to constrict due to the nervous system shutting down, and the sudden rush of blood to the extremities makes them feel warm all of a sudden.
As the nervous system continues to shut down, you become more and more confused and unable to control your body’s motion, and eventually you lose consciousness. At this point, it’s now a race to see what kills you first. Your organs might shut down, causing death, or your heart may go into arrhythmia, killing you before your organs completely fail. You might end up brain-dead before your body completely dies. Dying isn’t a switch. You’re not on or off. Dying is a process and it takes a while for everything in your body to die.
As an example, there is a very famous case of a skier who had her head underwater in near-freezing temperatures for 80 minutes, and survived. Fascinating story.
Hence the need to check the box on your driver’s license where it says you want tobe a tissue/organ donor so your tissues and organs can go to someone who needs them. They stay viable for quite some time after you no longer need them.
I knew a fellow whose son died of exposure. They lived in northern Canada, and one night in the dead of winter when it was -40 out, four guys decided after a party to go 4-wheeling cross country in their Jeep. Not a clever thing to do in sneakers and jeans and a not-very-thick coat. They got stuck in the snow or had a flat tire or something. Two decided to walk back into town for help, the other two stayed behind and tried to dig out the jeep. From what they can tell, they eventually burned one of the tires to try to keep warm. One guy almost made it home, a taxi driver found him wandering the town and took him to the hospital. He lost a few toes and maybe some fingers, I think. The other died when he couldn’t get up the bank of the river at the edge of town. The other two froze at the jeep.
There was also the case out west in Canada of the little girl who followed her father out the door when he went to work one morning. She was found almost dead hours later, and lost parts of 3 limbs and her hands to frostbite IIRC.
But basically, there’s a form of hypothermia where at a certain point you are not thinking straight, where cold feels like burning heat and the victim will take of their coat etc. to try to escape the burning - which does not help the situation. Before the brain stops functioning, the usual deprived brain symptoms can appear - inability to think straight, to understand the situation, etc. At a certain point numbness and inability to move sets in, and the person loses consciousness. Of course, If they find you and try to revive you, there’s a good chance freezing - frostbite - has destroyed tissues and the body part, usually the extremities have to be amputated before gangrene sets in.
I have heard freezing to death is relatively painless. But I’ve also read an account where two people froze to death in a car stuck in the middle of nowhere during a storm and left some writings behind. In them, they wrote that freezing hurt a lot. Which is true?
It depends. If youget hypothermia while unconscious, it doesn’t hurt. But if you’re conscious and managing to stay semiwarm… have you ever had chillblains? Think of having them all over your hands and feet.
Stuff like the jeep story seems weird to me, I wonder how cold it was. It seems like as awkward as it might feel that 4 guys getting as close as they could to one another could generate enough heat to stay alive, I wonder how cold it has to get before it’s not possible for a small group of people like that to die.
Here’s a similar story about a girl in Minnesota in the 80s who was found literally frozen solid like a popsicle and survived with no long term effects:
Our company did a project on the North Slope (Alaska) many years ago. At -40 deg F (which is also -40 deg C, incidentally), if you take a cup of coffee and throw it into the air, it is so cold that the coffee freezes into a “coffee snow cloud” and blows away in the wind. It doesn’t hit the ground.
-40 is really fricken cold.
Sad story about the guys in the jeep. If they had tunneled into the snow and made a snow cave of sorts, their body heat might have kept them alive, but exposed to the air, they probably didn’t stand a chance.
