What do you do in near-frost bite conditions, when your hands start numbing and you cannot even wiggle your fingers? Ans.: Pee on them! Yes, it may appear bull-shit but it is what struck me when I was (almost) about to lose my fingers due to a frost bite attack. And this happened very recently on my solo motorcycle trip to Ladakh.
I had started pretty early from Karu towards Manali to cover as much bad ground I could in daylight. I was riding alone and by the time I crossed Upshi, it started drizzling. I was covered from head to toe in multiple clothing layers and was wearing a rain coat over my riding jacket but did not adequately cover my hands. All I had were my textile riding gloves. As if the icy rain was not enough, at Talang La it started snowing (moderate). My riding gloves were completely drenched and the searing pain in my fingers increased to such a point that I actually couldn't feel anything on my fingers. Near Talang La, I wished to stop but that is when a horrifying fact hit me - I found that I couldn't move or even wiggle my fingers off the handles. No word/expression can describe the excruciating pain in my hands; when I realized that I may be on the verge of losing finger(s) due to frost bite. It was near the Talang La top and there wan't a soul around. no motorcyclists, cars, nothing. Obviously, other people had the good sense not to start in the icy rain in those dizzying altitudes.
I tried warming my hands on the bike's exhaust but other than burnt skin, I could achieve nothing. Pushed back and without any help, suddenly a flashback of a scene from god-knows-what survival series came to my mind. Somehow, I managed to zip down my jeans and peed on my hands. And voila! It worked like magic. My fingers felt a surge of blood rushing through the veins and I could at least move my fingers albeit very little. Realizing that it was my only chance to save my fingers, I gradually warmed my hands over the motorcycle's exhaust and engine (which were also losing heat very fast!) and after around half an hour of this mind-numbing ordeal, I could finally move my fingers. I couldn't afford to wear wet gloves in that chilled early morning air and therefore I wrapped up my fingers with some duct tape, creating 'wrap-around' gloves for the moment.
Moment of Truth:
I believe it was just a matter of seconds between when the idea to pee on my hands struck me and when frost bite could actually set in. After starting to 'feel' motion in my hands, it was like a machine which automatically hums back to life just after an abrupt power outage. I could actually feel the blood slowly flowing in my fingers! It was nothing like I had ever felt before.
Science behind the phenomenon:
As much as I can recall from my basic science classes at school, it must be specific/latent heat/conduction playing its part. You will know that liquids expand more than solids on heating. Moreover, expanding liquids will conduct heat on a wider surface area as compared to a rigid solid due to its fluidity. From what I could understand that instant 'warmth' was all my fingers needed and not high heat focussed at a particular part (me touching the exahust and had burnt my finger). It is for the same reason, putting your hand in hot water scalds a larger area even if the contact is for fraction of a second as compared to touching a hot solid body. It follows that you will be scalded almost immediately by steam than water/solid at the same temperature.
The specific heat capacity of a material measures how much energy is required to change the temperature of that material. The specific heat capacity of water is 4180 joules per kilogram per kelvin, meaning that it requires 4180 joules of energy to raise the temperature of one kilogram of water by one kelvin.If a one gram drop of boiling water (at 100°C) falls on skin at a temperature of 35°C then the temperature of the water quickly falls by 65°C. To drop the temperature of one gram of water by 65°C requires a change in energy of 272 joules. Because heat always flows from a hotter body to a colder one* this heat flows into the skin, damaging skin cells as it does.