Snow Physiological Thermodynamics

Snow Physiological Thermodynamics

Ah, life. Another snow dump in the last week of February, another trek in the woods behind my cabin on the Brushy Mountain. Christopher Robin would call it the 100 acres woods - the magical place where his child's imagination can run free, and where his best friend Pooh Bear lives in a hollow tree under the name of Mr. Sanders. I call it Dr. John Bennett's semi-wilderness tract, the magical place where I can recreate and nobody lives except my friend Mother Nature.


I chose to cross country ski today, which is usually problematical for me. Unless you have near-perfect conditions, such as in Vermont with super cold, dry snow on machine groomed tracks, cross country performance falls off. X-c skis are kind of delicate, and don't like steep hills, heavy snow or changeable conditions. Today the snow was too deep, wet and unconsolidated. The skis tended to build up a compressed base of snow, and then fall off to the side. Or an island of snow clumps would build up in front of my feet and slow me down. Fortunately, my recent telemark experience out west has improved my balance and springiness, so I was able to make a go of it. It was fresh and invigorating. I saw some deer tracks.

So what about the physiology? I grew up in the rural, southern town of Taylorsville. It is far enough north and close enough to the Blue Ridge Mountains to get decent, dependable snows. But it is far enough south and in the Piedmont for the Board of Education to be buffaloed by snow. Whenever we got an inch or more, we got a vacation. I spent much of my winters playing outdoors in the snow, in the pastures all over the farm where we lived. We sledded, made ice rinks, sledded, made hay bale forts and had snowball fights, sledded and made snow cream. Did I mention that we sledded?

Sometimes my wonderful Dad would make a wood toboggan, or bring home some inner tubes, or even a car hood. Then we would invent new ways to slide down the hills in the pastures. Other times, he would bring home a new metal runner sled (cool!). Many times I rode a sled down the long hills standing up, like a Hawaiian king on his surfboard riding a big slow wave, dreaming of the time when I could be big enough to ski.

So what about the thermodynamics? Well, as kids, who cared if we got too hot? We would just sweat. We did not wear glasses that would get fogged up. Who cared if we got too cold? We could be inside in 5 minutes. There our wonderful mother would make us hot chocolate, or snow cream, or let us sit on the heater vents.

As I have gotten older, I have discovered that when I first go outside into the snow, there is an imbalance. My body still has a reservoir of heat from being indoors for many hours, plus the excess insulation from all the clothes, plus the effort to gathering and putting on all the gear. Yet, my body reacts to the shock of the newly introduced cold air by shutting down the capillaries in my hands and feet. Then the heat has nowhere to go except to make my torso start pumping sweat into my clothes and steam up my neck. No more dry clothes (bad) and no more vision (worse). Yet, contradictorily, I am standing there with hands and feet so cold that they are getting numb. What gives?

I do not think that my physiology has changed that much since childhood. I am simply more aware of the factors. One of the first lessons in the Old Testament is that the knowledge of good and evil is the greatest sin. I don't believe that we can have too much outdoor knowledge. But we can worry too much about what we know.

So what is the cure? Behave like Christopher Robin. Be a kid. Have fun. Shut up and play. Eventually, in about 30 ' 45 minutes, our bodies will get the picture that it can safely open all the capillaries. Our hands and feet come to thermodynamic par with our torsos. And we go ski! Ah, life.

Bob Laney

Written by:

Bob is the site curator and writer of Blue Ridge Outing. Since starting the Blue Ridge Outing travel blog in 2002, Bob has written, recorded and documented countless expeditions in the US and around the world.