Paul,
Thanks for expressing appreciation for my posts-BAYB! (Back At Ya, Buddy). My learning curve has increased exponentially over the last few weeks from all the information, ideas and opinions that I’ve read and conversations that I’ve been a part of. Thanks to all!
Re. the last paragraph of my last post: I’m sure formulas for heat transmision can be found in any basic physics reference publication. The following is what I was told by a physicist working at Los Alamos National Labs while I was living in Santa Fe.
Heat energy is proportional to Large Constant X Temperature Squared (this refers to conduction) + Medium Constant X Temperature Cubed (this refers to convection) + Small Constant X Temperature to the Fourth Power (this refers to radiation).
From examining this formula one can see that for low (human) temperatures, the large constant makes conductive heat loss the most influential mode of heat transmission. While the smaller constants of convection and radiation resign them to being of minimal influence. Their larger exponents are not able to express their influence at these small temperature values. The higher the temperature, the less influential the constant becomes as the power of the exponent takes over. So that as we reach high temperatures (far beyond that of the human body) with the temperature to the 4th power expressing the influence of radiation, the large constant headstart given to conduction cannot compete. And this is why reflective films are of virtually no value in keeping human bodies warm and why insulation is. P.S. Please don’t tell this to Western Mountaineering. It will only upset them.
Re. your comment on space capsules: Because they operate in a vacuum where conductive heat loss is impossible (there is no matter in a vacuum to conduct heat to) the only way to impose an effect on heat transmission is to reflect radiation -with gold foil, which can be as thin as 4 atoms thick, being an excellent tool with which to accomplish this. Additionally, since there is no atmosphere to absorb radiation in space and so many sources of radiation; radiation reflective films take on an even greater importance.
This can all be summed up by the eternal question: If there’s no sound in space…why does a vacuum make so much noise?
It is interesting to note that the manned space program is a sister science of our passion (albeit better funded). You think 40 miles/day unsupported is a daunting goal? Try escaping the pull of gravity. No really; try it! The Apollo Program’s LEM (Lunar Excursion Module) was constructed so obsessively light in order to be able to escape the Moon’s pull with minimal thrust that the astronauts could severely dent the wall of the capsule by simply punching it with their fists. Forget an overnighter without a tent. That’s exposed!
Your prohibited watershed camping story reminded me of my own 15 years ago above Vancouver B.C.’s Grouse Mountain Ski Area. My Canuck girlfriend and I hiked to the knife edge ridge defining the city’s watershed boundary to climb on an obviously named formation known as The Camel. We pitched our Chouinard pyramid tent using only rock pro and climbed as sightseeing helicopters buzzed us. I’m not sure of the legality of our encampment, but we maintained the ethics of our aerie settlement by peeing with impunity but making sure to hang our backsides over the edge into the adjoining watershed to poop and smear.
Thanks for prompting a fond scatalogical memory, Al





