A conversation from last week has got me wondering. The fellow was
reminiscing about living in Thompson (northern Manitoba) and what it was
like at -50 F (approx -45 C). One of the things he mentioned was the
snow squeeking. Afterwards I got to thinking that I've often heard
squeeky snow but hadn't given it any thought. In fact, it was about
-30 and I noticed the snow squeeked a bit as I went about that day. So
I've queried a few other people on the subject, and it seems that nobody
I know has ever stopped to really thing about it or pay much heed. The
general consensus is that it begins somewhere in the -20's. So in case
anybody here has ever looked into it:
1) is it the snow that squeeks, or is it the boots rubbing against it?
2) what is the mechanism? At some particular temperature does it lose
some kind of lubrication that normally makes it slick enough to not
squeek? I recall something about a thin water film on the surface of
ice, which provides the basic slickness. Does the snow squeek when that
film reaches some critical thinness?