Right now it's a bit chilly in the upper midwest (-21 degrees this morning at 6:00 am; -23 degrees predicted for tonight). When walking our dog this afternoon, my wife and I noticed that the snow underfoot squeaked louder that usual. We observe that snow makes a qualitatively different sound depending on temperature with the most noticeable squeaking starting at about -10 degrees. (All degrees in this post are Farenheit.) Why should the sound made when walking on snow depend on temperature, and why should it appear louder the lower temperature?