Over the last 20 years or more, I have made the observation that the snow for making a snowman only packs properly when the temperature is, in general, above freezing. This could be explained by the unique property of water, which, because it expands upon freezing, the solid phase will melt when pressure is applied. To get the snow to pack well, the temperature of the snow needs to be close enough to the melting point that a slight pressure will melt it, and then it re-solidifies in its new form as the pressure is released. Last Saturday, Chicago had a snowfall that occurred with above freezing temperatures, and I was able to build this snowman in my backyard. He started out at about 5'0", and now stands about 4'0", after a couple of days of partial melting along with sublimation has reduced his height. Anyway, I think I got the physics part correct, but it was fun making the snowman in any case. :) ## \\ ## Editing: @Chestermiller I welcome your feedback. Do I have the thermodynamics correct on this one, in regard to the snow packing much better near the melting point? :) ## \\ ## Additional editing: The explanation of the physics of getting snow to pack in this post is later determined to be most likely incorrect, with a different explanation offered by @DrClaude in post 20.
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