The sound of footsteps comes from what happens between ice grains. Temperature and snow structure explain why winter walks do not all sound the same.
The first step leaves a footprint and a sharp sound. The second repeats it, while the surrounding landscape seems quieter than usual. This is not a contradiction: the sound produced by a boot and the way snow absorbs noise depend on different phenomena. To understand them, we need to imagine the snowpack not as a uniform block but as a structure of tiny ice particles separated by air-filled spaces.
When we put our weight on it, that structure changes. The grains move, rub against one another and become compressed; some bonds break. These small failures, repeated beneath the sole, can produce the familiar crunch of a winter walk.
Cold changes the behaviour of ice crystals
The Swiss Institute for Snow and Avalanche Research, SLF, describes snow as a material whose behaviour depends on temperature, structure and the speed at which force is applied. At low temperatures, when subjected to a rapid force, crystals and the bonds between them can fracture in a brittle way. Many small fractures occurring together produce an audible sound.
Closer to the melting point, deformation can take place more easily without the same type of fracture. The National Snow and Ice Data Center also highlights the role of friction: when grains are compressed at lower temperatures, their movement against one another encounters greater resistance. Closer to melting, this contribution decreases.
There is therefore no universal temperature at which every snowy surface begins to make a sound. The history of the snow matters too. Comparing footsteps on freshly fallen snow with those on a transformed crust is not the same experiment with only the thermometer changed.
Why the landscape seems quieter after snowfall
A fresh, soft covering of snow can absorb some sound waves. The spaces between crystals help dampen noises coming from the surroundings. If the surface melts and then refreezes, becoming smooth and hard, it can instead reflect more sound.
That is why we can hear our boots distinctly while feeling that we are in a muffled environment. Each step produces a sound just centimetres from the person walking; the surrounding snow changes how other noises travel.
During a walk, listening to this difference is a simple way to notice how much the snowpack changes. There is no need to seek out a remote place: a quiet, permitted stretch, a few steps on the snow and a comparison with the nearby surface are enough. That sound tells the story of a material undergoing change, not just a temperature. It must not, however, be interpreted as a measure of slope stability or route safety.
Read also: How snow is preserved through the summer.
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