Silence In The Snow

Recent snowfall has offered many opportunities for photography. It has also led to a dramatic increase in avian diners, including chaffinches and starlings which I haven’t seen visit the garden for years. Snowfall brings with it a certain silence. The quiet is most noticeable immediately after snow has fallen. While the icy covering might dissuade people from following their regular outdoor routines, leading to a certain reduction in noise, there is also a science behind the silence in the snow.

Snowflakes are porous. Their ice crystal structure is formed of open spaces, which absorb sound waves. The effect is most noticeable after a fresh fall of a few inches (a light covering won’t have the same impact). Higher frequency sounds are particularly susceptible to being absorbed by snow – both while the flakes are falling, and once they have landed. The ice crystal structure is similar to commercial sound-absorbing products, such as wall panels for recording studios.

The absorption rate of sound is measured between 0 and 1. An absorption coefficient of 1 indicates sound is absorbed completely. Fresh snowfall can have a coefficient of between 0.6 and 0.9, meaning that around 60-90% of sound is absorbed. When snow melts, and refreezes, its structure changes, and the porosity decreases. Sound absorption is therefore less efficient.

Nature’s instinctive response to snowfall might be a period of locking down. But there is also a certain science behind the perceived level of silence which follows the fall. Enjoy the peace – and remember to top up food and water for the wildlife which lives around us.