Want to eliminate noise pollution? Let it snow
With snow comes silence … literally.
A study by the University of Kentucky (UK) found that just a couple of inches of snow can absorb as much as 60% of sound as snow can act like a sound-absorbing foam — especially when snow is fluffy and freshly fallen.
Seattle averages 6.3 inches of snow per winter, with the city seeing the first couple of inches earlier this week.
“Snow is porous, in some ways, like a commercial sound-absorbing foam,” wrote David Herrin, an Associate Professor at the UK College of Engineering.
Even heavier snowfall makes relatively little noise because snowflakes are filled with air which makes them drift slower to the ground — unlike rain.
“Raindrops fall at higher velocities and strike the pavement. You are hearing impact noise,” Herrin wrote. “With snow, the impact force is much less, partly due to the reduced speed.”
There are other reasons for the lack of noise each time snow falls. Snow keeps people home, leaving fewer pedestrians and cars in public spaces.
Birds tend to hibernate and nest during severe weather as well, creating less noise during snowfall, according to the National Audubon Society.
As snow melts, it loses its ability to silence its surroundings because the snowflakes change shape as they melt, reducing the size of the spaces, or air, between the crystals. In Seattle, newly fallen snow melts nearly on impact. Once the snow becomes ice, surrounding noise is actually amplified due to sound waves reflecting on ice rather than absorbing them, according to the Michigan State Extension.
As temporary as snow is in the Puget Sound area — King County averages approximately 3.9 days of snow a year — the reduction of sound snow creates is even more fleeting, making it an even more special occasion.