It's not just because people avoid venturing outside. It's also because of the properties of snow itself.
"Snow is a pretty good sound absorber," said David Herrin, an associate professor in the UK Collect of Engineering who studies acoustics.
Snow actually absorbs sound like a lot of commercial sound absorbing materials do, such as fibers and foams used in cars, HVAC systems and other equipment. This isn't all that surprising, though; snow tends to not be very dense, drifting to the ground and wrapping everything in a thick "blanket."
"In the audible range, a couple inches of snow is roughly around 6 or 60 percent absorbing on average," said Herrin. "Snow is porous, in some ways like a commercial sound absorbing foam."
During snowfall, flakes don't make any type of sound when they fall to the ground. This is especially true in comparison to rainfall.
"Rain drops, on the other hand, fall at higher velocities and strike the pavement," said Herrin. "You are hearing impact noise. With snow, the impact force is much less partly due to the reduced speed."
Next time you step outside when there's snow on the ground, make sure and listen. You'll notice that there's little in the way of loud sounds, and that's mostly thanks to the sound insulation that snow provides.
Reference:http://uknow.uky.edu/campus-news/science-behind-snows-serenity
Story via Schttp://www.scienceworldreport.com/articles/36241/20160122/physics-snow-why-quiet-outside-storm.htm
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