Getting your Trinity Audio player ready...

By Kelly Bahl

Outreach Naturalist

If someone were to ask you what sound you associate with winter, would it be the joyful ringing of sleighbells? Perhaps the distant sound of Christmas music? Or maybe the quietness of a snowy morning that fills you with tranquility as you sip your morning coffee? While there are a lot of sounds that we humans provide at the pinnacle of the winter season, there are many noises that nature produces that are spectacular and can only be experienced in the winter.

Any sound that you hear is just the production of a vibration that travels through the air. Those vibrations are felt by the inner workings of our ears and our brain sorts out the rest. Wintertime has its own category of sounds you can experience.

A fresh snowfall will quiet the world down. Snow is a porous material, meaning it is full of tiny spaces. Those spaces allow for sound vibration to be slowed or stopped so ambient noises such as cars, wind, roadways, are almost entirely eliminated. One of the only things you can hear is the crunch of snow beneath your footsteps. The porous snow has excess space meaning it can be compressed or squished down. When a foot pushes down on the snow and compacts, the ice grains rub against each other creating friction and in turn, sound vibrations (aka, the crunch). The colder the temperature is, the harder the ice crystals are and therefore the louder the noise. However, the crunch of snow only starts once the temperature is around 14 degrees. Any warmer than that and the snow will start to melt with the pressure and friction, making them slosh together and reducing friction and taking away the satisfying crunch.

Seeing as Minnesota is the land of 10,000 lakes it would not be hard to find yourself near one at some point over the winter. A combination of the right weather conditions and excellent timing can produce a puzzling audio performance. The sounds that a frozen lake can produce can only be described as otherworldly. Full, bass filled notes, followed by a sharp laser-like pang that reverbs across the lake seems like a mixture between being in a mysterious underwater world with distant whale calls and being stuck on a Star Wars battlefield with blasters firing lasers all around you. Hearing the singing ice of a frozen lake in person is truly a sound to behold.

The explanation for these mystical noises comes down to the ice itself. The odd noises are not from the ice cracking, but rather the sound vibrations moving through the ice so that the force of a crack, or pressure from excess ice formation, can dissipate and not build up. We think of ice as a solid unmoving structure, but the ice on a lake is constantly shrinking and growing. The intensity of the sun can start to melt lake ice and it will shrink towards the center of the lake.

The ring of exposed water around the outside will start to re-freeze due to the cold air. Once the sun’s power wanes the shrunken ice in the middle will start to regrow and collide with the newly formed ice along the edge. The force that happens when the ice pieces push against each other dissipates as vibrations of sound through the frozen chunks giving it an eerie, almost laser-like effect. Other noises are produced by the cracking of ice at its weak points as it expands and contracts producing lower toned notes.

Whether you are looking for the silence of a fresh snowfall, or an unconventional song performed by frozen lakes, the winter season in Minnesota has you covered. As we mourn the loss of warmer weather and sunlight, know that there are still some experiences that make winter beloved in its own way.   

December Events at the Hormel Nature Center

Thursday: Merry & Bright Night, 4-7 p.m. Free and open house with Santa.

Dec. 18: Red Cross Blood Drive, Noon to 6 p.m.

Dec. 24-25: Interpretive Center Closed