Ah, it’s January, a time when sweet summer children who grew up in warm climates (or at least who spent most of their winters indoors) suddenly discover that ice on frozen lakes and ponds can make freaky noises.
Those of us who grew up in snowy places have known about this acoustical phenomenon for years, but that hasn’t stopped the internet from “discovering” it with some regularity. Back in 2014, YouTuber Cory Williams mesmerized 11 million viewers with the “coolest sound ever” when he tried skipping rocks across a frozen Alaskan lake. And today, a similar video is going viral, featuring Australian YouTuber Kyle Kennedy sliding a sheet of ice across a frozen pond in the U.K.
The resulting sound is pretty cool, and naturally, there’s an excellent scientific explanation for it.
As acoustics expert and University of Texas, Austin, professor Mark Hamilton explained to Livescience, the sheet of ice atop a frozen lake or pond acts as a vibrating plate, so the impact of a rock or ice sends a bending wave through the ice that radiates sound into the air. The shorter, higher-pitched sound waves hit your ears first (if you’re standing far enough away to hear the difference) followed by lower-frequency waves, creating eerie and unusual sound effects for the listener.
While examples of frozen pond and lake noise will inevitably keep popping up on YouTube, it’s not too late to trek somewhere cold and experiment with the phenomenon yourself this winter. Just be sure to keep your feet on dry land while you’re discovering the wonders of nature.