In this video, shot just a few days after the start of the new year, large ice boulders are seen clanking against one another along the shores of Lake Michigan. What are they? Where did they come from? Can we use them to make massive cocktails?
If I were Calvin's dad — as in "Calvin and Hobbes" — I would explain in great detail how an ice boulder company based out of Muskegon lost one of its capital steamer transport ships in a recent gale. Every man on board was lost and the entire year's shipment of ice boulders for the small village of Frankfort was lost to the lake's icy waters.
But since I'm not Calvin's dad, I'll share the real explanation for this fascinating natural phenomenon. The ice boulders are not unlike pearls, which are formed by oysters when a "seed" — usually a piece of sand or broken bit of shell — is trapped inside the oyster and is irritating enough to be covered in a thin coating of "pearl juice" as a defense mechanism. The "pearl juice" hardens around the irritating seed. Do this many, many times and you get some big pearls.
Or in this case, ice boulders. These ice boulders are made in the same way — except that instead of being formed inside an oyster, they are birthed in the waters of Lake Michigan. They start out life as a small chunk of ice in the water. Like the oyster's sandy seed, the small chunk of ice grows by thin measures as it tumbles in the waves. Ice boulders can only form when the air is cold enough for the water to instantly freeze and the lake is cold, but not too cold. A stiff breeze helps to churn things up. When a face of the ice boulder is hit with the water from a wave, it freezes in the cold air, getting just a bit larger in size.
After hours of tumbling, what started out as a small chunk of ice can grow to the behemoths you see in the videos above and below. It doesn't happen often, so when it does, it's something to celebrate and take note of.
Here are a few more videos showing the ice balls in action.
Nature is awesome!