Bizarre sand sculptures rising from the beach at Lake Michigan caught the attention of at least two photographers in early January, who posted their photos of the natural wonders online.
But what are these sand sculptures and how on earth did they come about?
Their construction depends on several factors, including sand-to-water content and wind conditions, said Daniel Bonn, a physicist and head of the van der Waals-Zeeman Institute at the University of Amsterdam.
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The pillars, also known as hoodoos, were of varying heights, anywhere from 3 to 20 inches (7.6 to 51 centimeters), said Terri Abbott, a wildlife photographer living in northern Indiana. Abbott was visiting Tiscornia Park in St. Joseph, Michigan, on Jan. 8, when she noticed the beautiful shapes on the snowy beach.
“Laying on the ground and shooting through these sculptures made it seem like a different planet,” Abbott told Live Science in a Facebook post. “They were frozen and hard to the touch. The intricate and ever so sharp edges made them each amazing in their own way.”
Abbott had never seen such sculptures. “I couldn’t believe how perfectly chiseled they were,” she added.
Michigan is freezing winter temperatures helped pave the way for the formation of the strange, chess-like pieces, according to Bonn, who was the senior researcher on “How to Build the Perfect Sandcastle,” a study published in the journal Scientific Reports in 2012.
“I roughly think there are liquid patches in the sand that freeze when it gets cold,” Bonn told Live Science in an email. The coast is a windy place, he noted. When the sand-laden wind blows into these frozen patches, two seemingly opposite actions happen: In one, some grains of sand can cling to the frozen patch, causing it to grow, he said. “This then forms a roughly cylindrical consolidated sandcastle-like structure,” Bonn said.
In another, the wind and sand it carries can erode the sand pillars and take sand away, “leading to the rings and the asymmetrical shape of the cylinder,” Bonn said.
Some of the sand eroded by these pillars ends up elsewhere on the beach. In some of the photos, “you can see there are point-like structures downwind that result from the sandblasting of the cylinder,” he said.
Joshua Nowicki, a photographer from southwest Michigan, stumbled upon the same sand pillars in Tiscornia Park on Jan. 7 and 8. Nowicki, who has seen similar sand structures before, noted that these pillars, while rare, come at any time of the year, “when there is wet sand and sustained high winds for several days.” In most cases, “they only get bigger than a few inches in length when the sand is frozen over (from rain, melted snow, spray from crashing waves),” Nowicki told Live Science in an email.
The sand sculptures he saw this year “are some of the tallest I’ve ever photographed, the largest is about 15 inches [38 cm] long and a few inches in diameter,’ Nowicki noted. “Along the beach there were at least six groups with thirty or more sand structures in a group and one group had quite a few more.”
Most pillars do not last long. Usually, within a few days, “the wind completely erodes them or knocks them down; when temperatures rise above freezing, they crumble; and often in winter they are quickly covered by drifting snow,” Nowicki said.
The pillars of Tiscornia Park crumbled earlier this week as temperatures began to rise, Nowicki said. “The fact that they have only been around for a short time makes them very special,” he said. “You have to be there at just the right time to see them when the shape is still well defined.”
Originally published on Live Science.