The strange 'sand board' appeared along the American lake

Water, sand, wind, and low temperatures create naturally shaped columns of sand on the shores of Lake Michigan.

Strange "sand sculptures" appeared on the shores of Lake Michigan, USA, in early January, attracting the attention of photographers. Their formation depends on many factors, including sand, water and wind conditions, says physicist Daniel Bonn, head of the Van der Waals-Zeeman Institute at the University of Amsterdam.

Picture 1 of The strange 'sand board' appeared along the American lake
Sand columns "decorate" the shores of Lake Michigan in Tiscornia Park, behind is the North Pier lighthouse.

The sand pillars, also known as hoodoo, vary in height from 7.6 cm to 51 cm, said photographer Terri Abbott. She saw these strange natural structures on the snowy sands while visiting Tiscornia Park in St. Joseph, Michigan, on January 8.

Michigan's frigid winter temperatures have allowed the chess-like structures to form, according to Bonn. "I assume there are liquid parts in the sand that freeze when it's cold," he explains. The sands of Lake Michigan are windy. When sandy winds blow against these frozen bodies of water, two seemingly opposing things happen.

First, some grains of sand can cling to the iceberg, causing it to increase in size. This creates an almost cylindrical sandcastle-like structure. Second, sand-laden winds can erode the sand column, removing the sand and causing the cylinder to take on an asymmetrical shape. Some sand grains pushed out from these columns will be swept to another place by the lake.

Photographer Joshua Nowicki also caught the sand column at Tiscornia Park on January 7 and 8. He has seen similar structures before and said they are rare but can appear at any time of the year provided there is wet sand and strong winds lasting a few days. In most cases, they are only a few centimeters tall, Nowicki said.

The "sand sculptures" Nowicki saw this year are among the tallest he has ever photographed, the largest of which is about 38 centimeters high and several centimeters in diameter. "Along the lakeshore, there are at least six clusters with 30 or more sand columns in each," he said.

Most sand columns do not last long. Usually, within a few days the wind will completely erode or topple them, says Nowicki. If the temperature rises above freezing, they will also crumble. In addition, in winter, they will soon be covered with snow.

The sand poles at Tiscornia Park collapsed earlier this week as it started to warm, Nowicki said. "The short lifespan makes them very special. You have to be there in time to see them while the shape is still clear," he said.