Mysterious 'Pancake Ice' on River in Scotland

These strange lily-pad formations occur when conditions are just right. Sunday, 5 November 2017

By Brian Clark Howard

Strange-looking formations that resemble frozen lily pads appear from time to time on Scotland's River Dee. Called "ice pancakes" or "pancake ice," the natural formations occur when conditions are just right.

The ice disks form when waves jostle pieces of smooth ice against each other, rounding their edges. As the resulting pancakes collide with the waves, they develop raised edges, making them look even more like lily pads.

Jamie Urquhart, a biologist with the River Dee Trust, spotted ice pancakes at Lummels Pool, a few miles downstream of Queen Elizabeth's summer residence at Balmoral.

What makes his pictures surprising is that pancake ice is most common in cold oceans, so it's frequently seen around Antarctica and in the Baltic Sea.

But it can form anywhere that conditions are right, including on the Great Lakes of the United States.

It’s also "especially unusual to see pancake ice frozen so hard that someone could pick it up," as some of Urquhart’s pictures show, says Ted Scambos, a lead scientist at the National Snow and Ice Data Centre in Boulder, Colorado.

"Usually pancake ice is more like a slush."

As to media reports suggesting that the River Dee ice formed from frozen foam, Scambos says it is possible, although the ice would have developed into pancake shapes in the same way, through jostling.

Ice pancakes often eventually meld together to form sheet ice. If the ice gets thick enough, and the water is rough enough, the ice can bend, fracture, and pile up on itself, forming what are called ice ridges.

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