Thousands of huge snowballs recently appeared along 11 miles of coastline, surprising residents of Nyda, Siberia. Locals say they’ve never seen a phenomenon like this one, and they documented the phenomenon in social media posts. Some of the snowballs are as small as a few inches, while others are nearly three-feet-wide.

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The icy orbs started showing up around two weeks ago near the small Siberian village north of the Arctic Circle. While the snowball-swathed beaches may look like preparations for a giant snowball fight, natural processes actually led to the strange balls.

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The snowballs apparently form when water and wind roll ice pieces. Valery Akulov of the village administration told The Siberian Times, “When the water in the gulf rose, it came into contact with the frost. The beach began to be covered in ice. Then the water began to slowly retreat, and the ice remained. Its pieces were rolling over in the wet sand, and turned into these balls.”

Arctic and Antarctic Research Institute spokesperson Sergei Lisenkov told The Siberian Times, “It is a rare natural phenomenon. As a rule, grease ice forms first, slush. And then a combination of the action of the wind, the outlines of the coastline, and the temperature, may lead to the formation of such balls.”

Akulov said village “old-timers” had never seen such a phenomenon before, and locals expressed disbelief and amazement at the snowballs. Local Ekaterina Chernykh said, “We all were very surprised. Many people believed it only when they saw with their own eyes. This has not happened previously. And there was not so much snow for them to form. It’s so interesting.”

Locals compare the size of smaller snowballs to tennis balls and large ones to volleyballs.

Via The Siberian Times, the BBC and Gizmodo

Images via screenshot