A rare collection of “ice eggs” has been spotted in Finland, a phenomenon experts say only occurs in highly particular conditions.
Photographer Risto Mattila said he and his wife saw the icy balls spanning a 30-meter (98-foot) stretch of sand on Sunday while strolling along Marjaniemi beach on Hailuoto island.
“The biggest of the eggs was about the size of a football,” said Mattila, an amateur photographer. “It was an amazing view. I have never seen this phenomenon before.”
The phenomenon is rare, but under ideal weather conditions, it might occur once a year, according to Jouni Vainio, an ice specialist at the Finnish Meteorological Institute.
“You need the right air temperature (below zero, but only a bit), the right water temperature (near freezing point), a shallow and gently sloping sandy beach and calm waves, maybe a light swell,” he said.
“You also need something that acts as the core. The surf pushes the ice ahead and backward along the beach while the core starts to gather ice around it. The surface of a tiny ball gets wet, freezes, and grows larger and larger.”
Autumn is the perfect time to see the phenomenon, according to Dr James Carter, emeritus professor of geography-geology at Illinois State University, as this is when ice starts to form on the surface of water, creating a form of slush when moved by waves.
He remarked, “I can visualize the surface moving back and forth to shape the slushy mix.” “The world can now see something that most of us would never be able to see because of the photographer who shared the images and observations.”
