THE WASHINGTON POST – Around the Great Lakes of North America, the winter season brings cold winds, frigid water and a chance to see stunning formations called ice volcanoes. While they look like real volcanoes, ice volcanoes aren’t hot. Instead these naturally occurring structures exist only in extremely cold temperatures.
Ice volcanoes, sometimes called “ice canos,” are short-lived occurrences, because there must be certain weather conditions for them to happen.
“What you need is prolonged periods of really cold temperatures,” at least below freezing, said Tom Finley, director of education at Schlitz Audubon Nature Center in Milwaukee, Wis. In other words, “whatever you would think are the worst conditions to be outside in” are the best conditions for ice volcanoes.
During winter, strong waves and winds cause ice to form on the shores of Lake Michigan, creating structures called ice shelves. If the weather remains cold enough, the ice shelves enlarge and extend over the water, with liquid still flowing beneath them. That’s when ice volcanoes can begin to take shape.
“This water flowing underneath will start to erode the bottom side of the ice shelf,” said Finley. Cracks form, and eventually the rushing water “might pop a hole through to the top of the ice.” After water escapes through the opening, it freezes immediately, forming a small mound that resembles a volcano.
As the ice volcanoes grow, the beach begins to look “like a completely foreign landscape,” Finley said. The beautiful, strange formations remind him of pictures of the moon or Antarctica. To see them up close feels “like you have been transported to another planet.”
You can determine whether an ice volcano is young or old by its size. New ice volcanoes are tiny, but older ones can be huge – even taller than a person. Climate change affects how often ice volcanoes form and how long they last. As the Earth gets warmer, we’re experiencing milder winters – and ice volcanoes are becoming more rare.
“Depending on the severity of the winter, you can have a lot of ice canos or a few,” Finley said. January 2020 was the Earth’s hottest January on record, according to the National Oceanic and Atmospheric Administration. Although ice volcanoes formed along the Great Lakes last year, they didn’t stay long, Finley said.