Ice tsunami

via ---> CNN

The ice moves inexorably ashore, crackling as it goes like thousands of windows breaking. In minutes, it's moved from the shoreline of a Minnesota lake to the walls of homes along the lake. "It was just pushing and breaking and pushing and breaking," Darla Johnson, who made a video of Saturday's "ice tsunami" on Mille Lacs Lake, told CNN affiliate WCCO-TV in Minneapolis. Johnson's video had more than 275,000 views on YouTube by Monday morning. And once you watch it, you can't stop. It's like a sci-fi movie, and there's certainly science involved. Christopher Tetrault, a conservation officer for the area with the Minnesota Department of Natural Resources, said the weather event works like this: Strong winds blow heavy chunks of ice out in the lake toward the shore. Those chunks heave up bits of lighter, melting ice closer to shore up on the land. The more the wind blows, the more ice comes onto land.



"It basically has the same mechanism of an iceberg," said Todd Borek, a CNN meteorologist. "Winds, but more so ocean currents, allow icebergs to drift. Same premise: A chunk of ice (relatively shallow) was pushed by a strong, sustained wind. The momentum of the ice sheet overcame the friction of the landTetrault said the ice came about 60 feet to 80 feet inland Saturday, getting as high as 30 feet in some places. The ice mass covered up about 2.5 miles of shoreline, he said. At least one home had 2 to 3 feet of ice spill through its patio glass doors, and some boathouses along the lake were destroyed, he said. It was something Tetrault, who's only been stationed on Mille Lacs Lake for a few months, hadn't seen before.

But longtime locals told him they couldn't remember anything similar since the 1950s. The same phenomenon was seen Friday on Dauphin Lake in Manitoba, about 75 miles northwest of Winnipeg, where a wall of ice up to 30 feet high destroyed six homes and damaged 14 others, according to a report from the Canadian Broadcasting Corp. "This is worse than a flood, because with a flood, the water just goes through and it's finished. With this, there's still so much ice out on the lake that if the wind picks up again, it could start all over,"


"You know you've got cement, concrete blocks and steel, and the ice goes through it like it's just a toothpick," Dennis Stykalo, who also lost a home to the ice, told the CBC.

 "It just shows the power. There is nothing you can do; you just get out of the way and just watch."

 In Minnesota on Monday, people were watching the ice there melt, a steady rain helping the process, Tetrault said. Temperatures on Tuesday expected to be in the 80s or higher were also expected to help, both with the ice onshore and the larger sheet now 200 to 300 yards out into the lake, he said. Still, that ice mass was about 16 inches thick Monday, and the weather can change quickly in Minnesota.

"It's not as significant as it was," Tetrault said, "but you never know with what Mother Nature does."

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