This Rare Blue Ice—Normally Found In Glaciers—Is Piling Up In Michigan

Tourists are flocking to see this rare sight—and do you know what causes it to appear blue?

Folks in northern Michigan are getting to enjoy a phenomenon normally only seen in glaciers: blue ice, piled up in the Straits of Mackinac.

Photographer Kim Mettler has lived in the area for about two years and had never seen blue ice there before. She drove about an hour on Tuesday to take pictures near the Mackinac Bridge.

Kim Mettler/Instagram

“We had a warm-up here in Northern Michigan, which is why I went out that day,” she said. “It was about 40 degrees with partly cloudy skies.”

Kim Mettler/Instagram

She saw a lot of people clamber dangerously far into the frozen straits, which separate Lake Michigan and Lake Huron, to explore.

The ice isn’t really blue. It gets its otherworldly glow because it doesn’t have bubbles in it, so it easily reflects the blue part of white light.

Kim Mettler/Instagram

A wind storm over the weekend piled up chunks of ice on the shore in Mackinaw City.

Kim Mettler/Instagram

Resident Rick Caldwell told the Detroit Free Press that locals haven’t seen blue ice like this in seven years. Caldwell works as a front desk manager at a local hotel, and he said the “tourism has been crazy.” He said the hotel chain he works for, Hampton Inn, even had to open other hotels nearby—that were presumably closed for the ordinarily slow winter season—to accommodate the influx.

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Written by David Williams for CNN.

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