Ice of another kind…
Louise Hatfield was out for a walk when this tower of ice caught her eye. Here's the science behind the spike:
Published Thursday, January 26, 2017 11:51AM AST
Last Updated Thursday, January 26, 2017 12:27PM AST
We’ve been talking about ice for a few days now. The storm that tracked across our region with wind and rain, brought more than 12 hours of freezing rain to many parts of New Brunswick and northern mainland Nova Scotia. Today’s milder temperature will help, but it’s going to be a while before things return to normal in the hardest hit areas.
Now, not all ice falls from the sky. Last week, I received an email from Louise Hatfield, from Pubnico Head, NS. She attached the above photo and was wondering what it was.
Louise came across an ice spike. Ice spikes occur naturally, and they usually take on a triangular shape; I’ll explain why in a moment. They tend to form in containers; perhaps you’ve seen them in a bird bath or your pet’s drinking bowl. They are more likely to form in smaller spaces but they form on larger bodies of water.
Water expands by 9% as it freezes into ice and the simplest shape of an ice crystal that reflects its internal structure is a hexagonal prism. That’s why they often, especially in smaller spaces, end up looking like a triangle.
Ice spikes grow as the water turns to ice. The ice slowly freezes in from the edges, until a small hole is left unfrozen in the surface. Since ice expands as it freezes, the ice freezing below the surface starts to push water up through the hole in the surface ice. If the conditions are just right, the water will be forced out of the hole in the ice and it will freeze into an ice spike, not unlike lava pouring out of a hole in the ground to makes a volcano. With time, as water continues to come up through the hole, it freezes around the bottom and the spike continues to get longer or taller.
We can learn so much by looking around; another marvel from Mother Nature!