Abstract bubble-like patterns reveal where pockets of air got under the pond ice. At left, a leaf tip breaks the ice, allowing air to fill the space when the water level dropped slightly. Bob King / firstname.lastname@example.org
By Bob King, Duluth News Tribune
I love ice. Molded by cold and wind, it takes on the most whimsical shapes and patterns. On a recent hike, I walked to a frozen beaver pond and spotted one of those “dark stars” in the ice. It opened my eyes to others and before long, I was a little kid with a magnifying glass.
Hundreds of medium-sized bubbles and thousands of tiny ones riddle a layer of ice over a natural hole in the pond. Bob King / email@example.com
While beautiful in their own right, each pattern crystallizes for a reason. Puzzling out the “how” of what I saw was just as enjoyable as the sight.
What looks like a giant neuron is sometimes called a “star” or “slush fingering.” It can happen when a pond or lake develops a thin layer of ice followed by a snowfall. The weight of the snow pushes down on the ice, slowly forcing water up through small holes. The water enlarges the holes and spreads into a spidery pattern. When the snow becomes slush and then freezes to ice, the “star” is frozen into place. Bob King / firstname.lastname@example.org
Beguiled by ice, I didn’t leave the pond until almost sunset. On the walk back I lost the path in the deep twilight of a cedar swamp and had to circle back. I found my way again and finally got out of the woods at nightfall.
Graceful curves in grasses along the pond’s edge are frozen into place. Bob King / email@example.com