Jan. 30, 2010.
Nick Lapointe on lake ice
Rob led us through the woods and out onto White Lake’s Pickerel Bay. We made our lunch fires on the ice along a sunny shore, out of a stiff west wind, while Nic Lapointe sought out deeper water for some ice-fishing. He had brought a six-inch auger and soon hauled a Perch up through the hole. Gabriel, who seems impervious to cold, stuck his arm down the hole to feel the bottom of the 18-inch-thick ice. Solid though it obviously was, the ice made deep booming sounds as it contracted.
A few of us put on skates and threaded our way through the maze of icy patches among the lines of drifted snow out on the lake. We tried drilling new holes with Nic’s auger, but mainly slid round and round in the opposite direction.
Feb. 20, 2010.
Dendritic pattern of water flowing over and down through lake ice
This is a feature frozen in lake ice. What is it? That’s what Rob asked the assembled Macoun members at this day’s meeting. Then, with lots of pictures, he showed them that this was an unusual, lopsided form of a natural ice phenomenon that he calls “ice stars.”
After studying them in a mild winter when they were common, he determined that they are essentially drainage channels for water, converging on a hole down through the ice. Ice floats with its top surface a little above lake level, and if rain or meltwater has soaked into the snow, that water will flow out of the slush and down through any weak spot in the ice. This happens slowly, over a period of hours. Holes may open up around sticks or rocks, where methane bubbles accumulate, or over submerged logs and boulders.
At first the water moves in a sheet through the layer of slush, but eventually sorts itself into narrow drainage channels, which can reach out five feet in four or five directions and have short branches, or tributaries. The ice star pictured here, only three feet long, is lopsided because the ice was close to shore and its surface was tilted.
One of Rob’s pictures showed that the drainage channels actually curve down the hole and along the underside of the ice. This led to a discussion of how Bombardier beetles direct their vile spray, what went wrong with the world’s first attempted jet-engine-powered flight in 1910, and the Coanda effect (named for the pilot of that ill-fated flight), which ties all of these things together.
The older members stayed on afterward for their own special meeting, at which, as a treat, Rob served up a deep-dish apple pie he’d just baked.
Feb. 27, 2010.
Snowshoer in despair
We faced challenging conditions as we set off into the Study Area woods again, where the snow was both deep and wet. Winter boots and gaiters worked best. We found seven Porcupines, all up in trees, and recorded their locations by GPS. We also waypointed several Butternut trees.
Prohibited from making snowballs (because of the inevitable snowball-in-the-leader’s-face), the Macouners became increasingly creative in their requests: “Is it all right to make a sculpture? OK, here’s one of a tennis ball.” How about a frisbee? Rob said he’d be OK with a snow boomerang, and Gabriel really tried to make one.