Life is mathematics. Add to your income. Subtract from your weight. Divide your time. Avoid multiplying... we should all have been paying more attention back in high school. Not just to math, but to physics.
If you skipped those classes, however, there's a physics lesson underway right now out on the Lake of Bays. The ice out there is now about a foot and a half thick. With the cold nights, the lake continues to freeze. As we get into March, on cold nights, we'll hear the ice begin to "boom", a shuddering electronic noise that comes with expanding ice and non-expanding shores.
As water freezes, it expands. This in turn causes the ice to push against the shore of the lake. Said shore is granite. Pre-Cambrian Canadian Shield granite in fact. It's been where it is for millenia, and it's not going anywhere anytime soon.
The ice shoves on the shore -- an irresistable force. The shore just stays right there -- an immoveable object. Something's gotta give...
And it does. A pressure crack will run through the ice, taking off the strain, and shifting the ice (sort of like miniature tectonic plates deep in the earth). The ice will either buckle upward, buckle downward, or slide over itself. These can be risky if you hit them with a snowmobile, so it really matters that you not only know the lakes you are riding on, but you know where the pressure ridges are, or might be, and ride with caution. These ridges can form surprisingly fast.
Brian took a picture of this ridge just south of Bigwin Island this week.
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