Last night lots of ice blew up on the shore across the street from the school. We know it was blowing at least 55 mph (about 88 kph) because the bridge was closed to high-profile traffic for about an hour last night.
It may have been right across the street, but we had to take a "field trip" to check out the blue ice the kids had heard about on the news.
I did some research, because you know, I'm nerdy; I wondered why the
ice is blue some years but not others. Apparently the ice isn't really
blue - it just appears blue. It's all about how much light can penetrate
the ice. On years like this one, when the ice freezes slowly there are
fewer air bubbles and larger ice crystals. That combination allows light to
penetrate deeper into the ice. Six times more red light is absorbed by
the ice than blue light (remember, white light is made up of all the
colors of the visible spectrum.) Since that red light isn't reflected
back to our eyes, the ice looks blue.
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