Is it just me, or is this an unusual spot for an icicle to form? Just one huge “dagger” of an icicle hanging from these power lines in Belleville? I’ve certainly seen ice on power lines before, but usually it looks like this or like any of these. If you look at the power lines in my photos below, they seem to be clear of ice other than in the one spot here where it formed. And I don’t know about you, but if I owned the car below left, I don’t think I’d leave it underneath this icicle – that’s a pretty heavy ice dagger that will eventually drop!
In trying to understand how this one icicle could form, I did a little research. Perhaps there was originally snow sitting on these wires, and when the sun melted the snow, the water flowed down the slope of the wire and began to drip at this one point. The water dripping eventually encountered cold air and formed a pendent drop suspended from the wire. The air is below freezing, so the suspended drip starts to freeze. For an icicle to form and grow, there must be a constant layer of water flowing over it, forming a thin fluid layer of water around the icicle.
But if the water was flowing (in small drops?) along these very narrow power lines, what might make it stop and freeze in this one central spot? The lines look like they were relatively tight and not sagging until the weight of this icicle was formed. And why do none of the other wires in these pictures have ice?
Just in case you have any interest in reading further about how ice forms on power lines, here’s an article that goes into the differences of ice on transmission lines vs. ice on distribution lines and the concepts of “galloping” lines. It says “transmission lines are designed to handle 1 1/4 inches of ice,” with no mention of how this is handling 40 inches of ice!