5184 x 3456 px | 43,9 x 29,3 cm | 17,3 x 11,5 inches | 300dpi
Data acquisizione:
11 febbraio 2012
Altre informazioni:
I liked to stomp on hollowed-out frozen puddles to hear their crunch. Sure, I sometimes wondered, as many kids probably do, about what happened to all the water and why it happened only to some of the puddles. But such puzzles don't linger in the mind of a kid for long. When a film of water on a smooth surface like glass or a car roof freezes, the preferred crystal orientation is that with the arrow pointing straight up and out of the surface. So, I find the above pattern mysterious - why don't the arrows have any trend toward pointing upward? Why do all the arrows stay in the same plane? Another mystery is the fact that I’ve seen this same whirlpool pattern with about the same center spot on both side mirrors on more than one morning. Perhaps the whirlpool pattern arises somehow because the surface is curved. Or maybe films of water on plastic freeze differently than films on smooth metal or glass. For now, I’ll call this the mystery of whirlpool hollows. Foam floating about on the water, which you can see in the video, started to freeze, probably at night. Bits of frozen foam got pushed around in the eddy, and in the ensuing collisions, became roughly circular. Perhaps each disc grew radially when smaller pieces of unfrozen foam struck the disc, adhered and spread out a bit along the perimeter, and then froze in place. Visiting some large puddles along the trail, Emerson marveled at the smooth, glass-like surface of the frozen puddles. Some of them held in them unique and wondrous designs. Emerson walked upon a shallow puddle as I cautioned that the ice may not be thick enough to hold his weight. It started to crack and the water surged up and around his boots. While he found this curious, he also seemed to understand and moved slowly out of the puddle. I pointed out that if the ice is not thick enough, it will break and you will fall through it. Simply put - ice can be dangerous but if you want to play with it, get an adult to make sure it is safe.
