Ice Pattern

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Ice Patterns on Binnewater Lake.

These attention-getting patterns in lake ice were observed over Binnewater Lake, New York on January 24, 2020. This photo was taken from a small (2 seat) plane. The ice was in the process of melting. Trying to explain all of the odd ice patterns seen on lakes and ponds, even on puddles, is challenging since so many factors play a role, many that aren't at all obvious at first glance.

In most years, lake ice doesn't freeze evenly so it regularly contracts and expands throughout the season. Initially, a hard freeze perhaps caused the ice to contract, forming the cracks. The circular ring pattern shows that the primary source of the stress was radial. A small upflow hole in the ice is where the ring pattern originated. As the ice began to melt, open water rose through the cracks and after another freeze this water froze and expanded. This process was repeated with additional thaws and freezes. Presumably, the ice further from shore was thinner, so more readily cracked. Note also the pond stars close to shore.

Photo Details: Camera: LEICA SL2; Software: Adobe Photoshop CC 2019 (Macintosh); Exposure Time: -1717986s (1/0); Aperture: ƒ/4.0; ISO equivalent: 400; Focal Length (35mm): 280.

Binnewater Lake, New York Coordinates: 41.8978, -74.0583

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