eli5: Why did the ice clear my pond?


My pond was quite murky, then one day it froze over and the water is now crystal clear why?

In: Earth Science

The formation of the molecular activity? Once the water particles stop moving enough for the light to pass, you can through the ice. Who knows?

Water is still cristal clear after it unfroze?

Most likely the ice on top slowed the turbulent action of any wind, allowing the suspended matter to settle out.

Clear ice forms in very specific circumstances. The day and night must be calm, the day time temperature must hover just above freezing, the night time temperatures must plunge below freezing quickly. This forces all the particles in the water down towards the pond bed and forms a smooth surface above that is crystal clear

When you say “murky” what do you mean?

If the water was brownish, that’s suspended mud sediments. In that case, as mentioned elsewhere in the thread, the ice might have prevented wind from stirring the water and stirring up the mud.

If the water was a pea green, then that’s suspended single-celled algae. Freezing over the pond killed the algae…either the temperature got too low or the ice cut off light from the pond (especially if snow fell on the ice).

If the water was covered by hairlike green algae and other miscellaneous scum, that’s drifting multicellular algae (and possibly some plants like duckweed). Freezing killed them off, they sank to the bottom, and now you can see into the pond.