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Water at the top of the pond is exposed to the cold air before the bottom is and that wonderful property of ice to float keeps it there.
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I don't think that's entirely correct. I think MageB420666 was on the right track and that it has to do with pressure. The water below the surface is under more pressure. Pressure reduces water's freezing point, thus the water at the bottom may actually be colder than the water at the top but not freeze due to pressure.
http://www.lsbu.ac.uk/water/explan2.html#Pvisc
Interestingly enough, the minimum temperature that liquid water can exist without ever freezing is -21.985°C at 209.9 MPa.
The shit they didn't teach me in high school astounds me.
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You know something, I don't think the sun even... exists... in this place. 'Cause I've been up for hours, and hours, and hours, and the night never ends here.
Last edited by Master_Shake; 02-08-2005 at 07:59 AM..
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