Needed really smart person

[mavdog]

So Im taking this class on Ice Rescue and we go over ice formation and the different types of ice. We get into water density and thermoclines and how water at 39.2F is at its highest density and above or below that temperature water rises.

I ask the Instuctor what about moving water? Can one expect to find water in its liquid state below its freezing point of 32f? I understand that you can increase the salinity or add some other type of pollutant and decrease the freezing point.

I also understand and have read reports on super cooled water both at altitude and in the lab where the crystallization can't begin without some type of condinsation nuclei.

My question is this: How cold could moving water such as a river or mountain stream get and still flow in any given place on the earth?

 

[Walter]

Glaciers flow, they just flow very slowly.

 

[gary-ramey]

Here's one that will blow your mind. Glass is a liquid. Also, did you know that water is one of only two liquids that becomes less dense when it freezes. If not, those rivers and lakes would freeze from the bottom up destroying all life in the process.

 

[mavdog]

Here is what I found so far for anybody that cares the condensed version.

In moving water the Ice crystalizes in whats called a honeycomb frazile structure which means the ice crystals are concaved and able to hold liquid which act as an insultator for that crystal, added to the latent heat of fusion and polution this liquid can drop below 0c/32f and stay in its liquid state. It seems also that this supercooled liquid is less dense than the ice and will continue to rise to the surface.

How cold this will/could get in nature appears to have too many variables to calculate. But, if it gets to far below 30f the fish will freeze and die.

If you know anymore or that something here is wrong please correct me as most of my information came from the internet.