Re: Need Beginner Equipment Help

Chris Guynn wrote:
"John Hanson" wrote:
Google it. He made that comment before.

Perhaps you could point it out. I looked in google groups and didn't find
find it.

I couldn't find it either.

The closest thing I could find to this topic (depth of ice) was when he said
"And "coldest" means "lake ice will be the thickest". " Tell me that you
aren't using that statement to justify your prior claim.

It might have been something misinterpreted from a few weeks ago, when
John claimed something like experiencing a 35F bottom temperature,
which unfortunately violates the laws of buoyancy, since water is most
dense at 4C (39-40F)...and in short, is why ice floats, and lakes
freeze from the top down.

More on that can be read here:

<http://en.wikipedia.org/wiki/Water_(molecule)#Density_of_water_and_ice>


I recall that there was a conversation in which I mentioned that
there's some MN lakes that don't support fish life, a fact that isn't
contested. I had been told that this phenomenon was because the lakes
"froze solid", but apparently, the more common mechanism is that the
lake merely freezes enough to become a closed system and when these are
too small, the fish suffocate after they deplete the available O2 in
the remaining liquid water under the ice plug. In any event, how thick
the ice gets on a lake is merely a function of the environment. For
example, Antarctica's Lake Vida has frozen 60+ft thick, and clearly
would have frozen solid had it not been endorheic, given that its
current water brine temperature under the ice is -10C (14F).


-hh

.

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