Any Tips On Keeping Water From Freezing On Climbs?

[mike1]

pack the bottle upside down so the bottom freezes rather than the top?

A friend showed me this trick once.

Question: Why does the water on top freeze first? I've set a nalgene upside down on the glacier next to my bivy to test it and sure as sh*t only the bottom of the bottle froze, not the portion contacting the glacier... Maybe the outside air temp. was lower than the glacier. if so then a suspended bottle (or equally insulated) would freeze evenly? Sooo, IF that's correct then it only works when you leave your water on the ground? Or is there some thermodynamic molecular reaction taking place?

[Dru]

it freezes from the air down.....if your bottle had no air bubble it wouldnt matter which way it was pointed.

[mike1]

Why?

[Dru]

cause air gets colder faster than water does.duh! why does a lake freeze on the surface first - same thing!

[mattp]

Its been a while since I sat in a science class, Dru, but I recall something about how water is unique among liquids in that the frozen stuff floats on top rather than sinking to the bottom -- it is a question of density, I think, rather than the direction of heat loss. Ice is lighter than water, so it floats on top.

[Dru]

you can't cool liquid water past zero C but you can cool air to -40C (for instance). the cold air freezes the water at the interface.

 

sure if ice sank the lake or water bottle would freeze bottom up - but it doesnt

 

Ok Matt? You are interfering in a perfectly good session of "trollin' for CBS with chemistry doubletalk". I'm going to have to throw you back.

[iain]

Without a condensation nucleus, water can remain liquid well below 0°C

 

How on earth do you think people would climb Mt. Hood w/o the rime ice?

[Dru]

Actually that would be a "freezing nucleus". Condensation is an inappropriate term for the liquid to solid transition. You will have to "de-thaw" your chemistry knowledge some more

[iain]

I thought "freezing nucleus" was more appropriate with something immersed within a body of water, rather than the rime ice example, where an object provides a catalyst for the process of supercooled water vapor condensing and subsequently freezing on an object. Oh well, it wasn't a good analogy I gave anyway. I guess riming structures would be a "deposition nucleus" or something like that.

[Dru]

The catalyst for the supercooled droplet freezing is the surface it strikes at high speed.

[mike1]

Hey, isn't this a climbing forum? he he he, I love it....

so you're saying if I floated a water ice cube into space it would remain 0 degrees even though a thermometer would read something near kelvin? what about temperature gradients? Dru, I'm just yankin yur chain man... But since I got everyone talking physics here's another question; Why does water boil at lower temperatures at higher altitudes? And don't give me some bs like, "Duh, it's air pressure".

[Dru]

liquid water does not equal water ice cube there einstein

[catbirdseat]

Okay, I'll bite. It is true that air cools faster than water, because of its lower heat capacity. However for the air comprising the headspace to cool, it must first lose it's heat through the bottle and this is also true of the water below. I just think the reason it freezes first at the top is that the water/air interface and film on the inside of the cap, provides a better place for ice nucleation than the body of the water below. We are not talking about ice forming below and floating up because that isn't what happens.

[Bogen]

I thought it had something to do with crystalization occuring at the surface, where the molecules are already somewhat aligned.

[mattp]

We are not talking about ice forming below and floating up because that isn't what happens.

 

I didn't mean to imply movement of that sort, Brian. Am I correct in remembering hearing that most liquids, when they freeze, form solid from the bottom up -- unlike water?

 

It seems other people remember this too. Run an Internet search "why does water freeze on top." Try, also, "why does ice float." It looks as if, yes, the air cooling faster is a factor, but the lower relative density of water is the reason ICE IS ALWAY ON TOP OF WATER. Unless, I'm sure, you put a water bottle on top of some super-cooler thingy.

[mike1]

liquid water does not equal water ice cube there einstein

That's all you got?

[Dru]

well if you need the "duh" version -

 

the reason liquid water cannot go below 0c is because it turns to ice if it does

 

so you cool the bottle all at the same rate...

 

the air and water both reach zero but the air keeps cooling while the water stays at zero, because you have latent heat of freezing

 

so when the water does freeze it does so at the air-water intereface because the air is colder than zero and the temperature gradient is steepest across this interface

 

 

the "ice floats" mattp refers to is appicable to lakes butdoes not apply here. a nalgene is too small to develop a thermocline!

[mike1]

Well I for one feed from the “duh” bowl so thank you.

Ok so I know liquid water does not equal “water ice” Mr. Hawking (compliment), must have been thinking about climbing.... Admittedly, I mis-typed my post. My point was to say that ice could be cooled to below freezing temperatures. It has been my understanding that ice or pretty much everything else for that matter could be cooled to absolute zero (-273 C. aka Kelvin)... theoretically...

[dbconlin]

Nalgene Canteen:

 

I had the same problem with even less time/wear. REI replaced mine.

Edited March 9, 2005 by dbconlin

[dbconlin]

EMS sells insulative bottle jackets for half the price. I don't know about the OR jackets, but the EMS one has a nifty velcro strap that you can slide through the back of your harness waistbelt. This effectively holds the water bottle close to your back, so you don't even know its there and keeps h20 from freezing. Especially nice if you are not carrying packs and don't have any other way of carrying water.