anybody in SCIENCE here?
 

my friend and I are having a discussion about Water

we are trying to find out the behaviour of the temperature of water depending of the depth in the polar waters....


so... when there is a sheet of ice on top of the water, how does the temperature of water vary as we go deeper and deeper starting from the top?



thanx :thumbsup

happy birthday

i've leaned it before,but my memory isn't working now.. peace out!!! :conehead

Water has a very peculiar property. Everything contracts as it gets colder, but once it reaches 4 degrees C, water starts to expand. As this means it also becomes more bouyant, the colder water rises to the surface and freezes, while the lower levels remain above 0 degrees C. The ice also acts as insulation, which is one reason why lakes never freeze solid.

will vary as you go deeper but no solid tempratures, depends how much the water is moving. obviously in calm water all it can do is freze at 0c

i am faitly sure in polar conditions all the water below the ice would be around the same temprature regardless of depth. but i maybe wrong

would you be able to give me a GRAPH of temperature of water (in the polars) vs/ depth?


by the way, let's please think of it as very calm water, not many currents moving, as calm as possible

The sheet of ice is on TOP.. so ofcourse as you go deeper, the temperature is going to vary, simply because the deeper layers are not exposed to the ice like the top sheet of water..

Since water consists of h2o molecules, the deeper molecules are going to have more pressure on them, that might have something to do with the variation of temperature also. I think the molecules on the top would have more space to move around, which doesn't help them entrap any sort of heat.. compared to the water molecules on the bottom which are being pressured upon from all sides and cant move as freely as the top ones

That's the only explanation that i would think of.. maybe there's a bit more to it than i understand right now

more plz :thumbsup

ice is at the top, temperature in the negatives

as you go down, youll hit the sheet of ice which meets the water (liquid), temp here is 0 degrees.

as you go down further, temperature will generally increase

at the very bottom, the temp will be 4 degrees C, as water is most dense at that temp.

Since we're talking salt water here, the water on top will be lower than 0 degrees

If you are talking about salt water, all the water, frozen or not will be below 0 degrees C. When water has salt in it, it will freeze at a lower temperature (and for that matter, boil at a higher temperature than 100 degrees) To answer your question, it is too hard to draw a graph per say of the depth of water vs temperature because it would vary in every climate, size of water mass etc. Some people have said that the water on the bottom would be the warmest. This is furthest from the truth, the water on the bottom would be the coldest it could be without being frozen as it is the furthest from the light, and it wouldn't freeze because it is not exposed to the cold air. It would be the water in the middle that is the warmest.

BTW, you should maybe go back to class..this makes no sense.

And much more bouyant.

Water is at it's most dense at 4 degrees Celcius. If that wasn't the case, we'd all drown.

I can't accept that

hot water goes up, cold water goes down...

in a calm situation, hot water should in no way be trapped between 2 cold waters

or maybe Im wrong?

u're wrong

if you have 4C water and 0C water, the 0C water will go to top because 4C is more dense. thats the anomaly of water.

ah... now it's sinknig in...


but can anybody confirm that some hot water will be trapped in between 2 layers of cold water?

I have no answer other than to say this thread makes me want to pee.

Actually in the high mountains water can get under zero . But it has a high ammount of minerals in it

It takes energy for water to be warm. Cold water is nothing more than water that lacks heat energy. I am not sure you can have a layer of hot water between two layers of cold water because the heat energy would be lost to the surrounding water molecules unless there was an active source of heat energy to keep that pocket warm with the "cold" water taking the energy through convection.


In a swimming pool the shallow water is warm and the deep water is cold so the further you get from an active heat source like the sun the colder the water will be.

When you put ice in a glass and sit it there, the liquid at the bottom is warmer than the liquid at the top because the molecules at the bottom do not contact the heatless molecules at the top. But if that glass were let's say 3 miles deep then there would be no source of heat to warm those molecules in the first place......


So I am going to say it all depends on the temperature of the air up top, the amount of sun that ever shines through the water, the absence of any geo thermal energy and water currents from warm places. If the water is still and there is no energy from the sun then you will have relatively the same temperature of water from top to bottom. the source of the most active heat removal would be at the top.

This was a great question!!!!