A scientific explanation please! If ice has a volume greater than water then why would ...?

Question

the polar icecaps melting cause sea levels to rise?? It should be the exact opposite. If you freeze a bottle of water it expands.
Just would like to know where the global warming crowd is coming from on this.
I believe in localized warming caused by concrete, blacktop, lack of trees etc, but global??? In any realistic view they cannot accurately predict weather patterns from year to year. What makes me think they can predict what the earth will do in 50 years? There are a vast number of variables to be factored in.
But I would like to know about the ice.
Any takers with real knowledge???

Answer 1

Aside from the very good answers given by others, there is also the simple fact that there is an awful lot of ice that is currently on land, as opposed to sitting on the water. It covers Antarctica and Greenland at least, probably bits of Canada and Russia too. If all that ice melts, then it will all add to the volume of water in the oceans.

Answer 2

Whoa folks! Let's think this through, because I'm not sure about this: When water is frozen, some aspect of the phase change causes it to expand to a less-dense form. However, it still has exactly the same mass. So imagine an icecube floating in a glass of water. 90% of the icecube is under water, 10% above. The icecube melts. As it does, it returns to it's previous denser state. The 10% that was above the water level now "fits" exactly into the volume that was previously taken up by 10% of the 90% that was below the water level, and that 90% now fits into 90% of its frozen volume. In other words, the water level doesn't change!

...so now of course, I have to throw a glass of water in the freezer for a few hours to see if I'm talking out my *** or not. I'll get back to you. Of course, what was mentioned by others about the land-born ice still applies, once it made its little melted way to the oceans.

Gary H

Answer 3

An equivalent amount of ice does have greater volume than water, but a small percentage of that volume is not in the water, it's in the air. When we look at that system, the body of water is what you're looking at, the air needs to be accounted for if you want to look at things on an even scale with a closed bottle.

If ice did not float and still had a greater volume than water then your assumption would be correct provided no mountain of ice got above water level. Then melting the ice would lower water levels.

So there's basically two things to account for. 1) The increased volume of the ice, 2) The volume of the ice that's above the water. I don't know the exact numbers, but the volume of the ice that's above water is greater than the ice's increased volume which is why water level drops if it's comprised of more ice.

Answer 4

Even though it is a greater size, it is floating, When it melts it causes the water to rise because more water is being added which is less dense than Ice. So if the temp continues to rise, the same rate that it has rose the past ten years, then they can calculate what it will do in the next 50.

Answer 5

Republican Response: The polar icecaps are not melting. Sea Levels are not rising. There is no global warming. We will win in Iraq. Evolution is bunk...etc.etc.

Answer 6

All the ice that is melting is above ground, so if a mountain of ice melts it will rise the water level every where

Answer 7

Fill a glass with water, float an ice cube on top. When the ice cube melts, the glass will over flow. Because ice floats on top of the water when it melts it becomes part of the water reising the water level.




floats o

Answer 8

I agree with the other answers......... that the ice caps are holding great volumes of water. What would be neat is if it does happen. It would solve allot of problems because government would not be the same~
Peace

Answer 9

since extra water is added the sea level rises

Answer 10

if the ice caps were flat, you'd be right. They are not. They rise up out of the water in places hundreds of feet.