From: Spike Jones (spike66@attglobal.net)
Date: Sat Jun 30 2001 - 20:59:04 MDT
zeb haradon wrote:>
> >Question: if all the ice on earth melted, how much would the seas rise?
> >spike
>
> Pour some water into a glass. Put some ice cubes into the glass. The ice
> cubes will be mostly submerged, but will stick out a little bit. Now fill
> the cup all the way up, so that it is up to the brim with water, and the
> tops of the ice cubes are sticking up over the brim. Now wait for the ice to
> melt. As the ice melts, how much water flows over the brim?
> This should give you your answer as far as the Arctic goes, since the ice is
> floating on the water. I'm not sure about the Antarctic.
Of course the ice contracts as it melts, so the floating ice doesn't matter.
However, zeb, I suspect your ice in a glass test was proposed as
a thought experiment, for under certain conditions the glass will
overflow as the ice melts. If one lives in a high humidity environment,
and starts with ice cold water, then adding the ice, very carefully
raising the ice to the rim of the glass, there should be about a gram of
water condensed out of the air for every 6 grams of ice melted.
More exactly, since 540 calories per gram of water condensed will
absorb heat from 80 calories per gram of ice melted. Try it! I have.
The glass *will* overflow if you control the conditions, and provide
a sufficiently high humidity environment.
I wondered about the question since the A.I. movie did the classic
dystopian runaway greenhouse gag about the torch of the statue
of liberty poking out of the waves. So they were suggesting the
great melting would raise the seas about, what? 80 meters or so?
But when I see something like that I am tempted to shout a Robert-
Bradburyesque "Thats not true!" But I thought this inappropriate for
a crowded theater.
So when I saw it in A.I., I wondered how thick would need to be
the average depth of the ice on Antarctica to raise the seas 80 meters?
My first order estimates are that there is perhaps 2% of the earth's
surface is ice with land under it. If all that melted, then the average
depth of that ice would need to be about 3 km thick to raise the seas
that much. I dont think it is that thick.
As in the case with the waterglass, the warmer water would expand
some. So if we need to account for that in estimating the sea rise in
case of environmental repair caused by increasing CO2. spike
This archive was generated by hypermail 2.1.5 : Sat Nov 02 2002 - 08:08:23 MST