Re: Arctic Ice: 410,000 Square Miles More Than Last Year

On Jul 28, 3:16 am, Rumpelstiltskin
<PleaseDoNotReplyByEm...@xxxxxxxxxxx> wrote:
On Mon, 28 Jul 2008 03:34:10 -0700 (PDT), JCE <jcbepst...@xxxxxxxxxxx>
wrote:

On 27 juil, 23:07, Rumpelstiltskin
<PleaseDoNotReplyByEm...@xxxxxxxxxxx> wrote:

There are lots of lakes in Antarctica where ice floats
on water below, but Greenland doesn't have the same
topography. Any meltwater could easily escape along
the coasts.

The February issue of Scientific American has
an extensive article on "Sea-Level and the Threat
from Sliding Ice Sheets.

A complete melt down of Greenland would raise
sea levels by 24 feet

My 20 feet ballpark calculation was pretty close
then.





If the West Antarctica ice *** melting that
would be 16 feet

If the East Antarctica ice *** melting
that would be 170.

Since its formation (50 million years ago?)
has not melted down. However large parts
of Greenland have and also West Antarctica.

None of these full meltdowns are possible
in our lifetimes but a 1-3 meter rise in the
sea levels is possible within 100 years.
None of the posters on the internet
will be here then either.

I don't agree that it's "not possible". The
earth is already warming faster than had been
thought possible a few years ago. We really
don't know what we're getting into here. The
earth has not been subject to the array and
amount of pollutants in the atmosphere that
we're pumping in now, within past human
history . The earth has been very different at
other eras, and has likely been suddenly
different at one or more of the half dozen
great extinctions in its history. Those
extinctions happened in a geological instant.
The whole of recorded human history is less
than a geological instant, but this era looks
like another great extinction. The extinction
rate is already plainly dramatic, with most
amphibians and even whole species of
amphibians, whose porous skin is particularly
susceptible to atmospheric contamination,
gone already. I've been hearing lately that
the insects, not just the bees, are
disappearing too. On a radio program
yesterday, callers-in agreed that the amount
of bug splatter on their windshields seemed
to be much lower than just a few years ago.

The only event we are likely to see
is the disappearence of the summer
sea ice in the Arctic seas by 2020.

This will not effect sea levels

No, that won't. The volume of
water below the water line in floating
ice is by necessity equal to the amount
of water that would be made if the ice
melted. Continental rock is about
five times heavier than ice though, so
if continental ice melted or slid into
the ocean, isostatic rebound of the
land on which it used to sit would
only compensate for a fifth of the
weight of the ice, so four fifths of it
would contribute to raising sea levels.

I don't think that your idea of floating ice applies here. Ie that of
the ice over the ocean, 9/10s come from the ocean. Rather IIRC most of
that ice is snow deposited on salt water ice? Does anyone have any
data on this? Ie that most of the ice over the ice pack over ocean is
fresh water rather than salt. Surely some scientist has drilled into
and through the northern icepack to make this determination? We need
to remember that ice supports a lot of weight. And in my opinion, even
more if say, on the sides of a river where the ice could be thicker.
Then the arch type of structure would transmit the downward forces on
the ice sidewards to the embankment. Similar structures throughout the
ice pack over water would hold up a lot of ice from packed snow over
thousands of years.

The ice would not break up from the sidewards forces because it
covered the whole area with very little open ocean. You might think of
this structure similar to an ice plug in an upwardly positioned
funnel. The forces above the plug are redirected towards the sides of
the funnel. Sail boat enthusiasts might appreciate this redirection of
force from sailing into the wind. Scientists who overlooked this in
their melting ice models will have a much more rosy result of a small
rise in the ocean levels.

In some parts of the world it is estimated that the oceans dropped
about 400 feet in previous ice ages. This is when heavy ice sheets
covered most of the northern parts of the continents.Let's hope that
scientist's prediction of a moderate rise this time holds true.
.

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