Steve,
Heck, these scientists can't even agree whether sea levels will rise or fall with global warming. Some say the ice will melt meaning more water and higher sea levels. Others point out that most of the ice caps are underwater and ice is less dense than water so in fact sea levels will fall when the ice melts.
Actually, come to think of it, for floating ice both are wrong. Floating objects displace their own weight in water (Archamedies Principle). When an iceberg melts, the volume it will occupy will be exactly the same as the volume of an equal weight of water because that is what the iceberg becomes. So it will shrink into the space that it occupied below the water line causing no change at all in sea level.
Ice over land mass is another story. When it melts it will flow to the sea eventually. I have no idea how much of the world's ice falls in that category.
Dan
EDIT:
whyfiles.org
Ice-sheet insanity. Melting glaciers are
but a trickle of water on the planetary
scale. They're small change compared to
the West Antarctic Ice Sheet, which
holds 3 million cubic kilometers of fresh
water. Were it to melt, sea level would
rise 20 feet, and coastal cities, not to
mention beaches, would be in tough
shape.
Let me make one thing perfectly
obscure
Ice shelves melt all the time, "calving"
icebergs that, no matter how enormous,
do not effect sea level. Because floating
ice displaces the same volume of water
as melted ice, iceberg that formed from
floating ice on Antarctica's vast ice
shelves add no volume to the ocean. |
