by prof. growhener
Just a little rise in sea level might change this place dramatically
If ice melts in the a glass the level does not rise, but places such as Antarctica and Greenland consist of land ice, which when melted will increase the sea level globally.
Barry's Response -
Yes, professor. That is a major concern. It is one Al Gore stresses in An Inconvenient Truth.
An object, when placed in water will displace the lesser of its volume or its mass of water. Its volume if it sinks, its mass if it floats. Floating ice
is already displacing its mass, so when it melts, its mass simply integrates with the remaining water and there is no change in displacement.
Ice that has any of its mass propped up on solid ground underneath will contribute its previously supported mass to the total of the water body it drains into upon melting. This constitutes the majority of Antarctic, Canadian Archipelago and Greenland ice, but not the rest of the Arctic ice, which is sitting on the Arctic ocean.
One exception: If the ice is forming a natural bridge over the water (which would remain in position if the water were drained), then it's not really floating. Its weight is supported by the neighbouring ice, which is supported by the land it rests upon. The meltwater from this situation would raise the water level.Search
this site for more information now.