Quote:
| The Arctic Ice Sheet already has ocean under it. Antartica has mountains. Only Antartica would raise the sea level, since the ice in the Arctic would fill in for water. |
That's not necessarily true. Water volume expands as it's heated, once it's more than 5 degrees celsius. If the subsequently melted ice becomes water with a temperature more than 5 degrees celsius, then it begins to raise the water level as it expands.
As such, the ice caps don't even need to melt for sea levels to rise. As the global temperature increases, water's volume naturally expands.