it looks as if you have completely misunderstood a part of the physics involved. Even if a very large floating chunk of ice, as large as the Arctic polar cap melts, the sea level doesn't really change. You can try that with a drink and a bit of ice.
Only if the ice is supported by land, as McGrath has alluded to, its melting can rise the sea level. So the melting of the Antarctic polar cap or the becoming green again of Greenland would have a large influence.
It wasn't sure whether the plural 's' in the 'caps' in your response to Teribus was a cleverly hidden hint that he should also look at the other pole as McGrath's interpretation was or whether you did not understand Teribus' point at all. I now think you didn't understand his point.