Think of the ice dam that kept Lake Agassiz in place only on a far larger scale.
At some point this structure would have to break, either due to melting, or earth movements. When that happened the entire mass of melt water, and residual ice, would immediately rush to the North, but in such vast quantities that the wave forms could not be contained locally. A soliton, or near soliton would be created around the perimeter.
This soliton would move North until it crashed into a continental land mass. Think of the Cheetah ~ they are so genetically identical it is thought that 14 thousand years ago (about the time of the Antarctic melt) that all of their kind but one mother with two kits were destroyed. They live ONLY in Southern Africa! Most everything in the South up to the Khalahari desert would probably have been destroyed by this soliton. A mother cheetah in a deep cave could have crawled out to a strange world for sure.
To the East, the Soliton would have devastated everything from Kenya to Indonesia along the coast, and as far inland as a 2 mile high mountain of water can go.
Further East, and North of the Equator, converging solitons might have raised even higher ~ maybe to 4 or 5 mile heights. They would crash into Japan, Siberia, Beringia, and the North American coast all the way to Baja.
This could be a very good reason why we don't have any good evidence of early human habitation in North America! South America would be as thoroughly devastated.
Even high civilization would be ground up like so much dust.
So, who would be left after this event? Well, people in Central Africa, those in Northern Europe and Asia, and folks in the Himalayan highlands would still be around.
And, if you take a good look, that's who we've got these days ~
BTW, I'm not a geophysicist by any means but I've been thinking about this problem for many years as a result of reading an analysis that has the entire Antarctic meltoff occuring as a slow runoff that creates a gentle 66 foot rise in the ocean that took hundreds of years.
The article at http://news.nationalgeographic.com/news/2003/03/0317_030317_iceshelf.html touches on the idea, but it still projects a slow runoff over 200 years. This does not affect the propagation of the soliton! The soliton wave moves North rapidly using the deep ocean medium in which it finds itself. The body of water that generated it follows slowly behind raising the ocean levels by 66 feet. Unfortunately for the surviving humans, the soliton destroyed the existing shorelines in their favorite warm climate estuaries.
No doubt the survivors would have noticed both the passing of the soliton and the subsequent flood. I suppose this would be considered a Universal Flood.
Interesting theory. That would be some wave. Bet some surfers are sorry they missed it ....