the warming, and therefore expanding, of the water itself, NOT by the additional water being freed up by melting ice. This video seems to say the opposite -- that sea level rise is the product of melting ice.

Which is it?

Partly by the expansion of the warmer seas, but mostly by the melting of the polar ice caps. All that water locked up in the ice sheets above sea level, melting and flowing into the oceans. That is a lot of water.

sitting on ground above sea level. When that melts, it all goes into the ocean. That is potentially 27 meters of rise worldwide.

Now, like the mastadons, we can just move inland. But the coasts are where most people live. And a lot of people are going to die in the process because we won't make the move inland until floods force that. And as we have seen with Super Storm Sandy and Typhoon Haiyan, it isn't the average sea level that gets you. it is the fact that the next surge is bigger than the last with no end in sight.

We are way past the point that any of us will live to see the reversal of this problem. The best we can hope for now is to slow it down a little and hope for a more enlightened population after we are all gone.

This picture is something that the younger of us here could see DURING their lifetime with the red spots being underwater.

As Greenland melts, the same thing happens all over the world, including Antarctica, so the total rise possible is about 70 meters.

http://nsidc.org/cryosphere/glaciers/quickfacts.html

if all of antarctica were to melt, that would be 70 meters or so,
but that is not realistic. still, even a few meters would be devastating.

Look how much the consensus has moved even in the past 10 years. This thing is accelerating rapidly. I agree that not every bit of ice worldwide will melt. The highest mountains in the more extreme latitudes will keep some of their glacial ice, and some will remain in Antarctica. And this process that was once thought to span many centuries is now looking like we are talking generations instead of centuries. That still isn't overnight, and most of us will not see Miami go completely underwater, but it is moving MUCH faster than anybody believed possible 20 years ago.

more on the thermal aspect here

and with CO2 and Methane you get something else that the graph goes back to if extended.

enough so that you'd have an ice age.
that is, hundreds of thousands, if not millions, depending on how high we go.
There is no going back on any time scale relevant to humans.