That's the main point Tom, because it's happened before, only we didn't recognize it nor were we "advanced" enough to deal with it. More people live at the water's edges now than ever before... and possibly more now than have lived there all together since the dawn of the Agricultural Age.

That's where our problem lies, in the impact it will have on those people. I'm guessing many of them will be able to move to the newly flourishing Sahara Savannah. As they say, it's not the heat, it's the humidity... and once the icecaps melt back a bit, there will be more moisture for rain on the currently arid areas of the world.