Can you source these predictions? The timetable matters, for example. If a transition in sea level takes place over a hundred years, it seems reasonable that populations would gradually move uphill.

Also, as land becomes less farmable, other land at higher latitude and elevations might become more so. There's also the increase in vegetation associated with higher CO2 levels that might actually improve some farming.

I don't feel like we should fall into to emotional trap of throwing up our hands and predicting the apocolypse.