> In fifty years, when economies are collapsing due to rising sea levels...
Sea level rise has not accelerated in twenty years of measurement[0] (depending how you cherry pick the analysis it is actually decelerating[1]) and will add 160mm or about half a foot if the next fifty years is the same pace as the last twenty. I don't think that's going to collapse very many economies.
I hope you realize that choosing twenty years is itself cherry picking.
Here's a fun exercise for you: what would the real second derivative have to be in order for it to be clearly positive over a mere twenty year interval?
Sea level rise has not accelerated in twenty years of measurement[0] (depending how you cherry pick the analysis it is actually decelerating[1]) and will add 160mm or about half a foot if the next fifty years is the same pace as the last twenty. I don't think that's going to collapse very many economies.
[0]http://sealevel.colorado.edu/ [1]http://climatechangedebates.com/sea-level-stats-longer.php