I'm not saying it's a good idea, I'm saying it's a theoretically possible idea in the face of an extinction-level event.
(I'm trying to find a sea rise map that looks right by eye and not having much luck. Here's the North Atlantic at 10m[1]. Surely that's not enough flooding?)
[1] https://coastal.climatecentral.org/map/4/-10.3532/51.4503/?t...