I once sat in a train opposite a professor of something-or-other-to-do-with-this from McGill Univ. He said that he asked his first year students to calculate how much sea level would rise if just Greenland's ice all melted. I guessed a metre ot two. He said ten metres!
That would put much of Liverpool (except the hill with the cathedrals on it - did they know something?) and all of south Lancashire underwater, let alone vast tracts of East Anglia & the Fens.
Bangladesh. Where they're less able to cope with it than we are.
I can't help thinking (not having done the calculations, though) that expansion of the upper (thermally less stable) layer of the oceans would have a bigger effect.