worldwide flood levels

Factual Questions
1

i just finished reading the drowned world by JG ballard.
which got me to thinking: the prenmise of the book is set 50 years after the polar ice caps have melted and flooded just about everywhere below + above north and south pole due to massive solar flare ups, and the earths temperature continues to rise.so:
if this did happen, how high would the water level rise and which parts of the world would be underwater?
ballards book, set above flooded london has the water level at around 10 storeys high on buildings-im not sure how far this is above current sea level.surely even if the entire ice caps melted it wouldnt get this high?

or would it?

2

The USGS esitmates a maximum of 80.44 meter rise in sealevel is possible. They divide it up into the various collections of ice. Please note they make no predictions here on how likely such an outcome might be, just the potential.

I live about 30 meters above sea level, although the ground floor of my building is only 1m. I’m doomed.