https://dailyhive.com/vancouver/victoria-vancouver-rising-sea-levels
Perth, Melbourne, Sydney, Brisbane, GC City, Singapore, Honolulu, SF and Seattle don't seem to be that concerned. They have had no problem building right next to the seawater shore.
https://tidesandcurrents.noaa.gov/sltrends/sltrends.html
https://www.sealevel.info/MSL_graph.php?id=822-116
Apparently, a different set of physics is at work in backward BC. A few centimeters or even a few inches over the course of a century, gives cities plenty of time to prepare. Amsterdam and New Orleans still plan to be up and running. The main concern is to prevent a WW3 scenario.
