I actually have given some thought to this and looked at this interactive map of potential sea level rise.
https://coastal.climatecentral.org/...urn_level=return_level_10&slr_model=kopp_2017
Although we are on the water, our house is 25 feet above sea level (they didn't stupidly build right on the beach back in the old days). Even inputting the worst case assumptions regarding the rate of rise and the lack of mitigation, we will not need to worry about being inundated for the rest of our lives. There are one or two very low lying roads in town that will be inundated unless a causeway is built, but that will be a minor inconvenience. We have abundant rainfall, rivers, lakes and ponds, so water for drinking and agriculture should not be a problem. We may get a longer growing season, which would be fine by me.
I guess the major downside is the potential for stronger cyclonic storms, although we have historically experienced very few and they have usually petered out by the time they get this far north. A secondary downside is that I probably will need to install central air in the next few years.
In sum, we're still going to stay right here.