I don't see it being 6 feet, either, given that Global Warming is logarithmic - if CO2 rises at a constant rate, the temperature will rise more and more slowly as time goes on.
Accurate (calibrated) sea level rise has only been “measured” since the 1920’s: 1920 - 2000, the rate was stable at 2.2 - 2.4 mm per year. It is a value I trust based on all the numbers from around the world for “global average sea level rise”.
Now, 2.3 - 2.4 mm per year =
1 inch per decade,
10 inches per century,
1 meter in 400 years.
Now, for a great change they (NPR propagandists) actually “started to get” their message right! They did actually use 8 inches higher by the end of the century! Then NPR went off the deep end and used up to 6 feet, and “millions of people displaced” with the scary “increasing rates of sea level rise!” They just can't use the actual rates and the actual exaggeration their ownders demand.
BUT! Local areas rise and drop substantially more - or much less!) than this global average: Baytown TX dropped 6 feet in only 8 years when they pumped down their aquifer for water, then pushed the land back up again when they wised up. Taiwan, Philippines, Hong Kong, many small islands see the same thing. The very tip of Manhattan is going down while Hudson Bay shoreline base rocks are going up. So Manhattan is dropping at 3.1 mm per year, Hudson Bay is going up! (Sea level rise is negative, if you will!)
The Smithsonian's Air and Space Magazine recently turned that 3.1 mm per year sea level rise into 3.1 feet per decade, by the way. No apologies or explanations yet either.