Seems likely that the "Bathtub Model" we have in our heads is all wrong, and sea-level change is going to be highly variable in different parts of the planet. Go and watch one of Jerry Mitrovica's videos[1] to get a good idea... According to his models, some places will likely see sea-levels fall by as much as (iirc) 25m, to others where sea-levels will rise by 5 to 8m by the end of this century. Goodbye ports, goodbye containerised shipping, goodbye global trade.
Thanks. He isn't actually saying these numbers (-25 m, 8m) are expected in 2100, he's stating that the peak higher sea level in the older but comparable times (that is during https://en.wikipedia.org/wiki/Eemian around 115 kyears ago) was up to 7 meter higher on the extreme points. Which is a good illustration that the "bathtub mental model" is false. The Intergovernmental Panel on Climate Change (IPCC) is much more constrained to cite that, they present the following (the 2013 results):
The worst projected total average increase at 2100 is around 40 cm if we do some corrections in our fossil fuels use and around 80 cm (on average) if we don't (so called "business as usual", they technically call it "RCP8.5" (1)). The local increases (which we now know can be significantly different) are drawn with the scale up to around 1 m for the "some corrections scenarios" if I understood. But it will go up afterwards for hundreds of years, and it can't be stopped.
Mitrovica believes these are too conservative as even the current measurements already hit the upper bounds. It seems anyway the world is more or less behaving in the "business as usual" sense regarding the fossil fuels.
1) https://en.wikipedia.org/wiki/Representative_Concentration_P... It's worth always looking at the RCP8.5, as that's what's going to happen if no significant changes happen. It's not "the most improbable" but "the most probable if nothing changes" and I admit I personally tend to see the graph with more paths as "OK this one is the highest, it's extreme" when it's the default one!
The IPCC 2nd report came out in 1995. They mention "...a rise in sea level of 30 cm to 1 m by the year 2100."
Seems a bit conservative given current sea level rise, but I suppose they have to go with something that everyone will agree to.
Back in the day I read a book that told the story of how a boy discovered that the old vagabond who skulked about his farm was actually the mighty Belgarath the Sorcerer.
[1] https://www.youtube.com/watch?v=RhdY-ZezK7w