Sea Levels are up 10 to 12 inches since 1880, It should be noted the 1880 is at the end of the mini Ice age.
The belief is over the next 30 t0 40 years it will go up another 10 to 12 inches.
It is going to be a real problem, but it is mostly manageable. Which is now highly populated shoreline will be gone and people and buildings will have to go or be fortified to handle the new conditions.
We don't even know what conditions are best for most life on planet Earth, We do know that Ice ages are not.
We may today be in the goldilocks zone, or it could be where we will be in 20 to 30 years.
We have increased fuel mileage, better lighting, cleaner power plants, more efficient homes and will continue to improve on all of that, but China, India and others are going to wipe out all of those gains and then some. Lets be honest the people leading the push are willing to do nothing. Al Gores mansion uses 21x times the average persons home power. Flying private jets is a massive waste. Almost none of them will make the changes needed to slow the effects. We are doomed to dealing with those effects, and we will.