We simply cannot do it.
There is no way to validate the models.
We do not have the data.
Sure there is, are you kidding?
The models are valid if they help us advance our political agenda. Are you new?
This is a NOAA webpage which has looked at increments of 50 year sea level trends at many sites across the US. (and world sites if you click around a little)
https://tidesandcurrents.noaa.gov/sltrends/sltrends_station.shtml?stnid=8723170
Click on the tab that says, Variation of 50-Year Relative Sea Level Trends you can look at different gauges around the country for different 50 year averages.
In most cases the 50 year intervals show declining rates of sea levels on the order of 3-5 millimeters which then level back towards the baseline. Thats millimeters over 5 decades! Its all BS!