On 24/07/2020 08:31, N_Cook wrote:

But obviously not with the likes of Aviso implying , by continuing to
"fit" straight lines, that everything is hunky-dory.

No-one is remotely suggesting that as far as I'm aware (though linearity
is probably the least-worst generic option unless you have a better
_model_ (not arbitrary function) that the data can be fitted to).

But compounding one piece of arguably bad science (the linear model)
with another piece of bad or worse science (wild extrapolation of a
model with no justifiable connection to the data) is not good, to put it
mildly and lays the results wide open to exactly the criticism I'm making.

It's the huge extrapolation which is the especially bad part of this.
Different data fits can be tried if you're _interpolating_ values within
the approximate range of the dataset but that's clearly irrelevant here
if the aim is to estimate sea level in eg 2100.

What I'm slightly puzzled about is that there clearly must be
professional estimates of future sea level based on a range of carefully
researched models and which are presumably updated at intervals. Why not
devote your energies to publicising and explaining these as new updates
become available - that would be really interesting?