On 18/02/2018 13:15, Norman Lynagh wrote:
An interesting read here

https://www.nasa.gov/feature/goddard...sea-level-rise
-accelerating


I suppose it's no great surprise but it certainly is very worrying and
is potentially far more important than all the political shenanigans
that fill the news media. I wonder if there's a backroom team somewhere
in Whitehall trying to devise a plan for an orderly abandonment of
Central London before the end of the century. It might eventually come
to that. There's only so much water that can be kept out. I won't be
around to see the potential problem becoming reality but my
grandchildren might well be.


That reminds me I must get back to
https://www.aviso.altimetry.fr/en/da...sea-level.html
unfortunately the Jason-2 satellite had to have its orbit shifted
outwards and public outputting of data has still not recommenced, but it
looks as though Jason-3 output now has enough output to concattenate to
the previous Jason2 data, seemingly compatible.
As it stood before abandoning that curve-fitting.
For Aviso/Jason-2 data as of 20 Dec 2016, public access 13 March 2017,
from a suite of a few hundred curve types to try, the best R^20.998
fit was for exponential curve type (soon gets alarming not so far into
this century)
Aviso plot (y cm as in Aviso plots and scaling, and years where x=0 for
year 2000)
y=2.1465 - (2.00209)*(1 - e^(+0.07779*x))

The situation has apparently improved since end of 2016, all those nasty
El-Nino effects etc producing a very bumpy plot, ie not so steeply
exponential.

Tide gauges also problematic as they may as well be mounted on a
water-bed , as the ground is not fixed. Currents and gyres , salinity
etc change in the oceans , also , upsetting local land-bordering
mean-sea levels.
From BODC data for Lerwick , between 1957 and 1999 mean sea level has
only risen 30 mm relative to their rising land , isostatic rebound
there. But for Portsmouth between 1962 and 2002 , sea level relative to
sinking Portsmouth then 170mm a rise (contra-rebound to compensate for
rising Scotland).

May as well add a link, as relevant.
An expert on this stuff , next month Southampton, giving a talk in the
open-to-public series of science talks I run
http://www.diverse.ip3.co.uk/scicaf.htm