[PROJ] Extent of vertical CRSs

[Javier Jimenez Shaw]

Hi

Recently I found some vertical systems that do not cover properly the
entire area they "should" cover (a country usually) but that their geoid
models do.

One example I already posted here was in Canada for
https://epsg.org/crs_5713/CGVD28-height.html We contacted them (thanks
Even) and they will update EPSG and ISO databases to cover Newfoundland.
https://lists.osgeo.org/pipermail/proj/2023-December/011203.html

But I found more examples:

This example from Switzerland for
https://epsg.org/crs_5729/LHN95-height.html is not as significan (just a
few hundred meters, but it surprising how they missed it in 3 of 4 sides)
You can see them in this mini-GIS link (Just click the "squares" to fit to
each "outlier" bounds)

https://javier.jimenezshaw.com/mapas/?name=st&c=46.7511530,8.6243091&z=8&f=xtra1&b=osm&v=1&e=1&o=100&ed=1&m=&extra_name=swisstopo&extra_url=https%3A%2F%2Fwmts100.geo.admin.ch%2F1.0.0%2Fch.swisstopo.pixelkarte-farbe%2Fdefault%2Fcurrent%2F3857%2F%7Bz%7D%2F%7Bx%7D%2F%7By%7D.jpeg&d7=7mnpck,zgn5v,West,8,008000,3;0,snb&d7=7kse2q,1hopil,South,8,800080,3;f06,-hw&d7=7pjafh,1qgtba,East,8,ff00ff,3;-6k,-fzs&y7=7wncbk,zhfnk,Extent%20EPSG%3A1286,8,ff0000,3;-buixs,0;0,qyxpc;buixs,0&y7=7mo4q6,zheng,West,8,ffa500,3;-wle,bx;-9r7,-k1b;1u4,-2zb;rbd,-7m8;je8,ust&y7=7kspwk,1hmppz,South,8,000080,3;38c,-g9y;-20,2yab;-45l,-9rq;-adz,-2zb;-gm,-ijo;7pz,-lh6;5dl,-nn5&y7=7pj8of,1qgdhh,East,8,a68c2b,3;ka,ckf;198,387;-izq,lh;-ciw,-6n0;-6dc,-9lr&ga=0

Another example is Japan with
https://epsg.org/crs_6695/JGD2011-vertical-height.html that does not
include the island of Okinawa (among others), that is covered by the geoid
model in PROJ-data. (here the distance is big. I didn't know that Japan
reached 24 deg latitude)

In Ireland they leave some islands out of
https://epsg.org/crs_5731/Malin-Head-height.html in the west, like Munster,
also covered by OGM15_Malin tiff file.

*The problem* is that PROJ is not using the geoid model out of the area of
use of the vertical CRS.

One option is to contact the agencies to correct their area of use in EPSG
(does anybody know how to contact Swiss, Japanese or Irish agencies in this
case?). I have seen many EPSG updates that are just increasing 0.01 deg an
extent.

Would it make sense to be more flexible on the vertical transformations?
Just contacting the local agencies is enough?

Cheers,
Javier.

PS I am surprised that some countries do not pay more attention to the
extent of their countries. I thought it was a geopolitical topic.
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