GeospatialOntology - coordinate reference systems

[dr-shorthair]

The CCO GeospatialOntology includes some elements for a partial implementation of coordinate reference system definitions.

Coordinate reference systems are tricky things. There is a long history and strong community practices around them. ISO 19111:2019 captures current practice, to which the very large and very well known EPSG Geodetic Parameter Dataset registry conforms.

There is a fairly advanced project underway to develop an OWL ontology that implements this model - see https://github.com/opengeospatial/ontology-crs.

There is also a widely used implementation in WKT - see https://docs.ogc.org/is/18-010r7/18-010r7.html or https://en.wikipedia.org/wiki/Well-known_text_representation_of_coordinate_reference_systems .

It would be a very ambitious undertaking to re-invent these independently from the geospatial community. Better to join forces I think.

[alanruttenberg]

See also, #184 #147

[dr-shorthair]

I don't feel I can comment on the Directive vs Descriptive question in #147

My particular concern is the absence of an obvious connection to ISO 19111:2019, which is the current standard for Geospatial Coordinate Reference Systems.

Following this standard, a normal CRS is built up from (i) a coordinate system (the axes, in terms of their labels, directions, order, and units of measure) + (ii) a geodetic datum (which anchors the CS to the earth). The axis labels for geodetic systems are not only latitude-longitude, but may also be northing-easting, southing-westing (yes really!), elevation, height, depth, yadayada. I'd be more comfortable if these terms and structure was visible in the GeospatialOntology, and probably if you just had the top classes and then delegated the detail to an existing authority (e.g. EPSG).

Then there are so-called 'engineering' CRS which are local systems usually based at a site, and 1-D (linear) reference systems particularly used by utilities (pipes, roads, wires) and for geophysical and environmental surveys (boreholes, flightlines, traverses).