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Is there an EPSG code like EPSG:4326 or EPSG:4329, but that specifies (lon,lat) order instead of (lat,lon)?

I've tried exploring the websites http://spatialreference.org and http://epsg-registry.org/

and done a bunch of googling, but no luck so far.

I'm interested in this because the Geoportal Server CSW I'm using assumes (lon,lat) but seems to ignore the CRS, while the PyCSW CSW I'm using assumes (lat,lon), but honors the CRS request. Thus if I had an EPSG CRS for (lon,lat) order, I could specify this to both services and get uniform response.

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    WMS 1.3.0 standard defines "WGS 84 longitude-latitude (CRS:84)". As far as I know there is no EPSG code for that and I do not know where to find official reference for that. It may be in some ISO standard but ISO standards are not free. Unfortunately most services understand only codes in the EPSG namespace so CRS:84 is rather useless.
    – user30184
    Commented Dec 1, 2014 at 22:43
  • @user30184, thanks for the heads up on CRS:84. In the OGC document portal.opengeospatial.org/files/?artifact_id=30575 it specifies the URN for this as urn:ogc:def:crs:OGC:1.3:CRS84 so I guess I can try that and see if anything understands it Commented Dec 2, 2014 at 11:45
  • Well, pycsw doesn't understand it. So I raised an issue at github.com/geopython/pycsw/issues/287 Commented Dec 2, 2014 at 15:10
  • Recently someone asked the EPSG subcommittee to add long-lat order GeoCRS. The request was refused because of ISO 6709 (EPSG items are for display as well as internal use) and INSPIRE CRS spec clause 6. (Disclosure: I'm on the subcommittee).
    – mkennedy
    Commented Dec 2, 2014 at 17:45
  • Can you not just flip the coordinates at an appropriate point in the processing pipeline? Surely that should be the least of your worries.
    – Martin F
    Commented Dec 2, 2014 at 18:09

1 Answer 1

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Okay, based on the comments, I'll provide an answer:

No, there are no EPSG codes that specify geographic coordinates in (lon,lat) order.

The OGC, however, did define a code for geographic coordinates in (lon,lat) order, specified in OGC document http://portal.opengeospatial.org/files/?artifact_id=30575

The full URN for the (lon,lat) ordering of WGS84 coordinates is:

urn:ogc:def:crs:OGC:1.3:CRS84

Of course, whatever software you are using would have to support this. PyCSW will supports this in version 1.10.1 and higher.

See: https://github.com/geopython/pycsw/issues/287

Now there is also (for GeoJSON):

http://www.opengis.net/def/crs/OGC/1.3/CRS84 

and (for KML):

http://www.opengis.net/def/crs/OGC/0/LonLat84
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  • For GeoJSON, the savest option is to leave out the CRS specification. Any software compliant with the GeoJSON spec must interpret the coordinates as WGS84-coordinates in long-lat order if no CRS is given.
    – Joooeey
    Commented May 25, 2023 at 8:48

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