[thredds] TDS 4.2.x WMS support for EPSG 3857, 3408, and 3409 CRS [was: Re: EPSG 3857 (google maps / 900913) in TDS 4.2.5]

• To: thredds@xxxxxxxxxxxxxxxx
• Subject: [thredds] TDS 4.2.x WMS support for EPSG 3857, 3408, and 3409 CRS [was: Re: EPSG 3857 (google maps / 900913) in TDS 4.2.5]
• From: Ethan Davis <edavis@xxxxxxxxxxxxxxxx>
• Date: Mon, 04 Apr 2011 17:18:23 -0600

Hi all,

I have a TDS snapshot available at

ftp://ftp.unidata.ucar.edu/pub/thredds/4.2/snapshot/thredds.war

This snapshot supports all three of the CRS listed in the WMS
GetCapabilities document that weren't working: EPSG:3857, EPSG:3408, and
EPSG:3409. As discussed in recent emails, this involved adding the WKT
for these three CRS to the epsg.properties file in WB-INF/lib/epsg-wkt.jar.

However, the WKT for EPSG 3408 and 3409 (given below) which came from
the EPSG database (thanks Jon) was not successfully parsed by the
GeoToolkit library. The error message was:

    Error in "AXIS": Parameter "orientation" is missing.

After google-ing around a bit, I tried a few changes to the "Easting"
and "Northing" AXIS sections but only had success when I completely
removed these sections. By success, I mean that I don't get an exception
when making a request with either of these CRS and I get a reasonable
looking image back.

However, not really understanding these CRS or their WKT, I'm a bit
uncomfortable with this solution. If anyone has a better solution than
removing these two AXIS sections, please let me know. Or, if anyone can
verify that these CRS are working properly, that would be great as well.

Thanks,

Ethan

----------
EPSG:3408

PROJCS["NSIDC EASE-Grid North",
  GEOGCS["Unspecified datum based upon the International 1924 Authalic
Sphere",
    DATUM["Not specified (based on International 1924 Authalic Sphere)",
      SPHEROID["International 1924 Authalic Sphere", 6371228.0, 0.0,
AUTHORITY["EPSG","7057"]],
      AUTHORITY["EPSG","6053"]],
    PRIMEM["Greenwich", 0.0, AUTHORITY["EPSG","8901"]],
    UNIT["degree", 0.017453292519943295],
    AXIS["Geodetic latitude", NORTH],
    AXIS["Geodetic longitude", EAST],
    AUTHORITY["EPSG","4053"]],
  PROJECTION["Lambert Azimuthal Equal Area (Spherical)",
AUTHORITY["EPSG","1027"]],
  PARAMETER["latitude_of_center", 90.0],
  PARAMETER["longitude_of_center", 0.0],
  PARAMETER["false_easting", 0.0],
  PARAMETER["false_northing", 0.0],
  UNIT["metre", 1.0],
  AXIS["Easting", "South along 90°E"],
  AXIS["Northing", "South along 180°"],
  AUTHORITY["EPSG","3408"]]
----------
EPSG:3409

PROJCS["NSIDC EASE-Grid South",
  GEOGCS["Unspecified datum based upon the International 1924 Authalic
Sphere",
    DATUM["Not specified (based on International 1924 Authalic Sphere)",
      SPHEROID["International 1924 Authalic Sphere", 6371228.0, 0.0,
AUTHORITY["EPSG","7057"]],
      AUTHORITY["EPSG","6053"]],
    PRIMEM["Greenwich", 0.0, AUTHORITY["EPSG","8901"]],
    UNIT["degree", 0.017453292519943295],
    AXIS["Geodetic latitude", NORTH],
    AXIS["Geodetic longitude", EAST],
    AUTHORITY["EPSG","4053"]],
  PROJECTION["Lambert Azimuthal Equal Area (Spherical)",
AUTHORITY["EPSG","1027"]],
  PARAMETER["latitude_of_center", -90.0],
  PARAMETER["longitude_of_center", 0.0],
  PARAMETER["false_easting", 0.0],
  PARAMETER["false_northing", 0.0],
  UNIT["metre", 1.0],
  AXIS["Easting", "North along 90°E"],
  AXIS["Northing", "North along 0°"],
  AUTHORITY["EPSG","3409"]]
----------

• Follow-Ups:
  • Re: [thredds] TDS 4.2.x WMS support for EPSG 3857, 3408, and 3409 CRS [was: Re: EPSG 3857 (google maps / 900913) in TDS 4.2.5]
    • From: John Maurer

• References:
  • Re: [thredds] EPSG 3857 (google maps / 900913) in TDS 4.2.5
    • From: Jon Blower
  • Re: [thredds] EPSG 3857 (google maps / 900913) in TDS 4.2.5
    • From: Ivan PRICE