On 2/3/2011 1:54 AM, Heiko Klein wrote:
I can confirm Davids observation. The European atmospheric models I'm
working with use also unchanged WGS84 (geodetic) coordinates with a
spherical earth.
The proj4 projection library (starting with 4.5, I think) tries to
solve this in the following way (see
http://osgeo-org.1803224.n2.nabble.com/How-to-convert-a-sphere-to-ellipsoid-with-correct-datum-td5486117.html
):
* if input and output projection both have a DATUM set (besides the
ellipsoid) a geodetic/geocentric conversion is done.
* if the datum is missing on any projection (input or output) no
geodetic/geocentric conversion is made
As far as I've seen, the netcdf-java library 4.2 has no code for
geodetic/geocentric conversion, so it follows the models.
correct.
i guess whats missing is a method to convert lat/lon on one ellipsoid to
lat/lon on another?
I don't even know if there is a way in newer CF-versions to set the
Datum, besides the ellipsoid?
I think the only possible thing you can do currently is to set the
ellipsoid parameters.