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.
Received on Thu Feb 03 2011 - 10:30:01 GMT
