CDO

Hi

I'm using CDO for remapping and I'm confused about how CDO handles geographic coordinates (sphere vs. on elllipsoid). This paper gives a nice overview about the issue:

https://journals.ametsoc.org/view/journals/mwre/141/6/mwr-d-12-00351.1.xml

I'm e.g. using CDO to remap data from a Lambert Conformal Conic projection to a latitude/longitude grid. This requires a PROJ string, which also provides information on the reference system of the input data (ellps=WGS84 vs. ellps=sphere). Let's say my input data is defined on a ellipsoid (ellps=WGS84) and I remap it with CDO remapbil to a latitude/longitude grid. Are the obtained latitude/longitude coordinates now valid for an ellipsoid or a sphere? I guess internally in CDO, all coordinates are assumed to be spherical coordinates - right? I.e. a coordinate system rotation (due to a shifted pole) is for instance performed with spherical coordinates.

To conclude the confusing topic: does CDO assume that spheroidal and spherical are identical (as discussed in the above paper)?

Thanks a lot for your help!