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[netcdfgroup] Encode an azimuthal equidistant projection in NetCDF conversion
I'm trying to do Azimuthal Equidistant in CF-compliant NetCDF, but I didn't get the correct projection. If you compare the first two information (gdalinfo) you see there is no `AUTHORITY` and also `PROJCS`, `GEOGCS`, `DATUM`, `SPHEROID` are unknown. 

I followed this link to set the set the projection:
Mapping from CF Grid Mapping Attributes to CRS WKT Elements <https://github.com/cf-convention/cf-conventions/wiki/Mapping-from-CF-Grid-Mapping-Attributes-to-CRS-WKT-Elements> 

This is the original projection which I want to save it to NetCDF.

|
Sizeis8000,8000
CoordinateSystemis:
    PROJCS["Azimuthal_Equidistant",
        GEOGCS["WGS 84",
            DATUM["WGS_1984",
                SPHEROID["WGS 84",6378137,298.257223563,
                    AUTHORITY["EPSG","7030"]],
                AUTHORITY["EPSG","6326"]],
            PRIMEM["Greenwich",0],
            UNIT["degree",0.0174532925199433],
            AUTHORITY["EPSG","4326"]],
        PROJECTION["Azimuthal_Equidistant"],
        PARAMETER["latitude_of_center",53],
        PARAMETER["longitude_of_center",24],
        PARAMETER["false_easting",5837287.81977],
        PARAMETER["false_northing",2121415.69617],
        UNIT["metre",1,
            AUTHORITY["EPSG","9001"]]]
Origin=(4800000.000000000000000,1800000.000000000000000)
PixelSize=(75.000000000000000,-75.000000000000000)



|


and this is what I got:

|
Sizeis8000,8000
CoordinateSystemis:
    PROJCS["unnamed",
        GEOGCS["unknown",
            DATUM["unknown",
                SPHEROID["Spheroid",6378137,298.257223563]],
            PRIMEM["Greenwich",0],
            UNIT["degree",0.0174532925199433]],
        PROJECTION["Azimuthal_Equidistant"],
        PARAMETER["latitude_of_center",53],
        PARAMETER["longitude_of_center",24],
        PARAMETER["false_easting",5837287.81977],
        PARAMETER["false_northing",2121415.69617]]
Origin=(4799602.500000000000000,1800037.500000000000000)
PixelSize=(75.000000000000000,-75.000000000000000)
|




here is the code that I extracted the projection:

|
# Extract Projection info from tiff
    ds=gdal.Open('sample.tiff')
    prj=ds.GetProjection()
    srs=osr.SpatialReference(wkt=prj)


# Create container variable for CRS
    crso=nco.createVariable('crs','i4')
    crso.grid_mapping_name='azimuthal_equidistant'
    crso.projected_crs_name=srs.GetAttrValue('PROJCS')
    crso.geographic_crs_name=srs.GetAttrValue('GEOGCS')
    crso.horizontal_datum_name=srs.GetAttrValue('DATUM')
crso.latitude_of_projection_origin=srs.GetProjParm('latitude_of_center') crso.longitude_of_projection_origin=srs.GetProjParm('longitude_of_center') 
    crso.false_easting=srs.GetProjParm('false_easting')
    crso.false_northing=srs.GetProjParm('false_northing')
    crso.longitude_of_prime_meridian=0.0
    crso.semi_major_axis=6378137.0
    crso.inverse_flattening=298.257223563
|



Does someone know how to get the correct projection?
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