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[netCDF #RFM-852616]: cdm validator

Hi Sue:

Sorry, you've found a bug (see below) :

> Here is the file in lambert azimuthal equal area projection
> as promised over the weekend.  Can you determine why it does
> not show useable gridded data in your cdm validator.
> 
> According to the CF document, in Appendix F, section F.3, the LAEA
> grid mapping requires the following parameters:
> longitude_of_projection_origin
> latitude_of_projection_origin
> false_easting
> false_northing
> 
> However according to the unidata website you sent, it expects
> additional metadata in the projection variable( standard_parallel and units).
> Is this the problem or a typo? If it IS the problem:
> 
> (1) Why would the "standard parallel" be required for this projection.
> It doesn't appear to be required by the Proj.4 LAEA projection which
> is referenced in the CF-1.0 document.

"standard parallel" is a cut and paste error. there is no such parameter for 
lambert_azimuthal_equal_area.
this was preventing the projection from correctly being created. I will put out 
a fix tommorrow. 

> 
> (2)Why should the grid mapping structure contain the "units" if
> they are already defined in the projection arrays (x0 and y0)?

units are optional. in fact this is being deprecated in the 4.0, so best to not 
use it. always use the units of x and y coordinate axes. in your case, easting, 
northing are 0 so issue is moot.

> 
> Thanks for all of your help. We appreciate it!

thanks for debugging!


Ticket Details
===================
Ticket ID: RFM-852616
Department: Support THREDDS
Priority: Normal
Status: Open