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[netCDFJava #RIZ-451320]: why can't this be read as a grid



Its on 4.3.22, will be released soon.

> John-
> 
> I contacted the CDO developers and apparently this is fixed in the
> latest version of CDO (1.6.3), but I'm stuck at 1.6.2 until it makes it
> out to macports.  I see that you fixed this in the 4.5 branch.  Can it
> get merged into the 4.3.22 branch so I test it out?
> 
> Thanks.
> 
> Don
> 
> On 5/17/14 1:03 PM, Unidata netCDF Java Support wrote:
> > Hi Don:
> >
> > We will have a look to see if we can safely disambiguate the conflicting 
> > info. Can you contact CDO and let them know they have a bug?
> >
> > thanks
> > John
> >
> >> Dear Lansing, John and Ethan-
> >>
> >> Thanks for your responses.  I had read the CF conventions about the
> >> standard names and understand that grid_latitude/grid_longitude are the
> >> standard names for a rotated pole projection.  That's why I indicated to
> >> Lansing that this was the problem.
> >>
> >> However, as Ethan points out, the units are wrong for a rotated_pole and
> >> there is no grid_mapping_name variable associated with the tas variable.
> >> So, tas is not defined by a rotated pole coordinate system.
> >>
> >> The original grid is a gaussian dataset and the original standard names
> >> were latitude and longitude, so CDO does change the standard names.
> >>
> >>  From my perspecitve, though, the latitude and longitude variables meet
> >> the requirements for being standard latitude and longitude variables in
> >> CF by the units and axis attributes:
> >>
> >> http://cfconventions.org/1.6.html#latitude-coordinate
> >>
> >> (correct units and axis attributes) much more than for the rotated pole
> >> case (wrong units, no grid_mapping_name).  So, I would still content
> >> that this is a bug.
> >>
> >> Don
> >>
> >> On 5/16/14 4:43 PM, Unidata netCDF Java Support wrote:
> >>> Hi Don,
> >>>
> >>> The use of "grid_latitude" and "grid_longitude" standard names indicates 
> >>> a rotated pole grid mapping (defined in Appendix F: "Grid Mappings" 
> >>> section [1] of the CF spec). But lat and lon have the wrong units for a 
> >>> rotated pole grid (they should be "degrees") and a rotated pole grid 
> >>> mapping is not defined. (Here's the definition for "grid_latitude" [2] 
> >>> from the CF standard name table [3].)
> >>>
> >>> Was the original dataset on a rotated pole grid?
> >>>
> >>> Ethan
> >>>
> >>> [1] http://cfconventions.org/1.6.html#appendix-grid-mappings
> >>>
> >>> [2] "Latitude is positive northward; its units of degree_north (or 
> >>> equivalent) indicate this explicitly. In a latitude-longitude system 
> >>> defined with respect to a rotated North Pole, the standard name of 
> >>> grid_latitude should be used instead of latitude. Grid latitude is 
> >>> positive in the grid-northward direction, but its units should be plain 
> >>> degree."
> >>>
> >>> [3] 
> >>> https://badc.nerc.ac.uk/help/formats/netcdf/cf-standard-name-table.html
> >>>
> >>> Don Murray wrote:
> >>>> It doesn't like the standard_name for latitude and longitude (using ncml
> >>>> to remove them makes the grid readable).  I don't have the ability to
> >>>> remove them in the workflow, and this seems like a bug.
> >>>>
> >>>> Don
> >>>>
> >>>> On 5/16/14 3:35 PM, Unidata netCDF Java Support wrote:
> >>>>> There's confusion somewhere, ToolsUI is looking for a projection instead
> >>>>> of recognizing the lat lon coords.
> >>>>>
> >>>>> -Lansing
> >>>>>
> >>>>> On 5/16/2014 12:55 PM, Don Murray (NOAA Affiliate) wrote:
> >>>>>> New Ticket: why can't this be read as a grid
> >>>>>>
> >>>>>> Hi-
> >>>>>>
> >>>>>> I have a netCDF file that I created using the Climate Data Operators
> >>>>>> (CDO) package by subsetting a larger file.  The original file can be
> >>>>>> read into the IDV/ToolsUI, but the subset cannot (is not recognized as 
> >>>>>> a
> >>>>>> grid).  I don't see anything obviously wrong with the file, except that
> >>>>>> maybe the CDM is getting confused by the use of x and y?
> >>>>>>
> >>>>>> Why doesn't the CDM recognize this as a grid?
> >>>>>>
> >>>>>> Don
> >>>
> >>>
> >>> Ticket Details
> >>> ===================
> >>> Ticket ID: RIZ-451320
> >>> Department: Support netCDF Java
> >>> Priority: Normal
> >>> Status: Closed
> >>>
> >>
> >> --
> >> Don Murray
> >> NOAA/ESRL/PSD and CIRES
> >> 303-497-3596
> >> http://www.esrl.noaa.gov/psd/people/don.murray/
> >>
> >>
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: RIZ-451320
> > Department: Support netCDF Java
> > Priority: Normal
> > Status: Open
> >
> 
> --
> Don Murray
> NOAA/ESRL/PSD and CU-CIRES
> 303-497-3596
> http://www.esrl.noaa.gov/psd/people/don.murray/
> 
> 


Ticket Details
===================
Ticket ID: RIZ-451320
Department: Support netCDF Java
Priority: Normal
Status: Closed