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

I think there was a intercommunication between sean and me. ill check on it.

John

> I just tried the released 4.3.22 version and still cannot read this
> grid.  The changes did not get put on the 4.3.22 release as promised.
> 
> Don
> 
> On 5/21/14 3:54 PM, Don Murray (NOAA Affiliate) wrote:
> > John-
> >
> > I've checked out and built the 4.3.22 branch, , but still cannot read
> > the files that have grid_latitude/grid_longitude as standard names in as
> > a grid in ToolsUI.
> >
> > I can read it in if I build the 4.5 branch.
> >
> > Don
> >
> > On 5/21/14 1:44 PM, Unidata netCDF Java Support wrote:
> >> 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
> >>
> >
> 
> --
> 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: Open