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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