[ncl-talk] Save output as a NetCDF or tiff file

[Dennis Shea]

Read XLAT and XLONG from the source WRF file.

On Mon, Nov 13, 2023 at 11:43 PM Setareh Rahimi <setareh.rahimi at gmail.com>
wrote:

> Thank you for your help! but I still receive this error :
>
> fatal:Variable (XLAT) is undefined
>
> fatal:["Execute.c":8637]:Execute: Error occurred at or near line 186 in
> file aod
>
>
> fatal:Variable (XLONG) is undefined
>
> fatal:["Execute.c":8637]:Execute: Error occurred at or near line 187 in
> file aod
>
>
>
> On Tue, Nov 14, 2023 at 4:27 AM Dennis Shea <shea at ucar.edu> wrote:
>
>> By netCDF definition, a coordinate variable must be one-dimensional:
>>
>> The XLAT, XLONG variables are three dimensional.
>>
>> Time | 24] x [south_north | 229] x [west_east | 219]
>>
>> As with the WRF files, these must be written as regular variables.
>>
>>      ncdf->XLAT     = XLAT
>>      ncdf->XLONG = XLONG
>>
>> Most commonly, the XLAT/XLONG variables do not vary with time. Hence some
>> users just write the initial values as a two-dimensional variable
>>
>>      ncdf->XLAT     = XLAT(0,:,:)
>>      ncdf->XLONG = XLONG(0,:,:)
>>
>>
>>
>> On Mon, Nov 13, 2023 at 1:21 AM Setareh Rahimi <setareh.rahimi at gmail.com>
>> wrote:
>>
>>> Thanks Dennis, but the page is not available!
>>>
>>> On Mon, Nov 13, 2023 at 2:58 AM Dennis Shea <shea at ucar.edu> wrote:
>>>
>>>> See copy_VarCoords
>>>>
>>>> On Fri, Nov 10, 2023 at 1:39 PM Setareh Rahimi <
>>>> setareh.rahimi at gmail.com> wrote:
>>>>
>>>>> Thank you so much for your help. How can I assign lat/lon to the AOD,
>>>>> please?
>>>>> I used the below lines in the script but received the following error:
>>>>> " fatal:(XLAT) is not a named dimension in variable (a2)".
>>>>>
>>>>>
>>>>>
>>>>>        system("/bin/rm -f AOD550_2D.nc")    ; remove any pre-existing
>>>>> file
>>>>>
>>>>>        ncdf = addfile("AOD550_2D.nc" ,"c")  ; open output netCDF file
>>>>>
>>>>>
>>>>>
>>>>> ;===================================================================
>>>>>
>>>>>     ; create global attributes of the file (optional)
>>>>>
>>>>>
>>>>> ;===================================================================
>>>>>
>>>>>        fAtt               = True            ; assign file attributes
>>>>>
>>>>>        fAtt at title         = "Derived AOD"
>>>>>
>>>>>        fAtt at creation_date = systemfunc ("date")
>>>>>
>>>>>
>>>>>        fileattdef( ncdf, fAtt )            ; copy file attributes
>>>>>
>>>>>
>>>>>
>>>>> ;===================================================================
>>>>>
>>>>>     ; make time an UNLIMITED dimension; recommended  for most
>>>>> applications
>>>>>
>>>>>
>>>>> ;===================================================================
>>>>>
>>>>>        filedimdef(ncdf,"time",-1,True)
>>>>>
>>>>>
>>>>>
>>>>> ;===================================================================
>>>>>
>>>>>     ; output variables directly; NCL will call appropriate functions
>>>>>
>>>>>     ; to write the meta data associated with each variable
>>>>>
>>>>>
>>>>> ;===================================================================
>>>>>
>>>>>        ncdf->AOD550_2D  = AOD550_2D
>>>>>
>>>>>
>>>>>       ncdf->a2  = a2(0,:,:,:)
>>>>>
>>>>>       AOD550_2D!0    = "lat"
>>>>>
>>>>>       AOD550_2D!1    = "lon"
>>>>>
>>>>>              AOD550_2D&lat  = a2&XLAT
>>>>>
>>>>> ===========================================================================================
>>>>> here is printVarSummary of "a2"
>>>>>
>>>>> Variable: a2
>>>>>
>>>>> Type: float
>>>>>
>>>>> Total Size: 144434880 bytes
>>>>>
>>>>>             36108720 values
>>>>>
>>>>> Number of Dimensions: 4
>>>>>
>>>>> Dimensions and sizes: [Time | 24] x [bottom_top | 30] x [south_north
>>>>> | 229] x [west_east | 219]
>>>>>
>>>>> Coordinates:
>>>>>
>>>>>             Time: [   0..  23]
>>>>>
>>>>> Number Of Attributes: 6
>>>>>
>>>>>   coordinates : XLONG XLAT XTIME
>>>>>
>>>>>   stagger :
>>>>>
>>>>>   units : ?
>>>>>
>>>>>   description : bin 2 layer optical thickness
>>>>>
>>>>>   MemoryOrder : XYZ
>>>>>
>>>>>   FieldType : 104
>>>>>
>>>>>
>>>>>
>>>>> On Fri, Nov 10, 2023 at 8:17 PM Dennis Shea <shea at ucar.edu> wrote:
>>>>>
>>>>>> netCDF operator  'ncks' to extract a variable from a netCDF file and
>>>>>> copy it to another
>>>>>>
>>>>>> %> ncks -v xxx Model.nc XXX.nc
>>>>>>
>>>>>> where 'xxx' is the name of the variable on the model file
>>>>>> ===============================
>>>>>>     AOD
>>>>>>
>>>>>>        *system* <https://www.ncl.ucar.edu/Document/Functions/Built-in/system.shtml>("/bin/rm -f AOD.nc")    ; remove any pre-existing file
>>>>>>        ncdf = *addfile* <https://www.ncl.ucar.edu/Document/Functions/Built-in/addfile.shtml>("AOD.nc" ,"c")  ; open output netCDF file
>>>>>>
>>>>>>     ;===================================================================
>>>>>>     ; create global attributes of the file (optional)
>>>>>>     ;===================================================================
>>>>>>        fAtt               = True            ; assign file attributes
>>>>>>        fAtt at title         = "Derived AOD"
>>>>>>        fAtt at creation_date = *systemfunc* <https://www.ncl.ucar.edu/Document/Functions/Built-in/systemfunc.shtml> ("date")
>>>>>>        *fileattdef* <https://www.ncl.ucar.edu/Document/Functions/Built-in/fileattdef.shtml>( ncdf, fAtt )            ; copy file attributes
>>>>>>
>>>>>>     ;===================================================================
>>>>>>     ; make time an UNLIMITED dimension; recommended  for most applications
>>>>>>     ;===================================================================
>>>>>>        *filedimdef* <https://www.ncl.ucar.edu/Document/Functions/Built-in/filedimdef.shtml>(ncdf,"time",-1,True)
>>>>>>
>>>>>>     ;===================================================================
>>>>>>     ; output variables directly; NCL will call appropriate functions
>>>>>>     ; to write the meta data associated with each variable
>>>>>>     ;===================================================================
>>>>>>        ncdf->AOD  = AOD
>>>>>>
>>>>>> ================================
>>>>>> See
>>>>>> *https://www.ncl.ucar.edu/Applications/method_1.shtml
>>>>>> <https://www.ncl.ucar.edu/Applications/method_1.shtml>*
>>>>>>
>>>>>> On Fri, Nov 10, 2023 at 1:02 AM Setareh Rahimi via ncl-talk <
>>>>>> ncl-talk at mailman.ucar.edu> wrote:
>>>>>>
>>>>>>> Dear all,
>>>>>>> I have calculated Aerosol Optical Depth (AOD) from WRF-Chem output
>>>>>>> using "TAUAER2" and "TAUAER3" variables (script attached). Instead of using
>>>>>>> the created AOD to plot it, I would like to save the AOD as a NetCDF or
>>>>>>> tiff file. So how can I do this, please?
>>>>>>> I have another question. How can I extract one variable from the
>>>>>>> model output and save it as a NetCDF or tiff file?
>>>>>>> Please help me with these issues.
>>>>>>> Kind regards,
>>>>>>>
>>>>>>> --
>>>>>>> S.Rahimi
>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> ncl-talk mailing list
>>>>>>> ncl-talk at mailman.ucar.edu
>>>>>>> List instructions, subscriber options, unsubscribe:
>>>>>>> https://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>>>>>>
>>>>>>
>>>>>
>>>>> --
>>>>> S.Rahimi
>>>>>
>>>>>
>>>
>>> --
>>> S.Rahimi
>>>
>>>
>
> --
> S.Rahimi
>
>
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