[ncl-talk] How to define date for WRF-chem to get average daily of a variable ?

[Dennis Shea]

I do not understand 'x' either

"I wonder about variable x; I did not define such a variable."

ncl 0> f = addfile(".....","r")  ; I do not have your file
ncl 1> print(f)                                             ; like ncdump
-h
ncl 2> Times = f->Times                            ; Times(Time,
DateStrLen)    (type character)
ncl 4> Time = wrf_times_c( Times, 0 )      ; "hours since" initial time on
file   (double); units recognized by cd_calendar
ncl 5> print(Time)

ncl 7> T = f->T
ncl 8> printVarSummary(T)

ncl 9> T&Time = Time                              ; associate time
coordinate
ncl 10> printVarSummary(T)

Variable: T
Type: float
Total Size: 19683000 bytes
            4920750 values
Number of Dimensions: 4
Dimensions and sizes: [Time | ??] x [bottom_top | 27] x [south_north | 81]
x [west_east | 90]
Coordinates:
            Time: [   0..  ?]
Number Of Attributes: 5
  FieldType : 104
  MemoryOrder : XYZ
  description : perturbation potential temperature (theta-t0)
  units : K
  stagger :
ncl 11> Tavg = calculate_daily_values (T, "avg", 0, True)
ncl 12> printVarSummary(Tavg)

Variable: Tavg
Type: float
Total Size: 1574640 bytes
            393660 values
Number of Dimensions: 4
Dimensions and sizes: [Time | ...] x [bottom_top | 27] x [south_north | 81]
x [west_east | 90]
Coordinates:
            Time: [   0..  12]
Number Of Attributes: 8
  _FillValue : 9.96921e+36
  FieldType : 104
  MemoryOrder : XYZ
  description : perturbation potential temperature (theta-t0)
  units : K
  stagger :
  Time :   0
  NCL_tag : calculate_daily_values

On Fri, Oct 7, 2022 at 5:16 AM Setareh Rahimi <setareh.rahimi at gmail.com>
wrote:

> Dear Dennis,
> So many thanks for your advice. I made corrections to my script as you
> suggested, and attempted to calculate and plot the average AOD for
> 2011-06-28 but I still get errors. I attached the script and the errors.
>
> As you can see from the error message, NCL says :fatal: No coordinate
> variable exists for dimension (Time) in variable (x)
> I wonder about variable x; I did not define such a variable.
>
> Please advise me on how to sort this issue out.
> Many thanks in advance,
> Best wishes,
>
> On Fri, Oct 7, 2022 at 6:02 AM Dennis Shea <shea at ucar.edu> wrote:
>
>> As noted in the documentation, *calculate_daily_values*
>> <https://www.ncl.ucar.edu/Document/Functions/Contributed/calculate_daily_values.shtml>
>> requires that the variable have a **time coordinate** that is recognized by
>> cd_calendar.
>>
>>   Times = f->Times                    ; Times(Time, DateStrLen)    (type character)
>>   Time = *wrf_times_c*( Times, 0 )      ; "hours since" initial time on file   (double); units recognized by cd_calendar
>>
>>      a2           = f->TAUAER   ; (Time, south_north, west_east)
>>      a2&Time = Time   ; associate the 'Time' coordinate with the variable
>> using  standard NCL & syntax
>>      printVarSummary(a2)
>>      print("------------------------------------")
>>
>>    a2Day = calculate_daily_values (a2, "avg", 0, opt)
>>    printVarSummary(a2Day)
>>    printMinMax (a2Day,1)
>>
>>
>>
>> On Wed, Oct 5, 2022 at 9:30 AM Setareh Rahimi via ncl-talk <
>> ncl-talk at mailman.ucar.edu> wrote:
>>
>>> Dear NCL users,
>>>
>>> I am trying to plot the daily average of AOD (aerosol optical depth)
>>> from WRF-chem outputs. However, I can not define the time so that NCL plots
>>> the daily average of AOD.(the script has been attached, and the model
>>> output is too large and I just used ncdump to show the header of some
>>> varibles ).
>>> I tried the following commands:
>>>
>>>
>>> times = wrf_user_getvar(f,"times",-1)
>>> printVarSummary(times)
>>> print(times)
>>> ymdh = cd_calendar(a2&times, -2)
>>>   print(ymdh)
>>>
>>> but faced an error.
>>> Would you please kindly advise me on how can I calculate the daily
>>> average of AOD from the hourly output of WRF-chem?
>>> Many thanks in advance,
>>> Best wishes,
>>> --
>>> 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
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mailman.ucar.edu/pipermail/ncl-talk/attachments/20221007/f99ecfc3/attachment.htm>