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How to read in an input stream file that doesn't contain an 'xtime' variable (i.e., no time record)

mdtoy65

New member
I have a new stand-alone topographic netCDF data file that I would like to read in on initialization of 'atmosphere_model'. The file is a 1D (horizontal only) file and is for a new gravity wave drag parameterization. The model only runs if I include an 'xtime' variable in the netCDF file. Since the data is time-independent, it would be nice not to have to include this variable. If I don't include 'xtime', I get the following error message:

WARNING: File conus.ugwp_oro_data.nc does not contain a seekable xtime variable. Forcing a read of the first time record.
WARNING: Variable xtime not in input file.
ERROR: ********************************************************************************
ERROR: Error reading input stream ugwp_oro_data_in
CRITICAL ERROR: ********************************************************************************


The lines in the streams.atmosphere file dealing with the file are:

<immutable_stream name="ugwp_oro_data_in"
type="input"
filename_template="conus.ugwp_oro_data.nc"
input_interval="initial_only" />


Is there a way to prevent MPAS from needing a time record to exist in the file to read in the (time-irrelevant) data? Perhaps with a flag in streams.atmosphere?

Thank you.
 
Hi,
I wonder whether you have solved this issue? if so, please keep us updated about your progress.
The error message indicates that the missing of 'xtime' is just a warning message. I am suspicious it is not the critical issue that leads to the failure of MPAS run and something else might be wrong in the dataset itself.
if you still have the issue, please upload your streams.init_atmopshere for me to take a look. Please also clarify how you modify other codes including the Registry.
 
Hi Ming,
I uploaded 2 files: The core_atmosphere/Registry.xml file (this contains info on my 'ugwp_oro_data_in' stream) and the streams.atmopshere file. Let me know if you want me to send you the netCDF file that I'm trying to read. (As long as there's an 'xtime' variable it will read, but if it does not contain 'xtime', the model crashes.)

I agree that the warning message is not the issue, but for some reason it crashes in 'mpas_atm_core.F'.

Note that I added 'pdf' at the end of the file names to make them selectable with the 'Attach files' feature.

Thank you.
-- Mike
 

Attachments

  • Registry.xml.pdf
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  • streams.atmosphere.pdf
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Mike,

Thank you for uploading these files. Would you please also upload the following files:

namelist.atmopshere
x1.10242.init.nc
conus.ugwp_oro_data.nc (the previous link no longer works)

I will repeat your case and see whether we can find a solution to make it work.

It may take some time because our group will be on a business trip next week.

Ming
 
Ming,
I uploaded the files you requested, but again I had to add the 'pdf' suffix to make them 'attachable' in your app (they are grayed out and can't be selected otherwise).
There are two 'ugwp_oro_data' files, one with the 'xtime' variable and the other without it. The one without it causes the crash.
I was just notified that the x1.10242.init.nc file is too large for your server to process. You can access it via my Google Drive at:

Thanks,
Mike
 

Attachments

  • namelist.atmosphere.pdf
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  • x1.10242.ugwp_oro_data.nc.pdf
    807.7 KB · Views: 0
  • x1.10242.ugwp_oro_data.no_xtime.nc.pdf
    807.4 KB · Views: 1
Hi Mike,
I am terribly sorry to answer so late, --- we were on a business trip early October and have many stuff to catch up later.

I have talked to our software engineers about this issue. The basic idea whether to include 'xtime' in data is that, we want the initial/boundary/output files to contain 'xtime', while those time-invariant data like grid and static data files should not contain 'xtime'. Based on this idea, we prefer not to modify codes in core_atmosphere to process data that doesn't contain 'xtime'. Thereby, please add 'xtime' to the data file that will be read into MPAS for atmopshere_model run.

Please let me know if you have more concerns. Thanks.
 
Hi Ming,

That's okay. Thank you very much for getting back with me, and I understand why you would not want to modify the code. For now, I'll leave 'xtime' in the stream.

-- Mike
 
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