Practical introduction to Hirlam

Kalle Eerola, 2002, updated 2005.

Where to find information

contains collected information:

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This does not contain every piece, what is in the miniSMS version

The miniSMS definition file is created  into $HL_DATA when
starting an experiment

1. Compile

2. Constant Files (ConstantFiles)

3. Prepare constant files depending depending on date (MakeCycleInput)

Repeat for every date

The next is repeated for every cycle


4. Define the background field (Fg)

5. Surface analysis (Span)

6. Input for upper level analysis

  • analysis error (VARinput)
  • 7. 3dvar analysis

  • perform the 3dvar analysis,   (VARan)
  • this is a parallel program
  • 8. Postprocessing of analysis (Postpp)

    9. Diagnostic file from the analysis

  • Contains information from the observation usage, analysis increments
  • Creates a separate file (CMAstat)
  • Forecast

    10. Define the input for the forecast model (FCinput)

    11. Run the forecast

    The next is repeated for every cycle


    12. Verification against observations

    13. Archiving of the results

    14. Cleaning of data directories


    Some important features

    1. Identify your experiment (EXP)

    2. Create a Hirlam environment for yourself

    3. Some important (pseudo)variables

    3.1 Specific for one platform, normally the user need not modify these and he has only read 
    and execution rights to these

    3.2 Specific for one user

    3.3 Specific for one experiment

    4. How this hierarchy is achieved

    5 How you define, modify and run an experiment

    Running Hirlam

    Needed preparations, when running Hirlam 5.1.2 on Metis for the first time

    Now you can run experiments:

    hir512 ZZZ

    Examples of a few typical Env_ files are in the directory Examples