Description of software

Used to compute means of forecast-minus-analysis, rms of forecast-minus-analysis and the standard deviation of the forecast for a particular date and time range from specified analysis and forecast files.

The output consists of three postcript files:

Note - on 09.02.2010 I changed the description of the output, but not the calculation.

Calculations are currently performed at a single time per cycle and any averages or summations use all 24 members of the model run.

Location of source code

The IDL source code can be found at /home/h05/frbr/idl_source_code/anfc_v4.pro

The code uses library routines written by Andy Heaps (NCAS, University of Reading) and these are accesssed by adding these two lines into your .profile file:

export IDL_PATH=+/usr/local/itt
.  /data/nwp1/frbr/TIDLWorkspace/andy_lib/guide4.sh

Method of use - interactive usage

The user must supply information as follows:

  1. A start and end cycle for the analysis.
  2. The year, month, day time for which the calculations will be done.
  3. A valid field code for the data under investigation; one of:
    • 03236 - 2m temperature
    • 04203 - dynamical rainfall rate (the default)
  4. The directory of the input forecast file.
  5. Substrings to create the forecast filename of the form FFFFFXXcccZZZmmYYY where FFFFF is the field code number, XXX may be of the form _ppn_qwq (the default), ccc is the cycle number, ZZZ may be of the form .oper (the default), mm is the member number (00 to 23), and YYY may be of the form .pp_001.nc (the default).
  6. The directory of the input analysis file.
  7. Substrings to create the analysis filename of the form : FFFFFXXXcccZZZ where FFFFF if the field code number XXX may be of the form _ppn_HLH120_20070726Q (the default), ccc is the cycle number, ZZZ may be of the form _STD_1km.pp0.nc (the default).

The dates and times specified above apply for the first cycle. For subsequent cycles the times and dates are incremented forward by one hour.

Method of use - batch mode

  1. The user should make a copy of the IDL source code in his/her working directory.
  2. Next, create a text file called anfc_controlfile in the working directory. This file should contain the following:
    111                                             ; start cycle
    130                                             ; end cycle
    2007              ; 4 digit start year
    07                ; 2 digit start month
    26                ; 2 digit start day
    1130              ; 4 digit start time
    03236             ; 5 digit field code
    /home/mm0200/apis/data/ETKF/20070726/plots/                 ; forecast file directory
    _qwq          ; XXX    - forecast filename FFFFFXXXcccZZZmmYYY
    .oper             : ZZZ    - FFFFF is the field code number, ccc is the
    .pp_001.nc        ; YYY    - cycle no., mm is the member number (00 to 23)
    /home/mm0200/apis/data/ETKF/20070726/plots/                 ; analysis file directory
    _qwq  ; AAA - analysis filename FFFFFAAAcccBBB
    .oper00.pp_001.nc        ; BBB - ccc is the cycle number
    

where the records should been changed to reflect the input data and output requirements of the user. The text to the right of the ';' symbols can be kept as a reminder of the meaning of the data records.

The idl code can now been run in a batch job or, if run interactively, will loop through the specified cycles.

Example output

The figures shows 1.5m temperature model results valid for a 1.5h forecast from 1000Z on 26 July 2007.

Note - 09.02.2010: RMS in the titles now reads 'MAE'. Also, the time-mean in the figures refers to the average over one cycle only!

Current code developments

None.