First section of namcouple file

The first section of namcouple uses some predefined keywords prefixed by the $ sign to locate the related information. The $ sign must be in the second column. The first ten keywords are described hereafter:

• $SEQMODE: On the line below this keyword is the maximum number of fields that have to be, at one particular coupling timestep, necessarily exchanged sequentially in a given order. For $SEQMODE , the position of each coupling field in the sequence has to be given by its SEQ index (see below and also section 4.8).

• $CHANNEL: On the line below this keyword is the communication technique chosen. Choices are MPI1 or MPI2 for the CLIM communication technique and related PSMILe library, using MPI1 or MPI2 message passing. To run OASIS3 as an interpolator only, put NONE (see also section 6.1). The communication technique using Unix System V Shared Memory Segments, SIPC, is also supported. PIPE, or GMEM should still work but are not officially supported anymore and were not tested (corresponding sources can be retrieved from CERFACS CVS Server only).

  To use the CLIM/MPI2 communication technique, the lines below $CHANNEL are, e.g. for 3 models:

   
  $CHANNEL 
  MPI2 NOBSEND
  1    1  arg1 
  3    1  arg2
  3    1  arg3
  

  where MPI2 is the message passing used in CLIM and PSMILe, and NOBSEND indicates that standard blocking send MPI_Send should be used in place of the buffered MPI_BSend to send the coupling fields.

  If NOBSEND is not specified, the buffered send MPI_BSend will be used.

  The following lines (one line per model listed on the $NBMODEL line) indicate for each model the total number of processes, the number of processes implied in the coupling, and possibly launching arguments. Here the first model runs on one process which is of course implied in the coupling and the argument passed to the model is "arg1"; the second and third models run on 3 processes but only one process is implied in the coupling (i.e. exchanging information with OASIS3 main process), and the argument passed to the models are respectively ``arg2" and ``arg3''.

  To use the CLIM/MPI1 communication technique, the $CHANNEL lines are are as for MPI2 except that MPI2 is replaced by MPI1 and there is no launching arguments. gument.

  To use the SIPC communication technique, the user has to write only SIPC below the $CHANNEL keyword (corresponding sources can be retrieved from CERFACS CVS Server only).

• $NFIELDS: On the line below this keyword is the total number of fields exchanged and described in the second part of the namcouple.

• $JOBNAME: On the line below this keyword is a CHARACTER3 or CHARACTER4 variable giving an acronym for the given simulation.

• $NBMODEL: On the line below this keyword is the number of models running in the given experiment followed by CHARACTER6 variables giving their names. Then the user may indicate the maximum Fortran unit number used by the models. In the example, Fortran units above 55, 70, and 99 are free for respectively the ocean, atmosphere, and atmospheric chemistry models. If no maximum unit numbers are indicated, OASIS3 will suppose that units above 1024 are free. If $CHANNEL is NONE, $NBMODEL has to be 0 and there should be no model name and no unit number.

• $RUNTIME: On the line below this keyword is the total simulated time of the run, expressed in seconds. If $CHANNEL is NONE, $RUNTIME has to be the number of time occurrences of the field to interpolate from the restart file.

• $INIDATE: On the line below this keyword is the initial date of the run. The format is YYYYMMDD. This date is important only for the FILLING transformation and for printing information in OASIS3 log file cplout.

• $MODINFO: If coupling restart files are binary files (see section 7.3), the line below this keyword indicates if a header is encapsulated or not: it can be YES or NOT.

• $NLOGPRT: The line below this keyword refers to the amount of information that will be written to the OASIS3 log file cplout during the run. With 0, there is practically no output written to the cplout; with 1, only some general information on the run, the header of the main routines, and the names of the fields when treated appear in the cplout. Finally, with 2, the full output is generated.

• $CALTYPE: This new keyword gives the type of calendar used. For now, the calendar type is important only if FILLING analysis is used for a coupling field in the run and for printing information in OASIS3 log file cplout. Below this keyword, a number (0, 1 or n ) must be indicated by the user:
  • 0 : a 365 day calendar (no leap year)
  • 1 : a 365 or 366 (leap years) day calendar A year is a leap year if it can be divided by 4; however if it can be divided by 4 and 100, it is not a leap year; furthermore, if it can be divided by 4, 100 and 400, it is a leap year.
  • n : day month calendar.