Configuring the TOYCLIM coupled model using OASIS3

The TOYCLIM coupled model performs a coupling between an ``empty" ocean model, toyoce, an``empty" atmospheric model, toyatm, and an ``empty" atmospheric chemistry model, toyche. There is no real physics or dynamics within the models. However, the coupling fields have a realistic size, the operations performed within OASIS3 on the coupling fields are realistic, and the coupling using the PRISM System model interface (PSMILe) is also realistic. The TOYCLIM atmosphere and chemistry models have the same grid and the same parallel partitioning on 3 processes. There is no need of interpolation and the coupling fields are directly exchanged between these two models without going through OASIS3 interpolation process. More details on the TOYCLIM coupled model can be found in (6).

The TOYCLIM coupled model uses PRISM standard running environment (SRE). To run it, one has to go through the following steps:

1. Go to the directory prism/util/running/frames
2. Create the include files for your platform if they do not already exist in directory prism/util
   /running/frames/include_<node> where <node> is the name of the platform.
3. Run the script Create_TASKS.frm to generate a setup file for your TOYCLIM experiment:

   
   
   
   
   
   

   where <expid> is your experiment name.

4. To change the configuration of your experiment, modify the values of the configurable entries in the setup file prism/util/running/frames/setup/setup_toyclim_<expid>, which contains default values for these entries. Some of these configurable entries directly enter the OASIS3 configuration file namcouple, other affect the running script only. The namcouple file is created from the namcouple base file (see namcouple_toyclim in prism/util/running
   /adjunct_files/oasis3) by replacing the configurable entries (which begin with "#") by the value defined in the setup file. The namcouple will be read by OASIS3 at runtime. The variables that can be defined in the set-up file and correspond to configurable namcouple entries are the following:
   1. jobname: Experiment identifier; it is composed of three digits; (#Jobname).

   2. nlogprt: Integer controlling the amount of information written to the OASIS output file cplout. 0: minimum output, 1: medium output, 2: maximum output; (#Nlogprt).

   3. extrapwr: Flag to provoke the calculation of weights and addresses for nearest neighbour extrapolation (EXTRAP/NINENN) within OASIS3 (1) or to read them from file (0); (#Extrapwr).

   4. stat_fieldxx, where xx is the number of the field in the namcouple: The status of the xx coupling/IO field can be either `EXPOUT' or `EXPORTED', except for for which it is `INPUT', for for which it is `OUTPUT' and for and for which it is either `IGNOUT' or `IGNORED' (see section 5.3); (#Stat_fieldxx).

   5. dtFxx, where xx is the number of the field in the namcouple: The coupling or I/O period of the xx coupling/IO field, which must be a multiple of 14400, except for for which it must be a multiple of 43200, and for , and for which it must be a multiple of 3600; (#Dtxx).

   6. iniyear, inimonth and iniday: the initial date of the experiment, respectively as YYYY, MM and DD(#Inidate).

   7. message_passing: Message passing method, either MPI2 or MPI1 (for more details, see section 4.1); (in #Channel)

   8. bsend: either `yes' or `no', indicates whether the buffered MPI_BSend or the standard blocking send MPI_Send will be used to send the coupling fields (for more details, see section 5.2) (in #Channel)

   The variables that can be additionally defined in the setup file but do not correspond to any configurable namcouple entries are the following:

   1. ncplvers: the namcouple version. Put "" to use the namcouple base file completed with the values defined in the setup file. To use another namcouple, a particular value has to be given to ncplvers, and a namcouple named namcouple_toyclim_ncplvers has to be available in prism/util/running/adjunct_files/oasis3.

   2. gridswr: either `0' if you want the models to use the grid description files if they exist, or `1' if you want the models to unconditionally (re)generate those grid description files (for more details, see section 4.2).

5. Type `Create_TASKS.frm toyclim <expid>' a second time. The script will check the parameters you specified in setup_toyclim_<expid>. If a parameter is not supported or a combination of parameters does not make sense Create_TASKS.frm writes an error message and stops.
6. Correct the experimental setup file if necessary and run Create_TASKS.frm again until the setup check is passed successfully.

Once the setup is done, all appropriate files and the script to start the experiment are available in the directory home/expid, where home and expid are defined in the setup file.