Extract the OpenIFS package

Create your local installation of OpenIFS 48R1.0 by cloning or branching from the git repository with the OpenIFS package. The location will be your new OIFS_HOME place.

You will need approximately 4 GB of disk space for the model sources, the bundle packages, and the built model binaries.

git clone ssh://git@git.ecmwf.int/~daha/openifs-main-git.git

Please note that currently access to this repository is restricted to a limited number of users.

Build OpenIFS

The $OIFS_HOME/bin/openifs-test.sh script can be used to build the model and run initial tests.

Edit the script and in line 16 set the location of your $OIFS_HOME directory which is the location where you have extracted the git repository and where this script should be located.
The usage of the script is shown with the command: openifs-test.sh -h
The option -e defines the compiler environment (intel or gnu). The default is intel.

Run the build process and the tests using the following command:

cd $OIFS_HOME
./bin/openifs-test.sh -cbt

Note: It is normal to see warnings during the build process.

This will build the model binaries for the selected compiler and will run the ifs-test t21 and t42 tests.

Set up the platform configuration file

You will need to set up a configuration file for your OpenIFS installation.

This file can be located anywhere but the recommended location would be somewhere inside your $OIFS_HOME installation.
This file sets global variables for your model installation, depending on your local system, and it will need to be "sourced" prior to running the model.
We provide a template for this configuration file in $OIFS_HOME/bin/oifs48r1-config.sh. You should edit this file and update variable OIFS_HOME with your installation's path.

We recommend that you include the following command in your shell configuration file (e.g. .bashrc):

source /path/to/configfile/oifs48r1-config.sh

This command should also be include in any batch job scripts that are intended to run OpenIFS.

Set up a forecast experiment

Extract the example forecast experiment i4xc.tgz into a location suitable for model experiments.

Note: The experiment directory would ideally be in a different location from the earlier model installation path $OIFS_HOME. In general, you will need more disk space for experiments, depending on the model grid resolution, the duration of the forecast experiment and the output fequency of model results.

Example:
On the ECMWF hpc2020 our model installation $OIFS_HOME will be in $HOME/openifs and for the experiment we extract the i4xc package in $PERM. The experiment directory shall therefore be $PERM/i4xc/2016092500.

Ensure the namelist files for the atmospheric model (fort.4) and for the wave model (wam_namelist) are found in the experiment directory.

You will need to copy two further scripts from the OpenIFS package into your experiment directory:

oifs-run: this is a generic run script which executes the binary model program file.
config.h: this is configuration file that determines settings for your experiment. It will be read by oifs-run.

Copy both files from $OIFS_HOME/bin into your experiment directory.

cp i4xc.tgz $PERM
cd $PERM
tar -xvzf i4xc.tgz
cd ./i4xc/2016092500
cp $OIFS_HOME/bin/oifs-run .
cp $OIFS_HOME/bin/config.h .