WRF

Licensing and Access

WRF is public domain software.

Running

The current version of WRF on Archer is 3.7.1, with all the patches applied. Two configurations have been built for use on Archer: one with dynamics only and one with chemistry.

Versions 3.5.1 and 3.6.1 are still available.

Dynamics only

The ARW model is provided (em_real) with basic nesting and distributed memory (MPI) + shared memory (OpenMP) parallelism. WPS has been built with GRIB2 support, and with distributed memory parallelism. Both packages have been compiled with the Cray compiler, and will run on the compute nodes only. Access this configuration with

module load wrf-wrf_wps_chem/3.7.1_build1-em_real-basic_nesting-dm+sm-cray-s

Run all of the WPS and WRF executables with aprun, e.g.

aprun -n 8 geogrid.exe
aprun -n 1 ungrib.exe
aprun -n 8 metgrid.exe
aprun -n 8 real.exe
aprun -n 24 wrf.exe

and set the OMP_NUM_THREADS variable to 1 if you are not wanting to use multiple OpenMP threads. You should experiment with combinations of OMP_NUM_THREADS and the aprun -n, -N and -d options to find an optimum for your particular simulation. ungrib.exe is serial, and requires

aprun -n 1 ungrib.exe

Once the module is loaded, the packages are in

$WRF_WRF_WPS_CHEM_DIR/WRFV3
$WRF_WRF_WPS_CHEM_DIR/WPS

with the executables in

$WRF_WRF_WPS_CHEM_DIR/WRFV3/run
$WRF_WRF_WPS_CHEM_CHEM_DIR/WPS

You may have scripts that are written to run in the WRFV3 directory, and use relative pathnames (e.g. ../WPS/geogrid.exe). These scripts will need to be modified to use the variable $WRF_WRF_WPS_CHEM_DIR.

Chemistry

The ARW model is provided (em_real), as for the dynamics only configuration, with WRF-Chem (currently without KPP), basic nesting, and distributed memory (MPI) parallelism. WPS has been built with GRIB2 support, and with distributed memory parallelism. Both packages have been compiled with the Cray compiler, and will run on the compute nodes only. Access this configuration with

module load wrf-wrf_wps_chem/3.7.1_build1-em_real-chem-basic_nesting-dm-cray-s

Access the packages and executables using the same environment variables as in the dynamics only case.

Geographical data

The geographical data is in $WRF_GEOG. Note that this data has the updated Iceland land use files. The old Iceland files are no longer provided on Archer since version 3.6.1. If you require these for version 3.6.1 and onwards, please contact the helpdesk.

Utilities

Only one WRF utility has been provided, wrfout_to_cf.ncl, in $WRF_WRF_WPS_CHEM_DIR/util.

Compiling