Preparing your system

This section discusses:

  • Required system libraries for running WRF-GC.

  • Required common input data for running WRF-GC.

The steps in this page only need to be run once, and generally do not need to be re-done unless WRF-GC version updates.

Software requirements

You will need a Linux system with the following compilers, libraries, and tools:

  • Compiler: Intel (version 15 or above), or gfortran.

  • MPI Library: MVAPICH2 (version 2.3 or above), OpenMPI, or Intel MPI.

  • zlib, hdf5 (version 1.8 or above), netCDF-C (version 4.6.1 or above), netCDF-Fortran (version 4.4.4 or above), JasPer (version 1.900)

  • Git version management

If you already run GEOS-Chem, you may already have met the compiler and netCDF requirements.

Below are some specific guidance, but if you already know how to set up libraries, point WRF-GC to them in the environment configuration file, editing as necessary.

For the final environmental configuration file, see Environmental configuration file (for reference) for all the environmental variables that need to be defined.

Running on a cluster

Your system administrator may have installed these packages. For example, on the Harvard “Cannon” cluster, the following libraries are used:

module load git/2.17.0-fasrc01
module load intel/17.0.4-fasrc01
module load openmpi/2.1.0-fasrc02
module load netcdf/4.5.0-fasrc02
module load netcdf-fortran/4.4.4-fasrc06
module load jasper/1.900.1-fasrc02


Special note about the netCDF libraries. Since version 4, netCDF has been split into “netCDF-C” and “netCDF-Fortran”. Both of these are required for WRF-GC, and WRF expects them to be in the same folder. This is problematic in some clusters, as they may store netcdf and netcdf-fortran in different paths. The solution is to create your own paths, e.g., ~/wrf-gc/include, ~/wrf-gc/bin, and ~/wrf-gc/lib, and link the netCDF-C and netCDF-Fortran files into these folders respectively. e.g.,

Then see the environment configuration above to point WRF-GC to the libraries.

Running on AWS or with Spack

Some of the package setup from Haipeng’s guide on WRF-GC on AWS may be helpful.

Running on your own system

Compile libraries in the following order:

  • Install the compiler

  • Install MPI (e.g., MVAPICH2)

  • Install zlib

  • Install JasPer

  • Install HDF5

  • Install netCDF-C

  • Install netCDF-Fortran

When configuring these libraries, specify the install location somewhere, e.g.:

./configure --prefix=/home/example/wrf-gc

The general process to install libraries is to run configure, then make, then make install, then make check to make sure it is working.

Then see the environment configuration above to point WRF-GC to the libraries.

Data requirements

GEOS-Chem shared inputs (“ExtData”)


If someone on your cluster / system already runs GEOS-Chem, you may have the data already. If so, you may be able to skip all of the below steps.

Download the GEOS-Chem input data directories, specifically HEMCO and CHEM_INPUTS. For HEMCO they are very large, and you only need to download folders corresponding to the simulation year(s) you expect to run.

Refer to the GEOS-Chem User’s Guide: * Downloading data from WashU

WRF-GC needs ExtData/HEMCO/ and ExtData/CHEM_INPUTS/.

If you are running GEOS-Chem as well (e.g., for making WRF-GC boundary / initial conditions), you also need some meteorology fields, etc. Refer to the GEOS-Chem User’s Guide.

WRF Pre-Processor Geographical Data

Download the required geographical input data for WRF.

For high-resolution simulations, we recommend downloading “Download Highest Resolution of each Mandatory Field”. This takes approximately ~50 GB of disk space.

Environmental configuration file (for reference)

Below is an example environment file using the Intel compilers + OpenMPI. The following need to be edited to fit your system:

  • NETCDF needs to point to your netCDF install (inside this path there should be bin, lib, include for both NetCDF-C and NetCDF-Fortran)

  • JASPERLIB needs to point to your JasPer install’s lib folder

  • JASPERINC needs to point to your JasPer install’s include folder

  • NETCDF_HOME and NETCDF_FORTRAN_HOME point to NetCDF-C and NetCDF-Fortran. Can be the same as $NETCDF

If you are using the GNU compilers (gcc and gfortran), you also need to edit:

  • CC=gcc, CXX=gcc, FC=gfortran, ESMF_COMPILER=gfortran

If you are using other MPI libraries, you also need to edit:

  • ESMF_COMM to openmpi, mvapich2, or intelmpi.

  • If your system has weird, non-standard MPI installations, you may need to manually edit WRF-GC’s chem/Makefile.

export CC=icc
export OMPI_CC=$CC

export CXX=icpc
export OMPI_CXX=$CXX

export FC=ifort
export F77=$FC
export F90=$FC
export OMPI_FC=$FC
export ESMF_COMPILER=intel

# MPI Communication
export ESMF_COMM=openmpi

export NETCDF=/n/holyscratch01/jacob_lab/hplin/wrfgc

# WRF options
export WRF_EM_CORE=1
export WRF_NMM_CORE=0
export WRF_CHEM=1

# needed forwrfv4
export NETCDF_classic=1

# GC extras (only for GC not WRF-GC)
export OMP_STACKSIZE=1000000000

# Base paths
export GC_BIN="$NETCDF_HOME/bin"
export GC_INCLUDE="$NETCDF_HOME/include"
export GC_LIB="$NETCDF_HOME/lib"

# If using NetCDF after the C/Fortran split (4.3+), then you will need to
# specify the following additional environment variables