How to build community GSI/EnKF?

1. Hera, Jet, Orion, Cheyenne users:

For users on the following supercomputers Hera, Jet, Orion, Cheyenne, the build process is very straight forward:

git clone https://github.com/comgsi/GSI
cd GSI
ush/build.comgsi

The build.comgsi script will load required modules, set required environmental variables and build GSI, regional EnKF and other utilities. All executables are under the build/bin directory.

2. Community users:

With the transition of NOAA GSI/EnKF codes to Github, the original (outdated) libsrc/ was removed and those libraries will come from the NCEPLIBS repository released by UFS. For how to build NCEPLIBS, please seek helps from the UFS support forum.

Community users can follow these steps to build GSI/EnKF:

2.1. build bufrlib and wrfio lib

This extra step is required as NCEPLIBS does not release bufrlib and wrfio lib at this moment. In the future, when NCEPLIBS includes these two libraries, this step will not be needed.

You can build these two libraries from the comgsi/GSILIBS repo at Github as follows:

git clone https://github.com/comgsi/GSILIBS
cd GSILIBS
mkdir build; cd build
cmake -DBUILD_CORELIBS=ON ..
make -j8

The compiled libraries will be under the build/lib directory. You will need this path in step 2.3.3.

2.2 build NCEPLIBS

The UFS support forum provides helps on how to build NCEPLIBS. Please submit your questions there.

FYI, Here is a quick summary how we installed NCEPLIBS.

2.3. build GSI/EnKF

(1) Clone the comgsi/GSI repo:

git clone https://github.com/comgsi/GSI

(2) create a file to list all modules required by the build process:

for example, a file modulefile.me.GSI_UPP_WRF may looks like as follows:

module purge
module load intel/18.0.5 ncarenv ncarcompilers
module load impi/2018.4.274
module load mkl
module load netcdf
module load cmake/3.16.4

(3) change the following three variables in the ush/build.comgsi script based on your computing environment

modulefile="/my/modulefile.me.GSI_UPP_WRF"
NCEPLIBS="/my/NCEPLIBS/b_intel18.0.5_impi2018.4.274/install"
GSILIBS="/my/GSILIBS/b_intel18.0.5_impi2018.4.274/"

(4) run "ush/build.comgsi" from the main GSI directory

NOTE For those who don't have the environmental module system in your computing platform, you may follow the ush/build.comgsi script on how to set up environmental variables and then do the compiling.

2.4. fix files

You can get some basic fix files from the comgsi/fix repository:

git clone https://github.com/comgsi/fix

For a complete set of fix files, please download them from the DTC website.

If you have any questions, please contact gsi-help@ucar.edu.