wrf-skill

"What do I need?"
|
+-- First time. What is WRF, how do I install it?
|   -> reference/getting-started.md
|      (clone, prereqs NetCDF/HDF5/MPI/Jasper/zlib/libpng, ./configure, ./compile em_real)
|
+-- I want to understand the source layout and the Registry
|   -> reference/architecture.md
|      (arch/, dyn_em, frame, phys, chem, hydro, share, external, main, run, Registry)
|
+-- I want to know how the ARW dynamical core works
|   -> reference/dynamic-cores-and-em.md
|      (ARW vs NMM, RK3 time-split, hybrid sigma-pressure coordinate, &dynamics namelist)
|
+-- I want to pick physics options for a real-data run
|   -> reference/physics-options.md
|      (microphysics, cumulus, PBL, radiation, surface layer, land surface)
|
+-- I want to run WRF with chemistry / aerosols
|   -> reference/wrf-chem.md
|      (chem/ subdirectory, MOZART/CBMZ/RADM2, anthropogenic + biogenic emissions)
|
+-- I want to run a real-data forecast with WPS
|   -> reference/running-real-case.md
|      (geogrid -> ungrib -> metgrid -> real.exe -> wrf.exe, namelist.wps + namelist.input)
|
+-- I want to run an idealized case (b_wave, quarter_ss, LES, ...)
|   -> reference/running-idealized.md
|      (ideal.exe, the em_* test cases, no WPS)
|
+-- I want to couple with WRF-Hydro / NWM
|   -> reference/wrf-hydro-coupling.md
|      (WRF_HYDRO=1 build, hydro.namelist, channel + terrain routing)
|
+-- The build / run is failing
|   -> reference/debugging.md
|      (configure / compile failures, segfaults in physics, CFL violations, nesting, restart)
|
+-- I want to submit a pull request to wrf-model/WRF
    -> reference/contributing-pr.md
       (NCAR fork model, JIRA, regression tests, code review)

WRF/
|-- arch/              <- per-platform configure stanzas + postamble
|-- chem/              <- WRF-Chem: gas chemistry, aerosols, emissions (200+ files)
|-- cmake/             <- CMake build system (alternative to ./configure)
|-- compile            <- top-level build script (wraps make)
|-- configure          <- top-level configure script (wraps arch/Config.pl)
|-- doc/               <- README files (README.namelist, README.io_config, ...)
|-- dyn_em/            <- ARW Eulerian Mass core (~40 files: solve_em.F, RK3, advection)
|-- external/          <- I/O bindings: netCDF, pnetCDF, HDF5, GRIB, ESMF, RSL_LITE, ...
|-- frame/             <- driver layer: domain manager, nesting, decomposition (~64 files)
|-- hydro/             <- WRF-Hydro coupling library
|-- inc/               <- generated header files (filled by Registry at build time)
|-- main/              <- top-level mains: wrf.F, real_em.F, ideal_em.F, ndown_em.F, tc_em.F
|-- phys/              <- physics suite (~235 files: module_mp_*, module_cu_*, module_bl_*, ...)
|-- Registry/          <- declarative registry (~40 files) that drives code generation
|-- run/               <- run directory: namelist.input, parameter tables, lookup tables
|-- share/             <- I/O helpers, output streams, mediation (~64 files)
|-- test/              <- per-case test directories (em_real, em_b_wave, em_les, ...)
|-- tools/             <- registry compiler, code-gen utilities
|-- var/               <- WRFDA (variational data assimilation)
|-- wrftladj/          <- WRFPLUS (tangent linear / adjoint)
|-- LICENSE.txt        <- WRF public-domain notice
|-- README             <- top-level README (release notes per version)
+-- README.md          <- short pointer to users' site

# 1. Get the code
git clone https://github.com/wrf-model/WRF.git
cd WRF

# 2. Set library environment (adjust to your install)
export NETCDF=/usr/local/netcdf
export HDF5=/usr/local/hdf5
export PATH=$NETCDF/bin:$PATH

# 3. Configure (interactive). For local laptop pick:
#      gfortran serial    -> option 32 on most platforms
#    For HPC pick:
#      INTEL dmpar        (distributed-memory MPI)
./configure
# inspect configure.wrf, especially DM_FC, NETCDFPATH, HDF5_PATH

# 4. Compile a real-data case (15-45 min single-threaded)
./compile em_real >& compile.log
grep -i "Error" compile.log    # should be empty
ls main/wrf.exe main/real.exe  # both must exist

# 5. Get WPS, build it, generate met_em files
git clone https://github.com/wrf-model/WPS.git
cd WPS
./configure   # pick GRIB2 (Jasper) option matching your WRF compiler
./compile >& compile.log
# (set namelist.wps, link Vtable, run geogrid.exe / ungrib.exe / metgrid.exe)

# 6. Run real.exe then wrf.exe
cd ../WRF/test/em_real
ln -sf ../../WPS/met_em.d01.* .
./real.exe              # produces wrfinput_d01 + wrfbdy_d01
./wrf.exe               # produces wrfout_d01_<date>

# 7. Inspect output
ncdump -h wrfout_d01_2024-01-01_00:00:00 | less
ncview wrfout_d01_2024-01-01_00:00:00