how to install WRF and WPS on Apple ARM64 system

[sunt05]

My major development platform is vscode on an Apple M1 Max - so it would be good for me to be able to run WRF and WPS locally on my laptop for more rapid testing.

The existing guideline (as of 18 Nov 2023) is less straightforward.
As such, here I document the steps to install WRF 4.5 on my laptop, which hopefully will also be useful to our further development ofWRF-SUEWS.

[sunt05]

WRF

Codebase

https://github.com/sunt05/WRF/tree/release-v4.5.2

Dependencies

I utilise a more recent GCC and homebrew-ed NetCDF libraries:

brew install [email protected] netcdf-c netcdf-fortran

Next, set the NETCDF environment variable:

export NETCDF=/opt/homebrew/

Compilation

The compilation process is rather straightforward: simply select either serial or sm for the gfortran+gcc toolchain - both options are functional.

Note

For earlier versions of WRF - tested WRF v4.0 for WRF-SUEWS - the issue lies in the old code convention that is not working well with the default gfortran flags; one needs to modify this line in configure.wrf to:

FCBASEOPTS      =       $(FCBASEOPTS_NO_G) $(FCDEBUG) -fallow-invalid-boz -fallow-argument-mismatch

[sunt05]

WPS

Codebase

https://github.com/wrf-model/WPS/tree/release-v4.5

Dependencies

This part proved a bit tricky - I initially thought it would be similar to the homebrew method, but that wasn't the case.

To resolve dependency issues, follow these steps:

• Issue 1: WPS build fails when WRF was compiled with an 'smpar' option wrf-model/WPS#110 - This will sort out any missing libraries due to sm compilation.

• Issue 2: Ungrib build fails when jasper version > 3. wrf-model/WPS#207 - This resolves deprecated Jasper functions used in WPS (run ./configure --build-grib2-libs).

Compilation

Once I've sorted out the above dependencies, compilation is straightforward.