pvtend.compute_helmholtz_climatology

pvtend.compute_helmholtz_climatology(clim_dir: str | Path, output_dir: str | Path, lat: ndarray, lon: ndarray, *, clim_stem: str = 'era5_hourly_clim_1990-2020', engine: str = 'netcdf4') → list[Path][source]

Pre-compute Helmholtz decomposition of the climatological wind.

For each of the 12 months, loads the hourly climatological (u_bar, v_bar) fields, applies helmholtz_decomposition at every (hour, level) slice, and writes two NetCDF files per month containing u_rot_bar/u_div_bar and v_rot_bar/v_div_bar.

Parameters:

  • clim_dir – Directory containing per-variable-per-month climatology NetCDF files (e.g. era5_hourly_clim_1990-2020_jan_u.nc).

  • output_dir – Where to write the 24 Helmholtz climatology files.

  • lat – Latitude array [degrees], matching the climatology grid.

  • lon – Longitude array [degrees], matching the climatology grid.

  • clim_stem – Filename stem for the climatology files.

  • engine – NetCDF engine.

Returns:

List of 24 output file paths.