gfs_wave failing with GeocalculusError

[dnowacki-usgs]

I'm trying to retrieve gfs_wave output with Herbie. I'm following the example in the gallery. The rendered notebook in the gallery fails with

ECCODES ERROR   :  Polar stereographic Geoiterator: Only supported for spherical earth.
ECCODES ERROR   :  Geoiterator factory: Error instantiating iterator polar_stereographic (Problem with calculation of geographic attributes)
ECCODES ERROR   :  latitudes: Unable to create iterator

followed by a traceback ending with
GeocalculusError: Problem with calculation of geographic attributes

I'm encountering the same error on my local machine. This error raises no matter which product I specify for gfs_wave. Other models and model products seem to be working normally.

Herbie 2026.3.0, pandas 2.3.3, Python 3.14.5 on macOS.

[dnowacki-usgs]

I see this is actually a cfgrib error.

Opening the grib file directly using cfgrib produces the same error:
cfgrib.open_datasets('~/data/gfs_wave/20210711/gfswave.t00z.arctic.9km.f000.grib2')

cfgrib 0.9.15.1

I'm unfortunately not familiar enough with ECCODES and grib files to diagnose this further.

[williamhobbs]

Just a suggestion: you could try rolling back to an earlier version of eccodes if you have not already, e.g., pip install eccodes==2.45.0 (assuming you are using the latest 2.47.0). I've never seen this sort of issue, but I have seen eccodes updates break other things.

[dnowacki-usgs]

Thanks for the reply. I tried re-running with both eccodes 2.45 and 2.46 but both resulted in the same error.

I have a janky workaround using the command-line wgrib2 utility to write the downloaded grib2 files to netCDF. Then I can use xarray to read in those netCDF files, although much of the metadata and projection niceties get lost.