Summary
The obs4MIPs ERA-5 surface-temperature reference used by the PMP annual-cycle diagnostic carries a grid facet that disagrees with the resolution encoded in its own filename. The catalog entry advertises three different resolution signals for the same file:
filename: ts_mon_ERA-5_PCMDI_gr_198101-200412_AC_v20250224_2.5x2.5.nc (suggests 2.5x2.5)grid: 1.5x1.5 degree latitude x longitude (says 1.5x1.5)nominal_resolution: 100 km and instance_id: obs4MIPs.obs4MIPs.ECMWF.ERA-5.mon.ts.100km.gn.v20250224 (say ~100 km / ~1 degree)
Locations
packages/climate-ref-pmp/tests/test-data/annual-cycle/cmip6-ts/catalog.yamlpackages/climate-ref-pmp/tests/test-data/annual-cycle/cmip7-ts/catalog.yaml
Both reference the same ERA-5 annual-cycle file, so both share the discrepancy.
Likely cause
The grid / nominal_resolution facets are most likely populated from the obs4MIPs source netCDF global attributes (describing the native product), while the _2.5x2.5 filename suffix reflects a PMP regrid step applied for the annual-cycle comparison. If so, the facet describes the source grid while the file on disk is the regridded one.
Why it matters
grid and nominal_resolution are user-facing dataset facets. When they disagree with the file they describe, downstream consumers (and reviewers) can be misled about what was actually evaluated. Impact on the regression baselines themselves is low — the catalog is recorded input provenance, not a compared artefact — so this is metadata-correctness rather than a test failure.
Suggested investigation
- Confirm how REF derives the
grid / nominal_resolution facets during obs4MIPs ingest (source attributes vs on-disk grid).
- Decide whether
grid should reflect the actual (regridded) grid of the file, or whether the regridded reference should not carry the source product's grid metadata at all.
- Apply the fix at ingest so it propagates to all obs4MIPs references, not just these two fixtures.
Surfaced by CodeRabbit on #756 (catalog.yaml:19).
Summary
The obs4MIPs ERA-5 surface-temperature reference used by the PMP annual-cycle diagnostic carries a
gridfacet that disagrees with the resolution encoded in its own filename. The catalog entry advertises three different resolution signals for the same file:filename: ts_mon_ERA-5_PCMDI_gr_198101-200412_AC_v20250224_2.5x2.5.nc(suggests 2.5x2.5)grid: 1.5x1.5 degree latitude x longitude(says 1.5x1.5)nominal_resolution: 100 kmandinstance_id: obs4MIPs.obs4MIPs.ECMWF.ERA-5.mon.ts.100km.gn.v20250224(say ~100 km / ~1 degree)Locations
packages/climate-ref-pmp/tests/test-data/annual-cycle/cmip6-ts/catalog.yamlpackages/climate-ref-pmp/tests/test-data/annual-cycle/cmip7-ts/catalog.yamlBoth reference the same ERA-5 annual-cycle file, so both share the discrepancy.
Likely cause
The
grid/nominal_resolutionfacets are most likely populated from the obs4MIPs source netCDF global attributes (describing the native product), while the_2.5x2.5filename suffix reflects a PMP regrid step applied for the annual-cycle comparison. If so, the facet describes the source grid while the file on disk is the regridded one.Why it matters
gridandnominal_resolutionare user-facing dataset facets. When they disagree with the file they describe, downstream consumers (and reviewers) can be misled about what was actually evaluated. Impact on the regression baselines themselves is low — the catalog is recorded input provenance, not a compared artefact — so this is metadata-correctness rather than a test failure.Suggested investigation
grid/nominal_resolutionfacets during obs4MIPs ingest (source attributes vs on-disk grid).gridshould reflect the actual (regridded) grid of the file, or whether the regridded reference should not carry the source product's grid metadata at all.Surfaced by CodeRabbit on #756 (catalog.yaml:19).