Error loading NSDIC-0116-nh data. CRS AXIS UNKNOWN (polar-grid)

[rbeucher]

🐛 Bug Report

I am trying to load the NSIDC-0116-nh raw data into a cube. Iris fails with the following error:
This is a CRS error from pyproj (v3.5.0).

CRSError: Invalid projection: PROJCS["NSIDC EASE-Grid North",GEOGCS["Unspecified datum based upon the International 1924 Authalic Sphere",DATUM["Not_specified_based_on_International_1924_Authalic_Sphere",SPHEROID["International 1924 Authalic Sphere",6371228,0,AUTHORITY["EPSG","7057"]],AUTHORITY["EPSG","6053"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.01745329251994328,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4053"]],UNIT["metre",1,AUTHORITY["EPSG","9001"]],PROJECTION["Lambert_Azimuthal_Equal_Area"],PARAMETER["latitude_of_center",90],PARAMETER["longitude_of_center",0],PARAMETER["false_easting",0],PARAMETER["false_northing",0],AUTHORITY["EPSG","3408"],AXIS["X",UNKNOWN],AXIS["Y",UNKNOWN]]: (Internal Proj Error: proj_create: unhandled axis direction: UNKNOWN)

Full Traceback:
traceback.txt

How To Reproduce

Steps to reproduce the behaviour:

1. Download data from https://nsidc.org/data/nsidc-0116/versions/4

import iris 
cubes = iris.load("icemotion_daily_nh_25km_19790101_19791231_v4.1.nc")

Expected behaviour

Should load data.

Screenshots

Environment

• Iris Version: 3.6.0

Additional context

This is used by the NSDIC cmoriser in ESMValTool

[valeriupredoi]

same for sh, for this:

• iris 3.4.1 and 3.6.0
• multiple pyproj including latest 3.6.0
• python 3,.10 and 3.11

Basically it's like this:

import iris

c = iris.load("/home/valeriu/Desktop/nsdic/Tier3/NSIDC-0116-sh/icemotion_daily_sh_25km_19840101_19841231_v4.1.nc")

spitting this out:

Traceback (most recent call last):
  File "/home/valeriu/iris_load_nsdic.py", line 3, in <module>
    c = iris.load("/home/valeriu/Desktop/nsdic/Tier3/NSIDC-0116-sh/icemotion_daily_sh_25km_19840101_19841231_v4.1.nc")
  File "/home/valeriu/miniconda3/envs/tool-latest2/lib/python3.10/site-packages/iris/__init__.py", line 319, in load
    return _load_collection(uris, constraints, callback).merged().cubes()
  File "/home/valeriu/miniconda3/envs/tool-latest2/lib/python3.10/site-packages/iris/__init__.py", line 285, in _load_collection
    result = _CubeFilterCollection.from_cubes(cubes, constraints)
  File "/home/valeriu/miniconda3/envs/tool-latest2/lib/python3.10/site-packages/iris/cube.py", line 105, in from_cubes
    for cube in cubes:
  File "/home/valeriu/miniconda3/envs/tool-latest2/lib/python3.10/site-packages/iris/__init__.py", line 270, in _generate_cubes
    for cube in iris.io.load_files(part_names, callback, constraints):
  File "/home/valeriu/miniconda3/envs/tool-latest2/lib/python3.10/site-packages/iris/io/__init__.py", line 223, in load_files
    for cube in handling_format_spec.handler(
  File "/home/valeriu/miniconda3/envs/tool-latest2/lib/python3.10/site-packages/iris/fileformats/netcdf/loader.py", line 566, in load_cubes
    cube = _load_cube(engine, cf, cf_var, filename)
  File "/home/valeriu/miniconda3/envs/tool-latest2/lib/python3.10/site-packages/iris/fileformats/netcdf/loader.py", line 276, in _load_cube
    engine.activate()
  File "/home/valeriu/miniconda3/envs/tool-latest2/lib/python3.10/site-packages/iris/fileformats/_nc_load_rules/engine.py", line 97, in activate
    run_actions(self)
  File "/home/valeriu/miniconda3/envs/tool-latest2/lib/python3.10/site-packages/iris/fileformats/_nc_load_rules/actions.py", line 528, in run_actions
    action_provides_grid_mapping(engine, grid_mapping_fact)
  File "/home/valeriu/miniconda3/envs/tool-latest2/lib/python3.10/site-packages/iris/fileformats/_nc_load_rules/actions.py", line 74, in inner
    rule_name = func(engine, *args, **kwargs)
  File "/home/valeriu/miniconda3/envs/tool-latest2/lib/python3.10/site-packages/iris/fileformats/_nc_load_rules/actions.py", line 172, in action_provides_grid_mapping
    coordinate_system = builder(engine, cf_var)
  File "/home/valeriu/miniconda3/envs/tool-latest2/lib/python3.10/site-packages/iris/fileformats/_nc_load_rules/helpers.py", line 719, in build_lambert_azimuthal_equal_area_coordinate_system
    ellipsoid = _get_ellipsoid(cf_grid_var)
  File "/home/valeriu/miniconda3/envs/tool-latest2/lib/python3.10/site-packages/iris/fileformats/_nc_load_rules/helpers.py", line 467, in _get_ellipsoid
    proj_crs = pyproj.crs.CRS.from_wkt(crs_wkt)
  File "/home/valeriu/miniconda3/envs/tool-latest2/lib/python3.10/site-packages/pyproj/crs/crs.py", line 431, in from_wkt
    raise CRSError(f"Invalid WKT string: {in_wkt_string}")
pyproj.exceptions.CRSError: Invalid WKT string:  PROJCS["NSIDC EASE-Grid South",GEOGCS["Unspecified datum based upon the International 1924 Authalic Sphere",DATUM["Not_specified_based_on_International_1924_Authalic_Sphere",SPHEROID["International 1924 Authalic Sphere",6371228,0,AUTHORITY["EPSG","7057"]],AUTHORITY["EPSG","6053"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.01745329251994328,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4053"]],UNIT["metre",1,AUTHORITY["EPSG","9001"]],PROJECTION["Lambert_Azimuthal_Equal_Area"],PARAMETER["latitude_of_center",-90],PARAMETER["longitude_of_center",0],PARAMETER["false_easting",0],PARAMETER["false_northing",0],AUTHORITY["EPSG","3409"],AXIS["X",UNKNOWN],AXIS["Y",UNKNOWN]]

I can provide the file, it's only 22MB in heft. Cheers guys 🍺

[remi-kazeroni]

I could also reproduce this with iris 3.4.1 and 3.6.0, used in recent ESMValTool installations. The dataset could be loaded successfully with iris 3.2.1 that we were using for ESMValTool v2.7

[rbeucher]

[like] Romain Beucher reacted to your message:

…

________________________________ From: Rémi Kazeroni ***@***.***> Sent: Wednesday, June 14, 2023 10:20:20 AM To: SciTools/iris ***@***.***> Cc: Romain Beucher ***@***.***>; Author ***@***.***> Subject: Re: [SciTools/iris] Error loading NSDIC-0116-nh data. CRS AXIS UNKNOWN (polar-grid) (Issue #5343) I could also reproduce this with iris 3.4.1 and 3.6.0, used in recent ESMValTool installations. The dataset could be loaded successfully with iris 3.2.1 that we were using for ESMValTool v2.7 — Reply to this email directly, view it on GitHub<#5343 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/AA4CVFUTG35OJTLOYZOLONDXLGF6JANCNFSM6AAAAAAZCTUDOE>. You are receiving this because you authored the thread.Message ID: ***@***.***>

[rbeucher]

Looks like a pyproj issue to me...

[trexfeathers]

@rbeucher just to let you know we have some scheduled time to investigate this later in the month.