ensure WKT string is set; warn if BBOX not given

mllam · Jan 9, 2025 · ec75257 · ec75257
1 parent 7e5c79c
commit ec75257
Show file tree

Hide file tree

Showing 3 changed files with 79 additions and 15 deletions.
diff --git a/example.danra.yaml b/example.danra.yaml
@@ -47,21 +47,6 @@ inputs:
         dims: [x, y]
         attributes:
           crs_wkt: 'PROJCRS["DMI HARMONIE DANRA lambert projection", BASEGEOGCRS["DMI HARMONIE DANRA lambert CRS", DATUM["DMI HARMONIE DANRA lambert datum", ELLIPSOID["Sphere", 6367470, 0, LENGTHUNIT["metre", 1, ID["EPSG", 9001]]]], PRIMEM["Greenwich", 0, ANGLEUNIT["degree", 0.0174532925199433, ID["EPSG", 8901]]], ID["EPSG",4035]], CONVERSION["Lambert Conic Conformal (2SP)", METHOD["Lambert Conic Conformal (2SP)", ID["EPSG", 9802]], PARAMETER["Latitude of false origin", 56.7, ANGLEUNIT["degree", 0.0174532925199433, ID["EPSG", 8821]]], PARAMETER["Longitude of false origin", 25, ANGLEUNIT["degree", 0.0174532925199433, ID["EPSG", 8822]]], PARAMETER["Latitude of 1st standard parallel", 56.7, ANGLEUNIT["degree", 0.0174532925199433, ID["EPSG", 8823]]], PARAMETER["Latitude of 2nd standard parallel", 56.7, ANGLEUNIT["degree", 0.0174532925199433, ID["EPSG", 8824]]], PARAMETER["Easting at false origin", 0, LENGTHUNIT["metre", 1, ID["EPSG", 8826]]], PARAMETER["Northing at false origin", 0, LENGTHUNIT["metre", 1, ID["EPSG", 8827]]]], CS[Cartesian, 2], AXIS["(E)", east, ORDER[1], LENGTHUNIT["metre", 1, ID["EPSG", 9001]]], AXIS["(N)", north, ORDER[2], LENGTHUNIT["metre", 1, ID["EPSG", 9001]]], USAGE[AREA["Denmark and surrounding regions"], BBOX[47, -3, 65, 25], SCOPE["Danra reanalysis projection"]]]'
-          semi_major_axis: 6367470.0
-          semi_minor_axis: 6367470.0
-          inverse_flattening: 0.0
-          reference_ellipsoid_name: 'Sphere'
-          longitude_of_prime_meridian: 0.0
-          prime_meridian_name: 'Greenwich'
-          geographic_crs_name: 'DMI HARMONIE DANRA lambert CRS'
-          horizontal_datum_name: 'DMI HARMONIE DANRA lambert datum'
-          projected_crs_name: 'DMI HARMONIE DANRA lambert projection'
-          grid_mapping_name: 'lambert_conformal_conic'
-          standard_parallel: [0.0567, 0.0567]
-          latitude_of_projection_origin: 0.0567
-          longitude_of_central_meridian: 0.025
-          false_easting: 0.0
-          false_northing: 0.0
     dim_mapping:
       time:
         method: rename

diff --git a/mllam_data_prep/create_dataset.py b/mllam_data_prep/create_dataset.py
@@ -14,7 +14,9 @@
 from .ops.loading import load_and_subset_dataset
 from .ops.mapping import map_dims_and_variables
 from .ops.projection import (
+    ProjectionCompatibilityWarning,
     ProjectionInconsistencyWarning,
+    check_projection_compatibility,
     get_projection_crs,
     validate_projection_consistency,
 )
@@ -225,6 +227,12 @@ def create_dataset(config: Config):
         except ProjectionInconsistencyWarning as e:
             logger.warning(f"Projection information might be ambiguous: {e}")
         projection = pyproj.CRS.from_cf(projections[0])
+        try:
+            check_projection_compatibility(projection)
+        except ProjectionCompatibilityWarning:
+            logger.warning(
+                "WKT string should include a BBOX definition to be compatible with e.g. cartopy."
+            )
 
         # TODO: generalize the retrieval of x and y coords
         # coords = (dataarrays_by_target[target_output_var][0]['x'], dataarrays_by_target[target_output_var][0]['y'])

diff --git a/mllam_data_prep/ops/projection.py b/mllam_data_prep/ops/projection.py
@@ -11,6 +11,10 @@ class ProjectionInconsistencyWarning(Warning):
     pass
 
 
+class ProjectionCompatibilityWarning(Warning):
+    pass
+
+
 def _extract_grid_mapping_names(grid_mapping_attr: str) -> List[str]:
     """Extract grid mapping names from the grid_mapping attribute.
 
@@ -71,6 +75,73 @@ def _get_projection_mappings(dataset: xr.Dataset) -> Dict[str, Any]:
     return projections
 
 
+def check_projection_compatibility(proj: Dict[str, Union[str, dict]]) -> None:
+    """Check if the projection is compatible with mllam software.
+
+    Checks:
+    - if information is given as WKT string
+    - if the WKT string includes a BBOX definition
+
+    Parameters
+    ----------
+    proj : Dict[str, Union[str, dict]]
+        Projection information as a dictionary with the projection
+        variable names as keys and the projection attributes as values
+
+    Examples
+    --------
+    >>> proj1 = {"crs_wkt": "EPSG:4326"}
+    >>> check_projection_compatibility(proj1)
+    >>> crs_wkt = (
+    ...     'GEOGCRS["WGS 84",ENSEMBLE["World Geodetic System 1984 ensemble",'
+    ...     'MEMBER["World Geodetic System 1984 (Transit)"],'
+    ...     'MEMBER["World Geodetic System 1984 (G730)"],'
+    ...     'MEMBER["World Geodetic System 1984 (G873)"],'
+    ...     'MEMBER["World Geodetic System 1984 (G1150)"],'
+    ...     'MEMBER["World Geodetic System 1984 (G1674)"],'
+    ...     'MEMBER["World Geodetic System 1984 (G1762)"],'
+    ...     'MEMBER["World Geodetic System 1984 (G2139)"],'
+    ...     'MEMBER["World Geodetic System 1984 (G2296)"],'
+    ...     'ELLIPSOID["WGS 84",6378137,298.257223563,'
+    ...     'LENGTHUNIT["metre",1]],ENSEMBLEACCURACY[2.0]],'
+    ...     'PRIMEM["Greenwich",0,ANGLEUNIT["degree",0.0174532925199433]],'
+    ...     'CS[ellipsoidal,2],AXIS["geodetic latitude (Lat)",north,'
+    ...     'ORDER[1],ANGLEUNIT["degree",0.0174532925199433]],'
+    ...     'AXIS["geodetic longitude (Lon)",east,ORDER[2],'
+    ...     'ANGLEUNIT["degree",0.0174532925199433]],'
+    ...     'USAGE[SCOPE["Horizontal component of 3D system."],'
+    ...     'AREA["World."],],ID["EPSG",4326]]'
+    ... )
+    >>> proj2 = {"crs_wkt": crs_wkt}
+    >>> check_projection_compatibility(proj2)
+    Traceback (most recent call last):
+       ...
+    mllam_data_prep.ops.projection.ProjectionCompatibilityWarning: WKT string should include a BBOX definition to be compatible with e.g. cartopy.
+    >>> proj3 = {
+    ...     "semi_major_axis": 6367470.0,
+    ...     "semi_minor_axis": 6367470.0,
+    ...     "reference_ellipsoid_name": "Sphere",
+    ...     "grid_mapping_name": "lambert_conformal_conic",
+    ...     "standard_parallel": [0.0567, 0.0567],
+    ...     "latitude_of_projection_origin": 0.0567,
+    ...     "longitude_of_central_meridian": 0.025,
+    ...  }
+    >>> check_projection_compatibility(proj3)
+    Traceback (most recent call last):
+       ...
+    KeyError: 'Projection information must contain a WKT string.'
+    """
+    if "crs_wkt" not in proj:
+        raise KeyError("Projection information must contain a WKT string.")
+
+    if "BBOX" not in pyproj.CRS.from_cf(proj).to_wkt():
+        raise ProjectionCompatibilityWarning(
+            "WKT string should include a BBOX definition to be compatible with e.g. cartopy."
+        )
+
+    return
+
+
 def validate_projection_consistency(
     projections: List[Dict[str, Union[str, dict]]]
 ) -> None: