Merge pull request #1010 from PCMDI/bug/1009_lee1043_landmask

landmask generation for non-regular lat/lon grid

pcmdi_metrics/utils/create_land_sea_mask.py

@@ -7,14 +7,21 @@
 
 
 def create_land_sea_mask(
- obj: Union[xr.Dataset, xr.DataArray], as_boolean: bool = False
+ obj: Union[xr.Dataset, xr.DataArray],
+ lon_key: str = None,
+ lat_key: str = None,
+ as_boolean: bool = False,
 ) -> xr.DataArray:
  """Generate a land-sea mask (1 for land, 0 for sea) for a given xarray Dataset or DataArray.
 
  Parameters
  ----------
  obj : Union[xr.Dataset, xr.DataArray]
  The Dataset or DataArray object.
+ lon_key : str, optional
+ Name of DataArray for longitude, by default None
+ lat_key : str, optional
+ Name of DataArray for latitude, by default None
  as_boolean : bool, optional
  Set mask value to True (land) or False (ocean), by default False, thus 1 (land) and 0 (ocean).
 
@@ -41,14 +48,16 @@ def create_land_sea_mask(
  land_mask = regionmask.defined_regions.natural_earth_v5_0_0.land_110
 
  # Get the longitude and latitude from the xarray dataset
- key_lon = xc.axis.get_dim_keys(obj, axis="X")
- key_lat = xc.axis.get_dim_keys(obj, axis="Y")
+ if lon_key is None:
+ lon_key = xc.axis.get_dim_keys(obj, axis="X")
+ if lat_key is None:
+ lat_key = xc.axis.get_dim_keys(obj, axis="Y")
 
- lon = obj[key_lon]
- lat = obj[key_lat]
+ lon = obj[lon_key]
+ lat = obj[lat_key]
 
  # Mask the land-sea mask to match the dataset's coordinates
- land_sea_mask = land_mask.mask(lon, lat)
+ land_sea_mask = land_mask.mask(lon, lat=lat)
 
  if not as_boolean:
  # Convert the land-sea mask to a boolean mask