let function takes lon and lat key for data array name in case not st…

…andard

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