---------------------------------------------------------------------------
ProjError                                 Traceback (most recent call last)
Input In [169], in <module>
----> 1 tl_u, tl_v = rotate_winds(u, v, tl_cs)

File /lustre/dirac3/home/dc-serg1/mambaforge/envs/exo/lib/python3.10/site-packages/iris/analysis/cartography.py:1179, in rotate_winds(u_cube, v_cube, target_cs)
   1176 vt_cube.rename("transformed_{}".format(v_cube.name()))
   1178 # Get distance scalings for source crs.
-> 1179 ds_dx1, ds_dy1 = _crs_distance_differentials(src_crs, x, y)
   1181 # Get distance scalings for target crs.
   1182 x2, y2 = _transform_xy(src_crs, x, y, target_crs)

File /lustre/dirac3/home/dc-serg1/mambaforge/envs/exo/lib/python3.10/site-packages/iris/analysis/cartography.py:932, in _crs_distance_differentials(crs, x, y)
    930 crs_latlon = ccrs.Geodetic(globe=ccrs.Globe(ellipse="sphere"))
    931 # Transform points to true-latlon (just to get the true latitudes).
--> 932 _, true_lat = _transform_xy(crs, x, y, crs_latlon)
    933 # Get coordinate differentials w.r.t. true-latlon.
    934 dlon_dx, dlat_dx, dlon_dy, dlat_dy = _inter_crs_differentials(
    935     crs, x, y, crs_latlon
    936 )

File /lustre/dirac3/home/dc-serg1/mambaforge/envs/exo/lib/python3.10/site-packages/iris/analysis/cartography.py:854, in _transform_xy(crs_from, x, y, crs_to)
    838 def _transform_xy(crs_from, x, y, crs_to):
    839     """
    840     Shorthand function to transform 2d points between coordinate
    841     reference systems.
   (...)
    852 
    853     """
--> 854     pts = crs_to.transform_points(crs_from, x, y)
    855     return pts[..., 0], pts[..., 1]

File /lustre/dirac3/home/dc-serg1/mambaforge/envs/exo/lib/python3.10/site-packages/cartopy/crs.py:408, in CRS.transform_points(self, src_crs, x, y, z, trap)
    405     x[to_180] = (((x[to_180] + 180) % 360) - 180)
    406 try:
    407     result[:, 0], result[:, 1], result[:, 2] = \
--> 408         _safe_pj_transform(src_crs, self, x, y, z, trap=trap)
    409 except ProjError as err:
    410     msg = str(err).lower()

File /lustre/dirac3/home/dc-serg1/mambaforge/envs/exo/lib/python3.10/site-packages/cartopy/crs.py:50, in _safe_pj_transform(src_crs, tgt_crs, x, y, z, trap)
     49 def _safe_pj_transform(src_crs, tgt_crs, x, y, z=None, trap=True):
---> 50     transformer = _get_transformer_from_crs(src_crs, tgt_crs)
     51     transformed_coords = transformer.transform(x, y, z, errcheck=trap)
     52     if z is None:

File /lustre/dirac3/home/dc-serg1/mambaforge/envs/exo/lib/python3.10/site-packages/cartopy/crs.py:46, in _get_transformer_from_crs(src_crs, tgt_crs)
     44 @lru_cache()
     45 def _get_transformer_from_crs(src_crs, tgt_crs):
---> 46     return Transformer.from_crs(src_crs, tgt_crs, always_xy=True)

File /lustre/dirac3/home/dc-serg1/mambaforge/envs/exo/lib/python3.10/site-packages/pyproj/transformer.py:565, in Transformer.from_crs(crs_from, crs_to, skip_equivalent, always_xy, area_of_interest, authority, accuracy, allow_ballpark)
    558 if skip_equivalent:
    559     warnings.warn(
    560         "skip_equivalent is deprecated.",
    561         DeprecationWarning,
    562         stacklevel=2,
    563     )
--> 565 return Transformer(
    566     TransformerFromCRS(
    567         cstrencode(CRS.from_user_input(crs_from).srs),
    568         cstrencode(CRS.from_user_input(crs_to).srs),
    569         always_xy=always_xy,
    570         area_of_interest=area_of_interest,
    571         authority=authority,
    572         accuracy=accuracy if accuracy is None else str(accuracy),
    573         allow_ballpark=allow_ballpark,
    574     )
    575 )

File /lustre/dirac3/home/dc-serg1/mambaforge/envs/exo/lib/python3.10/site-packages/pyproj/transformer.py:310, in Transformer.__init__(self, transformer_maker)
    304     raise ProjError(
    305         "Transformer must be initialized using: "
    306         "'from_crs', 'from_pipeline', or 'from_proj'."
    307     )
    309 self._local = TransformerLocal()
--> 310 self._local.transformer = transformer_maker()
    311 self._transformer_maker = transformer_maker

File /lustre/dirac3/home/dc-serg1/mambaforge/envs/exo/lib/python3.10/site-packages/pyproj/transformer.py:97, in TransformerFromCRS.__call__(self)
     91 def __call__(self) -> _Transformer:
     92     """
     93     Returns
     94     -------
     95     _Transformer
     96     """
---> 97     return _Transformer.from_crs(
     98         self.crs_from,
     99         self.crs_to,
    100         always_xy=self.always_xy,
    101         area_of_interest=self.area_of_interest,
    102         authority=self.authority,
    103         accuracy=self.accuracy,
    104         allow_ballpark=self.allow_ballpark,
    105     )

File pyproj/_transformer.pyx:1001, in pyproj._transformer._Transformer.from_crs()

ProjError: Error creating Transformer from CRS.: (Internal Proj Error: proj_create_operations: Source and target ellipsoid do not belong to the same celestial body)