Sentinel-2 L2A COG assets missing CRS metadata for specific scenes

[SashaNasonova]

Hello,

I encountered several Sentinel-2 L2A assets hosted by the Planetary Computer where the GeoTIFF opens successfully with rasterio, but ds.crs is None. This leads to issues down the line for a median calculation leading to the following exception: AttributeError: 'NoneType' object has no attribute 'to_epsg'. Here's the code snippet and full traceback:

data_all = stackstac.stack(
good_items,
assets= params['bands'] + ["SCL"],
bounds_latlon=bbox,
chunksize=1024, #512
resolution=params['scale'],
epsg=params['proj'],
properties=False)

scl = data_all.sel(band="SCL")
is_clear = scl.isin([2, 4, 5, 6, 7, 11])
rgb = data_all.sel(band=params['bands']).where(lambda x: x > 0, other=np.nan).where(is_clear).median(dim="time").compute()

Traceback (most recent call last):
File "C:\Dev\Python\mpc\mpc_s2_mosaic_parallel_wkill.py", line 203, in process_single_tile
rgb = data_all.sel(band=params['bands']).where(lambda x: x > 0, other=np.nan).where(is_clear).median(dim="time").compute()
File "C:\Users\snasonova\AppData\Local\miniforge3\envs\mpc2\Lib\site-packages\xarray\core\dataarray.py", line 1247, in compute
return new.load(**kwargs)
~~~~~~~~^^^^^^^^^^
File "C:\Users\snasonova\AppData\Local\miniforge3\envs\mpc2\Lib\site-packages\xarray\core\dataarray.py", line 1173, in load
ds = self._to_temp_dataset().load(**kwargs)
File "C:\Users\snasonova\AppData\Local\miniforge3\envs\mpc2\Lib\site-packages\xarray\core\dataset.py", line 569, in load
evaluated_data: tuple[np.ndarray[Any, Any], ...] = chunkmanager.compute(
~~~~~~~~~~~~~~~~~~~~^
*chunked_data.values(), **kwargs
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
)
^
File "C:\Users\snasonova\AppData\Local\miniforge3\envs\mpc2\Lib\site-packages\xarray\namedarray\daskmanager.py", line 85, in compute
return compute(*data, **kwargs) # type: ignore[no-untyped-call, no-any-return]
File "C:\Users\snasonova\AppData\Local\miniforge3\envs\mpc2\Lib\site-packages\dask\base.py", line 685, in compute
results = schedule(expr, keys, **kwargs)
File "C:\Users\snasonov\AppData\Local\miniforge3\envs\mpc2\Lib\site-packages\stackstac\to_dask.py", line 189, in fetch_raster_window
data = reader.read(current_window)
File "C:\Users\snasonova\AppData\Local\miniforge3\envs\mpc2\Lib\site-packages\stackstac\rio_reader.py", line 383, in read
reader = self.dataset
^^^^^^^^^^^^
File "C:\Users\snasonova\AppData\Local\miniforge3\envs\mpc2\Lib\site-packages\stackstac\rio_reader.py", line 379, in dataset
self._dataset = self._open()
~~~~~~~~~~^^
File "C:\Users\snasonova\AppData\Local\miniforge3\envs\mpc2\Lib\site-packages\stackstac\rio_reader.py", line 346, in _open
"crs": ds.crs.to_epsg(),
^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'to_epsg'

The problem scenes are over British Columbia, Canada:

['S2C_MSIL2A_20260406T185911_R013_T10UEA_20260407T003455',
'S2B_MSIL2A_20260404T190909_R056_T11VLG_20260404T231005',
'S2B_MSIL2A_20260406T194859_R085_T09UUU_20260406T233341',
'S2B_MSIL2A_20260406T194859_R085_T09UVT_20260406T233341']

Interestingly they are from April 4th and 6th and from both S2B and S2C.

I've built a workaround to check per scene crs information and remove the scenes that are causing the issue if the median calculation fails using rasterio.

Cheers,
Sasha