Code Sample, a copy-pastable example if possible

python path = '/work/Julius.Busecke/CM2.6_staged/CM2.6_A_V03_1PctTo2X/annual_averages' ds_ocean = xr.open_mfdataset(os.path.join(path,'ocean.*.ann.nc'), chunks={'time':1}, decode_times=False, engine='scipy') ds_ocean gives

```

ValueError Traceback (most recent call last) <ipython-input-7-278556ff881c> in <module>() 1 path = '/work/Julius.Busecke/CM2.6_staged/CM2.6_A_V03_1PctTo2X/annual_averages' ----> 2 ds_ocean = xr.open_mfdataset(os.path.join(path,'ocean.*.ann.nc'), chunks={'time':1}, decode_times=False, engine='scipy') 3 ds_ocean

~/code/miniconda/envs/standard/lib/python3.6/site-packages/xarray/backends/api.py in open_mfdataset(paths, chunks, concat_dim, compat, preprocess, engine, lock, kwargs) 503 lock = _default_lock(paths[0], engine) 504 datasets = [open_dataset(p, engine=engine, chunks=chunks or {}, lock=lock, --> 505 kwargs) for p in paths] 506 file_objs = [ds._file_obj for ds in datasets] 507

~/code/miniconda/envs/standard/lib/python3.6/site-packages/xarray/backends/api.py in <listcomp>(.0) 503 lock = _default_lock(paths[0], engine) 504 datasets = [open_dataset(p, engine=engine, chunks=chunks or {}, lock=lock, --> 505 **kwargs) for p in paths] 506 file_objs = [ds._file_obj for ds in datasets] 507

~/code/miniconda/envs/standard/lib/python3.6/site-packages/xarray/backends/api.py in open_dataset(filename_or_obj, group, decode_cf, mask_and_scale, decode_times, autoclose, concat_characters, decode_coords, engine, chunks, lock, cache, drop_variables) 283 elif engine == 'scipy': 284 store = backends.ScipyDataStore(filename_or_obj, --> 285 autoclose=autoclose) 286 elif engine == 'pydap': 287 store = backends.PydapDataStore(filename_or_obj)

~/code/miniconda/envs/standard/lib/python3.6/site-packages/xarray/backends/scipy_.py in init(self, filename_or_obj, mode, format, group, writer, mmap, autoclose) 133 filename=filename_or_obj, 134 mode=mode, mmap=mmap, version=version) --> 135 self.ds = opener() 136 self._autoclose = autoclose 137 self._isopen = True

~/code/miniconda/envs/standard/lib/python3.6/site-packages/xarray/backends/scipy_.py in _open_scipy_netcdf(filename, mode, mmap, version) 81 try: 82 return scipy.io.netcdf_file(filename, mode=mode, mmap=mmap, ---> 83 version=version) 84 except TypeError as e: # netcdf3 message is obscure in this case 85 errmsg = e.args[0]

~/code/miniconda/envs/standard/lib/python3.6/site-packages/scipy/io/netcdf.py in init(self, filename, mode, mmap, version, maskandscale) 264 265 if mode in 'ra': --> 266 self._read() 267 268 def setattr(self, attr, value):

~/code/miniconda/envs/standard/lib/python3.6/site-packages/scipy/io/netcdf.py in _read(self) 591 self._read_dim_array() 592 self._read_gatt_array() --> 593 self._read_var_array() 594 595 def _read_numrecs(self):

~/code/miniconda/envs/standard/lib/python3.6/site-packages/scipy/io/netcdf.py in _read_var_array(self) 696 # Build rec array. 697 if self.use_mmap: --> 698 rec_array = self._mm_buf[begin:begin+self._recs*self._recsize].view(dtype=dtypes) 699 rec_array.shape = (self._recs,) 700 else:

ValueError: new type not compatible with array. ```

xarray version: '0.9.6'

Problem description

I am trying to lazily read in a large number of high resolution ocean model output files. If I omit the engine='scipy' it works but takes forever. Is there a known reason why this would fail with the 'scipy' option?

I found #1313, and checked my conda environment: ``` $ conda list hdf

packages in environment at /home/Julius.Busecke/code/miniconda/envs/standard:

hdf4 4.2.12 0 conda-forge hdf5 1.8.18 1 conda-forge $ conda list netcdf

packages in environment at /home/Julius.Busecke/code/miniconda/envs/standard:

h5netcdf 0.4.2 py_0 conda-forge libnetcdf 4.4.1.1 6 conda-forge netcdf4 1.3.0 py36_0 conda-forge `` I can alsoimport netCDF4` and also load a single file using netCDF, so I am unsure if this is the same error as in #1313

I keep getting this error with some of the files for this particular model but not with others.

Any help would be greatly appreciated.