Created an umbrella issue for this
because it has come up several times in different contexts, but we never got around to it.

• Iris cannot read NetCDF4 strings stored in NetCDF variables #4101
• Cubes with string data won't save, or index #4412
• Error comparing cubes with string content. #5362
• Errors in netcdf save code relating to string data. #4502 (this one is a minor issue)

See also : pp-mo/ncdata#111

From what I've seen, the current situation is that "standard" CF-approved character-array variables ...

• don't read correctly, i.e. as character arrays with a string dimension), but instead as string (object) arrays
• ... and then don't save correctly, i.e. back to character arrays, but instead as variable-length netcdf "string" type
• ... which, of course, at present won't read back at all -- see Iris won't load netCDF files from the new CDS-beta #6149

( This has recently re-emerged in a query on ncdata
pp-mo/ncdata#111

From @znichollscr -- possibly not the same as @znicholls ???
)