make chunk size of lat and lon 1

Author: peterdudfield

src/nwp_consumer/internal/repositories/raw_repositories/ecmwf_realtime.py

@@ -282,6 +282,10 @@ def _convert(path: pathlib.Path) -> ResultE[list[xr.DataArray]]:
                     .sortby(variables=["step", "variable", "longitude"])
                     .sortby(variables="latitude", ascending=False)
                 )
+
+                # change lat and lon chunk size to 1
+                da = da.chunk({"latitude": 1, "longitude": 1})
+
             except Exception as e:
                 return Failure(ValueError(
                     f"Error processing dataset {i} from '{path}' to DataArray: {e}",