PyNGL and PyNIO are not being developed anymore. See the information in this [newsletter](https://geocat.ucar.edu/blog/2020/11/11/November-2020-update). It's not possible to add them to the conda environment. PyNGL is replaced by GeoCAT. See issue #27 . GeoCAT [documentation](https://geocat-comp.readthedocs.io/en/latest/) and [examples](https://geocat-examples.readthedocs.io/en/latest/)