def scale_ssi(ds):
    """
    Scale SSI by converting to mW m-2 nm-1
    """
    ds['ssi'] = ds.ssi * 1000
    ds['ssi'].attrs['units'] = "mW m-2 nm-1"
    ds['ssi'].attrs['long_name'] = "NOAA Climate Data Record of Daily Solar Spectral Irradiance"
    return ds