Variable Names

There is no single universal standard that mandates variable names in an xarray.Dataset or CF conventions. Therefore, the standard_name and vocabulary are critically important for interoperability.

CMIP6 Variable Mapping by Category

This table maps CF standard names to CMIP6 variable names, organized by category. These short names are typically used in CMIP6 NetCDF output and should be matched to your xarray variables via the standard_name attribute.

Temperature

CF Standard Name	CMIP6 Name	Description	MIP Table	Dimensions
sea_water_conservative_temperature sea_water_temperature sea_water_potential_temperature	thetao	Conservative temperature Sea water temperature Sea water potential temperature	Omon	(time, depth, lat, lon) (time, depth, lat, lon) (time, depth, lat, lon)

Salinity

CF Standard Name	CMIP6 Name	Description	MIP Table	Dimensions
sea_water_absolute_salinity sea_water_practical_salinity sea_water_salinity	so	Absolute salinity (g/kg) Practical salinity General salinity (deprecated)	Omon	(time, depth, lat, lon) (time, depth, lat, lon) (time, depth, lat, lon)

Pressure

CF Standard Name	CMIP6 Name	Description	MIP Table	Dimensions
sea_water_pressure sea_water_pressure_at_sea_floor	pso	Pressure Pressure at sea floor	Omon Omon	(time, depth, lat, lon) (time, depth, lat, lon)

Density

CF Standard Name	CMIP6 Name	Description	MIP Table	Dimensions
sea_water_sigma_theta sea_water_potential_density sea_water_neutral_density ocean_sigma_coordinate	sigma0 gamma_n —	Density anomaly to 1000, surface reference Same as sigma-theta Neutral density estimate Vertical coordinate metadata	Omon Omon Omon —	(time, depth, lat, lon) (time, depth, lat, lon) (time, depth, lat, lon) —

Velocity

CF Standard Name	CMIP6 Name	Description	MIP Table	Dimensions
baroclinic_northward_sea_water_velocity bartropic_northward_sea_water_velocity	votemper vbar	Baroclinic (layered) meridional velocity Depth-averaged (barotropic) meridional velocity	Omon Omon	(time, depth, lat, lon) (time, lat, lon)

Transport

CF Standard Name	CMIP6 Name	Description	MIP Table	Dimensions
northward_ocean_freshwater_transport northward_ocean_freshwater_transport_due_to_gyre northward_ocean_freshwater_transport_due_to_overturning northward_ocean_heat_tranpsport ocean_volume_transport_across_line ocean_meridional_overturning_mass_streamfunction ocean_meridional_overturning_streamfunction	fwt_north fwt_north_gyre fwt_north_ovt fht_north vol_transport moc mosf	Total freshwater transport Gyre component of freshwater transport Overturning component of freshwater transport Total northward heat transport Volume transport across a defined line or section Overturning streamfunction (mass) General overturning streamfunction	Omon Omon Omon Omon Omon Omon Omon	(time, depth, lat, lon) (time, depth, lat, lon) (time, depth, lat, lon) (time, depth, lat, lon) (time, depth, lat, lon) (time, depth, lat) (time, depth, lat)