air_virtual_potential_temperature

under discussion

Created: 10 Jan 2024

Proposer: Simon Peatman

Proposed Date: 2022-12-09

#32

Standard names: Virtual potential temperature

Change Date: 10 Jan 2024, 1:52 p.m.

virtual_potential_temperature_of_air K [UPKA]
The virtual potential temperature of air is the potential temperature at which the dry air constituent of a parcel of moist air would have the same density as the moist air at the same pressure.

Change Date: 1 Aug 2024, 12:11 p.m.

Change Date: 1 Aug 2024, 12:18 p.m.

air_virtual_potential_temperature K [UPKA]
The virtual potential temperature of air is the potential temperature at which the dry air constituent of a parcel of moist air would have the same density as the moist air at the same pressure. It is strongly recommended that a variable with this standard name should have a units_metadata attribute, with one of the values "on-scale" or "difference", whichever is appropriate for the data, because it is essential to know whether the temperature is on-scale (meaning relative to the origin of the scale indicated by the units) or refers to temperature differences (implying that the origin of the temperature scale is irrevelant), in order to convert the units correctly (cf. https://cfconventions.org/cf-conventions/cf-conventions.html#temperature-units).

Change Date: 11 Jun 2025, 4:44 p.m.

air_virtual_potential_temperature K [UPKA]
The virtual potential temperature of air is the potential temperature at which the dry air constituent of a parcel of moist air would have the same density as the moist air at the same pressure. To specify the standard pressure to which the quantity applies, provide a scalar coordinate variable with standard name reference_pressure." It is strongly recommended that a variable with this standard name should have a units_metadata attribute, with one of the values "on-scale" or "difference", whichever is appropriate for the data, because it is essential to know whether the temperature is on-scale (meaning relative to the origin of the scale indicated by the units) or refers to temperature differences (implying that the origin of the temperature scale is irrevelant), in order to convert the units correctly (cf. https://cfconventions.org/cf-conventions/cf-conventions.html#temperature-units).

Change Date: 11 Jun 2025, 4:45 p.m.

air_virtual_potential_temperature K [UPKA]
Potential temperature is the temperature a parcel of air would have if moved dry adiabatically to a standard pressure, typically representative of mean sea level pressure. To specify the standard pressure to which the quantity applies, provide a scalar coordinate variable with standard name reference_pressure. The virtual potential temperature of a moist air parcel is theoretically obtained and is the potential temperature of a similar dry air parcel that has been cooled so that its density is the same as in the moist air parcel. It is strongly recommended that a variable with this standard name should have a units_metadata attribute, with one of the values "on-scale" or "difference", whichever is appropriate for the data, because it is essential to know whether the temperature is on-scale (meaning relative to the origin of the scale indicated by the units) or refers to temperature differences (implying that the origin of the temperature scale is irrevelant), in order to convert the units correctly (cf. https://cfconventions.org/cf-conventions/cf-conventions.html#temperature-units).