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CF Standard Names (copied into data request to facilitate validation, particularly validation of consistency of definition in the CF standard with usage in the data request).
| Attribute | Value |
|---|---|
| canonical_units | K m s-1 |
| description | Covariance refers to the sample covariance rather than the population covariance. The quantity with standard name covariance_over_longitude_of_northward_wind_and_air_temperature is the covariance of the deviations of meridional air velocity and air temperature about their respective zonal mean values. The data variable must be accompanied by a vertical coordinate variable or scalar coordinate variable and is calculated on an isosurface of that vertical coordinate. "Northward" indicates a vector component which is positive when directed northward (negative southward). Wind is defined as a two-dimensional (horizontal) air velocity vector, with no vertical component. (Vertical motion in the atmosphere has the standard name "upward_air_velocity"). Air temperature is the bulk temperature of the air, not the surface (skin) temperature. It is strongly recommended that a variable with this standard name should have the attribute units_metadata="temperature: difference", meaning that it refers to temperature differences and implying that the origin of the temperature scale is irrelevant, because it is essential to know whether a temperature is on-scale or a difference in order to convert the units correctly (cf. https://cfconventions.org/cf-conventions/cf-conventions.html#temperature-units). |
| name | covariance_over_longitude_of_northward_wind_and_air_temperature |
| uid | 3ba66677-8ca2-11ef-944e-41a8eb05f654 |