earthkit.meteo.thermo.vapour_pressure_from_specific_humidity

earthkit.meteo.thermo.vapour_pressure_from_specific_humidity(q: ArrayLike, p: ArrayLike) → ArrayLike
earthkit.meteo.thermo.vapour_pressure_from_specific_humidity(q: xarray.DataArray, p: xarray.DataArray) → xarray.DataArray
earthkit.meteo.thermo.vapour_pressure_from_specific_humidity(q: earthkit.data.FieldList, p: earthkit.data.FieldList) → earthkit.data.FieldList

Compute the vapour pressure from specific humidity.

Parameters:

  • q (array-like | xarray.DataArray) – Specific humidity (kg/kg)

  • p (array-like | xarray.DataArray) – Pressure (Pa)

Returns:

Vapour pressure (Pa)

Return type:

array-like | xarray.DataArray

The computation is based on the following formula [Wallace2006]:

\[e = \frac{pq}{\epsilon (1 + q(\frac{1}{\epsilon} -1 ))}\]

with \(\epsilon = R_{d}/R_{v}\) (see earthkit.meteo.constants.epsilon).

Implementations

vapour_pressure_from_specific_humidity() calls one of the following implementations depending on the type of the input arguments:

The function returns an object of the same type as the input arguments.