earthkit.meteo.thermo.vapour_pressure_from_mixing_ratio

earthkit.meteo.thermo.vapour_pressure_from_mixing_ratio(w: ArrayLike, p: ArrayLike) → ArrayLike

earthkit.meteo.thermo.vapour_pressure_from_mixing_ratio(w: xarray.DataArray, p: xarray.DataArray) → xarray.DataArray

earthkit.meteo.thermo.vapour_pressure_from_mixing_ratio(w: earthkit.data.FieldList, p: earthkit.data.FieldList) → earthkit.data.FieldList

Compute the vapour pressure from mixing ratio.

Parameters:

• w (array-like | xarray.DataArray) – Mixing ratio (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:

\[e = \frac{pw}{\epsilon + w}\]

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

Implementations

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

• earthkit.meteo.thermo.array.vapour_pressure_from_mixing_ratio() for array-like

• earthkit.meteo.thermo.xarray.vapour_pressure_from_mixing_ratio() for xarray.DataArray

• earthkit.meteo.thermo.fieldlist.vapour_pressure_from_mixing_ratio() for FieldList

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