earthkit.meteo.thermo.array.mixing_ratio_from_dewpoint

earthkit.meteo.thermo.array.mixing_ratio_from_dewpoint(td, p)

Compute the mixing ratio from dewpoint.

Parameters:

• td (array-like) – Dewpoint (K)

• p (array-like) – Pressure (Pa)

Returns:

Specific humidity (kg/kg)

Return type:

array-like

The computation starts with determining the vapour pressure:

\[e(w, p) = e_{wsat}(td)\]

where:

• \(e\) is the vapour pressure (see vapour_pressure_from_mixing_ratio())

• \(e_{wsat}\) is the saturation_vapour_pressure() over water

• \(w\) is the mixing ratio

Then w is computed from \(e\) using mixing_ratio_from_vapour_pressure().