earthkit.meteo.thermo.specific_humidity_from_relative_humidity

earthkit.meteo.thermo.specific_humidity_from_relative_humidity(t: ArrayLike, r: ArrayLike, p: ArrayLike) → ArrayLike
earthkit.meteo.thermo.specific_humidity_from_relative_humidity(t: xarray.DataArray, r: xarray.DataArray, p: xarray.DataArray) → xarray.DataArray
earthkit.meteo.thermo.specific_humidity_from_relative_humidity(t: earthkit.data.FieldList, r: earthkit.data.FieldList, p: earthkit.data.FieldList) → earthkit.data.FieldList

Compute the specific humidity from relative_humidity.

Parameters:

  • t (array-like) – Temperature (K)

  • r (array-like) – Relative humidity(%)

  • p (array-like) – Pressure (Pa)

Returns:

Specific humidity (kg/kg) units

Return type:

array-like

The computation starts with determining the the vapour pressure:

\[e(q, p) = r \frac{e_{msat}(t)}{100}\]

where:

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

  • \(e_{msat}\) is the saturation_vapour_pressure() based on the "mixed" phase

  • \(q\) is the specific humidity

Then \(q\) is computed from \(e\) using specific_humidity_from_vapour_pressure().

Implementations

specific_humidity_from_relative_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.