relative_humidity_from_mixing_ratio#
- metpy.calc.relative_humidity_from_mixing_ratio(pressure, temperature, mixing_ratio)[source]#
Calculate the relative humidity from mixing ratio, temperature, and pressure.
- Parameters:
pressure (
pint.Quantity
) – Total atmospheric pressuretemperature (
pint.Quantity
) – Air temperaturemixing_ratio (
pint.Quantity
) – Dimensionless mass mixing ratio
- Returns:
pint.Quantity
– Relative humidity
Examples
>>> from metpy.calc import relative_humidity_from_mixing_ratio >>> from metpy.units import units >>> relative_humidity_from_mixing_ratio(1013.25 * units.hPa, ... 30 * units.degC, 18/1000).to('percent') <Quantity(67.1277085, 'percent')>
Notes
Employs [WMO8] eq. 4.A.16 as derived from WMO relative humidity definition based on vapor partial pressures (eq. 4.A.15).
\[RH = \frac{w}{\epsilon + w} \frac{\epsilon + w_s}{w_s}\]\(w\) is mixing ratio
\(w_s\) is the saturation mixing ratio
\(\epsilon\) is the molecular weight ratio of vapor to dry air
\(RH\) is relative humidity as a unitless ratio
Changed in version 1.0: Changed signature from
(mixing_ratio, temperature, pressure)