virtual_potential_temperature#
- metpy.calc.virtual_potential_temperature(pressure, temperature, mixing_ratio, molecular_weight_ratio=<Quantity(0.62195691, 'dimensionless')>)[source]#
Calculate virtual potential temperature.
This calculation must be given an air parcel’s pressure, temperature, and mixing ratio. The implementation uses the formula outlined in [Markowski2010] pg.13.
- Parameters:
pressure (
pint.Quantity
) – Total atmospheric pressuretemperature (
pint.Quantity
) – Air temperaturemixing_ratio (
pint.Quantity
) – Dimensionless mass mixing ratiomolecular_weight_ratio (
pint.Quantity
or float, optional) – The ratio of the molecular weight of the constituent gas to that assumed for air. Defaults to the ratio for water vapor to dry air. (\(\epsilon\approx0.622\))
- Returns:
pint.Quantity
– Corresponding virtual potential temperature of the parcel
Examples
>>> from metpy.calc import virtual_potential_temperature >>> from metpy.units import units >>> virtual_potential_temperature(500 * units.hPa, -15 * units.degC, 1 * units('g/kg')) <Quantity(314.87946, 'kelvin')>
Notes
\[\Theta_v = \Theta \frac{\text{w} + \epsilon}{\epsilon\,(1 + \text{w})}\]Changed in version 1.0: Renamed
mixing
parameter tomixing_ratio