dewpoint_from_specific_humidity#
- metpy.calc.dewpoint_from_specific_humidity(*args, **kwargs)[source]#
Calculate the dewpoint from specific humidity and pressure.
- Parameters:
pressure (
pint.Quantity
) – Total atmospheric pressuretemperature (
pint.Quantity
, optional) – Air temperature. Unused in calculation, pending deprecationspecific_humidity (
pint.Quantity
) – Specific humidity of air
- Returns:
pint.Quantity
– Dew point temperature
Examples
>>> from metpy.calc import dewpoint_from_specific_humidity >>> from metpy.units import units >>> dewpoint_from_specific_humidity(1000 * units.hPa, 5 * units('g/kg')) <Quantity(3.79314079, 'degree_Celsius')>
Changed in version 1.6: Made temperature arg optional, to be deprecated
Changed in version 1.0: Changed signature from
(specific_humidity, temperature, pressure)
Notes
Employs [WMO8] eq 4.A.6,
\[e = \frac{w}{\epsilon + w} p\]with
\[w = \frac{q}{1-q}\]\(q\) is specific humidity
\(w\) is mixing ratio
\(\epsilon\) is the molecular weight ratio of vapor to dry air
to calculate vapor partial pressure \(e\) for dewpoint calculation input. See
dewpoint()
for additional information.