dewpoint#

metpy.calc.dewpoint(vapor_pressure)#

Calculate the ambient dewpoint given the vapor pressure.

Parameters

vapor_pressure (pint.Quantity) – Water vapor partial pressure

Returns

pint.Quantity – Dewpoint temperature

Examples

>>> from metpy.calc import dewpoint
>>> from metpy.units import units
>>> dewpoint(22 * units.hPa)
<Quantity(19.0291018, 'degree_Celsius')>

Notes

This function inverts the [Bolton1980] formula for saturation vapor pressure to instead calculate the temperature. This yields the following formula for dewpoint in degrees Celsius, where \(e\) is the ambient vapor pressure in millibars:

\[T = \frac{243.5 \log(e / 6.112)}{17.67 - \log(e / 6.112)}\]

Changed in version 1.0: Renamed e parameter to vapor_pressure

Examples using metpy.calc.dewpoint#

Dewpoint and Mixing Ratio

Dewpoint and Mixing Ratio

Dewpoint and Mixing Ratio