vertical_velocity#
- metpy.calc.vertical_velocity(omega, pressure, temperature, mixing_ratio=0)#
Calculate w from omega assuming hydrostatic conditions.
This function converts vertical velocity with respect to pressure \(\left(\omega = \frac{Dp}{Dt}\right)\) to that with respect to height \(\left(w = \frac{Dz}{Dt}\right)\) assuming hydrostatic conditions on the synoptic scale. By Equation 7.33 in [Hobbs2006],
\[\omega \simeq -\rho g w\]so that
\[w \simeq \frac{- \omega}{\rho g}\]Density (\(\rho\)) is calculated using the
density()
function, from the given pressure and temperature. Ifmixing_ratio
is given, the virtual temperature correction is used, otherwise, dry air is assumed.- Parameters:
omega (
pint.Quantity
) – Vertical velocity in terms of pressurepressure (
pint.Quantity
) – Total atmospheric pressuretemperature (
pint.Quantity
) – Air temperaturemixing_ratio (
pint.Quantity
, optional) – Mixing ratio of air
- Returns:
pint.Quantity
– Vertical velocity in terms of height (in meters / second)
Examples
>>> from metpy.calc import vertical_velocity >>> from metpy.units import units >>> vertical_velocity(-15 * units('Pa/s'), 700 * units.hPa, 5 * units.degC) <Quantity(1.74463814, 'meter / second')>
See also