brunt_vaisala_period

metpy.calc.brunt_vaisala_period(height, potential_temperature, vertical_dim=0)

Calculate the Brunt-Vaisala period.

This function is a helper function for brunt_vaisala_frequency that calculates the period of oscillation as in Exercise 3.13 of [Hobbs2006]:

\[\tau = \frac{2\pi}{N}\]

Returns NaN when \(N^2 > 0\).

Parameters

• height (xarray.DataArray or pint.Quantity) – Atmospheric (geopotential) height

• potential_temperature (xarray.DataArray or pint.Quantity) – Atmospheric potential temperature

• vertical_dim (int, optional) – The axis corresponding to vertical in the potential temperature array, defaults to 0, unless height and potential_temperature given as xarray.DataArray, in which case it is automatically determined from the coordinate metadata.

Returns

pint.Quantity or xarray.DataArray – Brunt-Vaisala period. Given as pint.Quantity, unless both height and potential_temperature arguments are given as xarray.DataArray, in which case will be xarray.DataArray.

Changed in version 1.0: Renamed heights, axis parameters to height, vertical_dim

See also

brunt_vaisala_frequency, brunt_vaisala_frequency_squared, potential_temperature

brunt_vaisala_frequency_squared friction_velocity