montgomery_streamfunction

metpy.calc.montgomery_streamfunction(height, temperature)

Compute the Montgomery Streamfunction on isentropic surfaces.

The Montgomery Streamfunction is the streamfunction of the geostrophic wind on an isentropic surface. This quantity is proportional to the geostrophic wind in isentropic coordinates, and its gradient can be interpreted similarly to the pressure gradient in isobaric coordinates.

Parameters

• height (pint.Quantity or xarray.DataArray) – Array of geopotential height of isentropic surfaces

• temperature (pint.Quantity or xarray.DataArray) – Array of temperature on isentropic surfaces

Returns

stream_func (pint.Quantity or xarray.DataArray)

Notes

The formula used is that from [Lackmann2011] p. 69.

\[\Psi = gZ + C_pT\]

• \(\Psi\) is Montgomery Streamfunction

• \(g\) is avg. gravitational acceleration on Earth

• \(Z\) is geopotential height of the isentropic surface

• \(C_p\) is specific heat at constant pressure for dry air

• \(T\) is temperature of the isentropic surface

See also

get_isentropic_pressure, dry_static_energy

Examples using metpy.calc.montgomery_streamfunction

Isentropic Analysis

kinematic_flux potential_vorticity_baroclinic