BrownIndex1#

class rojak.turbulence.diagnostic.BrownIndex1(total_deformation: DataArray, vorticity: DataArray)[source]#

Bases: Diagnostic

Brown Index 1 CAT diagnostic

Brown Index 1 is a simplifaction of [Roach1970]’s Richardson tendency equation. It was introduced in [Brown1973] and is defined as,

\[\frac{d\text{Ri}}{dt} = \sqrt{ 0.3 \zeta_{a}^{2} + D_{\text{sh}}^{2} + D_{\text{st}}^{2} }\]

where \(\zeta_{a}\) is the vertical component of absolute vorticity, \(\zeta\) is the vertical component of vorticity, \(f\) is the Coriolis parameter, \(D_{\text{sh}}\) is the shearing deformation and \(D_{\text{st}}\) is the stretching deformation.

Parameters:

  • vorticity (DataArray) – Vertical component of vorticity in m/s

  • total_deformation (DataArray) – Total deformation in m/s

__init__(total_deformation: DataArray, vorticity: DataArray) → None[source]#
Parameters:
Return type:

None

Methods

__init__(total_deformation, vorticity)

Attributes

computed_value

name