TurbulenceIndex2#

class rojak.turbulence.diagnostic.TurbulenceIndex2(u_wind: DataArray, v_wind: DataArray, vector_derivatives: dict[VelocityDerivative, DataArray], geopotential: DataArray, total_deformation: DataArray, divergence: DataArray)[source]#

Bases: Diagnostic

Turbulence Index 2 CAT diagnostic

Turbulence Index 2 was proposed by [Ellrod1992] and is a simplification of the Petterssen’s frontogenesis function from [Mancuso1966] which relates the rate of change in temperature gradient on a constant pressure surface due to deformation. This is then related to the vertical wind shear through the thermal wind relation. Turbulence Index 2 retains the divergence term and is defined as,

\[\text{TI2} = S_{v} \times ( \text{DEF} - \delta)\]

where \(S_{v}\) is the vertical wind shear, \(\delta\) is the divergence, i.e. \(\delta = \frac{ \partial u }{ \partial x } + \frac{ \partial v }{ \partial y }\)

Parameters:

  • u_wind (DataArray) – Zonal wind speeds in m/s

  • v_wind (DataArray) – Meridional wind speeds in m/s

  • vector_derivatives (dict[VelocityDerivative, DataArray]) – Dictionary containing du/dx and dv/dy derivatives

  • geopotential (DataArray) – Geopotential in m^2/s

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

  • divergence (DataArray) – Horizontal divergence of wind in m/s

__init__(u_wind: DataArray, v_wind: DataArray, vector_derivatives: dict[VelocityDerivative, DataArray], geopotential: DataArray, total_deformation: DataArray, divergence: DataArray) → None[source]#
Parameters:
Return type:

None

Methods

__init__(u_wind, v_wind, vector_derivatives, ...)

Attributes

computed_value

name