mixsea.shearstrain.gm_strain_variance

mixsea.shearstrain.gm_strain_variance(m, iim, N)[source]

GM model strain variance.

Parameters:
  • m (array-like) – Vertical wavenumber vector [rad/m].

  • iim (array-like) – Wavenumber integration range, indexer to m.

  • N (float) – Local buoyancy frequency [s^-1].

Returns:

  • Sgm (float) – GM strain variance normalized by N^2 [1/m^2].

  • Pgm (array-like) – GM strain spectrum for wavenumber range m.

Notes

Returns GM strain variance by integrating Pgm over a wavenumber range of the GM shear spectrum as presented in Kunze et al. (2006) [8] eq. 10:

\[\frac{_{GM}\left< V_z^2\right>}{\overline{N}^2} = \frac{\pi E_0 b j_\ast}{2} \int_{m_\mathrm{min}}^{m_\mathrm{max}} \frac{m^2 dm}{(m + m_\ast)^2}\]

with \(j_\ast=3\), \(E_0=6.3\times10^{-5}\), \(N_0=5.2\times 10^{-3}\) rad/s, \(b=1300\) m, and

\[m_\ast = \frac{\overline{N}}{N_0}\frac{\pi j_\ast}{b}\]

Note that this corresponds to the buoyancy-normalized GM shear variance divided by 3.

See also

gm_shear_variance

GM shear variance