solve_toon89_picaso

exo_skryer.RT_em_schemes.solve_toon89_picaso(be_levels: Array, dtau_layers: Array, ssa: Array, g_phase: Array, be_internal: Array, return_layer_contrib: bool = False) → Tuple[Array, Array, Array]

Toon et al. (1989) thermal emission solver with multi-stream quadrature.

This scheme integrates the radiative transfer equation over angle using Gaussian quadrature with 8 streams (4 nodes × 2 hemispheres). It solves the full two-stream equations with exponential terms and tridiagonal matrix inversion.

Parameters:

be_levelsndarray, shape (nlev, nwl)

Planck function at level interfaces in W m⁻² sr⁻¹.

dtau_layersndarray, shape (nlay, nwl)

Optical depth per layer (dimensionless).

ssandarray, shape (nlay, nwl)

Single-scattering albedo per layer (0-1).

g_phasendarray, shape (nlay, nwl)

Asymmetry parameter (Henyey-Greenstein) per layer.

be_internalndarray, shape (nwl,)

Internal heat flux at bottom boundary in W m⁻² sr⁻¹.

return_layer_contribbool, optional

If True, return contribution function per layer. Currently not implemented for Toon89 scheme (returns zeros).

Returns:

lw_up_fluxndarray, shape (nlev, nwl)

Upward longwave flux at each level in W m⁻².

lw_down_fluxndarray, shape (nlev, nwl)

Downward longwave flux at each level in W m⁻².

layer_contrib_fluxndarray, shape (nlay, nwl)

Layer contribution function (zeros for Toon89).

Notes

The Toon89 scheme is more accurate than the alpha-EAA method for optically thick atmospheres with strong scattering, but is also more computationally expensive due to the tridiagonal solve per wavelength and quadrature integration.

References

Toon et al. (1989), “Rapid calculation of radiative heating rates and photodissociation rates in inhomogeneous multiple scattering atmospheres” Journal of Geophysical Research, Vol. 94, No. D13, pp. 16,287-16,301.