The raman option includes single order rotational Raman scattering in the calculation. By default, the raman option is deactivated. The solution treats Raman as a perturbation similar to the approaches of (Vountas et al., 1998) and (Spurr et al., 2008). The raman option may only be used for spectral calculation. The disort radiative transfer solver with a general source is needed to solve the radiative transfer equation when including Raman scattering. This solver is automagically invoked when specifying the raman option. The raman option is optimized with respect to speed. The optimized implementation should be just as accurate as the original version.
Vountas, M., Rozanov, V.V., & Burrows, J.P., (1998), "Ring effect: impact of rotational Raman scattering on radiative transfer in Earth's atmosphere." J. of Quant. Spectrosc. Radiat. Transfer. Vol. 60, pp. 943‒ 961.
Spurr, R., de Haan, J. D., van Oss, R., & Vasilkov, A., (2008), "Discrete ordinate radiative transferin a stratified medium with first order rotational Raman scattering." J. of Quant. Spectrosc. Radiat. Transfer. Vol. 109, pp. 404‒ 425.