tartes 0.9

Two-stream radiative transfer in snow model

TARTES is a fast and easy-to-use optical radiative transfer model used to compute snow albedo (spectral and broadband) and energy absorption profile. TARTES represents the snowpack as a stack of horizontal homogeneous layers. Each layer is characterized by the snow specific surface area (SSA), snow density, impurities amount and type, and two parameters for the geometric grain shape: the asymetry factor g and the absorption enhancement parameter B. The albedo of the bottom interface can be prescribed. The model is fast and easy to use compared to more elaborated models like DISORT - MIE (Stamnes et al. 1988). It is based on the Kokhanovsky and Zege (2004) formalism for weakly absorbing media to describe the single scattering properties of each layers and the delta-eddington approximation to solve the radiative transfer equation. Despite its simplicity, it is accurate in the visible and near-infrared range for pristine snow as well as snow containing impurities represented as Rayleigh scatterers (their size is assumed much smaller than the wavelength) whose refractive indices and concentrations can be prescribed.

TARTES is compatible with Python 2.7x and 3.4.