Testes de um modelo de propagação de radiação solar em atmosfera de múltiplas camadas.

Abstract

The present work implements a model of transfer of solar radiation (visible spectrum) in a layered atmosphere in 16 layers. The scheme has stochastic structure where the diffuse photons take a random walk in the atmosphere until reaching an absorbent state (in the sky, in a layer or in the ground). The associated formalism (a first order Markov chain) allows the calculation of planetary reflectance, of surface irradiance and absorption rates in each layer. The basic data required for the implementation are the reflectance, the absortance and the transmittance, for direct and diffuse radiation, in each layer. These parameters were evaluated by delta-SS approach of two flows. The results were compared with those of other published works, applied to standard situations (haze-L, Cúmulus Cl, Rayleigh atmosphere with and without zonium, mean atmosphere tropical of McCLATCHEY). Good accuracy of the model is verified when evaluating planetary reflectance and global surface irradiance. The main advantages of the model used are: simple structure, adaptation to an arbitrary number of layers and good precision.