A broadband simplified version of the Solis clear sky model

The Solis clear sky model is a new scheme based on radiative transfer calculations and the Lambert–Beer relation. When used on large geographical scale to convert meteorological satellite images into radiation data, the radiative transfer calculations are too computer time consuming. To circumvent this problem, a broadband simplified analytical version of the Solis model is presented in this note. The accuracy for the clear sky beam, global and diffuse irradiance components compared to the original model are, respectively, 1%, 2% and 5% with no bias.