PLANE-PARALLEL EQUIVALENCE OF A HETEROGENEOUS CLOUD - CASE OF CONSERVATIVE SCATTERING

The study of radiative transfer in an inhomogeneous medium lacks a wel l established theoretical framework to describe effect of the inhomoge neity on the apparent radiative properties of the scattering medium. I n this paper, we study the radiative transfer in two-dimensional multi fractal clouds, completely characterized by a single multifractal para meter, by using a four-stream radiative transfer model. We show it is possible to define an ''equivalent optical thickness'' of an inhomogen eous cloud. This enables the treatment of an inhomogeneous cloud as an equivalent plane parallel homogeneous cloud, which is much easier to deal with.