Parametrization of Cloud Fields: Simple Models for the Probability of a Clear Line-of-Sight

This study is focused on modeling the morphological properties of cloud fields by the instrumentality of the probability of a clear line-of-sight (PCLOS). Depending on the assumed effective cloud geometry, PCLOS is expressed by different power functions of zenithal angle and cloud field parameters. Generally, the equations are very complicated and hard numerical procedures are required for retrieving the cloud field parameters from radiometric data. In this study three simplified parameterization of PCLOS are proposed, aiming to use standard numerically methods for solving the equations and, therefore, to increase the accuracy of the estimated parameters. The results demonstrate that a simple linear approximation of PCLOS can lead to a similar accuracy in point cloudiness estimation as the more sophisticated models.