ANALYSIS AND SYNTHESIS OF CLOUD PATTERN FOR RADIATION-FIELD STUDIES

A method for the analysis of small scale, short term characteristics o f radiations fields under intermediate sky conditions (clouds of cumul us type) is described. It is based on the extraction of cloud field st ructures from sky photographs. The cloud structures are described as f ractal objects. Based on this representation a procedure for the gener ation of synthetic cloud pattern and related radiation fields is given . Statistical characteristics of synthetic irradiance data sets are co mpared with empirical data from an array of ground sensors.