Multifractal analysis and simulation of rainfall fields in space

Statistical downscaling of precipitation from the large scales of meteorolo gical models to the characteristic response scales of small catchment basin s needs to correctly preserve the anomalous scaling laws observed in real r ainfall. Multifractal behaviour of precipitation in space is investigated o n a set of rainfall fields obtained by a high resolution simulation with a limited area model for numerical weather prediction and on two sets of rada r measures of rainfall during the GATE campaign. Some sets of synthetic rai nfall fields were generated applying a multifractal model based on a wavele t expansion with coefficients extracted by a log-Poisson random cascade, an d results of comparisons with the GATE rainfall fields are presented. (C) 1 998 Elsevier Science Ltd. All rights reserved.