IDENTIFICATION OF VERTICAL PROFILES OF RADAR REFLECTIVITY FOR HYDROLOGICAL APPLICATIONS USING AN INVERSE METHOD .2. SENSITIVITY ANALYSIS AND CASE-STUDY

A method of identification of the vertical profile of reflectivity, fo rmulated by the authors in an accompanying paper, is tested through a sensitivity analysis. Two simulated but realistic profiles(with and wi thout brightband effects) are used. The radar features and the statist ical parameters involved in this method are allowed to vary around sta ndard values in order to understand their influence on the results. Th e main conclusion is that, for a given radar configuration, results of acceptable quality can be obtained with a single adjustment of the me thod for the two types of profiles, which suggests the approach is ope rationally applicable. To complement this theoretical analysis, actual profiles of reflectivities are studied for two rainfall events observ ed in the Cevennes region of France. The efficiency of the proposed me thod is appreciated from a hydrological point of view. A comparison is performed at the basin scale between hourly rainfall intensities, mea sured with a dense network of rain gauges and radar data. The analysis shows that the introduction of the identification and the correction of the influence of vertical profiles of reflectivity improve the accu racy of rainfall estimates from radar data.