SIMULATION AND MODELING OF RAINFALL RADAR MEASUREMENTS FOR HYDROLOGICAL APPLICATIONS

A procedure is described for the simulation of rainfall radar reflecti vity (absolute and differential) measurements by dual linear polarizat ion meteorological radars. The basic requirement that the proposed pro cedure aims at satisfying is that radar data obtained at the end of th e process be correlated in a physically plausible manner to the rainfa ll field at ground, the latter being generated by means of a stochasti c space-time rainfall model. The main goal of the model is to give the possibility to easily check the accuracy of radar rainfall estimates derived by means of procedures and algorithms aimed at minimizing or c ompensating for the effects of measurement errors associated with seve ral types of meteorological events, with particular reference to requi rements of hydrogeological forecast systems. Within the limits imposed by the validity of the adopted model, an analysis was carried out ind icating general criteria that may be adopted to achieve a better accur acy in rainfall estimates and a full exploitation of the advantages of fered by the radar dual polarization measurement technique.