EVALUATION OF DUAL POLARIZATION RADAR FOR RAINFALL- RUNOFF MODELLING – A CASE STUDY IN SYDNEY,

Dual polarization radars have advantages that may translate into more accurate measurements of rainfall than are provided by conventional, single polarization radars. An investigation is performed into how much additional benefit will be delivered to practical rainfall-runoff modelling by dual polarization radar over the single polarization radar approach. The benefit of dual polarization is compared against the impact of using calibration raingauge networks for single polarization radar rainfall. The investigation is framed in the context of a case study: a widespread rainfall event of approximately two days duration producing a small flood in a partially urbanized basin of 354km area. Key Words: Single polarization radar, dual polarization radar; URBS rainfall-runoff model