Flood estimation using radar and raingauge data

Flood hydrographs for the Finniss River catchment in Darwin, Australia, wer e calculated using different approaches to estimate the input rainfalls fro m the available radar and raingauge data. The rainfall estimation methods w ere: (1) using raingauge data alone; (2) using kriging of the raingauge dat a; (3) using radar data alone and (4) using cokriging of both radar and rai ngauge data. Both probability matching and power law methods were used to e stimate rainfall from measured radar reflectivities. The results showed tha t rainfall estimated by cokriging considerably improved flood estimates, be cause it optimally combines both the raingauge and radar data to improve th e estimate of subcatchment rainfall. (C) 2000 Elsevier Science B.V. All rig hts reserved.