The use of meteorological radar in flood mitigation: some preliminary results

Rainfields estimation over a catchment area is an important stage in many hydrological applications. In this context, weather radars have several advantages, since a single site is able to obtain coverage over a vast area with high temporal and spatial resolution. In this work, we investigated the areal reduction factor (ARF) by using radar reflectivity maps collected with the Polar 55C weather radar. Radar rainfall estimations were integrated for heavy rainfall with an upscaling process, until we had rainfall estimation over an area of 900 km2. Results obtained for several rainfall events by using this technique are compared with the most important relations of ARF in literature. Furthermore, the calibration of the GDSTM model, a cluster stochastic generation model in continuous space and time, is hereby presented. For the validation of the ability of the model to reproduce internal structure of rain events, a geo-morphological rainfall-runoff model, based on width function, was calibrated using simulated and observed data.