Microwave active sensors and river basin hydrology Available to Purchase

Recent disastrous floods in Italy as well as in other countries prone to floods and flash floods evidence the need to predict precipitation on a catchment with high space-time resolution, with benefit from the most advanced observing systems and nowcasting procedures as to allow effective countermeasures to be taken in a very short time lag. In this work the point is made on the contribution of microwave active sensors to reach this goal, from microwave disdrometers, cloud radars (Ka and W band), multi-parametric precipitation (C band ) radars, and space-borne past (CP on Cloudsat ) or planned (Global Precipitation Mission) active sensors, alone or in combination. MW disdrometers have recently shown their capability, and better performance with respect to optical and impact ones, in characterizing Drop Size Distribution with high temporal resolution, giving useful indications of variability of this parameter at the surface. The immediate diagnosis of stratiform or convective character of the precipitation is also helpful in instant precipitation estimate. MW disdrometers were also capable to show the dependence of drop break up size with altitude. A network of MW disdrometers combined with mobile Ka band cloud radar is proposed as a tool to integrate ground C (or X or S) regular meteorological radar returns from the area catchment. It is shown how the three MW active sensors can integrate for the correct precipitation input in hydrological models of the river basin. Finally the role of space-borne radars is discussed when they happen to inspect the same catchment area simultaneously with the other sensors.