Opportunistic Use of Microwave Satellite Signals for Early Flooding Detection and Real-Time Rainfall Field Reconstruction

Accurate weather forecasting, with updated information on a very short-term scale in time and space domains (the so-called nowcasting), is playing a dramatic role in many important aspects of everyday’s life. Nowcasting is particularly relevant for public safety, business-oriented services, and personal services, just to mention a few. For instance, the availability of reliable real-time forecast for hazardous and extreme weather conditions, such as cloudburts and thunderstorms, may effectively reduce the threat to life and property, thanks to timely emergency rescue operations. This branch of meteorology has been made possible by a combination of factors, including the availability of low-cost and low-consumption sensors, and the proliferation of new information and communication technologies, which made the distribution and the application of real-time weather information possible at nearly any location. Quantitative precipitation estimation can in fact be obtained by several observing systems using different measurement principles that have different time and space resolutions, and accuracies [1]. For instance, rain gauges (RGs) and disdrometers are point devices which can measure the accumulated rainfall (in mm) during a given amount of time and at a given location. Remote sensing devices, such as satellite sensors, though available on a global scale, suffer from scarce time and space resolution, whereas weather radars have a higher temporal (from 5 to 10 minutes) and spatial resolution (less than 1 km, although not uniform). Note also that there are regions of the globe where networks of sensing devices (in some cases, including RGs) are not available