X-Band Mini Radar for Observing and Monitoring Rainfall Events

Marco Allegretti, Silvano Bertoldo, Andrea Prato, Claudio Lucianaz, Oscar Rorato, Riccardo Notarpietro, Marco Gabella

CINFAI (Consorzio Interuniversitario per la Fisica delle Atmosfere e delle Idrosfere), unità locale presso Politecnico di Torino, corso Duca degli Abruzzi, Torino, Italy.
DET (Dipartimento di Elettronica e Telecomunicazioni), Politecnico di Torino corso Duca degli Abruzzi, Torino, Italy.
Envisens Technologies s.r.l., località Baraggino, Campus Tecnologico, Chivasso, Italy.
MeteoSwiss, Locarno Monti, Switzerland.

DOI: 10.4236/acs.2012.23026                

Abstract

Quantitative precipitation estimation and rainfall monitoring based on meteorological data, potentially provides continuous, high-resolution and large-coverage data, are of high practical use: Think of hydrogeological risk management, hydroelectric power, road and tourism. Both conventional long-range radars and rain-gauges suffer from measurement errors and difficulties in precipitation estimation. For efficient monitoring operation of localized rain events of limited extension and of small basins of interest, an unrealistic extremely dense rain gauge network should be needed. Alternatively C-band or S-band meteorological long range radars are able to monitor rain fields over wide areas, however with not enough space and time resolution, and with high purchase and maintenance costs. Short-range X-band radars for rain monitoring can be a valid compromise solution between the two more common rain measurement and observation instruments. Lots of scientific efforts have already focused on radar-gauge adjustment and quantitative precipitation estimation in order to improve the radar measurement techniques. After some considerations about long range radars and gauge network, this paper presents instead some examples of how X-band mini radars can be very useful for the observation of rainfall events and how they can integrate and supplement long range radars and rain gauge networks. Three case studies are presented: A very localized and intense event, a rainfall event with high temporal and spatial variability and the employ of X-band mini radar in a mountainous region with narrow valleys. The adaptability of such radar devoted to monitor rain is demonstrated.

Keywords

X-Band Radar; Rainfall Event; Precipitation Monitoring; Rain-Gauge Comparison; High Temporal Resolution; High Spatial Resolution; Rainfall Observation

Conflicts of Interest

The authors declare no conflicts of interest.

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