Dual-Directional Radar Observation for Preliminary Assessment of the Ku-Band Broadband Radar Network

A short-baseline weather radar network consisting of Ku-band broadband radars (BBR) for meteorological application is under development. The BBR is a short-range and high-resolution Doppler radar for meteorological application, whose range and temporal resolution are several meters and 1 min per volume scan, respectively and coverage is from 50 m to 15 or 20 km. A radar network consisting of BBRs is useful for rapidly and accurately detecting and analyzing small-scale weather phenomena such as localized scattered thunderstorms, tornadoes, and downbursts in locations with a complex topography such as urban or mountainous area. The BBR network project plans to deploy three BBRs in the north Osaka, Japan, area and to observe and analyzing small-scale weather phenomena in detail. At present, two functioning BBRs have been deployed in the Osaka area. This paper presents a description of the BBR network project and its preliminary assessment. Observations of the two-BBR test bed derive expected properties of the three-BBR network, which efficiently covers troposphere in the overlapped area with a minimum observable altitude of tens of meters and a sensitivity of 10.2 dBZ (spatial average at a 5000-km altitude). Integrated reflectivity and preliminary algorithm for multiradar products in the two-BBR test bed, presenting a promising fine structure of precipitation cells, is also shown.