[2-3] Special

Three-dimensional rainfall structure measured in 30 seconds by phased array weather radar

Shinsuke Satoh, Fusako Isoda, Hironori Iwai, Hiroshi Hanado (NICT), Fumihiko Mizutani (Toshiba Corp.), Shigeharu Shimamura, Yuki Hirano, and Tomoo Ushio (Osaka Univ.)

The first X-band phased array weather radar (PAWR) in Japan was developed and installed at Osaka University, Suita in 2012. The PAWR measures three-dimensional (3D) fine structure of rainfall with 100 m range resolution and about 100 elevation angles in 30 seconds. A 3D animation of radar echoes visualized in every 30 seconds reveals the kinematic change of reflectivity core and the growth process of precipitation. From observation data in a day, a first echo appeared at an altitude of about 5 km in an isolated cumulonimbus cloud, and fallen to the ground in 10 to 15 minutes. The result shows the ability of short-term prediction or now-cast of localized heavy rainfalls using PAWR data. In 2014, the second PAWR was installed at NICT advanced ICT Research Institute, Kobe. In the overlapped area observed by the two PAWRs, advanced data analyses (e.g. dual-Doppler analysis, correction of rainfall attenuation) are expected.