Abstract
Most severe disasters have included extreme rainfall intensity. Consequently, it is necessary to develop rainfall observation technology that provides observations over a large area over a short-term, with high accuracy. This study was conducted to clarify the accuracy of X-band multi-parameter radar (X-MP) over the Hokuriku region using rain-gauge data collected by the Japan Meteorological Agency (JMA) and the Water and Disaster Management Bureau under the Ministry of Land, Infrastructure, Transport and Tourism (MLIT). Additionally, this study analyzed results in terms of installed altitudes of rain-gauge stations and distance from the radar site to the rain-gauge station.
Results of statistical analyses show that the distance from the radar site engenders lower accuracy of the X-MP.However the X-MP data accuracy was equal to that of rain-gauge data within a 20 km radius from the radar site. Although the X-MPs provide observations with high accuracy for rainfall observation, snowfall observation was less accurate. Therefore,quantitative snowfall estimation might improve the observation accuracy of the X-MP. Examination of the Z-R relation and the KDP-R relation shows that Z-R might provide better accuracy than KDP-R beyond a 30 km radius from the radar site. Results suggest the necessity of using and analyzing more observation data.
