CバンドMPレーダーによる地上雨量の精度と誤差要因

抄録

In recent years, flood damage and landslide disasters have occurred frequently due to increasing localized heavy rainfall. In order to capture the extensive surface precipitation in real time, Ministry of Land, Infrastructure and Transport (MLIT) has launched a real time surface rain observation system that combines the conventional XRAIN with C-band dual polarimetric radar. In this study, we have clarified observation characteristics of C-band dual polarimetric radar by comparing the surface rain gauge, X-band dual polarimetric radar and Radar-AMeDAS. As a result, C-band dual polarimetric radar has shown to have larger observation error from surface rain gauge than X-band dual polarimetric radar. One of the reasons is that the rainfall intensity changes vertically around the edge of the band-shaped precipitation system. The accuracy of the C-band dual polarimetric radar tends to decrease near the center of the cumulonimbus clouds, and the observation characteristics change with vertical wind.