Disaster Prevention Research Institute, Kyoto University
Abstract
In the present study, we have developed the ‘Database of Sakurajima Volcanic Ash Fall Distributions’ (VASH), which is based on weather radar observations. VASH provides basic information on eruption events, such as the eruption onset time, eruption cloud top height, horizontal distributions of ash fall amounts and ash fall durations, and the temporal changes of total ash fall amounts and total ash fall areas. VASH also provides specific information that is derived from a variety of research radars. X-band polarimetric radar provides the temporal change of the vertical structure of an eruption cloud on the range height indicator display. Marine radar provides information on the development of an eruption column, at 2.5 second intervals. The relationship between ash fall amount and the radar reflectivity factor is provided for each eruption event. VASH contributes studies not only on volcanic hazard prevention but also on eruption cloud dynamics, and ash cloud micro physics
