Kunihiro Yamada

Modeling of Flowing Avalanches considering 3-Dimensional Topography and Development of Numerical Simulator

Yusuke Fukushima

An avalanche is classified into two kinds according to movement and form. A flowing avalanche is an avalanche which moves so that it may flow without snow flurries and occurs at the beginning of Spring. On the other hand, a powder snow avalanche generates many snow flurries; this type of avalanche is especially common as a result of the severe winter weather.A large part of Japan is mountainous. Many villages and large structures have the potential of damage by both flowing avalanche and powder snow avalanches. In order to prevent these disasters, an understanding of both the flow avalanches and the powder snow avalanches are necessary. A hazard map can be based on such knowledge. Also, it should be possible to build facilities preventing these calamities.In this research, the numerical simulator on flowing avalanche is developed by means of input data concerning the 3-D topographical features of the avalanche. Once this is done, the result will be compared with Osawa�fs (2003) analysis of a powder snow avalanche and the actuality of an avalanche itself.