Abstract
The National Research Institute for Earth Science and Disaster Prevention is improving an avalanche forecasting system based on the SNOWPACK model, which was developed by the Swiss Federal Institute for Forest, Snow and Landscape. It has been difficult to forecast avalanches caused by depth hoar (including faceted crystals) with high accuracy while using this system due to the wide range of shear strength. We previously proposed a model to estimate the shear strength during each stage of development for faceted crystals. In the present study, the avalanche forecasting system and the previously proposed model were used to calculate the stability index (SI) at the release zones of five avalanches that were observed in mountainous areas. Meteorological data from the station closest to each release zone were used as the input data of the system. In four of the five cases, a weak layer consisting of faceted crystals was reproduced for each release zone, and the calculated SI ranged from 1.1 to 2.7, which are values that indicate the occurrence of slab avalanches. This system was confirmed to be applicable to the forecasting of avalanches in mountainous areas, but only if a weather station is located near the avalanche release zone.
