Snow-avalanche modeling and hazard level assessment using statistical and physical modeling, DSS and WebGIS: case study from Czechia

Abstract:

Snow-avalanche modeling and hazard level assessment are important issues to be solved within mountain regions worldwide. In Czechia, there are two mountain ranges (Krkonoše and Jeseníky Mountains), which suffer from regular avalanche activity every year. Mountain Rescue Service is responsible for issuing avalanche bulletins. However, its approaches are still lacking objective assessments and procedures for hazard level estimations. This lack is mainly caused by missing expert avalanche information system.

This paper presents preliminary results from a project funded by the Ministry of Interior of the Czech Republic. This project is focused on development of an information system for snow-avalanche hazard level forecasting. It is composed of three main modules, which should act as a Decision Support System (DSS) for the Mountain Rescue Service.

Firstly, snow-avalanche susceptibility model is used for delimiting areas where avalanches can occur based on accurate statistical analyses. For that purpose a waste database is used, containing more than 1100 avalanche events from 1961/62 till present.

Secondly, a physical modeling of the avalanches is being performed on avalanche paths using RAMMS modeling code. Regular paths, where avalanches occur every year, and irregular paths are being assessed. Their footprint is being updated using return period information for each path.

Thirdly, snow distribution and stability models (distributed HBV-ETH, Snowtran 3D, Snowpack and Alpine 3D) are used to assess the critical conditions for avalanche release. For calibration of the models data about meteo/snow cover data and snowpits is used.

Those three parts are being coupled in a WebGIS platform used as the principal component of the DSS in snow-avalanche hazard level assessment.