Snow Avalanches Mapping – Evaluation of a New Approach

Recent snow avalanche hazard mapping tools and procedures offer methods to improve the accuracy and reliability of risk and hazard localization.The validation of numerical mass movement models mainly depends on recorded historical avalanche data sets such as avalanche outlines and release volumes.These data sets are often unavailable or of an unknown accuracy.Avalanche characteristics such as release area, flow height and flow path, runout distance and total amount of released snow mass are essential parameters for proper calibration and evaluation of numerical simulation tools.Incorrectly calibrated models can influence decision-making which directly affects human safety.The acquisition of high quality data regarding observed avalanche events is often hindered by the high risk permanently present in avalanche terrain.This paper describes a promising method based on photogrammetry and computer vision and also introduces AVALMAPPER software that allows using a single terrestrial photograph with unknown exterior and interior orientation parameters to accurately map avalanche outlines.We evaluate this method by comparing its results with GPS measurements made in the field.We discuss the optimization of measurement efficiency, costs and human safety.