| Summary: | A statistical topographical model for the computation of runout for snow avalanches in Iceland has been derived from a recently assembled data sel of long Icelandic snow avalanches. The avalanches are from hills above towns in western, northern and eastern Iceland. The model, a = O.85ß, expresses the average slope of the avalanche path, a, as directly proportional to the average slope of the avalanche track, ß. A similar model for a dala sel of avalanches collected through systematic investigations of several regions in western Norway is found to be a = 0.93 ß. The residual standard error in a for the models is similar, O"ó,a = 2. 20 for the Icelandic dala and O"ó,a = 2.10 for the Norwegian data. The models thus indicate that avalanches in the Icelandic data set reach somewhat further than avalanches in the Norwegian dala set for similar ß-angles, but the relationship between aand ß-angles in the two data sets is nevertheless quite similar (cf Fig. 2). Worthwhile improvements in the models were not obtained by adding intercept or curvature terms or terms corresponding to other parameters than ß. Statistical models based on run out ratios were not found to be an improvement over models based on a- and ß-angles.
|
|---|