Snow Stability and its Varation in Course of Time : International Snow Science Workshop

1998

S. 474-477

3 Abb., 8 Lit. Ang.

Bandaufführung

59426

One of the most important questions in avalanche warning is snowpack stability. A main factor when elaborating avalanche bulletins is the settlement of new snow and the stabilization of the snowpack (e.g. how long does it take that sufficient bands will exist between a weak layer and the recent snowpack (new snow). This paper shows some preliminary investigations on snow stability in March 1998. The measurements were done after a period of snowfall and included shear frame and Rutschblock tests as well as meteorological and nivological investigations. These data were used to determine snow stability in course of time and to compare those values with temperature and other relevant parameters. Results indicate that snow temperature might influence snow stability in a different way. If snow temperatures were relatively high (-2° to -3° C) the shear strength and the stability index increased considerably, in the case of lower temperatures those values did not change significantly, but the shear strength and the stability index decreased when the snow temperatures rised up (especially when the temperatures reached values near the freezing point).