Title Microstructural resistance of snow following first wetting
Author Techel, F.; Pielmeier, C.; Schneebeli, M.
Author Affil Techel, F., WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland
Source Cold Regions Science and Technology, 65(3), p.382-391, . Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0165- 232X
Publication Date Mar. 2011
Notes In English. Based on Publisher- supplied data GeoRef Acc. No: 309960
Index Terms precipitation (meteorology); avalanches; density (mass/volume); grain size; hydrology; liquid phases; mass movements (geology); measurement; penetrometers; snow; stability; statistical analysis; strength; microstructure; water; unfrozen water content; wet snow; Switzerland- -Swiss Alps; Alps; atmospheric precipitation; Central Europe; density; depth; Europe; liquid phase; mass movements; Swiss Alps; Switzerland; ultrastructure; water content
Abstract One of the main causes for the formation of wet snow avalanches is the decrease in strength following the introduction of liquid water. The influence of liquid water on initially dry snow was investigated in twelve field experiments in the Eastern Swiss Alps. For this, a variety of different snow types were artificially wetted and liquid water content (using the Snow Fork), microstructural penetration resistance (Snow Micro Penetrometer, SMP) and snow density were measured. Measurements were repeated up to eight times resulting in a total 1100 liquid water content, 355 penetration resistance, and 737 snow density measurements. Following wetting, microstructural penetration resistance decreased in layers consisting of faceted crystals or depth hoar at low liquid water content. Layers consisting of precipitation particles or small round grains, on the other hand, showed no significant trend at a similar water content. The results indicate that first wetting of faceted crystals and depth hoar layers has an impact on snow strength, and consequently contributes to a decrease in snow stability.
URL http://hdl.handle.net/10.1016/j.coldregions.2010.12.006
Publication Type journal article
Record ID 65006892