International Snow Science Workshop Proceedings - Montana State University Library

Item: Using Near Infrared Photography to Link Spatial Patterns in Stratigraphy with Stability

• • Title: Using Near Infrared Photography to Link Spatial Patterns in Stratigraphy with Stability

    Proceedings: 2010 International Snow Science Workshop

    Authors:

    • Edward Bair  [ Donald Bren School of Environental Science and Management, Univeristy of California - Santa Barbara ]  [ US Army Corps of Engineers Cold Regions Research and Engineering Laboratory ]

    Date: 2010

    Abstract: A majority of avalanche research has focused on persistent layers. In comparison, we know very little about non-persistent weak layers despite their prevlance in ski areas and other areas with predominantly articial triggers. One study (Brown and Jamieson 2006) nds that failure layers in new snow are less dense and composed of larger crystals than adjacent strata, while another (Stethem and Perla 1980) nds failure layers in new snow are denser than the slab, but that crystal types are often the same. Micropenetrometer studies of new snow (Pietzch 2009; Peilmier 2003) and observations of atmospheric forms (Casson et al. 2008) show that new snow is highly stratied, especially in wind exposed areas like avalanche starting zones. Fist hardness new snow, classied as a uniform layer by traditional methods, can actually vary in hardness by an order of magnitude over 10cm (Pietzch 2009). The competing eects of stress and compaction from overburden cause substantial changes within hours (Birkeland et al. 2006). The dyanimic nature of the position and strength of new snow requires a new approach to stability modeling. Stability models that assume the weak layer exists in a static location are not correct. For new snow avalanches, preliminary results suggest failure layers are often not substantially dierent optically than the slab. Because of the high proportion of avalanches that fail at the interface or in storm snow, we propose a spatially distributed stability index model that examines stability at all depths to predict small to large avalanches for ski areas.

    Object ID: ISSW_P-008.pdf

    Language of Article: English

    Presenter(s): Unknown

    Keywords: near infrared photography, spatial patterns, stratigraphy, stability

    Page Number(s): Unavailable

    Subjects: infrared photography spatial patterns stratigraphy

  • Get Full Article

    Get Full Abstract

Back to Home page