Towards a better understanding of the mechanical properties of snow controlling crack propagation after loading

Dr. Karl Birkeland

U.S. Forest Service National Avalanche Center
Montana State University, USA


Fellowship Period: 01.2020-05.2020

As the Director of the Forest Service National Avalanche Center, Karl provides guidance to 13 regional avalanche warning centers throughout the United States, as well as being responsible for the Forest Service’s military artillery for avalanche control program.  In addition, he conducts applied avalanche research and works with graduate students and other colleagues to transfer new and emerging technology to field personnel.  Karl has worked with snow and avalanches for nearly 40 years as a professional ski patroller, backcountry avalanche forecaster, and avalanche researcher.

Activities within WSL Fellowship

This project is being conducted in collaboration with Dr. Alec van Herwijnen (SLF Avalanche Formation Team Leader) and Bastian Gerling (SLF PhD student).  We seek to better understand temporal changes in the mechanical properties of snow related to crack propagation following a loading event.  Our work involves carefully loading weak layers by sieving snow onto the existing snowpack in the field.  This project extends and improves on some of our recent work by:

  1. Collecting additional datasets to better investigate and understand different slab and weak layer combinations,
  2. Utilizing a SnowMicroPen to make direct measurements of critically important snow mechanical properties, and
  3. Assessing the field data with more advanced video techniques that require a high definition and extremely high speed video camera that is available at SLF.


Our results will help to improve our knowledge of how the snowpack begins to stabilize in the minutes and hours following loading events, and will hopefully help us better forecast changes in avalanche conditions during this critical time period.

Cooperation within WSL

Interne Kontakte (Datensätze)

Cooperation outside of WSL

For the avalanche flow dynamics of extreme events in Colorado, I will be working with Dr. Ethan Greene and Mike Cooperstein of the Colorado Avalanche Information Center.  For comparing the effectiveness of stability tests, I will be working with Doug Chabot, Alex Marienthal, and Jim Earl of the Gallatin National Forest Avalanche Center.  I will also be in touch with numerous additional colleagues from the U.S. and Canada for various other smaller projects.