Starting with the likelihood definition and terms in the Conceptual Model of Avalanche Hazard (Statham et al., 2018), Scott Thumlert, Grant Statham and Bruce Jamieson present some ideas for improving avalanche likelihood and how it can be communicated. Presented at the Virtual Snow Science Workshop, October 2020. CC BY-ND.

How do avalanche practitioners decide which runs, roads or backcountry terrain to open and when to close areas down? In this 12 minute video, John Stimberis, Larry Stanier and Bruce Jamieson attempt a high level overview of the decision process. September 2020. CC BY-ND.

A technical video for avalanche practitioners and recreationists interested in avalanche science. The video outlines the formation of faceted layers near melt-freeze crusts, the persistence of these layers as potential failure layers for slab avalanches and some ideas on anticipating the resulting slab avalanches. Bruce Jamieson and Scott Savage, June 2020. CC BY-ND

A video to start discussion about whether visualization will help us rate avalanche size on the D-scale. By Bruce Jamieson, Montse Bacardit, Ethan Greene and Ian Tomm. May 2020. CC BY-ND.

Photos of 15+ avalanches so you can practice rating their size with the more visual method and compare your rating to ours. Bruce Jamieson, Montse Bacardit, Ethan Greene and Ian Tomm. May 2020. CC BY-ND.

When salt is added to snow, the snow cools because heat from the snow flows into concentrated salt water around the salt grains. The surprisingly large amount of heat required for melting (i.e. latent heat) contributes to avalanche formation in at least two ways. March 2020. CC BY-ND.

This video outlines some general advantages and disadvantages of avalanche decision aids. The advantages and disadvantages are general enough that – I hope – both backcountry recreationists and avalanche practitioners find something useful in this video. This video does not explain how to use any decision aids but does show four decision aids and identify where to find more information on them. March 2020. CC BY-ND.

A case study for avalanche practitioners about a difficult winter in which a weak layer of facets on a melt-freeze crust produced avalanches - including many large hard-to-forecast avalanches - throughout the winter. February 2020. CC BY-ND.

A successful avalanche operation starts with good planning. This 9-minute video highlights some aspects of avalanche planning for those who work in avalanche operations. On many planning projects, the planning team includes practitioners with operational experience. February 2020. CC BY-ND.

Ski cutting by recreationists is controversial. Are these 9 essentials too conservative? Too risky? Or is the subject taboo? January 2020.

In this seven-minute video, Jamieson shares six tips that he believes can reduce the avalanche risk while skiing and riding in the mountains in winter. December 2019.

Highlights of a paper on the risk of ski cutting by Bruce Jamieson, Karl Birkeland, Mark Vesely, Ilya Storm, John Stimberis. August 2019. CC BY-ND.

By understanding the differences between snow avalanches and other slope hazards, the authors of Planning Methods for Assessing and Mitigating Snow Avalanche Risk hopefully made it accessible to specialists who plan for other slope hazards. Bruce Jamieson. February 2019. CC BY-ND.

Although intended for avalanche operations, some backcountry recreationists may also find this video useful. January 2019. CC BY-ND.

Promo for the new e-book edition of Backcountry Avalanche Awareness (36 seconds).

A video for advanced recreationists and avalanche practitioners about a poorly understood phenomenon that has surprised - sometimes tragically - many experienced people in the backcountry. September 2019.

A field experiment shows major limitations of IR images of the pit wall for avalanche forecasting. However, some images - including some free ones - are excellent for avalanche education. Bruce Jamieson and Mike Smith. January 2019. CC BY-ND.

An instructional video about the energy exchange at the snow surface and some of the persistent weak snowpack layers formed primarily by the energy exchange.

Bruce Jamieson, November 2017. Revised 31 December 2017.

CC by-nd

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Simple illustrations of brittle and ductile fractures. Snow can fail and fracture in the same ways as toffee.

For a skier, snowmobiler or other load to trigger a slab avalanche: the dynamic load must start a crack in a weak snowpack layer and then crack propagation must be sustained away from the load.
There is no one paper that summarizes the ideas in this video, but you could start by searching for "simenhois fracture propagation" and read the short 2009 article.
Bruce Jamieson, 2016, CC by-nd.

This video presents the technical concepts behind the current theory for the spontaneous release of dry slab avalanches. There are a few questions and answers at the end for keeners. Bruce Jamieson and Juerg Schweizer, 2016, CC by-nd.

This video presents a simplified quantitative risk analysis for an object of value that is fixed in a snow avalanche path. The concepts can be adapted moving objects such as vehicles or people and for other mass movements.
Bruce Jamieson, CC by-nd.

This is a sequel to the video on quantitative risk analysis for a structure in an avalanche path. Bruce Jamieson, 2016, CC by-nd.

Climate change has been a focus for the avalanche world over the last few years. The Asarc group at the University of Calgary recently contributed two papers to the discussion, which we have summarised in this video. 2015, CC by-nd.

Hopefully, this will spark discussion on how to classify avalanche size, especially for big avalanches. There is also another discussion video on a practitioner survey and the use of half sizes.

Bruce Jamieson, Ruedi Beglinger, Doug Wilson, 2014, CC bj-nd.

This should trigger discussion on the use of half sizes, uncertainty and "those other columns" in the definitions. Bruce Jamieson, 2014, CC by-nd.

Based on an ISSW 2009 paper by Bruce Jamieson, Juerg Schweizer and Cora Shea, the presentation uses an event tree, an expert survey of triggering odds, Canadian Accident data and some large assumptions to calculate the risk of death for a day of backcountry skiing at each of the levels of regional avalanche danger. The backcountry skiing risks are compared with the risks for a day of kayaking, a day of rock climbing and a day of mountaineering. During Considerable avalanche danger, backcountry skiing risk is about 10 times higher than when the avalanche danger is Moderate. CC by-nd.

This presentation is based on a paper by Bruce Jamieson and Alan Jones for the ISSW in Alaska in September 2012. It reviews risk concepts then summarizes quantitative vulnerability for buildings, people in buildings, people in vehicles and people in the backcountry. The paper is at www.ucalgary.ca/asarc/Issw2012_Vulnerability_JamiesonJones

CC by-nd.

This presentation explains the basics of daytime snowpack warming over terrain and introduces SWarm.
SWarm is a free spreadsheet that uses the maximum solar radiation to estimate daytime warming 10 cm below the surface over idealized terrain. You can select the date, latitude, expected cloud cover, and days since snowfall to see how these factors can influence the daytime snowpack warming down 10 cm.

For more on SWarm, see www.ucalgary.ca/asarc/system/files/SWarm_Issw08_Bakermans.pdf

Bruce Jamieson and Laura Bakermans, 2011, CC bj-nd.

This video summarizes an objective way of assessing a snow profile - whether or not the snow is likely to be skier triggered. Most of the calibration data came from the Columbia Mountains of western canada.

To read the paper behind this video, search for: asarc yellow flags
To read McCammon and Schweizer's paper on lemons, search for: Mcammon lemons.

Bruce Jamieson and Juerg Schweizer, 2015, CC by-nd.

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This video uses a simple avalanche forecasting problem for a ski area to illustrate Bayes Rule, which is a method for updating a numerical probability based on new information. It is applied to pre-season planning - helping to set the threshold precipitation for control; however, Baysian updating could be applied more frequently, e.g. on a day by day basis. Bruce Jamieson, 2012, CC by-nd.

This presentation is similar to one presented at the ISSW 2013 in Grenoble France. The paper corresponding paper is posted at www.ucalgary.ca/asarc/issw2013/Iso31k_Jamieson

Bruce Jamieson and Alan Jones, 2013, CC by-nd.

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This presentation video for advanced recreationists and practitioners identifies the five types of fracture character and shows the frequency of skier triggering on slopes that exhibited each type of fracture character in compression tests. The frequency of skier triggering is also presented for each type of fracture character separately for easy, moderate and hard taps. Bruce Jamieson, 2011, CC by-nd.