In our last post about WYSAW, we want to highlight a talk given by James Floyer. James talked about gathering information and making decisions. We are always interested in learning about others’ decision-making tools. Check it out:
The Dangerator: A tool for Estimating Avalanche Danger – James Floyer
James Floyer is one of the lead forecasters for the Canadian Avalanche Centre and helped develop a tool for estimatingavalanche hazard in areas without forecast centers. It’s an interesting tool that when ‘verified’ to predicted danger levels in current forecast zones typically was hitting the assessed level ~70% of the time and within one level almost all of the time. If anything it would tend to assess a higher hazard than underpredicting it. It tended to overpredict more often in the spring when the snow moved into an isothermal state. This was not a novice tool, but any AST1 grad (CA) or level one grad (US) would be able to apply it. Simple enough that I won’t go into explaining it:
The questions put forth for the decision steps are:
- Critical Loading – “Do you expect roughly 30cm or more of new snow, or significant wind, or rain during the period of 24 hours prior to and up to the end of your day”
- Critical Warming – “Do you expect a rapid rise in temperature to near or above 0°C or the upper snowpack to become wet due to strong sun, above freezing temperatures or rain?”
- Recent Loading – “Has there been loading within the past 48 hours, including roughly 30cm or more of new snow, or significant wind, or rain”
- Slab Avalanches – “Are there signs of slab avalanches in the area from today or yesterday”
- Persistent Slab Problem – “Is there a persistent or deep persistent slab problem in the snowpack?”
More details on these decision questions can be found in Table 1 of James’ ISSW paper. http://arc.lib.montana.edu/snow-science/objects/ISSW2018_O15.2.pdf