'Considerable' rating

How would redefining the rating system change the way people make decision’s? The majority of accidents are always going to happen in the middle of the scale however it is structured… I would be concerned this setup would only shift the complacency if at all. I think the effects of complacency and large group dynamics should be a focus of discussion and education, I suspect those topics are the correlation in recent tragedies.

Kindly let me know if the following should be another thread.

From some comments above, it sounds like groups of 3-4 is the optimum for BC skiing safety in avalanche terrain.

Personally, I prefer groups of 5-6.  Small enough to maintain discipline when desired or needed (e.g., one-at-a-time and keep the person behind you - your rescuer! - in sight) plus plenty of diggers if anyone is completely buried.

What is the rationale for other group sizes?  Anyone have actual data regarding the affect of group size on recovery outcomes?

Thx
Mike

There's nothing wrong with the word "considerable" and the Considerable rating. It's defined in reasonably clear terms if you take the time to find the definitions as Charlie posted. All aspects of an avalanche forecast including its shorthand terms conceivably are subject to misinterpretation. Which can only really be mitigated if the reader has enough BC experience or training to know what forecasts mean practically.

What bugs me far more is the second guessing about the particular scale term used on the report on the day of some incident ("NWAC said the rating was only 'Considerable'. How could that happen?"). Too often this gets picked up or is started by people that don't really know that much about the role of avalanche forecasts in the bigger picture. Can be ONE decision point in the entirely personal process of staying alive in avalanche terrain but it's just one component of data that could be used, sometimes the least relevant one by the time you are actually on the hill.

What's more interesting to me anyways about using forecasts and scale isn't the "Likelihood" column in the definitions , it's the "Travel Advice" column. Considerable is "take time to consider whether the terrain you're on could be avalance terrain, even if it's not immediately obviously so", and High is "if there is ANY question in your mind of whether you're on avalanche terrain on this particular day ... you probably are."

It's been a while since I've posted, but this is a topic that interests me and I'm going to troll and then leave.

Now back to the topic. I think that the considerable rating is needed and is correct in its definition (without picking it apart). I think that the biggest trap has nothing to do with what the rating says, or is based on. The problem I think people have is: "Considerable" = "great fucking turns". As in, it has snowed enough that its deep and fresh, and human triggered slides are likely and naturals are possible.

A second observation in general is that spring warming is incredibly dangerous, though results vary to a high degree. As in, during the winter when its cold cohesive slabs are less widespread due to cold temps, but during the spring a bit of warming can easily turn a new dump from uncohesive and fun, to cohesive and dangerous quickly. So the line between "possible and likely" is more complex.

A bit about me. I ski in the Tahoe basin mostly, and I ski alone probably 50% of the time. I am scared of open terrain, but love skiing trees and chutes because I feel more comfortable making decisions there, even when its steep. For the sake of my background and experience I'll make the following gross generalization: avalanche conditions in Tahoe area can be dumbed down to danger increases towards the Sierra crest due to wind loading. So it's easy to have natural avalanches possible at the crest, and human triggered avalanches unlikely a 1/4 to 1/2 mile east. Somewhere in the moderate to considerable range most the time its snowed recently.

On another tangent, Craig Dostie has some words on variability and avalanche ratings from April 3 on earnyourturns.

Kindly let me know if the following should be another thread.

From some comments above, it sounds like groups of 3-4 is the optimum for BC skiing safety in avalanche terrain.

Personally, I prefer groups of 5-6.  Small enough to maintain discipline when desired or needed (e.g., one-at-a-time and keep the person behind you - your rescuer! - in sight) plus plenty of diggers if anyone is completely buried.

What is the rationale for other group sizes?  Anyone have actual data regarding the affect of group size on recovery outcomes?

Thx
Mike

Though not about recovery outcomes, there is some interesting data on the amount of risk that groups of difference sizes expose themselves to in "Heuristic Traps in Recreational Avalanche Accidents: Evidence and Implications" by Ian McCammon ( avalancheinfo.net/Newsletters%20and%20Ar...s/McCammonHTraps.pdf ).

"A number of investigators have suggested that party size may have played a role in decisions leading up to avalanche accidents. A “risky shift,” or the tendency of larger groups to take more risk, has been discussed frequently in the literature... there is a significant variation in exposure score by party size. It appears that people traveling alone and people traveling in parties of six to ten exposed themselves to significantly more hazard than people traveling in parties of four and more than ten people."  (check out the PDF to see the figure of the data)

Also later in the article: "...leaders appeared to make significantly riskier decisions as the group size increased."

What is the rationale for other group sizes?  Anyone have actual data regarding the affect of group size on recovery outcomes?

The group size has nothing to do with who lives or dies when caught in an avalanche, the focus should always be on stability and risk mitigation. Larger groups only have the possibility to hinder recovery outcomes.

personally I prefer groups 3 or less.
most all of my tours are with only 1 friend, occasionally two, rarely 3 or more, we get more skiing done and communicate safety and risk mitigation more efficiently. Admittingly that logic started with me wanting to get more skiing in on the tour without regard to avalanches. But what I found over time was the conversations on the tour became more in depth about snowpack and stability etc. and I learned a lot more about the snowpack than with any past larger groups. Occasionally I still go on yurt trips that always involve a large group and the stability assessment is much more complicated. I've seen groups split up over stability disagreements or sometimes everyone stares at the most experienced for the decision...

Kindly let me know if the following should be another thread.

it is off topic but its a good question.