20100419

Module 2: Tux Avy Bulletin Assignment

For this assignment, you can choose any day of the season in between Modules 1 and 2, but wait until the regular five-point scale Mount Washington avalanche bulletins have started up for the season (usually around late November or so).
But don't wait until the last minute (and remember the deadlines posted at the student checklist), since certain periods will provide better opportunities than others.

First, read these two articles:
Then, periodically monitor:
Take a day of your choosing (can be during that day, or later on after-the-fact with hindsight), but try to avoid days when the decisionmaking is far too obvious (e.g., weather and/or avalanche conditions so poor that travel is infeasible, or a stretch of "Low" avalanche danger that allows relatively safe travel everywhere).

Write up a very brief summary of the avalanche forecast for Tuckerman Ravine that day, including the recent weather conditions and season-long snowpack characteristics that have led to that forecast.
Then create a simplified avalanche danger rose, showing the rating by aspect and elevation, using the data in this aspect summary spreadsheet if necessary.
Also identify the relevant avalanche "Problems" for which you can use this spreadsheet version of the new AIARE Avalanches and Observations Reference.
For each "Problem" separate out on a five-point scale the Probability (with "Likely" and "Unlikely" at opposite ends of the scale) and "Size" (with "Large" and "Small" at opposite ends of the scale).
And identify the Trend over the next 24 hours (either Increasing Danger, Same, or Decreasing Danger).

So far you have essentially reverse-engineered a typical regional avalanche forecast out of the Tuckerman Ravine micro-scale avalanche forecast.
But now you need to ski -- somewhere in the Presidentials other than Tuckerman (or Huntington) Ravine.

Pick some other Presidentials location at- and/or above-treeline . . . which actually has enough snow to ski!
 (If you're not familiar with the various options, just choose Gulf of Slides ski trail into Gulf of Slides.)

Prepare a touring plan (for the same day whose avalanche bulletin you've assessed), including a marked-up map showing your routes for both ascent (in green) and descent (in red), using an online mapping tool such as CalTopo or any of Presidentials-specific map resources and the previously referenced aspect summary spreadsheet.
Utilize the Decision-Making Framework and "STOP" series of questions as referenced in the assigned Volken backcountry skiing book.
Complete a section of either your own field book or these sample pages from the 2012 AIARE field book.
You can also use this slope angle estimation tool.
And try to obtain aerial imagery from different aspects and angles, especially from Google Earth.

This should be contained a single pdf file, to be emailed to the Instructor of Record (by the deadline noted in the student checklist), who will then email it to your fellow students.
On the evening of the first day of the Winter Field Sessions, you will present your touring plan to your fellow students (demonstrating your proposed route on the Presidentials diorama at PNVC), as if all of you were contemplating going on this tour (albeit with a smaller group size, and more familiarity among the group members), so the primary feedback will come from your fellow students.
Hence each student's completed assignment will constitute yet another assignment for all the other students. 

Some key issues to address in your touring plan:
  • How does your route compare to Tuckerman Ravine in terms of aspect, pitch, elevation, and fetch areas?
  • What are the major factors contributing to the ratings in the USFS avalanche bulletin, and how might these major factors differ from your chosen location?
  • What recent conditions reports are available for your chosen location?
  • What do you think the avalanche conditions will be for your chosen route?
  • Who are you partners?
  • How familiar are you with the terrain?
  • If conditions turn out to be other than expected, do you have appealing and accessible alternatives?
Major caveat: if this assignment seems hard, that's because . . . it is!
We don't expect anyone to come up with a perfect assessment here -- after all, the difficulty of this assignment is precisely why even the professional USFS snow rangers limit themselves to only two glacial cirques (and even omit many prominent ski lines in one of them).

However, the process of completing this assignment will force you to assess many important factors, as well as keep you periodically in touch with Presidentials conditions . . . and also prompt you to think about the implications of skiing outside the specifically forecasted areas.

Moreover, Tuckerman and Huntington Ravines are the only backcountry skiing destinations with such micro-scale forecasting, so limiting our avalanche course to applying the Tuckerman Ravine forecast to only . . . Tuckerman Ravine would fall far short of the skills you should acquire from a L1 avalanche course.

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