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PostPosted: Thu Oct 15, 2009 5:59 pm
by Diggler
jddeetz wrote:Thanks for all the great advice guys... I now have a few peaks in mind to build a foundation from.

Here is a bonus question someone may know the answer to:
A while ago I took an avalanche safety course in which they mentioned something about snowpack consisting of multiple layers of snow from different storms. When there is a dense snow layer on top of a light powdery layer, there is potential for an avalanche to occur.
A) So being that the ice axe is best used with a thick layer of snow bordering on ice, is it safe to say that whenever I have to pull out the ice axe I am in avalanche territory?
B) Is this why I never see anyone using an ice axe with snow shoes on (Because snow shoes are used for light snow, ice axe is for hard snow)?
C) Is there any way to predict the thickness of a snowpack to determine what equipment I will need?


Time to take another avalanche course (official Level I is a great intro)- I need to take another one myself...

Without doing an in-depth (no pun intended) analysis, a snowpack's stability is dependent on a couple of things. Slab avalanches are the big, dangerous ones that you don't want to be a part of- when a piece of slab of a given layer(s) release over other(s)- these can potentially go all the way to the ground. This is caused by poor bonding to the layer underneath. Poor bonding can be due to different things. Often when a new layer is forming a slab over an old one (i.e. it's snowing) & the temperatures are low, there is poor bonding, making for potentially unsafe conditions- a good bond is achieved when the new layer 'sticks' to the underlying one, e.g. when the temp's are warmer. During extended periods of low temp's (not frequently seen in the Sierra so much as, say, in the Rockies), depth hoar can form in layers of already questionable stability, creating unsafe conditions as well. A red flag for travel in avalanche country is during or immediately after a big storm- this overloads the underlying layers & can create conditions where a small point load (like you crossing an unstable slooe) could let the whole thing loose. In short, do as much reading as you can, & even better a Level I (for starters) course, about avalanches, what causes them, & terrain that is relatively 'safe' & those to avoid. There are plenty of books on the subject. Mountaineering: Freedom of the Hills has a good intro to this, as well as the basics (& beyond) of travel with crampons & an axe.

Snowshoes/skis usually work better in softer snow (although modern skis & skins do an amazing job of sticking to harder stuff too), crampons for hard, steep stuff. As already mentioned, although snowshoes do have their place for backcountry winter travel, skis will often times be WAY more preferable...

Thickness of the snow isn't going to determine what equipment you use (unless it's deep Sierra cement, where you'll want snowshoes or skis to avoid postholing all day)- it's more the TYPE of snow that will dictate what your tools will be. On the other hand, if you're seriously concerned about snow layers, thickness, bonding, etc. you'll want a shovel (requisite for traveling in potential avalanche terrain anyway, along with a beacon & probe) to do a Rutschblock test.

If just getting into it, start slow & acquaint yourself with different types of snow, ice, & travel thereon. Stick to the treeline (or under) unless you're confident the snow above won't slide. Going to Yosemite in the winter (again, Badger Pass area) is a great way to learn the basics of snow travel, winter camping, etc.

Lassen & Shasta both have great areas to figure out how to get around with crampons & an axe, once the snow hardens.

Good luck!