|Topic Review (Newest First)|
|04-16-2014 09:48 AM|
For the record. I think the whole pit test thing is going to be thrown out of the Level 1 curriculum. Not that your post is incorrect. The problem AIARE and other avalanche organizations are seeing is that people are using pits as a reason to go instead of the other reason around. Especially when if you are even questioning what is going on, you probably have already received your answer.
Lots of things are changing. The Project Zero effort is to get info from the recreational users and evaluate what is working now, and what could be done differently. So those participating in the discussions and questionnaires are actually helping shape the program. It has been a long time since Level 1 & 2 have had an overhaul. I am interested in seeing where it goes. Much better people than me are working hard on this.
|04-13-2014 03:39 PM|
Generally avalanche center reports do not usually include ski areas where avalanche control work is done. Ski patrol does report their observations and results to the avalanche center which gives the center a better grasp for the regional snow pack conditions.
What the original poster observed was the result of patrol`s avalanche reduction work before opening Heather Canyon. They are very conservative when opening that terrain and often it is closed even though the conditions there are stable, but Wy East above is not and the entire Heather/Clark Canyon complex is a huge terrain trap. They don't want that canyon full of people if Wy East were to go and send billions of tons of snow into it.
Neni, the pit and column tests should always be considered your "verification check" to either back up or disprove what you already should know about the snow pack conditions. It is also a way for you to get a feel for the season`s history in the snowpack much like looking at tree rings. The pit can give you a great indicator of the aspect you are about to ride though if the site is chosen well. It is also a good practice to try to dig a hasty pit at top, middle and bottom of the aspect you intend to ride if it is possible.
|04-09-2014 10:41 AM|
Yes, the guy giving the avy course stressed that a snowprofile dig has minor worth since the snowpack will be different every odd meter as the terrain profile/wind changes, just gives you a general idea on the profile in that very spot. Nevertheless I found it very illustrative to actually see and feel the different layers.
Just read the last accident report in Switzerland... two dead in an avy triggered by a break/collaps of a cornice - it was avy danger level 1 that day, a certified guide and a guest.
|04-09-2014 08:26 AM|
Generally speaking a meter and a half or five feet (as mhaas stated) deep is the area you effect the snow pack. I usually dig down 5 1/2-6 feet to build in a little room for error. Again, though, if I am that concerned, I am probably already leaning towards a plan B or C descent.
Loading is definitely a huge red flag. Observed over days or in plain sight. It is something to pay attention too and often avoid.
|04-09-2014 08:00 AM|
Originally Posted by killclimbz View Post
|04-09-2014 06:45 AM|
The DPS problem is a tough one. As mhaas said, it depends on where the tipping point is. They are generally described as low probability-high consequence events. Your chances are not great that you'll cause one, but if you do, you won't survive.
The Sheep Creek accident that claimed five lives on Loveland Pass here in Colorado was a deep persistent slab event. Three days earlier a snowboarder was killed in Avalanche (yeah I know irony) bowl on Vail pass from the same thing.
I know personally that when these are being harped on by our local avalanche center, I give the type of terrain where they are found a wide berth. Generally speaking it is alpine and treeline areas. They can break very deep in the snow pack, and things like snow pits, column tests, ECT's, tell you pretty much nothing about them. Even when it is just a persistent slab problem, which is the deep persistent slab's mean little brother. Easier to trigger since it is a near surface problem. That is what killed my friend George on New Year's Eve. His group dug several pits and observed no instability. As soon as he deviated from the line they spoke about riding, it let loose and strained him through trees. Not very survivable. This is one of the primary reasons I do not like to put a lot of stock into pits. Too many people are looking for an all clear when in reality a pit is just a very small part of the info you should be using to decide if it is a good choice to ride any given slope.
|04-08-2014 08:34 PM|
This feb in the Uinta mountains, pic from the UAC website..
Its my understanding that resorts don't report avalanches to the public because it will make gapers from Kentucky think that they will die on a green run. But they do report most slides to the local avalanche center.
Neni, it depends how close the slab is to over loading the weak layer but your generally correct about a persons body weight only effecting the top 5 feet.
One of the scarier parts of these deep persistent slab avalanches is that you can trigger a relatively benign storm slab that will be enough to overload the deep slab and step down, taking the whole slope with you.
|04-08-2014 07:48 PM|
Originally Posted by killclimbz View Post
Originally Posted by wrathfuldeity View Post
Is it likely to trigger such a deep slide on such deep instable layer by hiking/riding? Meant as a question out of curiosity, no criticism intended, since I've learned to do a snowprofile about 1.5m/5ft deep and was given the reason for this depth is that the pressure you put on the pack fades with depth i.e. week layers beneath do not matter since you don't impact them anymore..
|04-08-2014 10:19 AM|
|ShredLife||.... like wrath said: welcome to the PNW. when it goes big out here its big.|
|04-08-2014 09:25 AM|
Originally Posted by chomps1211 View Post
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