Saturday, February 27, 2010
Clearly I'm not a Samurai
Its a Mine Field Out There
21 significant, human triggered avalanches in the backcountry
9 unintentionally triggered
7 people caught
4 partial burials including one with just his hand sticking out"
(http://utahavalanchecenter.org/advisory/slc)
Depth Hoar is not a common problem in the Wasatch because our temperatures are more moderate than you would see in an continental snow pack (like the rockies) and so we tend to be not so good at dealing with it, as the above statistics would dictate. I would say our most common snow tests are different compression tests, like the extended column test, but unfortunately they don't really work because they only tell you the conditions of the localized are that you are testing. The slope 10 feet away could have a aspect change of 10 degrees and have a completely different level of stability. So in lies the problem. Finding an accurate 'test slope' is tricky, if not impossible.
On Thursday I was out in Days/Davenport Ridge doing some death crust skiing and ventured into the North aspect of Days do a quick extended column test and the results were, well.... terrifying? The test slope I used was 38 degrees about 98ooft on a directly North aspect. On entering the test slope some things come clearly into view as I see lightnng cracks shoot out in front of me through the snow, a sure sign of propagation. Also before of the was up on about a 26 degree slope the entire new soft slab settled... a difficult experience to explain but it sounds something like an empty dumpster being dropped from 4 feet in the air. Very disturbing. Already by the time I started doing my test I was pretty certain what the results would be. Once I had completed my construction I did the test... three taps on the shovel from the wrist.... 1 tap from the elbow and like a breaking rubber band, the whole column released on a perfectly clean sheet of depth hoar. No deformation, or residual consolidation what so ever. Its difficult to explain how unstable AND unpredictable this snow pack is at the moment, but as I was tip-toeing back to my car with fear and trembling the analogy o the mine field came to mind. Our North aspect slopes are really like mine fields... the mines are where the surface hoar is buried. So if you lucky, you could ski that 38 degree slope and never hit a mine... like the 2 tracks I observed on the NNW aspect off the top of Davenport Hill. But just as likely is hitting 20 mines as you go down and releasing all 18 inches of new snow.... on the entire slope--enough to cause serious injury or death.
I'm not a professional, and I clearly don't work for the Utah avalanche center, but I am interested in the difference between the considerable rating and the high rating as I would be inclined to place a high rating on our Northerly aspect slopes greater than 35 degrees (and a considerable on greater than 30) in the common surface hoar zones which it seems they have determined to be mostly between 8-10,000ft. This task, I might add, of determining what altitudes and aspects the surface hoar is at is very, very difficult. Many pitts need to be dug, local knowledge needs to be applied based on previous years experience, and maybe some magical upper level meteorological skills.
So if
you are going off in the BC today maybe stay off, or out from below, anything Northerly greater than about 30 degrees: its a mine filed out there.
Thursday, February 11, 2010
"Children: are your parents making wise choices in the backcountry?"
I must say I got a chuckle out of this line from Brett at the Avalanche center this morning. But it seems that some time someone is going to have to ski those lines right? Well, its probably not going to be me! There is always someone younger and braver right? (This isn't an encouragement to go ski steep North aspects lines)
So I know most people haven't been enjoying the lack of snow, but I have really been appreciating it recently. The last two days I spend skiing some new lines (for me) that have a certain aesthetic appeal, as apposed to well... the normal Utah draw. First was little pine @ 3300ft straight up out of the car and then directissmo, 3200ft although not right out of the car... Both are steep south facing lines that have tight couloirs, big slide paths, and no fall zones. Tomorrow I'm thinking Tanners would add up nicely. (so that means you can't go there unless I've invited you)
One of the fun extra exciting things about directissmo is that you start in a large gully that cliffs out in every location but one. So you can't really ski off any where you want, you need to follow the exact route which neither of us had skied before, but we did see some of it from the road. So when we crest superior we go into a cloud back with very little visibility. I know the ridge we follow so we start off down the catwalk hoping for the clouds to raise but they don't. So I have no visual aids, I left the compose in my other ski pants, and I've never skied the route before. So what do you do with a single point exit or fall to your death? Jump in of course! So off we go very, very carefully down into the gully in search for the directissmo chute. Once we get a little lower we start to see the slope roling over to what we assume is the rock face. After tipptoeing around we find the entrance, unfortunately we are a little low and have to 'huck' the 3 foot cornice into the chute. With much pain and suffering I finallly commit and it turns out to be easy, and most importantly a safe, rock hard snow pack.
Up until this point we didn't shoot any photo's or video because the focus and tension was high, so all of your shots will be below the entry to directissmo. Enjoy! Oh and in case you wanted to go there, the skiing could be described as either breakable death crust or cement that spilled out of a cement truck on the freeway.