 Poster: A snowHead
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The Swiss Wall is steep enough at the top to slough off, but getting hit by slough is only a real risk there if it carries you into a pylon or you've ducked the rope skier's right - in which case you're skiing above a cliff band.
Personally I'd prefer to be hit by slough on the Swiss Wall and take a tumble in soft snow than take a tumble on it after the snow's settled.
On the "cutting" thing - it's not unreasonable to suggest that you should seek to minimise risk to people below you by not skiing directly above them.
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How steep is the swiss wall out of interest. I've done it but don't know the exact angle.
So, when you say it could slough, that is wet or dry snow?
Why could it not have slabs?
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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| PhillipStanton wrote: |
| I don't know about other people, but I find this stuff really difficult to internalise because of all the variables. It's a complete bug to apply. |
looks like this may be out of print but it is really good for converting the theory into practice (ie answering the question as to whether or not to ski a particular slope)
covers things like the 3x3 and Munther risk reduction techniques
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Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
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| PhillipStanton wrote: |
| marmot wrote: |
| read this book (at the very least) before even thinking of venturing off piste |
I've done four evening talks; a six day long professional course; read probably six or seven books and done lots of transciever search practice.
All I know is that I (honestly) know diddly squat.
I don't know about other people, but I find this stuff really difficult to internalise because of all the variables. It's a complete bug to apply. |
I would think your snowpack awareness should be very good judging from your above comments.
One thing to remember at the end of the day is to keep interpretations as simple as possible, yea its great if you can understand the complexities of snow crystal shapes and how they bond/dont bond, or how supersaturation causes sublimation and deposition to produce the 10 types of snow crystal.
But all said and done, when Im on the hill either teaching or for my own pleasure all I want to know is what is the depth and bonding like of the weakest layer, its that simple, yes there maybe 15 layers, but I only want to know about the one that is going to slide 
Probably the best reference book for the man in the street is Avalanche by Robert Bolognesi, this guy is the leading person in avalanche study along with our own Blyth Wright.
It also contains the simple to use avalanche prediction wheel NivoTest, which quite frankly is the muts nuts.
http://www.amazon.co.uk/Avalanche-Understand-Avalanches-Cicerone-Mini-guides/dp/1852844736/ref=sr_1_14?ie=UTF8&s=books&qid=1228131481&sr=8-14&tag=amz07b-21
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mark handford, nice recommendation - I am now £15 poorer!
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Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
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Arno, Ah you bought both, the snow book is more indepth regarding formation, solar radiation and the more complex parts, but its still a good reference book, it includes a snow crystal observation card, all that would top this off would be a magnifying glass or linen tester glass.
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You'll need to Register first of course.
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To get back to the original question I think the instructor was answereing a question posed by someone who has very little knowledge on the topic and was giving him an answer that would keep him as safe as possible with no knowledge.
A little knowledge can be dangerous especially when it comes to avalanch, Beginner powder fiends have very little concept of snow bonding/Layers and slope angles therefore the general rule advice given in this case was a very clever bit of advice
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Ordhan, Totally agree with the guides response in the original post, it was a simple and standard comment that even the most novice of skiers would understand.
In a similar context we get many phone calls each winter asking if Snowdonia is open !!!! (if they have to ask if the mountains are open then they shouldnt really be going in to them!).
Our comments are that it may be best if you catch the train up to the view point and not to bother venturing out unprepared and ill equiped in a winter mountain environment.
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Actually the instructor said that's what he was taught in avalanche school but he said not to bother with the advice in Engelberg as the sun on the glacier made new snow bond quickly 
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You'll get to see more forums and be part of the best ski club on the net.
You'll get to see more forums and be part of the best ski club on the net.
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mark handford, got the avalanche book and the Nivo test and agree it is a really good, simple guide and certainly helps determine levels of risk.
im with phillipstanton take on all of this though. Did the same mountain safety course (risk 4 all week) dug snow pits and looked as snow crystals talked about aspects etc. BUT i could never get to a simple yes no answer when trying to evaluate a slope. I know it never is Black and White but i didnt really understand when to say "absolutely no way we should ski that", the fall back position always seemed to be "ski one at a time"
For instance we dug several snow pits, used a shovel to determine how easy the snow pack broke free, poked our fingers/hands in to see the layers, looked for depth hoar etc etc but after doing all of that could I tell if i should go ahead and ski a particular pitch... NOPE
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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Arno, thanks good article in that link... I kinda like the simple Nivotest or 3x3 method. I guess the point i was trying to make is that you can use these methods but when standing on top of a good looking pitch begging to be skied experience seems to be the best tool. Although i enjoyed learning about snow conditions, pits, weather, etc. I really cant see the point (for instance) in digging a snow pit before skiing lift serviced off piste or looking at snow crystals on a card.. Unless you have done it loads of times it just wouldnt tell me anything and perhaps just give a false sense of security.
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And love to help out and answer questions and of course, read each other's snow reports.
And love to help out and answer questions and of course, read each other's snow reports.
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skimottaret, Hmm, There have been a few occasions where either a walking test and a hasty pit have proved to be a very accurate guide that has pointed to a 'no-go slope' when I have been out in the mountains.
The more you do these risk tests the better you get at them and also the more consistent you get at 'pulling at the snow pack' and hence applying the same pressure each time, Im not a great lover of using the shovel to pull on the pack as its hard to apply a similar force each time, I thinks its much better using the hands, this is something that the Canadians and the Scottish also prefer.
Avalanche reports are as they say, a grading of the risk based on past and current temps, weather and snow deposits that aim to provide a guidance in conjunction with your observations on the ground.
Im sure in the future, if you persist in testing slopes before you ski them, that you will come across a set of conditions that the tests provide a very clear result that points to a slope having a very high risk of avalanche.
Sometimes with courses they wont always run them on slopes that are avalanche prone for safety reasons. This in itself can be detrimental to learning about the results of any snow pack tests. To get a real grip you have to practice them on slopes that match the basic criteria for avalanche ie slope gradient and apsect etc.
Its great to learn the basics on a shallow slope, But even if this is done on a slope with the same aspect of a suspect slope it will bear no relation to the results you may get from testing the slope at the classic avalanche gradient. All real world tests Have to be done on the slope you think may be suspect, its no good testing on a 15 degree slope when your thinking of skiing the slope at 30 degrees plus.
Last year in Glen Coe I was lowered through a cornice on to a steep slope to check its stability, there were no obvious pointers to past avalanche, ie debris, snowballs etc, I dug a hasty pit and it pointed to a 2ft depth of windslab lightly bonded that slipped very easily, I can say that from that observation the slope was a definate no go, it was breaking way as I did a simple trench by walking.
If anyone really want to do some real testing and see slopes that avalanche I would highly recommend giving SAIS a call and organise spending a day or more out with the guys and gals that go out and test the slopes and write the avalanche reports, you will need to be self sufficient and preferably have ski touring kit as they mainly ski in and out of the test areas.
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Just to add to the above, something that is worth while making or getting hold of is a simple card that has a gradient scale on it, you hold this agains the slope and it will indicate the gradient.
Im sure a lot of you may be surprised at how low the gradients are of the majority of lift served off-piste runs that you may be skiing and as a result you may find that they are not at the classic slope angles for avalanche, hence snow pits and other tests providing inconclusive results.
This is a great piece of kit...
http://www.mcofs.org.uk/avalex-card.asp
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You know it makes sense.
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mark handford, again great advice and well said, i am very much in the "the more i learn, the more i realise how little I know" camp when it comes to off piste skiing 
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Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
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| skimottaret wrote: |
| ... experience seems to be the best tool... |
there is a certain amount of truth in this - part of the idea when digging a pit is to get a "history" of the snowpack. if you have been skiing the same area all season, you will have seen this first hand
the usefulness of pits is an interesting topic in itself... or maybe I should say can of worms
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Poster: A snowHead
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usefulness of pits is an interesting topic in itself
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go on get out the can opener....
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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Of course, the old problem of dangerous slopes is that the same slopes that provide the bigest avalanche danger also generally have the bigest deposits of snow which we most enjoy skiing, and, being north facing in the majority of cases, tend to remain as undegraded powder the longest.
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Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
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total geek that i am i just bought an inclinometer  couldnt resist for a fiver on ebay...
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mark handford, Equally using simple geometry and a pair of ski poles you can make a pretty good estimation of 30 and 45 degree slope angles; 30 degrees being widely accepted as the start of the regular 'danger zone' for avalanches...
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Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
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You'll need to Register first of course.
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| Quote: |
| Plant one pole in the snow and use the other pole as a marker, |
A simple tip I got shown for measuring slope angle is with a compass.
Turn it on side - and the needle will be horizontal.
Then use the degree measurement dial to estimate slope angle.
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| the usefulness of pits is an interesting topic in itself... or maybe I should say can of worms |
Snow (test) pits are a very useful learning exercise.
But.... if you feel the need to dig one in the field before skiing a slope then I would argue you probably know the answer already (i.e stay away!)
Test pits only tell you about that particular spot on the mountain.
Even in the space of 100 metres the snow pack will usually change *lots* (due to wind distribution, aspect, altitude, previous skier traffic etc).
And you shouldn't ever be on foot, digging a pit, on an avalanche prone slope ? 
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| Haggis_Trap wrote: |
| Quote: |
| Plant one pole in the snow and use the other pole as a marker, |
A simple tip I got shown for measuring slope angle is with a compass.
Turn it on side - and the needle will be horizontal.
Then use the degree measurement dial to estimate slope angle.
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| Turn it on side - and the needle will be horizontal. |
I pressume you mean the 'orienteering arrow' thats the one on the base? as there is no way that the magnetic needle will always be horizontal.
But yes, you can use a compass to measure angle of slope line the long edge up with the slope and wind the baseplate untill the orienteering arrow is pointing skywards at 90 degrees to the horizontal ( do this by eye) then read off the dergrees on the outside of the compass.
Really your using the compass as a protractor.
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Haggis_Trap has saved me some typing on the drawbacks of pits. I don't think they are *bad* but you just need to be very careful in interpreting the results
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You'll get to see more forums and be part of the best ski club on the net.
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[quote="Haggis_Trap"]
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| And you shouldn't ever be on foot, digging a pit, on an avalanche prone slope ? |
Why not? There are plenty of walkers, climbers etc who approach on foot and may wish to see how bad the slope may be before they make a plan of safe travel either across the suspect slope or by avoiding it.
We have all walked across frozen pools as kids, testing the ice as we go the same applies to snow slopes, even if the snowpack conditions change on different parts of the slope there is nothing to stop you evaluating as you move across and then retracing your steps if you don't like what you find.
Obviously there are big differences in how the slope may be used by a walker or climber opposed to a skier, walkers will try to cross the slope at the highest point possible where as skiers may wish to ski down the slope.
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| if you feel the need to dig one in the field before skiing a slope then I would argue you probably know the answer already (i.e stay away!) |
Hmm, isn't the point of testing the snowpack the whole point? because you don't know! What if the slope is at the correct gradient, what if there are no visual clues to recent avalanche activity, what if there has been no overnight snow, what if, what if what if,,,, you just test the snowpack and make the best descision based on logical information based on the knowledge you have, or your Avalex card or your Nivotest, or if you have none of theses, or you have no experience you then 'just stay away'.
Saying that if you feel the need to dig a pit, then you allready know the answer,, is twaddle, imo.
To assume anything in the mountains is not good...assumption is the mother of all stuff ups.
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you might argue that digging a pit just provides you with a whole new set of assumptions (eg that the snowpack where you ski is similar to the snowpack where you have dug your pit)
skimottaret, see what I mean about can of worms?
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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mark handford, Definitely, the AVEX cards are great to have in a pocket/ top of pack.
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And love to help out and answer questions and of course, read each other's snow reports.
And love to help out and answer questions and of course, read each other's snow reports.
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| Arno wrote: |
you might argue that digging a pit just provides you with a whole new set of assumptions (eg that the snowpack where you ski is similar to the snowpack where you have dug your pit)
skimottaret, see what I mean about can of worms? |
Ahhgggg, Arno, assumptions this word will only ever lead to problems, they could be small problems and easy to bear, or they could be very big problems leading to feeling like you have the world on your shoulders!
Yes, the snow pit gives the conditions of where it is dug, it does however give you very usefull information that can then be applied, with logic, to all the other information around you as well as the weather forecast and the avalanche report. Armed with this knowledge you can them make a more accurate prediction of whether the slope is good or bad.
The more information you have, the more knowledge you have the better you will be at making a sound descision.
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| mark handford wrote: |
| I pressume you mean the 'orienteering arrow' thats the one on the base? |
yup - or the inclinometer if your compass has one.
| mark handford wrote: |
Why not? |
A snow pit doesnt tell you anything other than the condition of the snow pack where your digging.
So if I think a slope may slide then the last thing I want to being doing is standing on the critical section digging a hole. To get all the information you actually need would require digging several snow pits at different aspects / altitudes and places.
Additionally.... You would only ever actually stop, take your skis off, and dig a test pit at spot you already consider to be safe. This is common sense - but means the test pit can only provide limited information.
In summary - snow pit's can give you a little useful information.
But they dont paint the whole picture.
And they dont give a simple answer like 'go' or 'dont go'.
Last edited by So if you're just off somewhere snowy come back and post a snow report of your own and we'll all love you very much  on Mon 1-12-08 19:13; edited 1 time in total
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You know it makes sense.
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mark handford, I think this takes us back to our own personal methods of assessing risk and approach to risk generally (and maybe Haggis Trap comments about if you need to dig a pit you probably already know the answer)
I am quite happy to admit my abilities are quite limited on this front and, knowing that, I err on the side of caution. I start with the assumption that I will not ski a slope and then see what factors (if any) will convince me it is safe. For example, the following factors would make me pretty confident about a slope:
- hasn't snowed in a week
- not warm enough for wet slides
- less than 30 degrees
- S facing
- no terrain traps
(OK that's pretty straightforward)
So, the only circumstances in which I would find myself digging a pit would be if other factors didn't give me an obvious answer, in which case I probably shouldn't ski it. Really, I'm just applying something akin to the 3x3 analysis. Maybe this means I don't ski stuff which I could, but I can live with that
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Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
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Poster: A snowHead
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| GordonFreeman wrote: |
How steep is the swiss wall out of interest. I've done it but don't know the exact angle.
So, when you say it could slough, that is wet or dry snow?
Why could it not have slabs? |
I'd guess around 45 degrees for the first 100m. Certainly not much more.
Slough = loose snow "avalanche" released by the skier. If you watch hairy, scary extreme skiing films you see it all the time. Dry snow.
The Swiss Wall could easily have slabs. Except that it's east facing and the prevailing wind direction is from the south-west, which is reinforced by a valley that the wind funnels up. It's also an itinerary and avalanche controlled. So, whilst not impossible, it's improbable.
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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There are no black runs with sections over 38º in Europe and almost none over 35º. Anything with a pitch over about 30º is a black. (If I remember rightly the wall used to be a black before they started reclassifying many alpine Blacks)
I would have thought 35º would be about right, though I don't know.
If nobody knows perhaps someone has a 1:25,000 map and could count contours for the top section and work it out (roughly).
Obviously being an itinerary the pisteurs would take very great care to only open it when they were sure they had got rid of any wind slab - otherwise they woul be legally responsible for any accident.
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Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
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| snowball wrote: |
| There are no black runs with sections over 38º in Europe and almost none over 35º. |
So the flypaper at Glencoe is no longer in Europe ?
Short but steep - about 40 degrees on the fall-line.
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You need to Login to know who's really who.
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| mark handford wrote: |
offpisteskiing, Yea thats what I use as a rough guide, Plant one pole in the snow and use the other pole as a marker, if both handles touch its 45 degrees, if they meet at the half way point on the pole planted in the snow the slope is 30 degrees
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Actually half-way would be 26.5º But it is quite hard to get the vertical and horizontal accurate anyway.
Last edited by You need to Login to know who's really who. on Tue 2-12-08 11:07; edited 1 time in total
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Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
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Haggis_Trap, you have a point.
But has it actually been measured? If not it would be fun to try. I have a tiny spirit level which does angles. (I have taken it skiing but whenever I might have wanted to measure an angle I was having too much fun skiing)
 click.
Just put a ski or pole on the slope - put the mini spirit level on it and twist the dial to get it horizontal. Read off the angle.
Last edited by Anyway, snowHeads is much more fun if you do. on Tue 2-12-08 11:10; edited 5 times in total
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Sorry - I am just being cheeky...
Getting back on topic, & as you said in your original post.
Most steep black pistes are circa 30 to 35 degrees
A red run is maybe 20 / 25 degrees.
And a blue / green run will be circa 15 / 20 degrees.
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Someone told me that Milton Keynes slope is about 15º (17º the top 1/3). I'll check it next time I go.
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snowball, there's an easier way to tell 30 degrees with 2 poles - involving an equilateral triangle and complementary angles (reminds me of a joke); but I'll let folks work this out for themselves...
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You'll get to see more forums and be part of the best ski club on the net.
You'll get to see more forums and be part of the best ski club on the net.
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Yes, I was wondering about drawing it and puting it on here.
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snowball, 15, 13, 11 i was told.. will have to get my half an equilateral triangle set of poles on that one tonight.
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FAQ
