Quantitative Risk Analysis of Riding in Avalanche Terrain

[Hugh Conway]

Because you don't think much of AIARE, or because you took such a good course way back in 1998 from ... who?

Norm Wilson? He doesn't compare to your voluminous experience though.

At least you could get a map.

[PNWbrit]

Norm Wilson? He doesn't compare to your voluminous experience though.

I had $20 on you having gone the route of one of those remote learning Ecourses offered out of the east coast.

[icelanticskier]

All I saved was a passing mention in an article mainly on the solo climber fatality

isn't that enough to get an idea? i heard more detail from a regular client. knowing how that line loads up on the regular, there is a safe way to ski it, and an unsafe way to ski it. a coupla feet the wrong way up in the area of the roll over can spell disaster. the "island of safety is pretty much always a few hundred feet down on skiers left off to the side and in the brushy area. to ski to that area it makes the most sense to ski the skiers left side so as to not cross under the suspect wind loaded skiers right face. knowing the guide and how he skis, he is pretty light on his feet (skis) where most folks being guided or skiers in general that don't know any better will ski down into a line very heavy footed and will be more apt to penetrate deep into the dragons lair.

(And looks like no update to the guide's blog -- would have made for some interesting material!)

agreed.

rog

[Hugh Conway]

I had $20 on you having gone the route of one of those remote learning Ecourses offered out of the east coast.

and that's why you're a cunt.

[PNWbrit]

You haven't changed the batteries have you...?

Hint: I never really thought you'd done an email multiple choice quiz and frozen golf course field trip avy education.

[Jonathan S.]

Norm Wilson? He doesn't compare to your voluminous experience though.

At least you could get a map.

Okay, curiosity satisfied (and your prior point well-taken), thanks.
(However, I don't see why you need to add in a sarcastic ad hominem remark, especially when I've been agreeing with you now on almost everything.)

[Jonathan S.]

I had $20 on you having gone the route of one of those remote learning Ecourses offered out of the east coast.

There is no such course.
As for my own course format, we have a very full day in the fall, then in the winter we have a full day of touring, an evening session, and another full day of touring. On top of all that we have various "remote learning" assignments (maybe about 20-40 hours or so), which mainly take the form of old-fashioned reading and writing.

[Jonathan S.]

isn't that enough to get an idea?

Yes, and it matches up well with what I was told by another snow ranger.
I still that merits a bigger write-up though. (Well, your own write-up here is very instructive -- thanks! -- but it doesn't get the kind of exposure that a post would have received on the USFS website.)

[icelanticskier]

Yes, and it matches up well with what I was told by another snow ranger.
I still that merits a bigger write-up though. (Well, your own write-up here is very instructive -- thanks! -- but it doesn't get the kind of exposure that a post would have received on the USFS website.)

unfortunately much of a write up at all, especially on his own blog for his guiding service probably wouldn't be very good for business. an "oops" is pretty much all we get. 2nd hand

you should send your students out with me sometime jonathan. they'll never wanna go near avy terrain again!

i kid.

rog

[Jonathan S.]

you should send your students out with me sometime jonathan. they'll never wanna go near avy terrain again!

i kid.

rog

Well, we already had the opposite sequence, as I had have one of your regular touring partners (and your partner for the GoS avy) take the course with me the following season ... but I don't think there's any connection. (He had already taken Marc Chauvin's two-day course, and wanted to further his avy education, getting as many different perspectives as possible, which I find highly commendable.)

[icelanticskier]

and to think how much money i coulda saved those guys. never satisfied, heh

it's safe or it's not...........why further complicate the phenomenon?

rog

[the Cock]

If you know it so well Rog, why'd you get taken for a ride?

You do realize you've become a "tool" for avalanche course instructors?

Maybe the winky implies the above.

[icelanticskier]

If you know it so well Rog, why'd you get taken for a ride?

actually I did know it so well as right before skiing into the line I advised my partner to get his camera out in case the thing went. of course this was after I made a plan a/b/c with him in case it felt good/sketchy/ or avalanche! luckily I stuck to my plan of how I would ski/where i'd be it in case it went. managed to get up and out of the main gully feature enough to avoid the main (largest) terrain trap while staying in my partners line of site. he stayed put and eyes peeled the whole time as we discussed. twas our second run of the day. 1st run was bomber not very far away. thought I could get away with a run in more of the gut of the snowfield. I did get away with it, after a pretty hefty yet ultimately uneventful ride. now I know whats it's like to go through the spin cycle. would prefer to avoid it in the future tho

You do realize you've become a "tool" for avalanche course instructors?

I do. because I was more than willing to share in detail with pics of what happened that day so others can learn from the experience and to know that avalanche incidences happen here and not just out west, yurp...........

got anything else, cock?

rog

[Jonathan S.]

coming from someone that spends most of his days up high in winter I will tell you that you really should start spending at least a day or two above treeline in winter to really see what's up. the skiing/weather is a whole lot more forgiving than you or most ec bc users would think.

Much of the wintertime skiing on Mt Washington isn't really all that “Up High,” e.g., your avalanche was only about 1300' higher than the highest point I often ski from in . . . Massachusetts.

But as for me, during the current (at least for me) ski season, in the winter I skied at or above treeline on Mt Washington on seven days (once from the summit, once from 400' below the summit, twice from 800' below the summit, and three times just at treeline, i.e., usually incorrectly referred to on Mt Washington as “above treeline”).

Granted, that is only a trivially small % of this half-million-vert+ ski season, but that’s exactly my point: Mt Washington just doesn't offer many attractive wintertime options for me. With very rare and obscure exceptions, any skiable snow at or above treeline is wind-affected (regardless of whether we call it “powder”). Many different aspects are skiable, as shown in the spreadsheet I put together for my students, but even if they’re not in the lee of prevailing winds, then they’re typically cross-loaded.

Now when we go awhile without any new precip, and the windslabs lose all their energy, and with no persistent weak layers, that’s different. But otherwise, although mitigation measures are of course available for both route selection and micro terrain management, that’s more like Tremper’s middle option in his chart. I’ve been very impressed with the micro terrain management you previously pursued on a regular basis, but you also confirmed for me (albeit unintentionally) the slim safety margin for such tours.

This brings up a key point from Blase Reardon’s excellent ESAW presentation last fall: the backcountry snowpack does not provide a consistent environment with regular feedback, but rather its feedback is inconsistent and often fatal. Bruce Tremper uses the analogy of playing soccer in a minefield. In the context of his chart here, imagine automobile safety if we didn’t have a speedometer, couldn’t see that we were tailgating other cars until they started braking, had no idea if the pavement was clear or icy, etc. By way of analogy with avalanche safety, I suspect that most backcountry skiers are driving faster, tailgating more closely, and are on more slippery pavement than they realize.

For another activity in the chart, the epidemiological statistics provide a reasonable assessment of my risk for the plane I’m on now. Sure, this is during the daytime, with clear weather, an operator other than Crazy Clown Airlines, a captain other than Wi Tu Lo, and I actually read the safety card. For more active mitigation measures, I could use only those airports with the highest level of runway navigational aids, and maybe also research which plane models have the best safety records. But I doubt that’s going to change the risk all that much.

By contrast, the avalanche risk in backcountry skiing is whatever we make it. For a skier with absolutely no knowledge of avalanche safety who always sought out big steep lines with unconsolidated winter snow, I suspect the risk would be far higher than anything in the chart. Or for a hypothetically infallible skier who never ever made a mistake in stability assessment and terrain selection, the risk would be nearly zero (reflecting the nearly negligible possibility of some truly freak avalanche).

I think Tremper’s chart would serve as a better heuristic tool if only those two avalanche-related extremes were presented (and without the spurious precision of the detailed descriptions), emphasizing the self-determined nature of our position in the chart.

[icelanticskier]

nice explanation!!!^^^^^

by "up high" i meant avy terrain. not the summit cone, auto road, cog.

and typically our snow instabilities are VERY short lived compared to most other regions. and it's mostly of the new snow/slab variety. potentially dangerous deep persistent instabilities are quite rare. nice to not have to resort to meadowskipping much in winter.

i like tremper's pov

he and gordon taught me

rog

[skifishbum]

lets compare a # we don't actually know to some studies from the 1950's
then lets make it extra extreme and ASSUME somethin like there are people centerpunching 10 slopes on high danger days with no clue
Throw in a survey of experts that didn't even include Roj some references to unofishial surveys over coffee
and ya get.......

[userA]

reagan era scare tactics?
b

[Skihuckster]

And I'll add my 1500 word essay:

.
.
Aw fuck it

[icelanticskier]

Mt Washington just doesn't offer many attractive wintertime options for me. With very rare and obscure exceptions, any skiable snow at or above treeline is wind-affected (regardless of whether we call it “powder”). Many different aspects are skiable, but even if they’re not in the lee of prevailing winds, then they’re typically cross-loaded.

a majority of the only real alpine/above treeline/avy terrain in the east where you teach courses (inside and away from avy terrain) and you find it an unattractive wintertime option? weird.

you would have to spend more time up there (in winter) to seek out where the good skiing is on any given day. if you understand the weather, the wind, the precip, and how it all works together up there, you might find it's absolutely delightful. but you never truly know if you don't go. good snow is pretty much always there unless it rains then freezes with no new snow to follow. you ski a bunch in the pnw. truly you must have to deal with frozen up high to score good corn in the middle and mank down lower or for the exit at least. more often then not you can ski good snow on George from t2b in winter on the lee side of the hill. good edgeable quiet chalky snow much of the time with beautiful powder snow more often than you would think at any and all elevations depending on the day.

but i'm sure you would rather skin and lap wachusett or Berkshire east than play around in the range with the best most western like terrain in the east and practice what you preach in and around avy terrain in winter. and of course there's nothing wrong with that. you have a beautiful family, you want to make sure you make it home for yer daughters bed time, and you are an super awesome guy.

we can all read till we're blue in the face about avalanches, avalanche safety, the latest greatest gadgets, techniques, take courses, and stare at spreadsheets, BUT if yer not spending time in and around avy terrain when conditions are dynamic, you have no perspective on the matter, imo.

rog

[wra]

Mindless jabbering...
we can all read till we're blue in the face about avalanches(more jabbering), BUT if yer not spending time in and around avy terrain when conditions are dynamic, you have no perspective on the matter, imo.
roje

Maybe you can get with the quarter lapping bobble head, roje and take johny into the high country for a show and tell of how it's done. I mean...play the "sunny bowl-days after a storm" vid just prior so he's good and scared.

[icelanticskier]

and maybe you can come along, bob, and pick up a few pointers on how to link turns smoothly without looking like you have a tree branch shoved up yer ass

ugh the image of you skiing

rog

[wra]

Wull...uh...I'm not sure what linking turns has do to with quantitative risk analysis but...I make no claims on internet avalanche expertise, either.
Last avalanche class I took was in the mid eighties. They didn't teach um on the internet, then.

[CookieMonster]

These sorts of analyses almost never pan out because neither risk, nor risk acceptance, are static. Even if you had good statistics on backcountry skiers and ski days, it would be next-to-impossible to know how much risk they actually assumed. The fact is that centre-punching can be much safer than "playing it safe" if you're centre-punching well-settled snow compared to "playing it safe" when size 3 slides are running to valley bottom. Anyway, this shouldn't be construed as criticism of the analysis, but it's important to realise that you can patch holes in data only to a certain extent. Anything beyond that constitutes rank speculation, and should be disclaimed as such.

A good first step to getting real data would be to study a group of randomlyselected backcountry skiers for a few seasons. That might point in the direction of some real numbers.


Sent from my Paranoid Android using TGR forums.

[skifishbum]

I aint no expert but if your gonna attempt to compare apples to oranges 50 year old fruit aint gonna look, taste or feel anything like this years crop
didn't anybody stand up and point this out
or are they all in such awe of each others expertness that obvious glaring flaws in data are just accepted
I still got the # of peeps center punchin 10 slopes with no form of avvy awareness and prevention at 0
which is probably the same # of people who paid for and showed up for an avvy cert class and
didn't pass.
my surveys of turn earning skibums over doobies conforms this data

[icelanticskier]

Wull...uh...I'm not sure what linking turns has do to with quantitative risk analysis but...I make no claims on internet avalanche expertise, either.

still ugly. and still bitter after the avy club cut yer obz funding for being an angry ole curmudgeon a-hole some dozen years ago.

howz that shoulder, btw

rog