SNOW PITS... good or good for nothing?

[LeeLau]

Stupid CAC site has many dead links

Tent Ridge K-country in the Canadian Rockies. Your basic 30 degree unsupported planar slope. 3 skiers involved. Were digging a pit on that slope

http://www.clubtread.com/sforum/topi...TOPIC_ID=24657

[ACH]

Good thread.

http://utahavalanchecenter.org/avala...eshoe-mountain

That was an interest report.
Hope "A" had a full recovery from the incident.

[ill-advised strategy]

There is no avy forecasting in my area, so I often (though not always) dig, but it's just a piece in the overall evaluation. Weather patterns and familiarity with the terrain and conditions play a part.

wildland fire tangent:
Isn't it a little like spinning a weather?...it's definitely not a bad thing to do, but it's usually not a surprise unless you just arrived somewhere; and it probably shouldn't be the single focus for a particular go/no-go decision. It's going to be part of a due diligence process in big organized structures like DOT and ski area management for legal purposes, and the specialists at the avy center are happy to get field obs to keep the forecasting sharp...but when you're out there on your own...meh...I'm probably not going to be calling obs in every hour from my 2 man single tree fire in the wilderness; same as when you're up on some piece of terrain on a regular basis and you pretty much know how things have set up.

[skifishbum]

dug one full and prob a good 5 haisties a day on our week in bc haities told me almost as much as diggin & shovel whompin
dug quite a few the last 3 in the wasatch don't base go no gos on em as much as general snow geekery
kno plenty of more savvy peeps than i who never fully quantify much as someone aptly pointed out in the other thread
reached the point of spatial varibility meh these days
as always group dynamics if your partners are into it you'll do more

[Meadow Skipper]

wildland fire tangent:
Isn't it a little like spinning a weather?...it's definitely not a bad thing to do, but it's usually not a surprise unless you just arrived somewhere; and it probably shouldn't be the single focus for a particular go/no-go decision. It's going to be part of a due diligence process in big organized structures like DOT and ski area management for legal purposes, and the specialists at the avy center are happy to get field obs to keep the forecasting sharp...but when you're out there on your own...meh...I'm probably not going to be calling obs in every hour from my 2 man single tree fire in the wilderness; same as when you're up on some piece of terrain on a regular basis and you pretty much know how things have set up.

Exactly. IMO there are a lot of parallels between wildland fire and travel in avy country.

With a little adjustment, a number of these concepts are valid for avy country travel:
http://www.fs.fed.us/fire/safety/10_18/10_18.html

[lpkdz]

A respected and experienced mentor I ski with says "If I need to dig a pit, I shouldn't be skiing the slope". I still dig occasionally just for the learning, never to decide on if I'm going to ski a slope. I'm not good enough at the interpretation to be willing to make calls based on that information, and just stick to mellow terrain. I live in the Wasatch, and we have great resources through UAC, so I usually have a pretty solid idea of whats going on here and what to expect. Granted the bulk of my touring has been the past 3 seasons, which have been unsafe in general. I suppose if things appeared safer I'd be more interested in digging pits as a reason to refute skiing a certain area (as mentioned throughout this thread). This season I don't feel like I know enough to poke the bear in high avalanche conditions and take big risks.

Any opinions on the "If I need to dig a pit, I shouldn't ski the slope" ideology?

[summit]

Any opinions on the "If I need to dig a pit, I shouldn't ski the slope" ideology?

As I've said, don't dig a pit for a reason to go. Look for changes in the snow, reasons to say no, and to reinforce what you already know.

Hey... that rhymes...

[Hacksaw]

As I've said, don't dig a pit for a reason to go. Look for changes in the snow, reasons to say no, and to reinforce what you already know.

I agree...

[bodywhomper]

i often ski outside the bounds of a forecasted area, though the area is similar to the adjacent forecasted zone. people mentioning not making go/no-go decisions from pits; i have absolutely made no-go decisions and backed off an area based on a pit (i.e. agreeing with the above 2 posts). examples include coming across unexpected/anticipated snow structure weaknesses and poor stability tests; or encountering a wind slab while ascending a slope w/o observed winds loading the slope....

[simplypow]

Great thread, and I don't think anyone will ever suffer from snow pit analysis. I also like giving it more weight in the overall decision making processes that lead to "no" and less weight in a decision making event that leads to "yes".

[skiSilent_skiDeep]

thread revival

solid info.

[johngenx]

This is a good thread - pits are indeed one source of info that must be used in conjunction with the other stuff. We went out on a day of Low/Low/Low but the slope we liked felt a little slabby - setting off my spidey senses. It took only a few minutes to isolate a column and when I cut the back, the top slab literally popped out at me. It was a valuable lesson to the novices in the group - the more info you have the better. We found another aspect, dug into it, things were 180 degrees different in terms of results and we had some fun. Just used the pits to reinforce the other factors influencing our decisions.

One thing I've seen is people digging pits on an aspect and then skiing a different aspect - moving during their day - not seeming to understand that slope aspect is a critical decision point.

[TG]

Spatial variability within a whole bunch of closely executed pits/rutschblocks by Campbell/Jamieson

good luck if you dig a pit or two in the RB 6's and then ski 20 yards over in the 2's

always in my mind when thinking about what a pit means

or what I can get out of an obs posted online where the ECT score is noted to a very precise level of detail, but the location is plus or minus 100-10000 yards. Something super "precise" like "9300ft NE aspect".

It often seems like an exercise in demonstrating the poster's proficiency in pit digging and test result recording and buzzword knowledge, as if that technical mastery was enough voodoo to keep you safe.

[SchralphMacchio]

Funny to see this thread bump.

Lately Doug Chabot has been trying to keep things simple and encouraging digging if for no reason other than to do an ECT to rule out a terrain choice. I was taught not to do a blind ECT without doing layer ID first (to make sure you know your interface of concern), but Chabot seems to be saying, just go for it, use it when all your other signs say you're good to go:
http://www.mtavalanche.com/blog/put-your-shovel-snow

He continues to emphasize this point in these other blog posts:
http://www.mtavalanche.com/blog/huma...rs-and-digging
http://www.mtavalanche.com/blog/anot...gazine-article

I have a lot of thoughts on the shoveling topic today, as we are looking at very localized persistent weak layers in our forecast area that have been observed in many areas, not ever observed in other zones, and destroyed completely in some but not all locations. Now these PWLs are about to sit underneath 5-6' deep slabs. With these conditions the conservative call is to rule out north facing terrain unless presence of the PWL can be ruled out completely.

With a problem with this much locational variability, digging just one or two pits in a zone without a large scale of pre-existing data, and not finding the layers would still be considered taking a big gamble for many ... but in reality the practice of digging to reveal "no go" may still subconsciously translate into a "go" call for these types of variable and unresponsive persistent slabs. High uncertainty is the name of the game here.

This kind of problem also somewhat makes a case for using an SP1 in heavily traveled zones (more for the urban forecast areas or guided operations) before weak interfaces and layers get buried too deeply, to take quick snapshots in a zone and see that a specific interface simply doesn't exist in 100% of the samples taken in that zone.

[Hacksaw]

As a mentor of mine likes to say, "If you don't dig you don't know."

[Trapp]

A respected and experienced mentor I ski with says "If I need to dig a pit, I shouldn't be skiing the slope".

but in reality the practice of digging to reveal "no go" may still subconsciously translate into a "go" call for these types of variable and unresponsive persistent slabs.

I tend to agree with the former. If I think a slope is suspect, why dig for more reason not to ski. Why not just move on to a different aspect, elevation, etc.