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SAIS Avalanche reports

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 MG 25 Feb 2010
When was the last time a level 5 report was issued by SAIS. Today's are all level 4 and I am trying to imagine how more avalanche prone conditions would be possible in Scotland.
 Andy Nisbet 25 Feb 2010
In reply to MG:

I think level 5 involves a threat to habitation etc, which would be hard to get in Scotland
 Milesy 25 Feb 2010
From Glencoe today.

http://1.bp.blogspot.com/_Dy4xDYd7B1w/S4abjW97NOI/AAAAAAAAAGo/0A9K7trhhfE/s...

This surface hoar is a ticking time bomb! That slab is scaring me!
 Simon Caldwell 25 Feb 2010
In reply to MG:
1st November 2002
http://www.sais.gov.uk/archive/02-03/2002.10.31.txt
which was probably a test!

There have been a few though:
http://tinyurl.com/yauerp2
 stevez 25 Feb 2010
In reply to MG:

They were forecasting Category 5 on Wednesday on certain aspects in the Northern Cairngorms.
OP MG 25 Feb 2010
In reply to stevez: Doesn't appear that way in the archive.

OP MG 25 Feb 2010
In reply to Toreador: Not for some time then!
 Fat Bumbly2 25 Feb 2010
In reply to Milesy: A very scary photo.
 Mark Bull 25 Feb 2010
In reply to MG:

> (In reply to Toreador) Not for some time then!

I suspect not since the SAIS adopted the European Avalanche Danger Scale (not sure when that was though). Level 5 indicates "Many large natural avalanches" where large is defined as "Length >1000 m, Mass >10,000 m3", which is pretty much impossible in Scotland, I suppose.

See http://www.slf.ch/lawineninfo/zusatzinfos/interpretationshilfe/interpretati... for details.

I'm sure it isn't obvious to most folk that "High" is in effect top of the scale in Scotland, and that "Considerable" is really level 3 out of 4 rather than 3 out of 5.



 James Edwards 25 Feb 2010
In reply to Mark Bull:
I think that you are mixing up Level 5 with Catagory 5. The level is the devestation that an avalanche has caused and the size of it (after the event). The Catagory 5 is the chance (likelyhood) of one happening. In the case of Cat 5 that is spontanious without exterior assistance, i.e. human trigger.
James e
 Mark Bull 25 Feb 2010
In reply to James Edwards:

> I think that you are mixing up Level 5 with Catagory 5. The level is the devestation that an avalanche has caused and the size of it (after the event). The Catagory 5 is the chance (likelyhood) of one happening. In the case of Cat 5 that is spontanious without exterior assistance, i.e. human trigger.

I don't think I am, at least not in the terminology used in the document I linked above, nor in the report on the 15th European Avalanche Warning Services (EAWS) Conference at http://www.avalanches.org/uploads/media/EAWS_Conference_Innsbruck_en.pdf
The SAIS do not appear to use the term "Category" any more, either.

The above link contains the following remarks:

"Kjetil Brattlien’s lecture entitled “Is the Avalanche Danger Scale dangerous?” unleashed a
stimulating debate on the names/titles of danger levels at the end of the session. The
discussion was given additional fuel by Grant Stratham’s remarks about the “North American
Danger Level Project”. Stratham, too, called general attention to the well known problems
with regard to the name/title for Danger Level 3.
Kjetil’s proposal:
Re-naming the danger levels for Levels 3 and above should underscore the peril in the
perception of the average person. The definitions of the respective danger levels remain
unchanged.
Proposal:
Level 3: “considerable” -> “high” / ...
Level 4: “high” -> “very high” / ...
Level 5: “very high” -> “extreme” "


depthhoar 25 Feb 2010
In reply to MG:
Just for the record, a ‘Very High’ hazard of avalanche category has never been used in Scotland since the inception of the SAIS (or Scottish Avalanche Project, as it was called when it began in 1988). There were probably only a few occasions prior to its beginning when conditions may have warranted a ‘Very High’, but these are now of historical interest only (The Loss of Gaick – twice! – when a substantial building was overwhelmed and demolished by avalanches 100 years, to the day, apart).

All countries with seasonal snow cover interpret hazard categories according to local conditions. In Europe, the Swiss, in particular, require a scale with a pretty serious top end because they have densely populated villages in high Alpine locations that can be wiped out by avalanches (many villages destroyed in the 1950s). Same applies to the Austrians (most recently, Galtur), the French (eg. Montroc) and the Italians (eg. Cervinia).

In Scotland, our problem is one of recreational visitors (climbers, hill-walkers, ski-tourers) and the massive frequentation of these hill-goers during the winter months. We tend to extend the scale upwards. For instance, in Canada I was a little taken aback, when I was on training and assessment there, at how the Canadians viewed the size and frequency of their avalanches in relation to the hazard category. Avalanche frequency/size and stability that I would happily have called Considerable if I were working in Scotland were unanimously designated as Moderate.

The North Americans have more and bigger avalanches; we have fewer but way more visitors to the mountains. (Scotland had more avalanche fatalties –12 - in the winter of ’94-’95 than Canada). My guess is that we unconsciously slew the scale upwards to take account of this high level of frequentation and our terrain/topography. Most of our avalanche victims don’t get fully buried. Many suffer trauma injuries ‘in transit’ down the mountain by getting banged in to rock, boulders etc. Complete burial is more common (sometimes with trauma) in Alpine nations. Bottom line is that Scottish avalanches don’t have to be big to kill you. Get caught by a small slab, lose your footing and take a 300m tumble down a crag will have much the same ultimate outcome as a full burial under a couple of metres of avalanche debris.

Today there was some discussion as to whether or not to put out a ‘Very High’ category for tomorrow (Friday) on my patch. At least one other avalanche forecaster out the 5 SAIS areas has discussed this possibility with the SAIS Co-ordinator within the past day or so. Instability is certainly widespread at the moment (a ‘Very High’ pre-condition) and not just confined to a few aspects. The avalanches are also likely to be big ones with long run-outs (another ‘Very High’ pre-condition). My own issues are with the exposure of a low-level and popular approach path to big avalanches from above. This happened a couple of years ago when a big one passed through open and mature woodland, took out a few trees (root-ball and all) and crossed the path. It was decided today that the ‘High’ category covered this contingency but that our use of the ‘Very High’ category would be reviewed as conditions develop.

Hope this helps.
 AlH 25 Feb 2010
In reply to depthhoar: Thanks for the insight.
Al
 Lucy Wallace 25 Feb 2010
In reply to depthhoar:
Very interesting! Thankyou. Sometimes I quite fancy the life of an SAIS recorder, but right now I don't envy you having to go out and poke around in that stuff!
 pec 25 Feb 2010
In reply to MG: I do remember wondering at the time SAIS adopted the European system whether it was entirely relevant to Scottish conditions. The fact the the highest category has (almost?) never been used suggests that perhaps it isn't?
Unless everybody is aware that cat 4 is in effect the highest level then there is the possibility that some people may not consider the level of risk to be as serious as it actually is.

Can anybody shed any light on why it was adopted? There may well be good justification for it but just for the sake of trans European harmonisation doesn't seem like the best reason if its not the most appropriate system.
 Ron Walker 25 Feb 2010
In reply to depthhoar:

It's interesting you say that the Cat 5 has never been used because as far as I can remember it certainly has. It was around the time that the Cat 3 moderate became a Cat 3 considerable. I seem to remember an unfortunate avalanche incident around that time too. But then again maybe my memory is worse than I thought!!!
Cheers Ron
 Ron Walker 25 Feb 2010
In reply to pec:

> The fact the the highest category has (almost?) never been used suggests that perhaps it isn't?

My thoughts too...
depthhoar 25 Feb 2010
In reply to Ron Walker:
Hi Ron,
The SAIS in effect had a 6 point scale for a while, splitting the Considerable category in to 'minus' and 'plus'. The public weren't supposed to know about this as it was to do with our internal housekeeping/accounting procedures when we were using the Nearest-Neighbour/NXD/NXDLog/Cornice (had more makeover name changes than Jordan/Katie Price/whatever-her-name-is-now, and about as user-friendly) avalanche forecasting software. So, technically, in those days 'High' would have been a Cat.5, with 'Very High' a nominal Cat.6. Confused? I was!

We seem to be moving away from the divvying up of the Considerable category, which I think will help make it plainer and easier to understand for all concerned.

I'm still pretty sure we haven't used a 'proper' Very High category before but my cranial hard drive is totally shot as well.

All the best.
 Ron Walker 26 Feb 2010
In reply to depthhoar:

Unfortunately I'm still working in DOS 2.1 on a 486 Pentium using a WTF/log/1998/LOYER/TURD software thinking 3 is moderate on a sliding scale of 1 to 5 or else I'm talking gibberish!!

Cheers Ron
 wercat 26 Feb 2010
In reply to Andy Nisbet:
"I think level 5 involves a threat to habitation "

We must have had that in Weardale in the 70s then - Family house near us engulfed by snow that burst in and filled one or two rooms(Crawleyside Bank above Stanhope) - they were winched away by helicopter (Wessex?) as the roads were all blocked (alt c 1100ft asl)
 Andy Nisbet 26 Feb 2010
In reply to depthhoar:

> We seem to be moving away from the divvying up of the Considerable category, which I think will help make it plainer and easier to understand for all concerned.
>

Personally I think it's "dumbing down", as it seems to be "considerable" most of the time and while it doesn't mislead, it doesn't actually tell you much. I know you're supposed to read the detail, but actually the plus and minus makes sense. Considerable (localised) and Considerable would be better than minus and plus


 Davy Gunn 26 Feb 2010
In reply to depthhoar:
I was with an observer in Glencoe once who put out a 5 due to the two of us being in a Corrie and being avalanched an all sides but the way we got out. Blyth bollocked him as no cat 5 applied in Scotland and removed it!

While even in the new system this is probably technically correct, I would worry that it pushes the "considerable" to more days, as in cat 3 and encourages folk to get risk fatigue (it's always cat 3 so lets go) and to ignore the once in 15 year storms that come onto what is more like a continental snowpack, with it's associated long lived potential for victim triggered release long after the storm is over.

The pro's who are under pressure to take clients out might do so and back off, or make a good safe travel choice, but the punter watching without insight see's it as ok creating a Heuristic Trap. A smattering of black dots once in 15 years might make folk sit up and think of the example they are setting. It's a purely semantic argument. "Back in the Day" glencoe School of winter mountaineering saw the Clachaig bar as an essential training aid on days like these. The punters used comment that if these guys were not going out,then neither were they!
 CurlyStevo 26 Feb 2010
In reply to Andy Nisbet:
"Considerable (localised) and Considerable would be better than minus and plus"

isn't that what the small circles on the new forecast are for?
 Simon Caldwell 26 Feb 2010
In reply to depthhoar:
> Just for the record, a ‘Very High’ hazard of avalanche category has never been used in Scotland since the inception of the SAIS

Are you sure?

http://www.sais.gov.uk/archive/93-94/94.03.16.txt
http://www.sais.gov.uk/archive/93-94/94.03.17.txt
and there are more.
 oor wullie 26 Feb 2010
depthhoar 26 Feb 2010
In reply to Toreador:
Oops, quite right. I stand corrected!
 Simon Caldwell 26 Feb 2010
In reply to depthhoar:
I'm surprised you can't remember, it was only 16 years ago

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