Avalanche Reporting
Andy P under a crown wall
triggered by explosives
Photo by Paul Canning
After two well-publicised avalanche incidents in Austria and the USA, the UK press has been providing some debatable info.
Time for a few hard facts.
An incident in Lech involving the prince Johan Friso started it all off. What seems clear is that 2 skiers were off piste on a category 4 day in Vorarlberg when one of them was buried by a medium size slide. He is still unconscious in hospital.
In a second incident, 3 skiers died in an avalanche at Stevens Pass near Seattle.
In particular, some elements of the press have suggested a link between the high levels of snowfall and the increase in accidents. However, let’s look at the fatality report so far :
| Year | Fatalities in France | Fatalities in Switzerland |
| 2010 to 2011 | 17 | 9 |
| 2011 to 2012 | 4 | 12 |
So we see a marked drop in France despite record snowfalls. In Switzerland the death count is up, but looking at the map of those incidents on the excellent SLF website, most of these deaths took place in the east and south of the country, the area with the lowest snowfall.
My own observations show that the least stable snow this season has been in the Dolomites where , according to a local mountain guide, they have the lowest levels of snow for 15-20 years.
Why would it be that that less snow would lead to more avalanches ?
With a combination of shallow snow and cold weather, there is a temperature gradient in the snowpack which leads to the formation of sugary snow near the ground known as depth hoar. This forms a weak layer in the snowpack which can persist, sometimes right the way through the season. It is this phenomenon which contributed to the well publicised accident in Seattle recently.
So why are avalanche deaths in Austria up on last year ?
One possible theory is that snow levels last year were so low that participation levels were affected. In other words, there were fewer people skiing so, all other things being equal, there were fewer accidents.
But a headline like “avalanche accidents increase following record numbers of people skiing off piste” might sound a bit too simplistic…
Sources:
Association Nationale pour l’Etude de la Neige et des Avalanches
WSL Institute for Snow and Avalanche Research SLF