Lawinenbulletin

An essential tool for off-piste skiing and ski touring is the avalanche report, also known as the avalanche bulletin. This has changed considerably over time. Not only does it appear more frequently - once or twice a day - but its spatial resolution has also become more detailed and precise. With the advance of artificial intelligence and the integration of model-based forecasts, new perspectives are opening up in avalanche warning.

Fortunately, this season got off to a very snowy start and provided a good foundation. It stayed that way until shortly before Christmas. The so-called Christmas thaw materialised just in time for Christmas.

The Bavarian Avalanche Warning Service started the season this winter with a new website, which is real news. After all, a good presentation here can lead to greater safety by ensuring that more people read and understand the bulletin.

Since this winter, the SLF has categorised the danger levels with intermediate levels. What do you think? The Swiss Avalanche Warning Service would like to know, and is asking the target group of ski tourers and freeriders to complete a short questionnaire.

What experienced skiers could more or less reliably glean from the text of the bulletin is now put into concrete figures. From this season onwards, the SLF will use three intermediate levels for the avalanche danger levels moderate, considerable, large and very large. For level 3, for example, a 3, 3= or 3+ is given in addition to the "whole" level (3, considerable). 3- is closer to 2, 3= is "neutral" and 3+ is closer to 4.

The SLF observers monitor and assess the current situation in their area and transmit the observations to the SLF (WSL Institute for Snow and Avalanche Research SLF). The data collected forms part of the basis for the daily avalanche bulletin. I was allowed to accompany Reto, one of the observers, for a day and look over his shoulder.

There are repeated reports of an old snow problem, but exactly what this means can be confusing. First of all, you should know that an avalanche problem (old, new, drifting, wet and sliding snow problem) is not a hazard pattern, but can consist of different hazard patterns. An avalanche problem describes the type of avalanche and its mechanisms, whereas a hazard pattern describes the responsible weak layers and their processes.

A recent SLF study uses GPS tracks from the Skitourenguru.ch database to correlate avalanche accidents with the number of accident-free ascents. This makes it possible to calculate which danger levels and terrain characteristics are particularly risky. There are some interesting differences to the reduction factors known from the Munter reduction method.

There will be a brief spell of sunshine today (Wednesday), followed by more snow on the northern slopes of the Alps. The weekend is also expected to be very wintry with snow down to low altitudes.

Arnold Studeregger is part of the avalanche warning service at ZAMG in Styria. We spoke to him about the development of the Styrian LWD, the biggest innovations and his favorite snow profile

In his recently completed dissertation, SLF avalanche forecaster Frank Techel investigated how well avalanche bulletins reflect the actual danger situation and whether they are consistent across different regions and areas of responsibility of individual warning services. In this interview, he explains more about his work and his unusual career path.

The SLF issued its first avalanche bulletin on December 21, 1945. Since then, avalanche risk forecasting has developed significantly. However, despite all the technical advances, specialist knowledge and the assessment of experts are still required today.