Avalanche Safety

Avalanche Safety

The Dolomite Mountains offer some of the best off-piste and backcountry skiing found anywhere in the world. To best enjoy these experiences, safety should be the number one priority for anyone venturing into the snowy backcountry. There are many inherent risks that come with partaking in such activities, from changing weather conditions to navigation to conditioning and skill level, but the risk of avalanche is one with the highest potential consequences. This is not to dissuade you from participating in the joy of seeking fresh turns on untracked snow, but to help make sure you enter these activities with a heightened awareness so you can enjoy the mountains in the winter – safely.

An avalanche is a rapid flow of snow, ice, and/or earth sliding quickly down a slope. Avalanches come in many forms and sizes, and may be triggered by either natural or human activity. This sliding snow has the potential to bury anything in its path, including trees, rocks, and people. Anyone who plans to spend time outdoors in the winter in mountainous areas such as the Dolomites should be aware of what avalanches are, what causes them, and how to assess the potential risk before heading out for a day of backcountry or off-piste skiing (skiing in areas that are not groomed or frequently traveled), or other outdoor activities where you may encounter slopes. Moreover, you should know how to avoid triggering an avalanche or skiing in high-risk terrain, and, worst-case scenario, know how to increase your odds of surviving one should it occur. 

There are a few important things to note about avalanches:

  • Avalanches are a byproduct of unstable snow, that can be triggered by natural or human forces
  • The elements that play the greatest role in avalanche risk are slope angle, orientation of the slope to the sun and wind, and temperature
  • Any time a skier goes off-piste there is a risk of an avalanche
  • Most people buried in avalanches have triggered the avalanches that buries them

In order to truly assess the risk potential or a given slope, many factors need to be taken into consideration. These can either be learned through specific avalanche training courses, skiing with an experienced avalanche certified guide, or a combination  of the two. 

In general, there are two types of avalanches:

Point release avalanches, also known as loose snow avalanches, form when a small amount of cohesionless snow begins to slide, and typically picks up more snow as they descend, fanning out like a triangle. While point release avalanches are usually small and involve only the surface of the snow, the stress of this movement can also trigger a larger and deeper slab avalanche

Slab avalanches occur when a slab of cohesive snow begins to slide as a unit before breaking up into smaller pieces. Slab avalanches may be soft or hard, wet or dry, and form unstable slabs that don’t stick well to the layer beneath, be it another layer of snow or the ground beneath. Slabs may be caused by a number of factors, ranging from wind loading, to fresh snow deposited atop a firm crust of snow, to rapid ground surface melting beneath the snow layer, to name a few.

In either case, the snow sliding may be heavy snow or powder, wet snow or dry. The thickness of the sliding snow can vary from just a few centimeters to 11 meters (35 feet) or more (although most human triggered avalanches are limited to 1.5 meters / 5 feet), and may slide atop the surface of existing snow, or all the way to the bottom layer, revealing the ground. Speeds range widely from 20 to 200 kilometers per hour (12 to 120 mph), and have been recorded as high as 350 kilometers per hour (217 mph).

The consistency of snow sliding - wet or dry - each carry their own inherent risks as well:

  • Powder-snow avalanches are particularly dangerous because of the speed with which they take place.  Additionally, powder-snow avalanches involve a dangerous mixture of snow and air, which can quickly asphyxiate anyone who happens to be in its path.
  • While wet-snow avalanches descend slowly, the snow is extremely dense and hardens quickly to a concrete-like consistency once it stops, making rescue of trapped skiers very difficult. 

Once you understand what avalanches are and how they slide, you must consider what to do to avoid causing or being trapped by one. There are various scales used to measure risk of avalanche, and most popular areas for off-piste skiing publish bulletins advisories and warnings to aid skiers in safe backcountry travel. Skiers and mountaineers should be well aware of these available precautions in order to avoid dangerous situations and prepare accordingly prior to heading out to hit the slopes.  Those who do ski off-piste should heed the following tips: 

 

  • Review the avalanche advisory for the region you plan to ski if one is available. Note that conditions can change daily, so don’t rely on yesterday’s bulletin for today’s tour!
  • Never ski alone.
  • Always let someone outside of your group know where you plan on skiing.
  • Carry and know how to use avalanche rescue equipment including an avalanche beacon, shovel, and probe pole. (An avalanche beacon is a transceiver device that transmits a signal to rescuers should you be caught in an avalanche, and receives a signal from other beacons that allows you to assist in a search for avalanche victims. Beacons are made by several companies including Tracker, Pieps, Ortovox, BCA, and ARVA.)
  • Choose your route with care: preferably undulating areas, slopes broken up by steep inclines and flatter or rolling sections, and areas that have dense timber.
  • Be careful where you stop; avoid lingering under large outcrops or on crests – these may be cornices that have the potential to break off.
  • Always be aware of the changing weather and fluctuations in temperature.
  • Don’t attempt off-piste skiing immediately after a heavy snowfall (80cm / 2.5', or less if the snow has drifted) – most avalanches occur within 48 hours of fresh snowfall or drifting snow.
  • Avoid overly steep terrain (>30°) if there is any potential avalanche hazard.
  • In the spring east- and north-facing slopes are safer (in the northern hemisphere), and skiing on the south and west-facing slopes should be avoided late in the day when the sun has warmed them and slab avalanches are likely.
  • Avoid crossing a slope in the middle; if you have t o cross a slope, cross as high as possible, and one at a time so you do not overload the slope and trigger a slide. If the slope does slide, only one person is exposed to danger at a time, and at least one person is available to help rescue them.
  • Treat all avalanche terrain as if it is ready to fail.

 

After taking all of the above precautions, should you still find yourself facing an avalanche it’s important to remember the following:

  • Assess the situation as quickly as possible.
  • Try to escape to one side while descending, rather than to try to outrun the avalanche.
  • If you are caught in the avalanche, do not panic.
  • If you are at the higher part of the mountain you should attempt to cling onto something, such as an exposed tree or bush.
  • If you cannot grab onto anything, try to ride atop the avalanche by swimming up hill through the snow.
  • Keep your mouth shut and do not breathe while the avalanche is moving you – if the snow is powdery use a scarf.

 

Should you become buried it is essential that you do the following immediately:

  • As soon as the avalanche stops, use your knees and fists to push away the snow as far as possible to try to dig yourself out or, at minimum, create a small cave with as large an air space as possible.
  • Try to rescue yourself – if you can get a hand or other body part above the surface of the snow, it will help your companions find you more quickly.
  • Remain calm and don’t waste energy and oxygen shouting – while you can hear people shouting above the snow, they cannot hear you under the snow.

It’s important to remember that even well-traveled areas are not completely safe from an avalanche, and anyone participating in activities on the mountain must use common sense and avalanche training and awareness to be safe.  Skiers should also be warned that just because they’ve skied a particular area before without incident does not mean it will be as safe every time they return, as each winter is different and conditions may have changed greatly even since the last run earlier in the day. It is also important to note that not all avalanches lead to fatalities, but to increase your chances of avoiding or surviving one, the above suggestions and tips should be taken into account by anyone planning to spend time on the mountain. Experienced skiers are typically at the greatest risk for encountering an avalanche because of their propensity to participate in off-piste skiing.  This article is not intended to discourage you from discovering the delights found in off-piste skiing, but to encourage you to do so safely. 

For more information on being safe in the backcountry in winter, check out our Enjoying the Mountains in Winter – Safely article.

IMPORTANT NOTE: This article is in no way intended to be a comprehensive resource regarding avalanche safety, but merely an tool to build awareness of the seriousness of participating in winter sports in mountainous terrain. Our hope is  that readers will choose safety by skiing with a knowledgeable guide, getting avalanche training, and wearing an avalanche beacon and knowing how to use it.

 

Check out our Winter Skiing and Snowshoeing Trips.