Avalanche

 

Avalanche risk is best reduced by avoiding it.

 

 

Every year many people lose their lives to avalanches.

To avoid avalanche risk, it is absolutely necessary to be well-equipped, well-educated and to access current information about the area for your planned trip.  No compromise.

 

Avalanche - Introduction to Hiking - Hiking With Barry

 

Sources commonly used for this area are:

 

There are several informative, official websites to consult.

Wherever there is a combination of hills or mountains with accumulating snow cover, there will be sources of information to evaluate avalanche risk. 

Please seek them out before entering the terrain.  Other hikers, people on snowshoes, snowboarders or skiers will share information about weather and snow condition dynamics.  Speak with them. 

Park Rangers are an invaluable source of current information.  Log your trip so people know your location and plan.  Check in on return so no-one initiates an expensive search unnecessarily. 

Please regard this as serious business and enjoy great, safe fun.

 

Avalanche, Mountain safety

Avalanche Slopes in Kananaskis Country

 

 

 

Imagine the first snow fall of the year.  The transition in the mountains is magnificent and the mountain tops receive more snow than we do down below.  The temperature is colder up there and snow accumulates more often and more rapidly.  New snow on rugged, steep, rocky terrain is understandably more stable than snow on a steep, smooth grassy slope.  It only stands to reason. Over time the snow layers build up, one layer on top of another. 

A mild spell with some upper altitude rain freezes the surface to a crust of slippery ice.  New snow accumulates on top. 

At the same time the mass is increasing to thousands of tons.  Additionally the snow underneath is aging and changing into unstable, amalgamated ice crystals.  Your footstep in a vulnerable location may be the trigger which breaks the surface tension. 

The trigger can be gravity or warmth or wind creating pressure on the surface or a combination of some or all.  Once that mass begins to move, it can achieve speeds near 200 km/hr (125 mph) very quickly.  If you are near the top of the slide you may be able to grab onto a tree or anything that will arrest momentum.  If you are below the slide you may have enough time to get out of the path of the slide.  If you are caught in the avalanche, and ill-equipped, you may be able to push with your legs and 'swim' with your arms to stay on or close to the surface. 

If you are encompassed by snow you are covering your face to keep breathing passages unplugged and you may be dependent on your fully trained partners to find you, dig you out, and save your life.  As soon as conditions are deemed safe, and there is no apparent risk of further events, they will be running an expanding grid directly below your last seen location and adjusting their directional beacons to zero in on your location so they can commence digging.  

In avalanche terrain, we hike or snowshoe with significant distances between us, never in a group.  We use two-way radios for communication.  Everyone is on high alert.  Communication is high.  When avalanche safety training was taken many years ago at the Calgary Outdoor Centre we were given two minutes to locate and extricate a buried backpack containing a transmitting beacon.

 

Avalanche - Introduction to Hiking - Hiking With Barry   Avalanche - Introduction to Hiking - Hiking With Barry Avalanche - Introduction to Hiking - Hiking With Barry Avalanche - Introduction to Hiking - Hiking With Barry Avalanche - Introduction to Hiking - Hiking With Barry Avalanche - Introduction to Hiking - Hiking With Barry

 

Avoid entering avalanche zones alone unless you are absolutely certain the risk is negligible or non-existent.  Even then, senses should be on high alert.  Even if the avalanche risk is rated as 'Low', it is best to avoid entering an avalanche zone alone or improperly equipped.

 

The Canadian Avalanche Danger Descriptions are:

 

  • Green - Low - Avalanches unlikely - Travel is generally safe.
  • Yellow - Moderate - Avalanches possible - Caution required on steeper or risky terrain
  • Orange - Considerable - Avalanches probable - high caution in steeper terrain.
  • Red - High - Avalanches likely - Travel in avalanche terrain is not recommended.
  • Red with Black Border - Extreme - Avalanches certain - Avoid travel and stay well away from avalanche path run-outs.

 

 

Avalanche risk changes unpredictably and dynamically,   Following are a few things worthy of vigilant, diligent, attention.

 

  • On the way in, look for signs of recent avalanche activity.  Indicators can be slanted or broken trees, trees with no bottom branches and clumps or mounds of snow.

 

Be aware of:

 

  • The sound the snow is making under your feet.  If you hear a thump beneath your feet it may be an indication of compromised and unreliable terrain.
  • Heavy snowfall in proximity to your location and particularly at higher altitudes.
  • Rain
  • The direction and intensity of wind.  Pay attention to snow drift high up on ridges or near summits.  Wind pushing on a slope creates 'weight' on accumulated snow.
  • An increase in temperature.
  • The size of cornices above and the potential result of path of their collapse.
  • Choose sensible paths around bowls.  Select lower grades of ascent.  Choose slopes with trees, instead of open ground, whenever possible.
  • When travelling in avalanche terrain I travel in a minimum group of three.  More is better and safer.

 

Each person will be carrying:

 

  • An avalanche beacon (transceiver) with fresh batteries and fully checked prior to trip beginning.  It is a graphic range and direction finder.  More than one in receive mode can fairly rapidly locate another buried in transmit mode.
  • A probe. It is like a long, collapsible tent pole.  The probe can be used for evaluating snow condition or for locating a person buried in snow.
  • A shovel.  Lightweight and collapsible versions pack better.  The shovel can be used to build a snow shelter or to extricate an avalanche victim.
  • The group should carry standard pack contents including a first aid and emergency kit as well as collectively more warm clothing than normally necessary.

 

This gear is of very limited or no value if everyone does not know how to us it.

 

Prior to setting foot into avalanche territory, take an Avalanche Awareness and/or Safety Course.  These are usually a day-long classroom session followed by an essential field trip with a seasoned professional who will teach you how to use the gear. 

Locally an excellent program is available at the University of Calgary.  Check this out at the Calgary Outdoor Centre.  

The cornice deserves special mention.  A cornice is a shelf of drifting snow created by wind blowing over a ridge.  The unsupported snow shelf expands as snow events accumulate.  Look up and know where they are. 

Equally important is to know what they are above.  If a cornice breaks loose on a warming day, or because it has surpassed critical mass, it may fall on an unstable slope of snow below and trigger an avalanche.  If you are walking on top of a ridge, you must not walk on a cornice.  You can use your probe to determine if there is stable ground underneath.  If you are uncertain or if it looks or 'feels' wrong, you must be roped or you can choose to turn back or find an alternate route.

About five years ago, two very experienced and well-known, local mountain climbers completed a mixed ice and rock climb south of Canmore, Alberta.  At the end of the climb they chose to return to their car on a ridge.  They inadvertently walked on, or near, a cornice which broke free.  One climber was seriously injured and the other died.  It was a reminder to all of us that even the most experienced are vulnerable. 

There is no guarantee. In the summer of 2010, two hikers were attempting a traverse over the summit of Mount Kidd in Kananaskis Country.  There was unconfirmed conjecture they may have been attempting something beyond their level of experience.  The beautiful, sunny day turned instantly tragic when one hiker stepped onto a cornice to have a picture taken near the summit with a view of the magnificent Kananaskis Valley in the background.  The cornice broke free into a 3,000 ft, free fall.  It took several days to recover the body.  There are cornices resident on mountains year round.  They are particularly unstable in summer when the rock underneath is wet and warming.

A recommended book is Backcountry Avalanche Awareness by Bruce Jamieson.  I review this book every year before entering the snowbound wilderness.  You can check it out at Canadian Avalanche Centre resources. 

Inflation collars and vests are saving lives in this area.  They are coming down in cost and gaining wider acceptance and use.  This is very serious business.

 

 

 

 

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