JUDGE
THE STABILITY OF THE SNOW
-look for evidence of other avalanches. (Most
Important)
-Look for collapsing snow. Listen for a "whomp"
sound. This sound means that snow is extremely unsafe. Move
out of the area immediately, and stay off of steep slopes.
-Look for cracks in snow. The longer the
crack the more dangerous the snow.
-Watch for rapid changes in weather. (rapid
increase of new or wind blown snow, rapid warming, melting,
or rain on new snow).
JUDGING TERRAIN FOR AVALANCHE RISK
-Anchors. Things such as trees and rocks
help hold snow in place, but to be effective, they must be thick
and strong. Tree age and population density are examlpes
of anchor effectiveness. A sparcely populated stand of saplings,
would be much less successful in anchoring snow than a mature
densely populated stand of trees.
-Steepness. Most avalanches occur, most
frequently on slopes between 35 and 45 degrees. Slopes
less than 30 degrees seldom produce avalanches and slopes steeper than
about 50 degrees slough so often that they tend not to build
up into slabs. Unfortunately, 35-40 degree slopes are the
most popular for skiing.
-Aspect with respect to wind and sun. Slopes
that have been covered with wind blown snow are more dangerous,
while slopes that have been eroded by the wind, are usually
more stable. Slopes that are shaded, especially during colder
months are more likely to produce dry-slab avalanches, while
sunny slopes during warming months are more likely to produce
wet slab avalanches.
-Consequences. Survival depends on the size
of the avalanche, and where one is caught. A large avalanche
could trap an individual in a deep crevasse under many feet
of snow. One could even be pushed over a cliff and then be buried
from there. Smaller avalanches, although just as deadly, may
not involve as much snow and force, and are more likely to be
survived.
TESTING FOR AVALANCHE PROBABILITY
-Use test slopes. Test small slopes on
foot, skis, snowboard, or snowmobile to see how the snow responds.
If it is questionable, stay off larger slopes.
-Cornice tests. Find a refrigerator-sized
cornice and tumble it down the slope. Hint: ALWAYS wear
a belay rope and use a snow saw or thin avalanche cord to cut
the cornice. This this should only be attempted by experienced
individuals.
-Dig snow pits in representative slopes. To
do this test, you will need to complete a multi day class on
avalanche safety. This show only be attempted by experienced
individuals.
SAFE TRAVEL TECHNIQUES
-Have an escape route planned. It always
better to have a plan beforehand, and to expect that something
will happen, rather than not being aware that it may happen.
-If it looks like questionable terrain, find a safer
route. Take advantage of the safety of ridges, thick
trees and slopes with safer consequences. Always remember, you can,
in most cases go back the way you came if a safe route is an
issue.
-Travel One at a time. Someone should always
remain in a safe place for rescue purposes while members of
their group are on the dangerous part of the slope. Always
keep visual and voice contact with everyone in your party, but
do not occcupy the slope all at once.With large groups, split
them in half.
-Use slope cuts. Keep your speed up and cut
across the starting zone, so that if the slope slides,
your momentum can carry you off the moving slab into safer terrain.
You can do this on skis, snowboards or on snowmobiles.
-Watch out for cornices (overhangs caused by blown
snow that have little to no solid foundation). These pieces
of unsteady ground break off easily, and should be avoided by
taking a wide path around. NEVER, NEVER walk out to the edge
of a drop-off without first checking it out. Many people have
died this way.
-If there's no other choice, go underground.
Snow caves or crevasses provide adequate shelter for short term
survival during bad snow storms or avalanches. You may be uncomfortable
but you will be alive.
WHAT TO DO IF YOU GET CAUGHT IN AN AVALANCHE
GETTING OFF THE SNOW SLAB This needs to be done quickly
and is hard to do. If descending on skis or snowboard, head
straight down the slope. This will increase speed. You then
much angle off to either side (preferably the side with the
closest stable snow) and move off the slab. If you're ascending
there's really not much you can do. If you're close enough
to the crown, you can try running uphill to get off the slab,
or running off to the side. If you are on a snowmobile, increase
the power to move you to safety. If you're headed uphill,
continue to move uphill. If you are crossing a slope, continue
across to safe snow. If you're headed downhill, the only thing
that you can dois to try and outrun the avalanche. Sometimes
it works, but usually it doesn't.
If you can't get off of the snow slab, try grabbing a tree.
This needs to be done very quickly because avalanches will
pick up speed. The trees that were once your saving grace,
will become deadly devices. After about 4 seconds they can
easily be traveling at 40 miles per hour, and you can imagine
what a tree feels like at 40 mph. (Almost a third of avalanche
victims die from trauma from hitting trees and rocks on the
way down.)
If you are not able to escape or grab onto a tree, you
need to swim hardbefore you start to sink.
As the avalanche finally slows down and just before it comes
to rest,
-Try
and clear an air space in front of your mouth to help delay
the formation of an ice mask, which hinders breathing even
more than what it already is.
-Try to push a hand upward to attempt to have
a visual marker for rescuers. You may not know which
way is up, but take your best guess.
-After the avalanche comes to a stop, the debris
will instantly set up like concrete. So any actions you
take must occur BEFORE it comes to a stop. Unless you
are very near the surface or have a hand sticking up out of
the snow, it's almost impossible to dig yourself out of
an avalanche.
AVALANCHE
RESCUES
-Watch them to see where they end up
-DO NOT GO FOR HELP. Victims may have only
a few minutes of life, and if you leave, they will probably
be dead when you return. Spend a half hour to an hour trying
to find them first. Also, by going for help, you could endanger
people making an attempt to provide rescue assistance by loosening
more unstable snow.
-Is it safe to try a rescue? Usually it's
safe, but if the individual is buried in a place with multiple
avalanche starting zones looming above and weather conditions
are questionable (i.e. it's snowing hard or blowing hard
or there's rapid melting), then there may be a good chance of another
avalanche coming down on top of the search area. It's a hard
call. If you think it's too dangerous then it probably
is. If it's too dangerous then you should go for help.
It's a job for professionals.
-Find a safe route to the avalanche debris.
Often you can descend down the avalanche path or come up from the
bottom onto the debris.
- If the victim is wearing a
beacon, turn yours to receive and make SURE everyone in
your party is turned to receive.
- Go fast and cover a lot of ground.
- Look carefully for clues, hands
sticking out of the snow, snowmobiles, skies, gloves.
- In most snowmobile burials,
the victim is usually just uphill of their snowmobile.
Source: www.avalanche.org |
