Glaciers are intricate things which should be
appreciated and in many ways
feared. Throughout the course of
modern
mountaineering many lives have been lost while trying to
traverse glaciers which are often found at the bases of mountains.
One noteable example is the death of
Jacques Batkin who died after a
creavesse fall on
Denali's Kahiltna Glacier while attempting
the first winter ascent of Denali.
A glacier is a large body of slowly moving ice. When a glacier moves
around a bend the outside ice will travel farther than the inside
of ice. This causes the ice to fracture apart, creating a crevasse.
Creavasses can be a few to hundreds of feet deep.
Some creavesses are apparent. They can be spotted and a new route can
be established around them. More often, though, a snow bridge will span
over the creavesse making it unapparent to a person on the glacier. Many
deaths and injuries occur when individuals step through a snow bridge
and plunge hundreds of feet to the bottom of the creavesse.
To combat the risk of falling teams of mountaineers will travel roped
together (this is called roped travel). Each member wears a harness and
ties themselve into the rope with a figure eight knot. Spacings of 10
to 30 meters are primarly used. When choosing a rope for glacier travel
it should be dry treated so that it resists soaking up water, getting
heavier, and freezing. Also, the gram per length of the rope is often a
big consideration on expeditions, therefore a 8.6 or 9mm
rope is often used.
If a member of the roped team falls through a snow bridge into a creavesse
the other members of the team must fall down to a prone position and try
to self arrest with their ice axes. It is hoped that the remaining
members will be able to arrest the fall of member(s) in the creavesse
before they are pulled in themselves.
After the fall is arrested trained techinque must take over. This is a
vital time, and for this purpose people are strongly advised to take
creavesse rescue courses before venturing out on a glacier.
Sometimes a fallen member might be just dagling and can jumar himself
up to the creavesse lip. But, often, the fall taken into the creavesse can
create injuries. This requires the other members of the team to be versed
in rope rescue technique.
Occasionally (some say insane) people choose to go solo across a
glacier. Some have been known to attach large aluminum X's to their
body so that if they fall in a creavesse the X will hold them from falling
through completely. A well written description of this can be found in
Into the Wild by Jon Krakauer. He says that after he had
pulled himself out of the creavesse he had fallen into with the X
apparatus he collapsed mid over and started dry heaving because his
body was in shock by how close he had came to dying.
You can attempt to self belay on a glacier with a deadman, but it's
overly hard and best saved until you've already summited Everest a few
times without oxygen and you need something more dangerous to get thrills.
Like most other things in mountaineering and climbing, if you value
living tommarow don't solo -- it's just not worth the risks.
On well traveled mountains such as Denali creavesses
might be marked with wands, allowing for pilots to land, and people
to generally scurry around. However, if you are in doubt you should always
rope up and have your ice axe ready for a self arrest.
If you approach a glacier from below be carefull venturing into the
ice caves which are sometimes formed. With the deep blues and
breathtaking ice shades one can easily be twisted around and confused.
Associated with ice caves, are waterflows which run under the glacier.
Much like a snow bridge it is possible to fall through the fragile
covering of such a waterflow and be sucked into rapidly moving water.
This water is of course cold, and your chances of survival
are minimal. The waterflow might seperate into a multitude of different
chutes, all of which are not big enough for your body and you will be
drowned. Puncture wounds often happen in waterflows. Your best bet
if you fall in such a waterflow is to try to keep your feet downflow, and
protect your head as much as possible. If you are roped you can attempt to
do a hand jumar back to your entry point if the current is calm enough and
you have not lost motor abilties from the cold water.
Another problem which arises from glaciers is ice fall. Probably one of
the most noteable ice falls is the Khumbu Ice Fall on Everest. This is
believed to be the most dangerous areas to traverse if you are approaching
Everest from the West. The Khumbu Ice Fall occurs because
the glacier above falls almost a vertical half mile into the Khumbu
Valley below. One must traverse the ice fall consisting of dangerous
seracs with aluminum latters and bridges. Throughout, other large
seracs overhang the route and threaten to fall on you. Generally a
guide company is elected to place a series of latters and bridges through
the ice fall.
So, remember, a glacier is more than just a piece of ice. It's a dangerous
piece of ice, and that's what makes it worth traveling on.