Hi Christa and Anna,
You’re both right that mountains and glaciers can be
dangerous places and definitely require some knowledge, skills, and gear in
order to safely climb and travel across them. I’ll first explain what a glacier
is, and then tell you about what makes them dangerous and how to work around
these dangers.
 |
| My teammate crossing a crevasse on Everest. |
A glacier is kind of like a big frozen river. Glaciers form
in cold places—at the poles or in the mountains—where more snow falls than
melts over the course of a year. This means that over many years the snow
builds up and compacts itself into a big block of ice.
Glaciers may seem frozen in place but
they actually do move, just at a much slower pace than you or I do, so it would
be hard for us to notice unless we sat and watched for months or years. When a
glacier forms on a mountain it will flow downhill, like a river. Crevasses,
which are gaps in the glacier where the ice has split, form because of
disruptions to the glacier’s flow. Crevasses are the biggest danger to be aware
of if you want to survive a glacier.
Crevasses form when different parts of
the glacier move at different speeds, causing it to break. Sometime the top and
bottom move at different speeds because the bottom is slowed down from friction
against the ground, whereas the top is not. The same idea behind why you would
be able to quickly glide across a frozen lake, but not a rocky path.
 |
| Roped up for glacial travel on Mt Vinson. Left to right: me, Doug, Victor. |
Most of the time we try to go around them, or over them on sturdy snow bridges, but crevasses are dangerous to
mountaineers because it’s possible to fall in them—and it’s hard to get
yourself or your teammate back out unless you’ve come prepared. Mountaineers
typically travel across glaciers in a group all roped up together. That way if
one person falls in, the rest of the team can anchor themselves into the ice to
catch the fallen person on the rope. Once the team has built a solid anchor,
the person in the crevasse can use what are called prusik knots to climb up the
rope and out of the crevasse.
So here are some of the supplies that
you would need:
--A
rope
--A
harness, which you wear to attach yourself to the rope
--An ice-ax and
crampons—sharps points that would help anchor yourself into the ice and catch
your teammate in case he falls in a crevasse
--Ice screws and
pickets to build an anchor in the ice to take the fallen persons weight
--Cord to tie prussic
knots to use to climb the rope up out of a crevasse in case you fall in
I hope that helps, good luck with your
speech!
Samantha
