The Avalanche Review, VOL. 17, NO. 3, JANUARY 1999
Copyright © All Rights Reserved; AAA
Wasatch Powderbird Guides Snowbird Ski Patrol
Avalanche
Hazard Forecasting is Simple!
Every avalanche field
worker is a forecaster. Whether deciding to ski a slope with a group of clients,
open a highway or ski run with or without control work, or change a backcountry
forecast from "considerable" to "moderate," a forecaster must seek answers to
three simple questions:
Could the terrain produce
avalanches?
Are avalanches likely?
What are the likely
consequences of those avalanches?
*****
But Avalanche Hazard Forecasting
is Complicated!
Answering even three
simple questions can be terribly complicated if the forecaster attempts to do
so in a purely logical, linear manner. For example, even a reasonably simple
decision-making algorithm might include hundreds of steps. The algorithm would
get longer and more complicated as a forecaster's experience increased!
*****
The Merging of Theory
and Practice
For the Zen Forecaster,
"theory" and "practice" don't have to be merged, because they are already intricately
enmeshed in a whole called "forecasting".
The Zen Forecaster does
not base decisions solely on the analysis of scientifically gathered data, but
gathers as much data as possible. He reads and listens and learns as much as
possible about the scientific study of avalanches, but does not discount folklore
and anecdote as valuable forecasting resources. He makes observations and gathers
as much information as possible from the forecasts and observations of others.
The Zen Forecaster seeks enlightenment; that is, he seeks to comprehend the
true nature of the avalanche hazard. His forecast is a feeling that comes to
him based on all of the theory he has learned, information gathered in practice,
and on his lifetime experience with avalanches.
Spend time with an old
heli-guide, veteran ski patroller, long-time highway avalanche worker, or grizzled
on-snow researcher, and the way you hear snow and avalanches discussed will
be different than in a classroom. Ask one of these experts whether it's safe
to cross a slope, and you'll usually get an answer like, "It feels okay to me",
or, "We'd better not, something doesn't feel right". Does she go all the way
through a complicated algorithm? Certainly not. The question is posed, she stops
thinking of other things and the answer comes to her. It feels safe, or it doesn't.
Where does the feeling come from? From the answers to the three simple questions.
The Three
Simple Questions
The three simple questions
are not to be answered "yes or no", but are used to develop feelings and perceptions
of hazard. The answers are represented here by three circular graphs.
Could the
terrain produce avalanches?
The avalanche field
worker will develop a feel for the answer to this by subconsciously asking himself
three other questions: "Have I seen or learned of any avalanches on this terrain?",
"Is this terrain similar to anyplace else where I've seen or heard of avalanches?",
and "Do I see other clues that indicate this may be avalanche terrain?".
Are avalanches
likely?
The answer to this lies
in the forecaster's feeling for the instability in the snowpack, and in her
feeling for the number of avalanche triggers available, both "natural" and "human-caused".
Avalanches are more likely when the level of instability in the snowpack is
greater, and when there are more triggers available.
The feeling for instability
comes from an infinite number of sources (to name a few: the forecaster's most
recent observations of weather, snowpack, and avalanche activity; observations
and reports from others; ski and explosive tests... ). Some of these sources
are difficult to explain scientifically. A veteran (or rookie) ski patroller
may suddenly get an uncomfortable feeling while in avalanche terrain, decide
to test a slope, and witness a large avalanche. Other times, when "measurable"
factors indicate instability, the snow "doesn't feel avalanchy".
|
What are the
likely consequences of those avalanches? Would the likely avalanches
hurt anyone? Would they damage property? Will they reach the highway,
railroad, village, or ski run? Are there people there? Are they wearing
transceivers? Will they be deeply buried, or carried over cliffs or through
the forest? Trying to answer these questions, and all of the others like
them, could take hours when that time isn't available. Again, the forecaster
gets a feeling about the likely consequences of any likely avalanches,
and acts accordingly. |
![]() |
The Zen Forecaster: Seeking
to Comprehend the True Nature of the Avalanche Hazard
Obstacles to Zen Forecasting
The Obstacle of
Ego:
letting ones perception of how he is viewed by others block his access to a
forecast.
A guide may be concerned
that her rich clients won't return if she appears to be too conservative. A
state highway forecaster who is the "new guy in town" may feel that he needs
to remind the locals that he's the one with the keys to the highway gate. The
person behind the voice on the recorded avalanche hotline may feel compelled
to use the first person so much that it says more about the forecaster than
the forecast. Or a ski patroller may be more concerned with sounding cool on
the radio than with what is actually happening under her feet.
These are all human
feelings, valid to the forecasters who are feeling them. But they don't help
a forecaster get a feeling for the answers to the Three Simple Questions.
The Obstacle of Focus:
letting
one's ability to feel the whole of the forecast be compromised by looking too
closely at one factor.
A long-time mountaineer
and ski patroller carefully measures and examines the wall of a snow pit, and
declares to his rookie partners, "This pit tells me that this slope won't slide".
Then he tests the slope with an air blast (two pounds of explosives suspended
on a bamboo pole), and the entire snowpack on the slope ends up on the ski run
below. Had he focused solely on the snow pit data, which he may have misinterpreted
(did misinterpret?), the slide may have occurred while the run was open. Another
forecaster says, "If it snows fifteen centimeters by midnight, the road will
close". It snows 15cm by 10:00 PM. By midnight, the sky is clear and the temperature
has dropped ten degrees Celsius. Does the road still close?
The forecaster who
gazes at her computer screen without looking outside, and the ski patroller
who uses explosive testing without paying attention to the previous night's
weather data are blocked by the same obstacle. They are focusing on only a small
part of a very big picture.
(This is not to say
that grossly obvious factors should be weighted equally with more subtle ones.
For example, if widespread natural avalanches are the only indicators of instability,
that's really all that is needed to say that avalanches are likely and to give
a good indication of the probable consequences. But continuing to look at other
factors may give an indication of when the level of hazard may change, and to
what level.)
The Obstacle of
Inattention:
letting one's attention
be drawn away from the forecast by internal or external distractions and pressures.
An avalanche guru
heads out the ridge to run a hand charge route. With his mind on a problem at
home, he steps out onto a hard slab and is carried down through a steep, rocky
chute, narrowly escaping serious injury. Another avalanche worker; intimidated
by his much faster route partner, neglects a pocket of wind slab. Fortunately(?),
it is another ski patroller who is caught in the slide, rather than a member
of the public.
In these and many
other instances, forecasters have their abilities to feel the forecast blocked
by distractions, particularly by powerful emotions. A forecaster who recognizes
when she is distracted is more able to put the distractions aside, or to ask
for help from others when she is not able to do so (see The Obstacle of Ego,
above).
The Training of
the Zen Forecaster
Apprentices Learn
From Masters, Masters Learn From Apprentices.
It is very difficult,
and can be dangerous to one's self and others, to attempt to become an effective
avalanche forecaster without ever spending time with a master. Perhaps less
evident is the idea that one can never truly become a master without teaching
others. By guiding others in their quest for the true nature of the forecast,
the master herself moves closer to enlightenment.
Mastering Zen Forecasting
is Complicated, but Mastering Zen Forecasting is Simple.
The master helps
his apprentices to access all of the knowledge and theory of avalanches that
they can digest. He shares his library, his anecdotes, his databases. He guides
his apprentices whenever possible to the next bit of pertinent information.
He helps his apprentices to quickly and thoroughly become expert at technical
skills (skiing, searching with transceivers, reading of weather instruments,
etc.). He seeks awareness of where he and his apprentices are in the five stages
of learning: unconscious incompetence, conscious incompetence, conscious competence,
unconscious competence, and conscious/unconscious competence).
The master offers
encouragement generously, reprimands gently, and shares the spotlight so that
her apprentices can avoid the obstacle of ego. She bypasses the obstacle of
focus by pointing it out, and by sharing her view of the big picture. And she
helps herself avoid distraction by reminding others of the obstacle of inattention.
Above all, the master
and his apprentices seek the true nature of the forecast by continually asking
the three simple questions:
Could the terrain produce
avalanches?
Are avalanches
likely?
What are the
likely consequences of those avalanches?
Bibliography
Atwater,
Montgomery G The Avalanche
Hunters
Philadelphia, Macrae
Smith Company, 1968
Fraser, Colin Avalanches
and Snow Safety, New York,
Charles Scribner's Sons,
1978
Fredston, Jill, and
Doug Fesler Snow
Sense
Anchorage, Alaska Mountain
Safety Center, 1994
La Chapelle, E.R. ABC
of
Avalanche
Safety Seattle,
The Mountaineers,1961
McClung, David and Peter
Schaerer The Avalanche
Handbook Seattle,
The Mountaineers'
1993
National Ski Patrol,
Judy Over, Education Director
Training Patrollers
Effectively Colorado,
National
Ski Patrol System,
Inc.,1995
Perla, Ronald 1. and
M.Martinelli, Jr. Avalanche
Handbook, USDA
# 489, Washington,
D.C., U.S.
Department of Agriculture,
1975
St.Ruth, Richard and
Diana Simple Guide
to Zen
Buddhism, England, Global
Books, LTD, 1998
Suzuki, D.T. Manual
of
Zen
Buddhism, New
York,
Grove Press, 1960
Suzuki, D.T. An Introduction
to Zen Buddhism New
York, Grove Press, 1964
Williams, Knox The Snowy
Torrents: Avalanche
Accidents in
the United States 1967-71,
Wyoming,
Teton Bookshop Publishing
Company, 1975
Acknowledgments
Masters, Mentors, and
Other Suspects
Thanks and credit are
due the many people whose words
and actions have contributed to the ideas expressed here. They have been
the author's coworkers,
teachers, res
cuers, and friends. They may not remember contributing, since many of the conversations
took place long ago, and/or were lubricated by blaster's fluid. All are, or
were, avalanche forecasters. They are, in alphabetical order: Jean Bellin, John
Collins, Jimmy Collinson, Bob Cushman, Denis Etienne, Larry Fields, Michel Felisaz,
Liam Fitzgerald, Daniel Howlett, Tom Kimbrough, Daniel Lagarde, Jim Mott, Mark
Mueller, Chris Philips, Bernard Ravanel, Joe Royer, Bob Sayer, Wes Schimmelpfennig,
Peter Schory, Greg Smith, Chris Stetham, Darwon Stoneman, Randy Trover, Christian
Vallet, Mike Weigele, Onno Weirenga, and all of the members of the Snowbird
Ski Patrol and Wasatch Powderbird Guides.
The Avalanche Review, VOL. 17, NO. 3, JANUARY 1999
Copyright © All Rights Reserved; AAA