(click here for NZ
Weather & Avalanche
Geoff Wayatt - MountainRec., Member: Canadian Avalanche
Winter Avalanche/Spring Ice
caves in Shovel Flat photo
New Developments in Search &
Rescue Eqt/IKAR -video link
Avalanche Rescue Airbag -
Sno-Quiz: How many different
Snow Flakes are there? Answer below.
Recommended Winter Blog site:
The Utah Avalanche Center, run by Bruce Tremper,
is a great source of current avalanche information and
discussion. Check out their
Air-Bag survival statistics. The bags are effective tools, but
the survival statistics used by various sources overstate their
Extract from Blog by Bruce Tremper.
"My pet peeve with this issue is that people who argue about the numbers
often leave the most important part out of the discussion--terrain. If
you get caught in un-survivable terrain then, guess what, you won’t
survive no matter what kind of rescue gear you use. There have been a
number of prominent accidents in which the victim with a deployed airbag
died because he was either strained through thick trees and rocks,
deposited in a terrain trap, buried deeply or went over a cliff. In
zero-tolerance-for-error terrain, airbags don’t work, beacons don’t
work, Avalungs don’t work. Nothing works. Save your money, buy a life
insurance policy and a beacon or RECCO so rescuers don’t have to spend
all night probing.
So at least for me, unless I’m 99.9 percent certain that the
slope won’t slide, then I don’t go to un-survivable terrain. If I’m
going to spend the money and carry the extra weight of an avalanche
airbag pack, I want to ride in terrain where it has a chance to make a
difference. In other words, choose terrain with no obstacles, no
terrain traps or sharp transitions and avoid large avalanche paths.
The other part of the discussion is the often-overlooked issue of
what we call “risk homeostasis.” Each gizmo we buy to increase our
safety usually cause us to increase our level of risk at the same time.
For instance, when we added seat belts and airbags to cars, yes
fatalities decreased, but it also allowed us to drive faster, farther,
crazier and talk on our mobile phones at the same time. So safety
measures usually work but not nearly as well as we would hope because
people just increase their risk (and “utility”) at the same time. In
avalanche airbag case, we will also get more powder, more fun, and more
risk in the bargain.
Ignore the 97% number and the 3% number. My best guess is that
avalanche airbag packs will probably save a little more than half of
those who would have otherwise have died in an avalanche. They will
never save all of them because 1 out of 4 will likely die from trauma of
hitting trees and rocks on the way down and an additional 1 out of 4
will probably end up in a terrain trap (deep burial), buried by a
secondary avalanche or caught in an avalanche that does not travel far
enough for the inverse segregation process to work (larger objects rise
to the surface).
In addition, people will increase their exposure to risk because
of the perception of increased safety, which will cancel out some, but
not all, of the effectiveness of avalanche airbags.
As usual, our choice of terrain is far more important than rescue
gear. Un-survivable terrain will always be un-survivable. In terrain
with few obstacles, terrain traps, sharp transitions and smaller paths,
avalanche airbags have the potential to save significantly more than
half of those who would have otherwise died. And that sounds pretty
good to me."
I would love to hear your comments: http://utahavalanchecenter.org/email-bruce-tremper
Postcard from the Avalanche Edge
2012 Ski Touring tips by GW
TOURING TIPS from Geoff Wayatt
Lengthen the life of Adjustable Ski Poles
When collapsing them for carrying, don’t tighten the locking mechanism
and you’ll double it’s life expectancy
Wind some Duct tape around the ski pole, so it’s handy for use if your
skin glue fails to stick to your skis.
Ever encountered the irritating repetition of squeaky ski binding when
climbing a long arduous slope?
Solution: Silence them with a quick squirt of suncreme.
Red Sky at Night – a Ski Tourers delight?
This denotes no cloud and clear skies out on the horizon.
For anticipating an even longer “fine weather window” watch for a purple
hue progressively and slowly deepening in colour.
Luna-tic weather predictions based on the Moon/tidal effect?
Weather Forecast Tip: Ignore Ken Ring’s predictions and beliefs. They
aren’t backed by proven science.
Why? In brief - Water is 700 times more dense than air, therefore the
Moon’s effect will be 700 times less on our air mass and weather
Where? Go to the NZ Met Service Rural Outlook for a brief 7 day
forecast for cloud, precipitation, temperatures and wind (all on 1 page)
Weather Clearance? Using your barometer for wx prediction
You get a clearance after a storm. How long will it last? If your
barometer does not rise above 1,000hp (sea level) then the clearance may
not last very long. The just past front may be quickly followed by
another front and storm. Only time for a shorten tour and turn for home
while visibility lasts?
Current stats indicate that a group with a female in the party is less
likely to ignore obvious avalanche danger signs and avalanche
Take note: All 20 - 30yr old single males who are the statistically the
high risk group.
Newly available Avalanche Airbags limit your chances of deep burial and
greatly improve survival rates (at a cost of $1,000 +) In a few years
they will be as common as Avalanche Transceivers.
Cold Feet? Loosen boots, reduce sock constriction, put a hat on.
Cold Hands? Do rapid “aero-plane propeller” arm swings to increase blood
Cold Body? Bulk up with down jacket or food.
Remember Bergman’s Rule! Animal size increase as latitude increases.
i.e. Polar bears and Emperor penguins.
Carry dog biscuits in your pocket and you might be a higher priority
find for an alpine search dog?
Avalanche Transceivers & Cell Phones
Cell phone electronics can interfere with Transceiver searches, so turn
New Safety Technology – AirBags
Balloon News: The latest and most innovative safety item since the
transceiver is now available:
The Avalanche AirBag is a pack with an air cylinder and buoyancy balloon
which inflates when triggered, to wrap around your shoulders and head.
It’s been 30 years in R&D and costs over $1,000+, but the technology has
now been proven and their survival success rate is very high. I just
bought one from Snowpulse.
Winter avalanche debris in Shovel flat photo: GW Nov.2011
Evidence of avalanching? The ice caves in the Matukituki were first
recorded by Maud Moreland in her classic turn of the century book
"Travels through South Westland"
Surface Hoar on Von Bulow, Franz Josef Glacier Dec.2011
Formed by water vapour transfer, sublimating onto snow crystal branches
when temperature very strong (excess of 1degC/10cms.)
(see Franz/Fox Expeditions - Mt. Aspiring
New developments on Avalanche
transceivers and cliff rescue - GW
IKAR (Recent Sweden Workshop)
Snowpulse, Avalanche survival AIR Bag
In 2011 Geoff purchased a Snowpulse AirBag for work safety in avalanche
terrain and emergency SAR ops. The technology has been over 30yrs in
development following the avalanche death of a young Italian skier,
who's wealthy family set up a research fund to find devices to prevent
avalanche burial (the concept of the Airbag). Geoff saw the AirBag at a
recent Avalanche Conference and was so excited by the Snowpulse unit,
that he bought one.
AVALANCHE FLOTATION DEVICES by WorkSafeBC (extract
from CAA magazine by GW? Can. Aval. Assoc.
In the Coroner’s Report into the deaths of Ms. Kimberly Anne Manchip and
Daisuke Matsui, both of whom were caught in an avalanche and died from
asphyxiation, the Coroner found that evidence from the incident pointed
lifesaving potential offered by avalanche flotation devices. The Coroner
recommended that WorkSafeBC “evaluate the efficacy of avalanche
use by workers whose workplace involves frequent and extensive exposure
conditions which may result in life-threatening avalanches.”
Existing literature on avalanche flotation devices has been reviewed in
evaluate the performance of these devices.
2. LITERATURE REVIEW
2.1 Avalanche Fatalities
In the majority of avalanche fatalities, the fatality is due primarily
Data from Canada, the United States, and Europe indicate that asphyxia
accounts for up to 70-80% of avalanche deaths.1,2
Asphyxia has been found to
occur rapidly after burial. Time to recovery, therefore, is a critical
regards to survival. In cases of complete burial,3
92% of victims will be found
alive if recovery is accomplished within 15 minutes; however, the
drops to 30% at 35 minutes after burial.4
Depth of burial is another critical factor with regards to survival; the
a live recovery decreases as depth of burial increases.5
The chance of survival
in the case of complete burial has been found to be only about 50%,
survival probability of not or partially buried people has been found to
2.2 Avalanche Flotation Devices
Avalanche flotation devices aim to prevent asphyxiation by reducing the
burial in the event of an avalanche. These devices are designed to
flotation, keeping the wearer at the surface of the avalanche, and
or minimize burial.
1 Boyd, J. et al (2009) at 509
2 Radwin, M.I. & Grissom, C.K. (2002) at 144
3 Complete burial is defined to mean that the victim’s head and chest
are covered with snow.
4 Falk, M., Brugger, H., Addler-Kastner, L. (2001) at 140
5 Radwin, M.I. & Grissom, C.K. (2002) at 144
6 Tshirky, F., Brabec, B., & Kern, M. (2000) at 2
1. ABS Avalanche Airbag System. ABS Facts.
Retrieved July 27, 2009 from
2. Boyd, J. et al. (2009). “Patterns of death among avalanche
fatalities: a 21 year
review.” Canadian Medical Association Journal 180(5): 507-512.
3. Brugger, H. and Falk. M. (2002).
Analysis of Avalanche Safety Equipment for
Backcountry Skiers. Retrieved July 24, 2009
4. Brugger, H. et al. (2007). “The impact
of avalanche rescue devices on survival.”
Resuscitation 75: 476-483.
5. Falk, M., Brugger, H. and Adler-Kastner, L. (2001). “Calculation of
survival as a
function of avalanche.” Wilderness and Environmental Medicine 12:
6. Hohlrieder, M. et al. (2007). “Pattern and severity of injury in
avalanche victim.” High
Altitude Medicine and Biology 8(1): 56-61.
7. Kern, M., Tschirky, F and Schweizer, J. (2002). “Field tests of some
rescue devices.” In Proceedings of the International Snow Science
Penticton, BC, Canada, September 9-October 4, 2002. Retrieved July 24,
8. Radwin, M.I. and Grisson, C.K. (2002). “Technological Advances in
Survival.” Wilderness and Environmental Medicine 13: 143-152.
9. Scrivener, L. (2008). Of airbags, Avalungs and avalanche safety.
7, 2009 from
10. Tschirky, F. and Schweizer, J.(1996). “Avalanche Balloons –
Results.” In Proceedings of the International Snow Science Workshop.
-29, 1996, Banff, AB, Canada. Retrieved July 27, 2009 from
11. Tschirky, F., Bernhard, B. and Kern, M. (2000). “Avalanche Rescue
Switzerland: Experience and Limitations.” In
Proceedings International Snow
Science Workshop, Big Sky, MT, USA, October
2000. Retrieved July 24, 2009 from
HOW MANY DIFFERENT SNOW
Kate Bush has just released a new music album called:
50 Words for Snow - So how many are there?
Some say "no two crystals
are exactly alike!"
I gathered William
Bentley, a paraplegic in Vermont in the 1930's, with a microscope and an
enquiring mind photographed some 3,000 individual snowflakes.
Were they all different?
I don't know.
William Bentley Crystal Photos/From: Fieldguide to Snow Crystals by Ed
However, ages ago, I also recalled hearing from one mountain
source, that there were 36 words for snow! My interest was further
fuelled by the acquisition of the definitive text by G. Somerville,
Snow Structure & Snowfields, 1936 where he described some crystals in
english for the first time - the European terms of snow primarily used
Were there definitive Inuit words for what we know as needles, stellars,
plates and spatial dentrites?
A chance couple of hours in a Nthn. Alberta Library led me to some
Inuit Dictionaries which included words for snow. As I looked
through the pages I could see my quest for a specific number of
different crystals evaporating into another realm of word usage.
The value of the words
became more apparent when I later spent more time construction Igloos
with Logan Park High School students. The words in Inuit were mostly
environment words, such as: "Snow blowing above the knees/or
So, my the quest continues on a common topic, but world's apart in
application of word useage. GW
Keep fit, Geoff Wayatt