basic avalanche awareness - unis · basic avalanche awareness: an introduction to snow safety in...
TRANSCRIPT
![Page 1: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/1.jpg)
Basic Avalanche Awareness: An introduction to snow safety in Svalbard
Holt Hancock 07/02/2017 Cryoslope Svalbard photo
![Page 2: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/2.jpg)
Introduction • Avalanches occur throughout
svalbard
• Unique avalanche conditions and problems associated with Svalbard’s climate and setting
• Recreationalists typically
cause avalanches that affect their group – This is preventable!
Eckerstorfer and Christiansen image
![Page 3: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/3.jpg)
Introduction
If you don’t know, don’t go
Think terrain, not snow
Human factors
3 Axioms / Things to remember:
![Page 4: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/4.jpg)
If you don’t know, don’t go
• Types of avalanches in Svalbard
• Weather warning signs
• Snowpack warning signs
![Page 5: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/5.jpg)
What is an avalanche?
A mass of snow sliding, tumbling, or flowing down an inclined surface
![Page 6: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/6.jpg)
What is an avalanche?
A mass of snow sliding, tumbling, or flowing down an inclined surface
![Page 7: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/7.jpg)
Svalbard (Snow) Avalanches
4 Types • Slab • Cornice fall • Slushflows
(slush avalanches)
• Loose snow
![Page 8: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/8.jpg)
Slab avalanches
– Cohesive layer of snow that slides on underlying layers
– Triggered by the victim or a member of their party
SLF photo
Most recreational avalanche accidents involve slab avalanches
![Page 9: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/9.jpg)
Slab avalanches
Slab: wind drifted snow or new storm snow
Weak layer: facets (sugar snow)
Bed surface: ice layer or hard old snow
![Page 10: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/10.jpg)
Slab avalanches Lia, 2010 Max Eckerstorfer photo
Crown (Slab)
Weak layer
Bed surface
![Page 11: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/11.jpg)
Slab avalanches
Starting zone / release area
Track / Path
Runout / deposition zone / debris
![Page 12: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/12.jpg)
Slab avalanches
Cryoslope Svalbard photo
![Page 13: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/13.jpg)
Slab avalanches Erik Næss photo
![Page 14: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/14.jpg)
Slab avalanches
Cryoslope Svalbard photo
![Page 15: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/15.jpg)
Cornice fall avalanches First, what is a cornice?
Cryoslope Svalbard photo
![Page 16: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/16.jpg)
Cornice fall avalanches
Not always this obvious where the cornice starts!!
Cryoslope Svalbard photo
![Page 17: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/17.jpg)
Cornice fall avalanches
Cryoslope Svalbard photo
• Very common avalanche type in Svalbard
• Slab avalanche often releases due to impact of falling cornice
• Difficult to forecast timing of cornice failure
• End of snow season • Warm temperatures • During storms?
![Page 18: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/18.jpg)
Cornice fall avalanches
Cryoslope Svalbard photo
![Page 19: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/19.jpg)
Slushflows
Cryoslope Svalbard photo
![Page 20: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/20.jpg)
Slushflows
• Slush avalanches
• Associated with heavy rain / snow melt
• Snowpack becomes saturated
• Occur in different terrain than other avalanches
Svalbardposten photo from January 30th, 2012
![Page 21: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/21.jpg)
Loose snow avalanches
Cryoslope Svalbard photo
![Page 22: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/22.jpg)
Avalanche Triangle
Terrain
![Page 23: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/23.jpg)
Is the weather contributing to increased avalanche danger?
Terrain
![Page 24: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/24.jpg)
Warning Signs: Weather
Recent heavy snowfall (>15 cms) Erik Næss photo
![Page 25: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/25.jpg)
Warning Signs: Weather
Strong winds; especially in combination with loose snow
Cryoslope Svalbard photo
![Page 26: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/26.jpg)
Warning Signs: Weather
Rapid warming and rain
Cryoslope Svalbard photos
![Page 27: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/27.jpg)
Is the snowpack unstable?
Terrain
![Page 28: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/28.jpg)
Warning Signs: Snowpack Recent avalanche activity
Cryoslope Svalbard photos
![Page 29: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/29.jpg)
Warning Signs: Snowpack Shooting cracks and ‘‘whumpfing’’
![Page 30: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/30.jpg)
If you don’t know, don’t go
• What can we do to know? – Check the weather and avalanche forecast
• Varsom.no
– Look for signs of recent avalanche activity and unstable snow
– Ask!
• Think terrain, not snow
![Page 31: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/31.jpg)
Think terrain, not snow If snow is the problem, terrain is the answer
Terrain
![Page 32: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/32.jpg)
What is avalanche terrain? Release areas • Avalanches typically
release on slopes between 30 and 45 degrees
• ‘‘steep slopes’’
Cryoslope Svalbard photo
![Page 33: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/33.jpg)
A brief note on slushflows:
• Release from lower angle terrain (typically 5 – 30 degrees)
• Watch for water pooling in the snowpack
Erik Hestnes figure
![Page 34: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/34.jpg)
What is avalanche terrain?
Runout Zones • During periods of
elevated avalanche danger, valleys are not necessarily safe!
• It is possible to trigger avalanches from below
Cryoslope Svalbard photo
![Page 35: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/35.jpg)
Terrain Traps Especially dangerous avalanche terrain
![Page 36: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/36.jpg)
Think terrain, not snow
• Learn to identify slope angles – Avoid steep slopes
• Be aware of your surroundings – Runout zones – Terrain traps
![Page 37: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/37.jpg)
Human factors
Terrain
What were they thinking?!
What was I thinking?!
People
![Page 38: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/38.jpg)
The human factor
Common human factors / errors • Time constraints (weekend warrior) • Familiarity • Group dynamics • Expert halo • Blue sky syndrome
Most avalanches involving people are triggered by their own actions!
![Page 39: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/39.jpg)
The human factor
• Safe travel protocols – Basic avalanche gear – One at a time in avalanche terrain
• Communicate within your group – Speak up!!
• Have a plan…but be flexible!
How can we reduce our risks?
![Page 40: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/40.jpg)
Trip Planning
Consider:
• Is the weather contributing to increased avalanche danger?
• Is the snowpack unstable?
• Will I be traveling in avalanche terrain?
• How are human factors influencing my (our) assessment of the avalanche hazard?
![Page 41: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/41.jpg)
Again, remember:
If you don’t know, don’t go
Think terrain, not snow
Human factors
![Page 42: Basic Avalanche Awareness - UNIS · Basic Avalanche Awareness: An introduction to snow safety in Svalbard. Holt Hancock . 07/02/2017. Cryoslope Svalbard photo. Introduction • Avalanches](https://reader035.vdocuments.us/reader035/viewer/2022070810/5f095ce17e708231d4267a3e/html5/thumbnails/42.jpg)
Questions?
Have a fun (and safe) winter and spring!