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1
Q

We are always hoping for them to change into … these are as a bunch of tennis balls in a tupperware bin with lots of surface area to make strong bonds to one another.

A

rounds. We can think of rounds

2
Q

The good news or sometimes good news is our snowpack is always changing. Depending on …4 our snow crystals change form

A

weather, load, temperature & vapour movement

3
Q

When we head out into popular backcountry areas sometimes the weak layers can get broken up from all of the snowboarder / skier traffic, we call this …

A

compaction “Tracks never mean that a slope is safe.”

4
Q

We can identify a loose avalanche by:

A

The avalanche starting from a single point

Fanning out, creating a triangle shape

5
Q

Loose snow avalanches do not need a …. It is the surface snow that slides and can sometimes step down to a slab if there is a buried weak layer below.

A

weak layer

6
Q

… avalanches are the monsters that we hear about in the news. They tend to be larger than loose avalanches & release suddenly & all at once quickly turning a fun day into a potentially deadly one.

A

Slab

7
Q

What we need for a slab avalanche to occur:

4

A

Weak layer
Slab
Trigger
Terrain steep enough to slide

8
Q

T: This is the smooth wall that forms where the fracture line is at the top of the avalanche.

A

crown face

9
Q

Our … snow avalanches happen mid winter when the snow is cold and the riding is good.

A

dry

10
Q

..avalanches happen when the weather warms up, typically in the spring or if we have a mid winter warm u

A

.Wet

11
Q

Some common signs that the snow is starting to become wet are; … (little balls of snow rolling down the surface) and snow falling out of trees.

A

pin wheeling

12
Q

Avalanche sizing is …., each size is 10 times bigger than the previous size

A

exponential

13
Q

It is challenging to estimate size & mass in the field so the easiest way to size an avalanche is by …

A

destructive potential

14
Q

a size 1 can be deadly depending on what terrain we are in

A

t

15
Q

What were the 3 things we needed for a slab avalanche ….

A

Weak layer
Slab
Trigger
terrain

16
Q

T: A relatively thick cohesive layer of snow that slides during a slab avalanche

A

slab

17
Q

what happens to weak layer when slab av

A

Collapses

18
Q

what role does bed surface play in slab av

A

sliding surface

19
Q

loose avalanches do not need a weak layer

A

t

20
Q

Characteristics of a start zone: 2

A

Steeper slope angle

We usually observe the crown in the start zone of an avalanche path

21
Q

T: The area covered by an avalanche in motion.

A

track

22
Q

T: This is where it all comes to a stop.

A

run out zone

23
Q

T: the sliding surface

A

bed surface

24
Q

Remember we need a …3 for a slab avalanche to occur

A

slab, weak layer & trigger

25
Q

6 natural triggers

A
Cornice fall
New snow
Sun
Rain
Wind loading
Animals
26
Q

5 human triggers

A
Snowmobiles
Snowboarding & Skiing
Snowshoeing
Other machines – helicopters, groomers ect
Explosives
27
Q

Crusts create the perfect sliding surface.

A

t

28
Q

when stability is the question … is the answer.

A

terrain
How can we mitigate our risk in the backcountry? Terrain choice!
matching our avalanche terrain to the avalanche conditions.

29
Q

We like to call our cut blocks …

A

surface hoar farms. It is the perfect place for surface hoar to grow & is generally well protected from the wind by the trees left surrounding it

30
Q

pros and cons of uniform slope

A

While uniform slopes can increase the consequence of a large propagating avalanche when the right conditions are present, the less convoluted a slope is, the more evenly distributed the snow will be, resulting in fewer common trigger points

31
Q

… is the direction a slope faces

A

Aspect

32
Q

how to find out aspect in the backcountry

A

When we are in the backcountry we can figure out the slope aspect by turning our back to the slope & holding a compass in front of us. Whatever that compass reads is the slope aspect.

33
Q

Why is aspect important?

A

wind exposure, sun exposure & snow metamorphism.

34
Q

3 ways sun influences

A

More likely to have a sun crust & / or temperature crust

Typically has a shallower snowpack then North aspects

Can undergo rapid warming, especially in the spring time

35
Q

shaded 3?

A

Generally face North or East

Can preserve weak layers (such as surface hoar) longer then south aspects

More likely to have surface hoar or facets

36
Q

S or N sun facing?

A

South facing: direct sun, wind scouring

North facing: Wing loading, shade

37
Q

Our wet slab avalanches will either fail on a weak layer or when our snowpack becomes .. (the entire snowpack is 0 degrees) we will see these monsters side right to ground.

A

.isothermal

38
Q

Signs that things are heating up:

A

pinwheeling

no snow on trees

39
Q

Long term sun affect can result in a …

A

sun crust.

40
Q

This means our typical or prevailing winds are …

A

westerly or south westerly winds.

41
Q

T: is the aspect that faces the wind.

A

windward side

42
Q

id we had westerly winds the … aspect would be the windward side

A

west

43
Q

The opposite aspect of the wind direction is called ..

A

.leeward

44
Q

Why are thin spots dangerous

A

. We may have a problem that is 2 meters down & difficult for us to trigger until we hit a thin spot where our problem might only be 30 cm down creating an easy trigger point that can result in a monstrous avalanche.

45
Q

… occurs when the wind is blowing snow over ridges onto the leeward side.

A

Ridge top loading

46
Q

.. occurs when the wind is transporting snow across the slope.

A

.Cross loading

47
Q

So how do we know when something is wind loaded?

A

Does it look fat & pillowy?

Better than anything else around?

Very good chance it is wind loaded!

48
Q

T: hey are essentially a large overhanging chunk of snow and when you are standing on them you are typically standing over air… not on a mountain.

A

cornices.

49
Q

When do cornices collapse?

A

random
We do see an increase in cornice collapses at the start of the season when they are just forming & are still weak as well as at the end of the season when the sun is out and warming those bad boys up.

50
Q

How do we know if we are on a cornice?

A

probe for earth

51
Q

We have 3 main elevation bands we talk about when we are trip planning & looking at our avalanche bulletin.

A

alpine
treelike
below treeline

52
Q

characteristics of alpine

A

Open slopes

No trees

Not all mountains have alpine

Contains the terrain that is usually the most exposed to sun, wind, cold, and precipitation

Start zones of large avalanche paths

53
Q

characteristics of treelike

A

Enjoyable tree skiing

Nicely spaced trees

Exposure to sun, wind, cold, and precipitation is generally less here than in the alpine but greater than below treeline

Start zones of large avalanche paths or tracks of very avalanche paths can run through here

Can expect to find well preserved surface hoar

54
Q

characteristics below treelike

A

Tight trees

The heinous part of the tour that you just need to get through

Covered by forest

Usually sees less sun, wind, cold & precip

Variable snowpack

Can see more crusts throughout the winter being lower elevation

Runout zones may clear out areas below treeline

55
Q

… are a terrain feature we want to try to avoid in the backcountry. They are an unsupported roll under tension making for an extremely easy trigger point.

A

Convexities or convex rolls

56
Q

.. are the opposite. The are a gradual mellowing out of the slope and give it lots of support.

A

.Concavities

57
Q

Below are some examples of anchors

A

trees

rocks

58
Q

when do trees hurt

A

If we only have one or two trees on the slope then they are a potential weak point. We can see Facets form around them and want to make it a habit to avoid the single tree on the slope.

59
Q

when are rocks good vs bad

A

. If they are large enough to break up a weak layer and isolate it then they can help us out. But if we only have one rock or they create a shallow rocky spot then they turn into an easy trigger point.

60
Q

Common trigger points:

A

Between anchors

Thin spots (potentially brings us that much closer to the weak layer)

Rocky outcrops

Convexities

The top of a steep slope

Locations where the snowpack has reached critical loading through wind loading or new precipitation;

Places where the snowpack is perforated by rocks or trees.

61
Q

why thin spots dangerous

A

Lets say we have a deep persistent avalanche problem that is 2 meters down, tricky for us to trigger… until we hit a thin spot, lets say the wind has been blowing creating a thin spot. Now our deep persistent problem is only 50cm down

62
Q

… refers to the changes we see within the snowpack as we move through terrain

A

Spatial variability

63
Q

Factors that effect spatial variability:

A
elevation 
aspect 
ground cover 
slope shape 
terrain features
64
Q

The trees along the edge of an avalanche path are called …

A

trim lines the trees get older the further away you get

65
Q

Some common terrain traps we want to be able to identify & avoid when traveling in the backcountry are:

A

Gullies

Cliffs/rock bands

Thick trees

Creeks

Lakes

Roads

Sharp transitions

Boulder fields

Crevasses

66
Q

If we can find a … to keep us higher & out of terrain traps that is our best option.

A

ridge or rib feature, high points

67
Q

When riding down something we want our escape route to be a ..degree angle and ideally towards a high point or out of the avalanche path to a safe spot

A

45

68
Q

… is when trees only have branches on one side. This is a vegetation clue we find in avalanche paths and run out zones.

A

Flagging

69
Q

Natural avalanches possible, human triggered avalanches likely what rating

A

considerable = most callenging rating

70
Q

moderate. Do not let your guard down as we can still see avalanches up to ..

A

size 2!

71
Q

Loose wet management techniques

A

Avoid start zones & paths when the snow is moist

72
Q

Wind slabs management techniques

A

Recognize and avoid areas where wind slabs have formed

73
Q

In BC our weather comes from the west coast typically resulting in West or South West winds. When we have a cold snap we can expect to have … winds.

A

northerly

74
Q

how can you recognize wind slabs

A

Can recognized by: appearance of snow surface, changes in snow surface hardness, hollow drum like sounds, shooting cracks

75
Q

Persistent slabs managment techniques

A

Conservative terrain choices

Allow extra time to stabilize

Cautious approach to new terrain

Increase caution after storms or during warming periods

76
Q

deep persistent slabs management techniques

A

Conservative terrain choices

Allow extra time to stabilize

Cautious approach to new terrain

Increase caution after storms or during warming periods

77
Q

cornices management techniques

A

Approach ridges cautiously

Avoid travel on or near overhanging cornices

Limit exposure time on slopes with cornices above

78
Q

Storm slabs

A

Conservative terrain choices during & after storms

79
Q

wet slabs

A

Avoid start zones & paths when the snow is moist

80
Q

loose dry

A

Avoid Terrain Traps

Avoid large steep slopes

Sluff management

81
Q

glide cracks

A

avoid if you see one. A glide crack will fail at the ground, this is the easiest way to identify a glide crack. Not all glide avalanches start as a glide crack but it can be a good indicator. Our glide avalanches typically happen on wet smooth surfaces such as grass or smooth rock. We do not frequently see glide avalanches but when they do happen they tend to be very destructive since they take the entire snowpack with them.

82
Q

what does SPAW stand for

A

special public avalanche warning

83
Q

when are SPAW warnings issued

A

There is a particular avalanche hazard or persistent weak layer public is not picking up on

Blue bird conditions after storm periods and pent up powder stoke

84
Q

Mountain Information Network (MIN)what is ti

A

Avalanche Canada created the MIN network as an information sharing tool for recreational users.

85
Q

dif types of MIN reports

A

quick report, avalanche report,

incident report, snowpack report

86
Q

The Avalanche Terrain Exposure Scale (ATES) was created by Avalanche Canada & Parks Canada as a tool for our pre trip planning. They went to popular areas throughout our province and rated the terrain into three categories; …3

A

simple, challenging & complex.

87
Q

We always start our trip planning by looking at the Avalanche Bulletin & weather. From that information we pair it with the…

A

terrain that is appropriate for the conditions that day.

88
Q

… is primarily low angle slopes, with limited exposure to avalanche paths & has lots of opportunities for us to reduce our risk.

A

Simple terrain

89
Q

The biggest indicating factor that we are in Complex terrain is exposure to ….

A

multiple overlapping avalanche paths.

90
Q

red and yellow in the trip planner?

A

The red lines are the main avalanche paths in that zone (not all).

Yellow line is the trail in.

91
Q

signs of instability from the snow

A

Whumpfing
Shooting cracks
Recent avalanches
Pinwheeling

92
Q

Weather factors that influence avalanche danger:

A

Precipitation
wind speed and direction
temperature
solar radiation

93
Q

what time of precipitation is dangerous

A

Anything that comes in hard & fast is going to cause avalanche danger to spike immediately.
With smaller accumulation over time we could expect our avalanche danger to slowly rise.

94
Q

what kind of temp dangerous

A

rapid change

95
Q

If we have a rapid drop in temperature we could expect to start seeing …

A

Facets forming after a couple of days creating a weak layer for future snowfalls to sit on. We could see loose dry avalanches as our snow starts to facet out as well.

96
Q

Our avalanche forecast is only as good as our …

A

weather forecast.

97
Q

weather: Next I am going to use …. and type in the closest town. You can move the red spot around and place it on your exact location for the day.

A

.spotwx.com

98
Q

T: scroll along with mouse to get temps, total snow amounts and cloud cover percentage. Further down the page you will find wind speed & direction.

A

GEM- LAM

Look at the top for elevation & make sure it is at the appropriate elevation band for your trip.

99
Q

why look at RH

A

Relative humidity (we need a high RH for surface hoar to form)

100
Q

..: How much snow has fallen in 12 hours. Measured in centimetres. Cleared in the morning and afternoon by ski patrol.

A

.HN board

101
Q

…: Storm snow board. They will leave this board until the storm ends so we can have a total amount of snow accumulated from the storm as well as settlement rates.

A

HST board

102
Q

…: Height of snow. Total amount of snow from the ground.

A

HS

103
Q

…: A running total of the calculated hourly new snow.

A

Run tot calc hr new

104
Q

…: This is our average wind speed in kilometres per hour

…: Wind direction. The number correlates to our compass.
….: the max gust in the past hour in kilometres per hour.

A

2 min avg WS KPH
Spot WD
Max gust KPH

105
Q

What if our points are too high?

A

change terrain

106
Q

safe travel habits

A
Safe spot to safe spot
Reduce exposure to one on slope at a time
Watch your buddies!
Regroup and reassess.
Be ready to act.
Don’t tether gear to your body.
Avoid terrain traps and cornices
Escape route.
void traveling above & below people.
107
Q

Human behaviours differences?

A
familiarity 
acceptance 
commitment 
expert halo 
tracks 
social proof 
risk tolerance
108
Q

positive human behaviours

A

communication
;leadership
patience
discipline

109
Q

Personal performance check in:

A
sleep 
lifestyle 
injuries 
mental health 
confidence in skill set
110
Q

When we talk about our avalanche risk we are talking about: 2 things

A

Avalanche Hazard + Vulnerability = Avalanche Risk

111
Q

If we have a high level of uncertainty then we have low …

A

confidence.

112
Q

The best example of uncertainty is when our danger rating is …

A

considerable.

113
Q

They may go out & make tons of pour decisions but have luck on their side & don’t suffer from any sort of consequence :T

A

non event feedback

114
Q

what does the third antenna do

A

The third antenna in the three antenna units has a very short range and assists with the fine search phase of the search.

115
Q

The effectiveness of an avalanche transceiver is related to: 4

A

How it is worn.
How it is functioning.
The ability of the person operating it (PRACTICE, PRACTICE, PRACTICE!!)
Your companions

116
Q

ONLY USE ..BATTERIES.

A

.ALKALINE

117
Q

With our standard 3 antenna transceivers we will emit a signal as shown in the photo below.

We call these

A

flux lines (curve into them not straight)

118
Q

The older transceivers do still work but they suffer from …2which can both be deadly in a rescue

A

signal overlap & interference

119
Q

Some of our favourite features are:

on a transiver

A

group check
multiple burial indicator
marking function
Revert to send

120
Q

The … symbol indicates that signals are received from additional buried subjects that cannot be isolated and entered in the list of buried subjects ye

A

+

121
Q

When our transceivers are in send they need to be at least… cm away from any device that can interfere.

A

20

122
Q

When our transceivers are in search they needs to be at least .. cm away from any device that can interfere.

A

50

123
Q

how often do a transfer check

A

everyday

124
Q

There are two ways we can complete a transceiver check.

A

group check

125
Q

We also need to re do our transceiver check if we switch our transceivers between search / send weather it is for a practice scenario or real life rescue situation.

A

t

126
Q

how to check without group check

A

The checker will turn their transceiver into search & stand far enough away that they do not pick up everyones transceiver signals all at once (5o meters).
The rest of the group will put their transceivers into send & keep them in send for the rest of the day.
The last person always checks the checker. They can switch into search mode & ensure the checker’s transceiver is properly sending. Then everyone stays in send for the remainder of the day.

Each person in the group will walk up to the checker 1 at a time.

127
Q

When purchasing a probe make sure it is … meters!

A

3

128
Q

The skiing / snowboarding air bags have the trigger on the left side of the bag so you would reach across with your …

A

right hand

129
Q

What to do if caught in an avalanche

A
yell avalanche 
escape route 
Airbag or Avalung
ditch gear
swimming
Grab trees or rocks
Make an airspace & extend hand up
Try to relax
130
Q

a backstroke motion will help keep you afloat. If possible get your feet pointed downhill to help protect your head from trauma.

A

t

131
Q

A couple of key points that regularly get missed:

A
choose a leader
turn all trans to search 
asses for safety 
surface clues 
call for outside help
132
Q

Looking at the chart above we can see our chances of survival drop drastically at the … minute mark.

A

15

have 10 min to save someone

133
Q

The first phase of our transceiver search is called our …

A

signal search.

In this search phase our transceiver DOES NOT have a signal.

134
Q

If you have multiple searchers & a large debris field spread out .. meters from each other & walk straight down

A

40

135
Q

stages of search

A

signal search
course search
10 m check (slow)
fine search (knee height , no arrow)

136
Q

course search is how far away

A

from 40 – 70 meters away.

137
Q

fine search in what range

A

3 m

138
Q

If our lowest number is 0.5 then they are roughly …deep.

A

50cm

139
Q

steps

A
stop asses safety (future hazards)
head count 
choose leader
switch to search mode
call for help (location, nature, name, phone number)
determine where to search 
search for signal and visual cues  
yell for others when signal gotten
call for probe and shovel
 follow signal to burial area
shovel fast and effectively
140
Q

how to probe

A

We want 2 hands on the probe & to keep our probe perpendicular to the ground.

Our spacing is 25cm from each probe hole (about a boot length).
We want to probe all the way down to the ground (or as deep as we can) so we get a clear indication when we get a strike.
probe perpendicular to slope

141
Q

If the lowest reading on my transceiver is 4 meters, I know that I need to …

A

dig down a platform until my lowest reading is within 3 meters (my probe length).

142
Q

Once we get a strike

When we get a strike we want to ..

A

.leave the probe in until we have that person out!

143
Q

when do you hit mark

A

As soon as you get a probe strike you can hit the mark button (if you have it) on your transceiver. You do not want to hit it before the probe strike in case it is a false positive.

144
Q

is the hardest part of the rescue & takes the longest (prepare to find this out first hand on the field day!). :T

A

shovelling

145
Q

We shovel in a …, lining up a shovel length away from one another.

A

conveyor style

146
Q

We are going to start at the probe unless it is a deep burial or we do not have the optimal number of shovelers, then we want to ..

A

.start back from the probe & shovel a ramp in towards them.

147
Q

Always shovel on the … side of the probe.

A

downhill

148
Q

We want to dig a … into the person so we can easily get them out of there. If we dig directly to them, we will end up with a hole straight down & will be unable to get them out.

A

ramp

149
Q

We want to rotate every …minutes. It is best to get the second person to call the rotation.

A

2 – 3

150
Q

If you have more than … people shovelling it can start to get crowded

A

4

151
Q

rescue without transceiver

A

visual sweep
spot probing
probe line

152
Q

Probe lines are time consuming & have never had a live recovery.

A

t

153
Q

5 search phases

A

Visual sweep – clues, spot probing

Signal search

Coarse search

Fine search

Pinpoint search – probing

154
Q

…2 are great tools to have in the backcountry. They allow you to send & receive messages as well as hit an SOS button

A

inReaches or SPOTS

155
Q

Emergency communication devices

A

inReaches or SPOTS

radios ( VHF)

156
Q

some essentials we need to carry with us when heading into the backcountry:

A

Transceiver

Probe

Shovel

Extra batteries

Airbag – if possible, is a great addition

Helmet

Emergency communication – SPOT or inReach

Radio

Repair kit – having a solid repair kit for your equipment is key. You do not want to call Search & Rescue for a broken binding.

Navigation – I use gaia & fat maps on my phone. If you are going to rely on phone apps be sure to pack a battery pack with you as well.

Bivy

Warm clothing

Food

Water

Fire Starter

First Aid Kit – have a bomber first aid kit. Buy one & then add what you need to it. We highly recommend taking some wilderness first aid training!

Avaluator

Solid group that communicates well, makes group decisions & has rescue skills dialled

157
Q

decision making supports we can use

A
Avalanche Forecast
ATES Ratings
Avaluator
Trip Planner:
Weather Forecast: Avalanche Canada’s mountain weather forecast, environment Canada, Spot WX & weather stations to name a few!
Information from locals
the internet
158
Q

… are what we are going to do to achieve that goal.

A

Objectives

159
Q

Plan your Trip: We are going to start with our at home … chart to see what terrain is appropriate for the current conditions. From there we can use Avalanche Canada’s Trip Planner, guide books, blog posts & information from locals to decide where we want to go.

A

Avaluator

160
Q

Evaluate slopes: before traveling up or down anything pull out your … & have a group discussion.

A

avaluator

161
Q

levels of competency?

A

Unaware – No Training

Beginner – AST 1

Intermediate – AST 2

Advanced – Professional

Expert – Very experienced professional