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love you from carson

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he biggest way in which avalanches affect people is by causing death or injury. ... Asphyxiation is the most common cause of death, followed by death from injury and lastly by hypothermia. People buried in the avalanche have more than a 90 percent survival rate if found within 15 minutes.Apr 25, 2017

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Avalanches

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Banff, Yoho and Kootenay National Park Highway Avalanche Control

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Every winter, avalanches threaten highways and railway lines in Canada's Mountain National Parks. Travel by air through Banff, Yoho and Kootenay national parks with our Visitor Safety Specialists as they perform helicopter explosive control on some of Canada's western Canada's most important transportation corridors.

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Avalanches

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Canadian Rockies Highway Avalanche Control - Kootenay National Park  - March 10, 2014

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March 10, 2014 - Travel by air through Kootenay National Park (Highway 93S) with our Visitor Safety Specialists as they perform helicopter explosive control. This team effort includes many Parks staff members including highway staff who are on stand-by to clean up any debris that reaches the roadway to ensure routes can be reopened quickly.

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Canadian Rockies Highway Avalanche Control - Kootenay National Park  - March 10, 2014

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March 10, 2014 - Travel by air through Kootenay National Park (Highway 93S) with our Visitor Safety Specialists as they perform helicopter explosive control. This team effort includes many Parks staff members including highway staff who are on stand-by to clean up any debris that reaches the roadway to ensure routes can be reopened quickly.

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Avalanches

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Take a ride in the helicopter with our avalanche crew and check out what it was like doing avalanche control along the Coquihalla after a record-breaking snowfall.

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A landslide happens when the ground cant hold it anymore and just gives out by the rain loosening the dirt.

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it makes you late for work you go poor mess up water you kill

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sometimes the landslides can push cars and push over many other things like in this video

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Image result for how do avalanches formavalanchevanessa.weebly.com
There are two basic elements to an avalanche: a steep, snow-covered slope and a trigger that causes a weak layer within the snow pack to collapse. This video segment adapted from NOVA reveals that the shape of the ice crystals of snowflakes within a snow pack is also a critical factor.

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“Loose snow” avalanches account for only a small percentage of deaths and property damage. “Slab” avalanches (the most lethal) are cohesive plates of snow sliding as a unit.

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Avalanches can occur without warning, sending thousands of tons of debris and ice downhill at breakneck speeds.

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Avalanches- What are they? How do they work?

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11 Facts About Avalanches
website

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There are two basic elements to an avalanche: a steep, snow-covered slope and a trigger that causes a weak layer within the snow pack to collapse. This video segment adapted from NOVA reveals that the shape of the ice crystals of snowflakes within a snow pack is also a critical factor.

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guys

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Snow Cover
The two main avalanches are loose snow and slab avalanches.  These two types of avalanches are distinguished by the snow condition at the origin.  However, sometimes classifications must be modified on long avalanches, due to the fact that snow conditions vary throughout the avalanche.  All avalanches have a great potential energy, that can be determined by their height and the force of an avalanche is simply F= ma.  This means that if a small avalanche contains 1000 kg of snow, it has a force of 9810 Newtons.

Loose snow avalanches usually start at a point or small area and expand as they move.  They are a result of snow that has been deposited at a steeper angle then the snow’s natural angle of repose.  The most dangerous loose snow avalanches are made of wet snow.  This is because the wet snow is denser and has a greater destructive force even though the velocities may be low.  The diagram shows the differences between loose snow and slab avalanches.

The ABC of Avalanche Safety

Slab avalanches are the most dangerous type of avalanche.  They are the largest source of winter hazards, and most are triggered by the victims.  Slab avalanches form in almost all types of snow.  Wind is an important factor to these avalanches, because it causes and unstable slab.  However, wind alone will not cause a slab avalanche.

Gravity and the strength of the bonds between snow layers are important in slab avalanches.  This is because gravity is the force which is pulling the slab down the mountain.  When the force of gravity is greater than the bond between layers the gravity causes the top layer to separate and slide down the mountain.

The diagram below gives a good idea as to how a slab avalanche moves.  It is easy to see how after the avalanche is triggered there is start zone, which moves down the "track" and finally ends in a debris toe.  As the avalanche moves down the mountain kinetic energy increases while the potential energy decreases.

http://www.uoregon.edu/~opp/snow/avalanche/avalanchetypes.htm

Terrain
Slab Avalanches
Cornices & Ice
Slope Stability
workscited
Index

Created by Sarah Schlichting for Physics 212
Last modified 04-04-03

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avalanches account for only a small percentage of deaths and property damage. “Slab” avalanches (the most lethal) are cohesive plates of snow sliding as a unit.
Each year avalanches kill more than 150 people worldwide.
In 90% of avalanche accidents, the victim or someone in the victim’s party causes the snow slide.
The human body is 3 times denser than avalanche debris and will sink quickly. When the slide slows, clear air space to breathe, then punch your hand skyward. Once the avalanche stops, it settles like concrete.
Unlike its portrayal in movies, noise does not trigger avalanches. Avalanches are caused by four factors: a steep slope, snow cover, a weak layer in the snow cover, and a trigger.
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The vast majority of avalanches (90%) occur on slopes with angles between 30 and 45 degrees. Steeper slopes tend to continually slough snow, keeping a deep snowpack from building up. The snowpack on flatter slopes requires more force to move.
Avalanche risk is at its greatest 24 hours following a snowfall of 12 inches or more.
Avalanches can reach speeds of 80 mph within about 5 seconds.
The deadliest avalanche in American history was due to a train wreck in 1910. Roughly 96 people died in the incident.
If a victim can be rescued within 18 minutes, the survival rate is greater than 91%. The survival rate drops to 34% in burials between 19 and 35 minutes.
After one hour, only 1 in 3 victims buried in an avalanche is found alive. The most common causes of death are suffocation, wounds, and hypothermia.
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There are two basic elements to an avalanche: a steep, snow-covered slope and a trigger that causes a weak layer within the snow pack to collapse. This video segment adapted from NOVA reveals that the shape of the ice crystals of snowflakes within a snow pack is also a critical factor.

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Avalanches happen when their is loose snow, a steep slope, a lot of snow, weak layer in the snow, and some kind of trigger such as skiers and snow mobiles, A few examples. They can happen when people cut down trees some people die from avalanches.

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If you're looking for the killer, then the slab avalanche is your man. This is the White Death, the Snowy Torrent, the Big Guy in the White Suit. Dry slab avalanches account for nearly all of the avalanche deaths in North America.

Wet Avalanches

Wet avalanches are triggered by warm air temperatures, sun or rain, causing water to percolate through the snowpack and decreasing its strength.

Most avalanche professionals make a hard separation between wet snow avalanches and dry snow avalanches, because they are so different. Much of their mechanics are different, they move differently, and it's only natural for us to think of them as two altogether separate beasts. But really there's a continuum between wet and dry avalanches.

Like dry snow avalanches, wet avalanches can occur as both sluffs and slabs. Wet avalanches usually occur when warm air temperatures, sun or rain cause water to percolate through the snowpack and decrease the strength of the snow, or in some cases, change the mechanical properties of the snow. Once initiated, wet snow tends to travel more slowly than dry snow-like a thousand concrete-carrying trucks dumping their loads at once, rather than the hovercraft-like movement of a dry avalanche.

A typical wet avalanche travels at 10 to 20 mph (15 to 30 km/h), but on steeper terrain they can go nearly as fast as a dry avalanche. Probably because not as many recreationists are out on wet snowy days, wet avalanches don't account for nearly as many avalanche fatalities as dry snow avalanches. However, they still account for a sizeable percentage of avalanche fatalities in maritime climates (mountains bordering oceans), especially to climbers.

Dry (Powder) Avalanches

Dry avalanches, though beautiful, are extremely violent and seize up like concrete the instant they come to a halt.

Dry avalanches are the stunningly beautiful ones that roar down the mountain, light and fluffy, like clouds of powder, but beneath the misty powder cloud is a rushing mass of snow-the "core" of the avalanche-that is a fluidized mix of air (70 percent) and ice particles (30 percent). As the snow rushes through the air it kicks up an envelope of powder, appropriately enough called a "powder cloud," which comprises only about one percent snow and 99 percent air, and this is the part of the avalanche that gives it its beauty.

In front of the powder cloud is the invisible "air blast" that pushes out in front of the moving snow. The air blast carries only about one tenth of the impact of the core, but it can travel fast enough to explode your lungs if you are caught by the full impact of the blast.

The avalanche is slowed down mainly by friction with the rocks, vegetation, and the snow surface it runs on. The snow nearest the bed travels more slowly than the snow above. Often, if you look close enough, you can see avalanches come down in waves. One wave shoots out, is slowed by friction with the ground and air, and then the next wave-travelling on the back of the first wave-shoots out ahead of the first wave, and so on. It looks like pulses of snow being spat out the front of the avalanche about once every few seconds.

The extreme violence inside the flowing debris grinds up all the snow into finer and finer particles, and even if the snow started out light and fluffy, it can become very dense by the time it finally comes to a stop. A large avalanche that starts out with a density of 5 to 10 percent (volume of snow versus air) can often end up as 30 to 40 percent at the bottom. This means that when everything comes to a stop, the dense snow packs very tightly.

Also, small grains sinter (coalesce) much more quickly than large grains, and the tiny grains making up avalanche debris can sinter as much as ten thousand times faster than the larger grains of the initial slab.

Finally, all of the kinetic energy liberated on the way down heats up the snow a little and creates small drops of liquid water on the surface of the ice grains. Combining all these factors, it's easy to see why avalanche debris seizes up like concrete the instant it comes to a stop. The avalanche victim is frozen in place.

Dry Slab Avalanches

Nearly all avalanche deaths in North America are caused by slab avalanches, caused when a cohesive plate of snow suddenly slides away.

A "slab" is a cohesive plate of snow that slides as a unit on the snow underneath. A slab doesn't have to be hard it just has to be relatively stronger than the snow underneath. A typical slab is about half the size of a football field, about one to two feet (30-60 cm) deep, and usually reaches speeds of 20 mph (32 km/h) within the first three seconds, quickly accelerating to around 80 mph (128 km/h) after the first, say, six seconds. The bonds holding a slab in place fracture at about 220 mph (352 km/h) and the slab appears to shatter.

Dry slab avalanches can lie teetering on the verge of catastrophe, sometimes for days or even months. The weak layers beneath the slabs are extremely sensitive and the rapid addition of the weight of just one person can easily initiate a fracture on a slope that would not have avalanched otherwise. A slope can sometimes be a giant booby trap-seemingly waiting for just the right person to come along. The crack often forms well above the victim, leaving little room for escape.

Loose Snow Avalanches

Loose snow sliding down a mountain is called a loose snow avalanche. Small loose snow avalanches are called "sluffs." Few people are killed by loose snow avalanches because they tend to be smaller, and they tend to fracture beneath you as you cross a slope, rather than above you, as slab avalanches often do. Most of the people killed in loose snow avalanches are climbers, or extreme skiers and boarders in very steep terrain.

Ice & Cornice Fall Avalanches

Ice and cornice fall avalanches occur when overhanging ice or snow breaks off.

When glaciers flow over a cliff they form the ice equivalent of a waterfall-an icefall. Falling blocks of ice can trigger an avalanche of ice, which often entrains snow below it, or triggers slabs. Especially in big mountains, ice avalanches can be large and travel long distances.

Despite this, ice avalanches kill few people compared to dry slabs that people trigger themselves. Most of the deaths from ice avalanches occur to climbers in big mountains who happen to be in the wrong place at the wrong time.

Cornices are the fatal attraction of the mountains, their beauty matched only by their danger. Cornices are elegant, cantilevered snow structures formed by wind drifting snow on to the lee (downwind) side of an obstacle, such as a ridgeline. Similar to icefall avalanches, the weight of a falling cornice often triggers an avalanche on the slope below, or the cornice breaks into hundreds of pieces and forms its own avalanche-or both.

Again like ice avalanches, statistically cornice fall avalanches don't kill very many people. And similar to slab avalanches, the skiers who get into trouble almost always trigger the avalanche, in this case by travelling too close to the edge of the cornice. Cornices have a nasty habit of breaking farther back than you expect. Never walk up to the edge of a drop-off without wearing a rope or first checking out the drop-off from a safe place.

Bruce Tremper and Mountaineers Books

Extracts and quotes reproduced from 'Staying Alive in Avalanche Terrain' by Bruce Tremper and reproduced with the kind permission of the publisher, The Mountaineers Books. The author Bruce Tremper Is the Director of the Forest Service Utah Avalanche Center and one of North America's foremost experts on avalanches. He has appeared in news reports and documentaries produced by National Geographic, PBS, and Discovery Channel, among others.

Related Articles

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If you're looking for the killer, then the slab avalanche is your man. This is the White Death, the Snowy Torrent, the Big Guy in the White Suit. Dry slab avalanches account for nearly all of the avalanche deaths in North America.

# data[].attributes.body
avalanches account for only a small percentage of deaths and property damage. “Slab” avalanches (the most lethal) are cohesive plates of snow sliding as a unit.
Each year avalanches kill more than 150 people worldwide.
In 90% of avalanche accidents, the victim or someone in the victim’s party causes the snow slide.
The human body is 3 times denser than avalanche debris and will sink quickly. When the slide slows, clear air space to breathe, then punch your hand skyward. Once the avalanche stops, it settles like concrete.
Unlike its portrayal in movies, noise does not trigger avalanches. Avalanches are caused by four factors: a steep slope, snow cover, a weak layer in the snow cover, and a trigger.
Tackle a campaign to make the world suck less.

EXPLORE CAMPAIGNS
The vast majority of avalanches (90%) occur on slopes with angles between 30 and 45 degrees. Steeper slopes tend to continually slough snow, keeping a deep snowpack from building up. The snowpack on flatter slopes requires more force to move.
Avalanche risk is at its greatest 24 hours following a snowfall of 12 inches or more.
Avalanches can reach speeds of 80 mph within about 5 seconds.
The deadliest avalanche in American history was due to a train wreck in 1910. Roughly 96 people died in the incident.
If a victim can be rescued within 18 minutes, the survival rate is greater than 91%. The survival rate drops to 34% in burials between 19 and 35 minutes.
After one hour, only 1 in 3 victims buried in an avalanche is found alive. The most common causes of death are suffocation, wounds, and hypothermia.
Sources
Tackle a campaign to make the world suck less.

EXPLORE CAMPAIGNS

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