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` ³An Avalanche is a flow of snow down

a mountain side through rock slides´ 

` They are flows which move under the influence of gravity

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` Temperatur e: Changes that last several hours or 

days, such as a warm front moving through can

seriously weaken some of the upper layers of snow.

` Snow Pack Conditions: Understanding the history of 

snow pack for that season can reveal several clues

about slope stability. Snow pack conditions can

change not only over the course of the winter season

but over the course of a day. This is why constant

awareness and frequent slope testing are necessary.

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` Slope Angle: Most avalanches occur on slopes

between 30 and 45 degrees.

` Wind Dir ection: Wind usually blows up one side

of the slope of the mountain(the windward side),

and down the other(the leeward side). When

blowing up the windward side, wind will scour 

snow off the surface and drop it on the leeward

side.

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` Powder snow Avalanche:

`  As avalanches move down the slope they may

entrain from the snow pack and grow in size. The

snow may mix with the air and form a powder cloud. An avalanche with a powder cloud is know

as a powder snow avalanche.

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Loose Snow Avalanche

Ice Fall Avalanche

Cor nice Fall Avalanche

Slab Avalanche

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`  An avalanche beacon, also known as an

avalanche transceiver, is a device that is worn

across the chest above the base layer of clothing,

and that transmits a signal which other avalanchebeacons can receive. In the event of a slide, other 

people can switch their beacons from transmit to

receive, and can begin a search for the person

stranded in the avalanche. These devices canquickly cut down the time needed to find someone

in the snow and digging them out.

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` To help reduce avalanches from forming:

` use of terrace

` use of supporting structures

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` These are placed

directly in front of asingle object

` They redirect and

divert the avalancheflow around the

structure

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Use of 

splitters onski slopes

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` These are used to

retard flowing snow

at the end of the

runout zone

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Detail of mounds

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` These sheds allow

the avalanche to

pass over the

structure