hue1349 2012-02-09 21:45:58

Avalanche takes much life every year.

Avakanche is occured to a top layer than a bottom layer basically when I was stressful.

The snowslide can move at 300 kilometers/h, and several tons of snow can progress, too.

Oxygen disappears, and you suffocate if you are buried under the snow of several meters.

There are three causes of avalanche.

Mostly there are some snowy layers on the mountain.

The first layre of snow is called `bed layer'.

The next layer is a small grain of the ice.

The third layer is called the weak or slab layer.

A weak layer of snow lying on top of ice and bed layers means that an avalanche is more likely to occur.

A trigger needed for the slab layer of snow to slip off.

The pressure from the weight of the skier becomes the cause that the surface plate layer is easily broken.

The cause of avalanche affects the slope angle.

Most avalanches occur on slopes that have an angle of 25 to 60 degrees.

If the slop is greater than 60 degrees,the snow will constantly slide off,never allowing avalanche conditions to form.

According to statistics,slab avalanches account for 90 per cent of all ski fatalities.