AVALANCHES AND THEIR MANAGEMENT STRATEGIES

D.Anitha TAM-2013-01

Dept. of Agronomy

What is an avalanche

Large mass of rock debris or snow that moves rapidly down a mountain slope, sweeping and grinding everything in its path.

An avalanche begins when a mass of material overcomes frictional resistance of the sloping surface, often after its foundation is loosened by spring rains or is rapidly melted by warm, dry wind. Vibrations caused by loud noises, such as thunder, or blasting can create an avalanche.

Avalanches usually occur in February, March, and January. They can also occur in April.

There are three different types of avalanches…..

1. A dry snow avalanche consists of powdery snow and air that can move faster than 100 MPH.

2. A wet snow avalanche is a mass of partially melted snow that moves slower than a dry snow avalanche.

3. A slab avalanche is when a portion of snow breaks loose as a slab and splits into pieces as it slides.

Avalanches can occur anywhere in the world.

They occur where ever there is a high snow covered mountain.

Avalanches can also occur near plate boundaries. Usually at convergent plate boundaries.

Avalanches don’t do a lot of damage to cities or towns because they are up in the high mountains . Avalanches burry mountain side homes and destroy forests. They also take down radio towers and lodges that are in its path. Avalanches also take away people’s lives, especially skiers who are taking a trip down the mountain.

Recent avalanche in IndiaJammu & Kashmir:

11 killed in avalanches, houses collapse on 12 march 2014.

Deaths From Avalanches

Avalanches cause a fair amount of deaths when they occur. They are so hard to predict and because of that people never know when they are going to happen. That is why it is best to never go onto a mountain alone.

How to prevent Avalanches

To prevent avalanches they build up snow fences to prevent buildup of snow in the starting-zones.

Also defecting walls are built up to divert avalanche flows away from buildings and even entire towns.

Sheds are also build across roadways that pass through persistent avalanche paths and they can help to protect motorists from avalanches.

Slopes with trees help to prevent avalanches as well. They use explosives to set off small avalanches in areas

that are of potential danger. This is to reduce the size of future avalanches in the risk area.

Snow Shield's Copper Armor Panel Snow Guard demonstrating snow retention on a copper roof.

Forest and structures to protect against avalanches.

Snow bridges in switzerland

Research is done to find out about the mechanisms that govern the build-up of snow - wind and precipitation - instability within the snow cover, and the flow of avalanches.

The main objective of this research is to improve zoning and make defences more effective and more reliable.