Avalanche, a natural disaster
AVALANCHE KILLED PEOPLES IN LEH REGION
What’s in news?
An avalanche killed 5 persons and buries 2 vehicles in Leh region of Jammu & Kashmir.
- Avalanche is a natural disaster, kind of high velocity mass wasting event, the snow on the mountains falls on its sides suddenly due to gravity.
- It is hard to predict and mitigate.
- The main difference between the avalanche and landslides is;
- The avalanche is more homogenous consists only of snow mostly.
- Whereas, the landslides is heterogeneous comprised of soil, rocks of various size, earth layer. Both are due to mass wasting and high gravity.
- Avalanche is formed by the combination of loosening of snowpack (mechanical failure) and gravity (steepness, terrain, orientation of slope).
- The slope and the angle of repose are important for this avalanche formation.
- Snow avalanche is a mixture of both ice & associated debris like rock fragments, soil and vegetation.
- The snow avalanche is 2 types. They are
- Sluff: also known as loose snow avalanche, flow of small slide of dry, powdery snow as formless mass. This occurs in large and frequent but less harmful. This kind of avalanche originates at a point and grows wider.
- Slab avalanche: this kind of avalanche originates in snow with sufficient internal cohesion to enable snow layers to move as single entity. This occurs in less frequent but dangerous.
The difference between Avalanche, Blizzard, Hailstorm:
- Avalanche: It is swift movement of snow, ice, mud or mixture of them.
- Blizzard: It is very strong anf bitterly cold. Blizzard always accompanied with wind. This occurs in high altitude and in polar areas.
- Hailstorms: Sudden heavy fall of small hard balls of ice.