AVALANCHE (Syllabus: GS Paper 1 – Geography)

Context: Recently, following an extended dry period, Himachal Pradesh has seen substantial snowfall and rain over the past four days, resulting in an overall recorded 508 percent excess rain and snowfall, with incidents of avalanches reported in several districts of the state.

Avalanche

• About: It is a mass of material rapidly moving down a slope. 

oIt is typically triggered when the material on a slope breaks loose from its surroundings, and this material quickly collects and carries additional material down the slope.

• 4 Types of Avalanches: Loose Snow Avalanche, Slab Avalanche, Powder Snow Avalanche, and Wet Snow Avalanche.
• Causes of Avalanche: The probability of avalanches may be increased or decreased by several other terrain features, such as slope shape, a slope’s exposure to sun and wind, and elevation.
• Trigger Factors: Avalanches are commonly triggered by factors such as snowpack instability or sudden disturbances.
• Prone areas of avalanche: The snowy region of the Western Himalayas is particularly prone to avalanches. It includes higher areas in Jammu and Kashmir, Himachal Pradesh, and Uttaranchal.

Difference between avalanches and Landslides

• Environmental context: Landslides can transpire across diverse environments, triggered by factors like rainfall, earthquakes, or human intervention.
• Material Composition: Landslides comprise the movement of rock, earth, or debris down a slope or cliff.
• Triggered Factor: Landslides can be instigated by heavy rain, seismic activity, volcanic eruptions, or human alterations to the landscape.