Avalanche
Kartavya Desk Staff
Syllabus: Disaster Management
Source: IE
Context: A massive avalanche struck a BRO project site near Mana village in Chamoli district, Uttarakhand, trapping 22 workers under ice, with ongoing rescue operations by the Indian Army and ITBP.
About Avalanche:
What is an Avalanche?
• A sudden and rapid descent of snow, ice, and debris down a mountain slope, triggered by natural or human-induced factors.
• Can cause widespread destruction by burying people, structures, and transport routes under tons of snow.
Types of Avalanches:
• Loose Snow Avalanche: Forms when loosely bonded snow starts sliding from a single point. Common in steep slopes (>40°) with fresh snowfall.
• Forms when loosely bonded snow starts sliding from a single point.
• Common in steep slopes (>40°) with fresh snowfall.
• Slab Avalanche: Occurs when a cohesive layer of snow breaks away as a single slab. Responsible for most fatalities, reaching speeds of 100 km/h.
• Occurs when a cohesive layer of snow breaks away as a single slab.
• Responsible for most fatalities, reaching speeds of 100 km/h.
• Gliding Avalanche: Involves entire snowpack sliding over a smooth surface (grass, rock). Occurs at slopes >15° and leads to large-scale destruction.
• Involves entire snowpack sliding over a smooth surface (grass, rock).
• Occurs at slopes >15° and leads to large-scale destruction.
• Powder Avalanche: High-speed avalanches suspending snow particles in air, creating a powder cloud. Can reach speeds of 300 km/h, causing severe shockwave impact.
• High-speed avalanches suspending snow particles in air, creating a powder cloud.
• Can reach speeds of 300 km/h, causing severe shockwave impact.
• Wet Snow Avalanche Triggered by melting snow due to temperature rise or rain. Slower but more destructive due to its high density and force.
• Triggered by melting snow due to temperature rise or rain.
• Slower but more destructive due to its high density and force.
Causes of Avalanches
• Natural Causes:
• Heavy Snowfall & Wind Direction: Unstable snowpack due to uneven accumulation.
• Steep Slopes: Avalanches commonly occur at 30°-45° inclinations.
• Temperature Fluctuations: Melting snow weakens internal layers, increasing instability.
• Earthquakes & Vibrations: Trigger snow movement on unstable slopes.
• Human-Induced Causes:
• Winter Sports & Tourism: Skiing, snowmobiling, and trekking destabilize snow layers.
• Construction & Deforestation: Removal of trees weakens slope stability.
• Military Operations: High-altitude warfare and detonations can trigger slides.
Consequences & Impact of Avalanches:
• Loss of Life & Injuries: Avalanches cause suffocation, hypothermia, and fatal trauma, with survival chances dropping significantly after 15 minutes of burial.
• Destruction of Infrastructure: Snow slides block roads, railways, and highways, cutting off access and burying homes, BRO camps, and tourist shelters under heavy snow.
• Disruptions in Communication & Utilities: Avalanches damage power lines, water supply, and communication networks, delaying rescue operations and emergency responses.
• Environmental Hazards: Melting avalanche snow can trigger landslides and flash floods, leading to severe ecological damage and displacement of local communities.
• Economic Impact: Avalanches cripple winter tourism, disrupt livelihoods, and result in economic losses, requiring huge recovery costs for damaged infrastructure and services.
Precautionary & Control Strategies:
• Avalanche Early Warning Systems:
• IMD Avalanche Forecasting: Tracks snowfall, slope stability, and temperature fluctuations.
• Remote Sensing & AI-Based Prediction Models: Used for real-time avalanche detection.
• Structural Protection Measures:
• Snow Barriers & Fences: Installed on avalanche-prone slopes to prevent snow buildup.
• Deflecting Structures: Direct the avalanche path away from inhabited zones.
• Artificial Avalanche Triggers:
• Controlled Explosions: Initiates small avalanches to prevent larger, unmanageable ones.
• Zoning & Land Use Planning
• Avoidance of Construction in Avalanche-Prone Areas.
• Ski Resorts & Highways Must Follow Risk Assessment Reports.
Way Ahead:
• Enhancing Real-Time Avalanche Forecasting: Strengthening satellite-based avalanche monitoring systems for early warnings.
• Improving Infrastructure Resilience: Constructing avalanche protection tunnels and snow-retention fences along highways.
• Stronger Coordination Between Agencies: Integrating IMD, BRO, NDMA, and ITBP efforts for better disaster response.
• Community Training & Awareness Programs: Educating local residents, trekkers, and military personnel on avalanche survival skills.
• Encouraging Climate-Resilient Development: Limiting deforestation and unplanned construction in high-risk zones.
Conclusion:
Avalanches pose a significant threat in India’s Himalayan region, impacting human lives, infrastructure, and economic activities. Advanced forecasting, structural protection, and rescue preparedness are critical for minimizing avalanche disasters. Strengthening inter-agency collaboration and public awareness will further enhance India’s avalanche resilience.
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