On December 2004, tsunami brought havoc on 14 countries including India. Discuss the factors responsible for occurrence of Tsunami and its effects on life and economy. In the light of guidelines of NDMA (2010) describe the mechanisms for preparedness to reduce the risk during such events.

Introduction

A tsunami is a series of ocean waves caused by large-scale disturbances such as undersea earthquakes, volcanic eruptions, or landslides. The 2004 Indian Ocean tsunami, triggered by a 9.1 magnitude earthquake off the coast of Sumatra, devastated 14 countries, including India, causing over 2.3 lakh deaths and massive economic losses. This disaster underscored the need for robust preparedness and mitigation mechanisms.

Key Dimensions of Tsunami at a Glance

Factors Responsible for the Occurrence of Tsunami

• Undersea Earthquakes:

  • Most tsunamis are caused by subduction zone earthquakes where tectonic plates collide, displacing large volumes of water.
  • Example: The 2004 Indian Ocean tsunami was triggered by the Indo-Australian plate subducting beneath the Eurasian plate.

• Volcanic Eruptions:

  • Explosive eruptions or the collapse of volcanic islands can displace water.
  • Example: The 1883 Krakatoa eruption caused a massive tsunami.

• Underwater Landslides:

  • Landslides triggered by earthquakes or volcanic activity can generate tsunamis.
  • Example: The 1998 Papua New Guinea tsunami was caused by an undersea landslide.

• Meteorite Impacts:

  • Though rare, large meteorites striking oceans can create tsunamis.
  • Example: The Chicxulub impact (65 million years ago) likely caused massive waves.

Effects of Tsunami on Life and Economy

1. Impact on Life

• Loss of Lives:

  • The 2004 tsunami claimed over 2.3 lakh lives, with India losing over 10,000 people.
  • Coastal communities, especially in Tamil Nadu and the Andaman & Nicobar Islands, were severely affected.

• Displacement and Trauma:

  • Millions were displaced, leading to psychological trauma and loss of livelihoods.

2. Economic Impact

• Infrastructure Damage:

  • Ports, roads, and buildings were destroyed, disrupting trade and connectivity.
  • Example: The Port of Chennai suffered significant damage.

• Loss of Livelihoods:

  • Fishing and tourism industries were severely impacted.
  • Example: In Tamil Nadu, over 30,000 fishing boats were destroyed.

• Cost of Reconstruction:

  • The economic cost of the 2004 tsunami was estimated at $10 billion globally, with India bearing a significant share.

3. Environmental Impact

• Coastal Erosion:

  • Tsunamis erode beaches and destroy mangroves, coral reefs, and ecosystems.
  • Example: The Nicobar Islands saw extensive mangrove destruction.

• Salinization of Soil and Water:

  • Saltwater intrusion rendered agricultural lands infertile, affecting food security.

Mechanisms for Preparedness as per NDMA Guidelines (2010)

The National Disaster Management Authority (NDMA) issued comprehensive guidelines in 2010 to enhance tsunami preparedness. Key mechanisms include:

1. Early Warning Systems

• Indian Tsunami Early Warning Centre (ITEWC):
  • Established in Hyderabad, it monitors seismic activity and issues alerts within 10-20 minutes of an event.
• Real-Time Data Sharing:
  • Collaboration with global agencies like the Pacific Tsunami Warning Center ensures timely information dissemination.

2. Community Awareness and Capacity Building

• Public Awareness Campaigns:
  • Conducted in coastal areas to educate communities about evacuation routes and safety measures.
• Mock Drills:
  • Regular drills to test preparedness and response capabilities.

3. Coastal Zone Management

• Mangrove Restoration:

  • Mangroves act as natural barriers, reducing the impact of waves.
  • Example: Post-2004, mangrove plantations were promoted in Tamil Nadu.

• Regulation of Coastal Development:

  • Enforcing the Coastal Regulation Zone (CRZ) norms to prevent unplanned construction in vulnerable areas.

4. Infrastructure Development

• Resilient Infrastructure:
  • Construction of tsunami shelters and elevated platforms in vulnerable regions.
• Sea Walls and Dykes:
  • Example: Japan’s extensive sea walls to mitigate tsunami impact.

5. Post-Disaster Response

• Search and Rescue Teams:
  • Deployment of National Disaster Response Force (NDRF) for immediate relief operations.
• Rehabilitation and Reconstruction:
  • Focus on building back better with disaster-resilient infrastructure.

Way Forward

• Strengthening Regional Cooperation:
  • Enhanced collaboration with Indian Ocean Rim countries for data sharing and joint drills.
• Leveraging Technology:
  • Use of AI and satellite-based systems for real-time monitoring and prediction.
• Community-Led Initiatives:
  • Empowering local communities to take ownership of disaster preparedness measures.

Conclusion

Tsunamis, though rare, have catastrophic impacts on life, economy, and the environment. By adhering to the NDMA guidelines (2010) and fostering a culture of preparedness, India can significantly reduce the risks associated with such events. A multi-stakeholder approach, combining technology, community participation, and regional cooperation, is essential to build resilience against future tsunamis.