Boxing Day Tsunami / Indian Ocean Tsunami 2004

• When did the Boxing Day Tsunami occur?

  December 26, 2004
• What caused the 2004 Indian Ocean Tsunami?

  • A massive undersea earthquake with a magnitude of 9 off the coast of Sumatra, Indonesia, on December 26, 2004.
  • This earthquake occurred along the fault line where the Indian Plate slides beneath the Burma Plate, causing a sudden vertical displacement of the ocean floor.
  • The movement of tectonic plates displaced an immense volume of water, generating powerful tsunami waves that radiated across the Indian Ocean.
• What was the timeline of the Boxing Day Tsunami?

  1. The earthquake struck at 8 am local time. The initial tsunami waves reached the shores of Sumatra, Indonesia, within minutes.
  2. The waves propagated (spread) swiftly, reaching coastal areas of Thailand, Sri Lanka, India, and beyond over the following hours
  3. Ended up reaching a total of 14 countries
• How many people were displaced because of the tsunami? (secondary effect)

  Over 1.7 million
• What were the secondary effects of the Boxing Day Tsunami?

  • Disease outbreaks, spread of cholera, dysentery, and respiratory infections due to poor sanitation and overcrowded camps.
  • The tsunami and earthquake triggered landslides and volcanic activity in some areas.
  • Livelihood Loss: The fishing, agriculture, and tourism industries were devastated.
  • Saltwater Contamination: Farmland became infertile due to saltwater intrusion, impacting agriculture.
  • Coastal ecosystems like mangroves, coral reefs, and coastal forests were severely damaged, affecting fishing industries and biodiversity.
• How many people died due to the Tsunami? (primary effect)

  over 230,000 lives across the 14 countries.
• How many homes were destroyed and severely damaged due to the Tsunami? (primary effect)

  Over 500,000 homes, leaving millions homeless.
• Primary effects due to the Tsunami include:

  • Waves as high as 30 meters (100 feet) inundated coastal areas, causing massive flooding.
  • Freshwater supplies were contaminated by saltwater, debris, and corpses.
  • Costed $10 billion in damages.
• Factors worsening the effects:

  No tsunami warning system: The Indian Ocean region lacked an early warning system at the time, so coastal populations were unprepared.
• A factor worsening the effects of the Tsunami:


  No Evacuation Plans: Many communities had no protocols for evacuation, leaving people unaware of how to respond.
• A factor that worsened the effects of the Tsunami was:

  • Many of the affected areas, like Banda Aceh in Indonesia, were densely populated, increasing the death toll.
• A factor affecting the effect of the Tsunami:

  • Areas like Banda Aceh and Sumatra, just 20 minutes from the epicentre, were hit almost immediately, leaving no time to escape.
• • The tsunami affected over 14 countries, spreading resources and aid efforts thin, especially in the most devastated regions.
• • It struck early in the morning when people were sleeping or unprepared, particularly in Indonesia.
• What were some of the immediate, short-term responses to the Boxing Day Tsunami?

  • UN and NGOs provided food, water, blankets, and medicine to displaced populations.
  • Médecins Sans Frontières set up field hospitals to treat injuries and prevent disease outbreaks.
  • U.S. deployed 15,000 troops and naval ships to deliver aid and assist with logistics.
  • Indian and Sri Lankan military forces cleared debris and helped distribute supplies.
  • Thousands of bodies were buried in mass graves to prevent the spread of disease.
• • Immediate financial pledges included $350 million from the U.S., €450 million from the EU, and donations from countries like Japan, Canada, and Australia.
• What were some of the secondary, long-term responses for the Indian Ocean Tsunami?

  • Over $14 billion pledged globally to rebuild homes, roads, schools, and hospitals.
  • The Indian Ocean Tsunami Warning System was established in 2006 to detect seismic activity and issue alerts.
  • Tourism infrastructure, particularly in Thailand, was rebuilt to revive the economy.
  • Mangroves and coral reefs were replanted to act as natural barriers.
  • Coastal areas were zoned to avoid building in high-risk areas.
  • Communities were educated about tsunami risks, and evacuation drills were introduced.
• • Speed: Tsunami waves travelled at speeds of up to 800 km/h (500 mph) in the open ocean, giving little time for distant regions to prepare.
  • Height: Waves reached up to 30 meters (100 feet) in some areas, devastating everything in their path.
• • Area Covered: Waves travelled across the entire Indian Ocean, affecting coastlines as far as East Africa (Somalia), over 5,000 kilometres (3,100 miles) from the epicentre.