A powerful undersea earthquake that struck off the coast of Sumatra island, Indonesia, set off the 2004 Indian Ocean tsunami, also known as the Christmas or Boxing Day tsunami, on Sunday morning, Dec. 26, 2004. The magnitude 9.1 quake ruptured a 900-mile stretch of fault line where the Indian and Australian tectonic plates meet. It was a powerful megathrust quake, occurring where a heavy ocean plate slips under a lighter continental plate.
The quake caused the ocean floor to suddenly rise by as much as 40 meters, triggering a massive tsunami. Within 20 minutes of the earthquake, the first of several 100-foot waves hit the shoreline of Banda Aceh, killing more than 100,000 people and pounding the city into rubble. Then, in succession, tsunami waves rolled over coastlines in Thailand, India, and Sri Lanka, killing tens of thousands more. Eight hours later and 5,000 miles from its Asian epicenter, the tsunami claimed its final casualties on the coast of South Africa. In all, nearly 230,000 people were killed, making it one of the deadliest disasters in modern history.
Since the 2004 tsunami, governments and aid groups have prioritized disaster risk reduction and preparedness. Only three weeks after the tsunami, representatives of 168 nations agreed to the Hyogo Framework for Action, which paved the way for global cooperation for disaster risk reduction. Since then, ocean floor earthquake sensors have been installed to trigger early warnings, and many local communities have been trained in evacuation and disaster response.
Major earthquakes and tsunamis in August and September 2018 have tested Indonesia’s ability to respond and recover. Then, in December 2018, Anak Krakatau volcano’s ongoing eruptions in the Sunda Strait caused undersea landslides that triggered a tsunami that struck beaches in both Sumatra and Java. With no warning triggered by the volcanic activity, more than 400 people died. Now, the Indonesian government is working to add volcano sensors to its warning systems.
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FAQs: What you need to know about the 2004 Indian Ocean tsunami
Explore facts and frequently asked questions about the 2004 Indian Ocean earthquake and tsunami, and learn how you can help survivors of disasters.
- Fast facts: 2004 Indian Ocean earthquake and tsunami
- How many people died in the 2004 Indian Ocean earthquake and tsunami?
- Why was the 2004 Indian Ocean tsunami so destructive and deadly?
- Where did the earthquake hit?
- How big was the earthquake that caused the Indian Ocean tsunami?
- How can I help people affected by earthquakes and tsunamis?
- How did World Vision help people recover from the 2004 Indian Ocean earthquake and tsunami?
- How does World Vision help people prepare for disasters?
- 2004 Indian Ocean earthquake and tsunami timeline
Fast facts: 2004 Indian Ocean earthquake and tsunami
- The Sumatra-Andaman earthquake, which caused the 2004 Indian Ocean tsunami, is estimated to have released energy equivalent to 23,000 Hiroshima-type atomic bombs.
- In Banda Aceh, the landmass closest to the quake’s epicenter, tsunami waves topped 100 feet.
- The tsunami’s waves traveled across the Indian Ocean at 500 mph, the speed of a jet plane.
- The 2004 Indonesia earthquake caused a shift in the Earth’s mass that changed the planet’s rotation.
- Total material losses from the tsunami were estimated at $10 million.
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How many people died in the 2004 Indian Ocean earthquake and tsunami?
Nearly 230,000 people died in the 2004 Indian Ocean earthquake and tsunami, making it one of the deadliest disasters in modern history.
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Why was the 2004 Indian Ocean tsunami so destructive and deadly?
The first giant waves from the Indian Ocean tsunami reached Banda Aceh, a city of about 300,000 people within 15 or 20 minutes after the earthquake. Few residents of the densely populated area realized that the earthquake they had felt could cause a tsunami, and there was little time to flee to higher ground.
Traveling as fast as 500 mph, the waves spread out to distant countries including Thailand, Sri Lanka, and India. With no warning, coastal populations were caught by the pounding waves. Many families that made their living fishing lost everything; whole communities were wiped out by the tsunami.
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Where did the earthquake hit?
The Sumatra-Andaman earthquake struck 150 miles from the coast of Sumatra island, on the northwest of the Indonesian island group, and 31 miles below the ocean floor. The quake occurred along a fault line between the Indian tectonic plate and the Burma microplate, part of the Australian plate. The Indian plate is a heavy ocean plate, and it slipped under the lighter coastal plate, rupturing a 900-mile length of the fault.
Indonesia lies between the Pacific Ring of Fire, where 90% of earthquakes occur, and the second-most active seismic zone, the Alpide belt.
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How big was the earthquake that caused the Indian Ocean tsunami?
The earthquake’s magnitude was measured between 9.1 and 9.3, making it the third-most powerful quake since 1900. Magnitude is a measure of the release of energy at the earthquake’s source.
In the worst-affected areas, the quake’s intensity rated IX on the Mercalli scale, the second highest rating possible. So the quake caused violent shaking and extensive damage to even well-built buildings. Earthquake intensity is based on observation and varies in different places.
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How can I help people affected by earthquakes and tsunamis?
- Give: Donate to World Vision’s disaster relief fund to bring help when another disaster strikes.
- Pray: Join us in praying for families as they recover and rebuild after earthquakes and other disasters: Almighty Father, we ask for Your caring mercy on people hard hit by natural disasters, including earthquakes and tsunamis. In the midst of their struggle to recover, give them patience, peace, and hope that their lives will continue to improve.
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How did World Vision help people recover from the 2004 Indian Ocean earthquake and tsunami?
In response to the 2004 Indian Ocean earthquake and tsunami, World Vision mounted its largest-ever relief response across five countries simultaneously — Indonesia, Sri Lanka, Thailand, India, and Myanmar — and raised more than $350 million.
World Vision focused on the needs of children, families, and their communities, with programs to provide protection, healthcare, education, and livelihoods. We provided training and employment opportunities to 40,000 people, child-rights awareness sessions for more than 27,000 people, educational support for more than 2,000 teachers and 137,000 children, and implemented community-level disaster risk reduction programs.
World Vision built 12,000 homes, 200 Child-Friendly Spaces, 84 schools, 60 playgrounds, and 27 health clinics. We built roads, bridges, farms, factories, marketplaces, boat-building centers, and restored a fishing harbor.Our coastal restoration programs included planting 56,000 mangroves to serve as a natural barrier to rising ocean levels.
Most tsunami-related rehabilitation work was completed by 2007. Today, World Vision’s expansive child sponsorship, health, education, water, food, agriculture, and income-generating activities are found across each of the tsunami-affected countries.
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How does World Vision help people prepare for disasters?
World Vision pre-positions relief supplies and trains staff for emergency work in areas like child protection, relief supply chain management, clean water provision, and more. In disaster-prone communities where we work, we organize programs to reduce risks from disasters and train local first responders.
In nearly 100 countries around the world, World Vision works to improve the lives of children and families and to help them prepare for and recover from disasters.
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2004 Indian Ocean earthquake and tsunami timeline
December 26, 2004
- 7:58 a.m.: A magnitude 9.1 earthquake occurs off the northwest coast of Sumatra.
- +15 minutes: The Pacific Tsunami Warning Center in Hawaii registers the quake.
- +20 to 30 minutes: Tsunami waves more than 100 feet high pound the Banda Aceh coast, killing about 170,000 people and destroying buildings and infrastructure.
- +1.5 hours: Beaches in southern Thailand are hit by the tsunami. Among the 5,400 who died were 2,000 foreign tourists.
- +2 hours: The tsunami strikes the Sri Lankan coastline from the northeast and all around the southern tip; more than 30,000 people are dead or missing. The east coast of India is hard hit from Chennai south; more than 16,000 people are killed.
- +8 hours: The tsunami reaches the east coast of Africa, killing more than 300 people in Somalia, Tanzania, and Kenya.
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Learn more about earthquakes and tsunamis, which are among the most damaging and deadly disasters.
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FAQs
What was done to help after the 2004 tsunami? ›
The aid response to the 2004 Indian Ocean tsunami was unprecedented for a natural disaster, with a colossal $6.25bn donated to a central UN relief fund assisting 14 countries. The series of tsunamis on 26 December 10 years ago killed more than 228,000 people and left more than 2 million people homeless.
How did the community help in the 2004 tsunami? ›In addition to providing immediate help for things like water, food, clothing and shelter, over time assistance programmes provided work opportunities as well as funds and materials to rebuild houses, schools, health facilities, community centres, mosques, roads and other infrastructure.
Who helped with the 2004 Indian Ocean tsunami? ›UNICEF was on the ground in the affected region at the time of the tsunami disaster and went to work immediately to provide lifesaving humanitarian relief to the survivors. Teams were mobilized in eight countries — Indonesia, Thailand, Myanmar, Malaysia, Sri Lanka, the Maldives, India and Somalia.
How should we prepare for disasters like the 2004 Indian Ocean tsunami? ›The disaster risk reduction includes delivery of tsunami early warning messages to officials and coastal residents, making tsunami hazard maps or probabilistic hazard assessments, construction of infrastructure such as speakers to disseminate the warning messages, seawalls, evacuation signs, and designated evacuation ...
How does the government help after a tsunami? ›Federal disaster relief agencies like FEMA provide food, shelter, water, money, and healthcare for those affected by a natural disaster.
Who saved many lives when tsunami struck? ›Tilly Smith (born 1994) is an English woman who has been credited with saving the lives of about 100 beachgoers at Mai Khao Beach in Thailand by warning them minutes before the arrival of the tsunami caused by the 2004 Indian Ocean earthquake.
Who was saved in the tsunami? ›Solution : Meghna was saved by a relief helicopter. Almas's father realised that a tsunami was going to hit the island. Her mother and aunts were washed away with the tree that they were holding on to.
Who helped Japan during tsunami? ›Several countries, including Australia, China, India, New Zealand, South Korea, and the United States, sent search-and-rescue teams, and dozens of other countries and major international relief organizations such as the Red Cross and Red Crescent pledged financial and material support to Japan.
What 5 things can you do to prepare for a tsunami? ›- Check your house and land for any potential dangers related to flooding.
- Identify any vulnerability and repair it.
- Learn how to turn off the gas and electricity in your house. ...
- Do not store your important documents in the basement. ...
- Ensure that your family has an emergency kit and plan.
- Map of area showing an agreed meeting spot in case of separation and the nearest safe shelter.
- Family and emergency contact information.
- Basic first aid kit.
- Water and non perishable food (three to seven day supply)
- Flashlight.
- Battery powered radio.
What countries helped the Indian Ocean tsunami? ›
By 1 January 2005 over US$1.8 billion (£1bn) had been pledged. In wake of the disaster, Australia, India, Japan and the United States formed a coalition to coordinate aid efforts to streamline immediate assistance.
How many people became homeless in the 2004 tsunami? ›According to Oxfam, five million people were affected of which 1.7m were made homeless, half a million were injured and more than 230,000 were killed.
How many people were left homeless after the 2004 tsunami? ›Tsunami of 2004, caused by a 9.0 magnitude earthquake, is the most devastating tsunami in modern times, affecting 18 countries in Southeast Asia and Southern Africa, killing more than 250,000 people in a single day, and leaving more than 1.7 million homeless.
How can we prevent earthquakes and tsunamis? ›We cannot prevent natural earthquakes from occurring but we can significantly mitigate their effects by identifying hazards, building safer structures, and providing education on earthquake safety. By preparing for natural earthquakes we can also reduce the risk from human induced earthquakes.
How can I help others affected by disasters? ›- Donate food or other items. Check with your local Red Cross chapter, community center (like the YMCA), or place of worship to find out what they need. ...
- Donate your time. Offer to help sort through donations or deliver goods to families affected by the disaster.
- Organize a fundraiser.
Within five years, individuals were back in homes they owned, often on their original land, in communities with new schools and in many cases improved infrastructure.
How does the government help after an earthquake? ›When the president declares an area struck by an earthquake to be a major disaster area, FEMA swings into action. A coordinating officer is appointed, who sets up a disaster field office to manage the response and recovery, including rescue and small loans and grants to businesses or individuals.
What help was given to Japan after the tsunami? ›Several countries, including Australia, China, India, New Zealand, South Korea, and the United States, sent search-and-rescue teams, and dozens of other countries and major international relief organizations such as the Red Cross and Red Crescent pledged financial and material support to Japan.
How did the US help Japan after the 2011 tsunami? ›Within 24 hours of the earthquake, following a late-night phone conversation between then Prime Minister Naoto Kan and President Barack Obama, U.S. military forces began their largest-scale disaster relief and rescue operations with the Japanese Self-Defense Forces through Operation Tomodachi -- "Operation Friend."
Who helps after a tsunami? ›Call the National Response Center 800-424-8802 (24 hours a day every day). For those without 800 access, please call 202-267-2675. Industries and businesses that encounter spills or discharges in the aftermath should contact the National Response Center immediately.
What has Japan done to prevent tsunamis after 2011? ›
Now, Japan has a network of early warning instrumentation systems to sense earthquakes on the ocean floor, the New York Times reported. They've built seawalls to protect against tsunamis in some of their coastal cities. And the people there are learn early how to react in case of earthquakes and tsunamis.
How did the US help Japan recover? ›After World War II, the United States also understood the strategic importance of using foreign assistance and other tools to aid and rebuild post-war Japan. Between 1946 and 1952, Washington invested $2.2 billion — or $18 billion in real 21st-century dollars adjusted for inflation — in Japan's reconstruction effort.
How much did it cost to repair Japan after the tsunami? ›Japan's Tsunami and Nuclear Disaster Unleashed a $300 Billion Effort to Rebuild a Hinterland.
How many countries helped Japan tsunami? ›Following the 2011 Tōhoku earthquake and tsunami, Japan received messages of condolence and offers of assistance from a range of international leaders. According to Japan's foreign ministry, 163 countries and regions, and 43 international organizations had offered assistance to Japan as of September 15, 2011.
What did the US do to stop Japan? ›The U.S. Was Trying to Stop Japan's Global Expansion
In light of such atrocities, the United States began passing economic sanctions against Japan, including trade embargoes on aircraft exports, oil and scrap metal, among other key goods, and gave economic support to Guomindang forces.
Much of Japan's northeastern coastline hit by the tsunami has been fortified with enormous concrete seawalls as high as 15 meters (50 feet). All of the walls have been completed except for sections of the eastern coast of Fukushima. When completed, the total length will be 432 kilometers (270 miles).
Did the US give aid to Japan? ›The Treaty of Mutual Cooperation and Security between Japan and the United States was signed in 1960. The United States provides no development assistance to Japan.
How do people rebuild after a tsunami? ›A popular approach is to build a core house; a small, well-constructed, disaster resilient structure that can be extended and expanded as a family's circumstances and finances allow. Habitat has successfully used the core house model after the 2004 Indian Ocean tsunami, and following an earthquake in Indonesia in 2009.
Can tsunamis be prevented or stopped? ›Tsunamis, like most natural disasters, are beyond human control. There are, however, a number of techniques that can minimize the harmful effects of tsunamis to the physical environment (including built structures) and to individuals and communities.
How long did it take to clean up the 2011 tsunami? ›Has Japan recovered from the 2011 earthquake and tsunami? In July 2011, the Japanese government set a 10-year timeline for recovery with specific targets for clearing debris, restoring infrastructure, and housing. So far, nearly all of the debris from the earthquake and tsunami has been recycled or incinerated.
What has Japan done to prevent floods? ›
Japan employs underground spaces to ready urban areas for otherwise catastrophic flooding. Massive underground spaces, such as this one, below the ring roads that run through major residential areas are critical elements of flood control in Tokyo.