Tohoku Earthquake - Japan

• When did the Great Tōhoku hit Japan?


  Struck northeastern Japan on March 11, 2011 at 2.40pm
• The tsunami began hitting the coast within 30 minutes after the quake.
• The tsunami affected the whole world by making days 1.8 milliseconds shorter. As it shifted the earths axis 10-25 cm
• What caused the Great Tōhoku earthquake in 2011?

  • Occurred at the Japan Trench, a subduction zone where the pacific plate is being forced beneath the North American Plate
  • This subduction zone is part of the ring of fire.
  • The earthquake was a megathrust event caused by the sudden release of strain accumulated over centuries in the subduction zone
• This event was the 4th largest earthquake globally since 1900 and the largest ever recorded in Japan.
• What caused the tsunami?

  After the 9.0 underwater earthquake occurred in the Pacific Ocean, 400-500 km of the North American plate moved upwards, causing the tsunami.
• Japan experiences frequent earthquakes, with 1,500 recorded annually, leading to a general acceptance of their occurrence. Meaning people are less shocked but instead better prepared.
• Context for The Great Tōhoku:

  • Occured in early spring with winter conditions still lingering
  • Hit a densely populated area where places are overcrowded
  • The region had a nuclear power plant that was hit by the tsunami.
• Scale:


  1. The earthquake lasted around 6 minutes, causing widespread ground shaking that was felt across much of Japan.
  2. The energy released was equivalent to approximately 600 million times the energy of the Hiroshima atomic bomb, demonstrating its immense power.
  3. Weeks after the original earthquake, there were over 700 aftershocks.
• The earthquake triggered a devastating tsunami, with waves reaching heights of over 40 meters (131 feet) in some areas and travelling up to 10 kilometres (6 miles) inland.
• Social impacts of the event include:

  • In Minami-Sanriku, approximately half the population died (8500)
  • Approximately 18,000 people died or are still missing
  • 950,000 left homeless
  • 1 million homes left without clean water and 6 million left without electricity
  • Severe psychological trauma and long-term mental health challenges for survivors.
  • A shift in public attitudes towards nuclear energy, leading Japan to reduce its reliance on nuclear power
• What were the economic impacts of The Great Tōhoku, 2011?

  1. Estimated cost of damages: $235 billion
  2. Destruction of businesses and loss of productivity, particularly in the Tohoku region.
  3. Disruption of global supply chains, particularly in the automotive and electronics industries.
  4. Buildings collapsed, and some set alight due to broken gas pipes.
• What were the environmental impacts of the Great Tōhoku earthquake?

  • The tsunami caused the Fukushima nuclear disaster, leading to radiation leaks and long-term environmental contamination.
  • Destruction of marine ecosystems and significant debris deposited in coastal and marine environments.
  • Loss of forested and agricultural land due to saltwater intrusion (salinisation) and debris.
• • Over 120,000 buildings were destroyed and nearly 300,000 were partially damaged.
• • Transportation networks (roads, railways, and ports) were severely damaged, including Sendai Airport.
  • Power outages affected millions, with rolling blackouts continuing for months.
  • Extensive damage to water and sewage systems, leaving communities without basic utilities.
• Perceptions of earthquakes before the Great Tōhoku:

  • The region experiences 1500 smaller earthquakes a year; the people that continue to live there practice the theory of acceptance and fatalism.
  • Main religion is Buddhism, and the religion believes that karma is real and that everything is predetermined
  • Children are taught to run underneath tables and put on a helmet when they feel shaking, showing they have accepted they live in an area with a high frequency of earthquakes.
  • Tsunami warning systems show how they are prepared and know that they are under threat constantly (acceptance).
• What were some of the immediate responses to the event?

  • Over 100,000 members of the Japanese Self-Defence Forces (JSDF) were deployed to assist in search, rescue, and recovery efforts.
  • Large-scale evacuations in coastal areas, as well as an exlusion zone in the vicinity of the Fukushima Daiichi Nuclear Plant, due to radiation risks.
  • Around 450,000 people relocated to emergency shelters, including schools, community centers, and stadiums
  • Over 163 countries and several international organisations offered aid, including rescue teams, financial support, and supplies
• • International aid, including funds from China and the USA, helped rebuild lives quickly. The UK sent 63 rescue workers, two dogs, and a medical team, saving trapped survivors through specialised efforts.
• • Remarkably, there were no reports of looting or violence, reflecting a focus on survival, gratitude, and mutual aid amidst widespread destruction. (cultural factor)
• What were the long-term responses to the event?

  • The government formed the Reconstruction Design Council to drive Tōhoku's recovery. Special Zones for Reconstruction offered relaxed planning rules and tax incentives to encourage swift rebuilding and economic growth.
  • In 2013, Japan introduced an upgraded tsunami warning system to help people assess risks accurately and evacuate safely.
  • Before 2011, nuclear power supplied 30% of Japan's electricity. Anti-nuclear actions delayed reactor restarts until 2016, forcing reliance on fossil fuels.
• • The earthquake had minimal impact, but the tsunami caused severe damage due to inadequate defences. Japan is now planning better coastal protection for rare but powerful events to reduce casualties and injuries.