The Great Tohoku earthquake, also known as the 2011 Tohoku earthquake and the Great Tohoku earthquake, was a natural disaster that shook northeastern Japan on March 11, 2011. The disaster began when a magnitude-9 earthquake shook the region in the afternoon.

The effects of the great earthquake in Japan were felt all over the world, from the fjords in Norway to the ice sheet in the South Pole. There are still debris on North American beaches.

The people of Japan are still recovering from the disaster. There are 39,000 evacuees who lost their homes and 1,000 who are still living in temporary housing, according to Japan's Reconstruction Agency.

More than one million buildings were destroyed, half of them partially destroyed, according to the agency. According to the Japanese government, the direct financial damage from the disaster is estimated to be about 19 trillion dollars. The World Bank estimated that the economic cost could be as high as $235 billion, making it the costliest natural disaster in history.

Japan was hit by an earthquake in 2011.

This map shows the travel times of the tsunami generated by the Honshu earthquake on March 11, 2011.

This map shows the travel times of the tsunami generated by the Honshu earthquake on March 11, 2011. (Image credit: NOAA/NWS)

The unexpected disaster was not the largest or the worst earthquake to hit this century. The largest earthquake in history happened in Sumatra in 2004, killing more than 230,000 people. Few scientists had predicted that Japan would experience a large earthquake and a wave.

Japan's scientists had predicted a small earthquake would hit the northern region of Honshu, the country's main island. They didn't expect such a large wave. There were hints of the disaster to come. The areas that were flooded in 2011 were close to the areas that were hit by a wave. In the decade before the Tohoku earthquake, a handful of Japanese geologists began to recognize that a large earthquake had struck the northern Honshu region. Live Science previously reported that their warnings went unheeded by officials responsible for the country's earthquake hazard assessments. To better predict the country's future earthquake risk, experts from around the world have been asked to assess the history of past tsunamis in Japan.

The Center for Tsunami Research in Seattle, Washington told Live Science that a big earthquake will cause the most damage. There were human lives lost in Sumatra and Japan. It is about 10 times less.

A map showing the shaking intensity of the 2011 Tohoku earthquake. Darker red circles represent higher intensity tremors.

A map showing the shaking intensity of the 2011 Tohoku earthquake. Darker red circles represent  higher intensity tremors. (Image credit: NASA Earth Observatory)

The 2011 Tohoku earthquake

The Tohoku earthquake struck off of Japan, along a subduction zone. One plate slides beneath another into the mantle in a subduction zone. The great plates build up energy that is released as earthquakes. The Pacific plate dives beneath the Eurasian plate. A recent study found that the temblor completely released the built up stress between the two plates.

The earthquake began on Friday at 2:46 p.m. The time is UTC. 45 miles east of Tohoku, it was centered at a depth of 24 km below the surface. The shaking lasted about six minutes.

The scientists discovered a thin, slippery clay layer on the fault after drilling into the subduction zone. The researchers think that the two plates were able to slide an incredible distance because of the clay layer.

Early warning

The residents of Tokyo received a minute of warning before the strong shaking hit the city. High-speed trains and factory assembly lines were stopped because of the country's strict earthquake building codes. People in Japan received warnings of the earthquake on their cellphones.

Death toll of the 2011 earthquake and tsunami

According to the reconstruction agency, the number of confirmed deaths is 19,747. More than 2,500 people are reported missing.

Less than an hour after the earthquake, the first waves hit Japan. The waves traveled inland as far as 10 km from Miyako city and reached run-up heights of up to 128 feet. An estimated 217 square miles of Japan was flooded by the wave.

The seawalls at several locations were destroyed by the waves. The buildings where people had gathered for safety were destroyed by the surge. A huge whirlpool is captured on video near Oarai.

The cooling system failure at the Daiichi Nuclear Power Plant resulted in a level-7 nuclear meltdown and release of radioactive materials. The electrical power and backup generators were overwhelmed by the wave.

The tsunami created Fukushima. The earthquake was not a factor.

The North American coast has low levels of radioactive chemicals that leaked from Japan.

Houses above the inundation zone in this Japanese village survived intact, while everything below was destroyed by the 2011 tsunami.

Houses above the inundation zone in this Japanese village survived intact, while everything below was destroyed by the 2011 tsunami. (Image credit: Patrick Corcoran, Oregon State University)

The response

Japan's Meteorological Agency was criticized for issuing a warning that underestimated the size of the wave. The Japanese government studied the aftermath of the earthquake and found that only 42% of people headed for higher ground. The study found that many people underestimated their personal risk or assumed the tsunami would be smaller than they had previously experienced.

Scientists from all over the world descended on Japan. The forces that caused the earthquake were measured by the researchers. The teams studied the deposits to better understand the history of the waves. Earthquake engineers looked for ways to build buildings that were more resistant to earthquakes.

The effects in Japan will be there for a long time, according to Titov.

Worldwide effects

The waves traveled across the Pacific. When the wave reached the shore in Chile, it was over 6 feet high, according to the warning center.

Weird Earth movement after Japan earthquake was finally explained.

5 million tons of debris were carried out to sea by the surge of water. Japanese docks and ships have arrived in the US and Canada in the ensuing years. The Coast Guard sank the boat in the Gulf of Alaska in 2012 after firing on it. The ship left Hokkaido.

Amazing facts

There are some amazing facts about the Japan earthquake.

  • The earthquake shifted Earth on its axis of rotation by redistributing mass, like putting a dent in a spinning top. The temblor also shortened the length of a day by about a microsecond.
  • More than 5,000 aftershocks hit Japan in the year after the earthquake, the largest a magnitude 7.9.
  • About 250 miles (400 km) of Japan's northern Honshu coastline dropped by 2 feet (0.6 meters), according to the U.S. Geological Survey.
  • The jolt moved Japan's main island of Honshu eastward by 8 feet (2.4 m).
  • The Pacific Plate slid westward near the epicenter by 79 feet (24 m).
  • In Antarctica, the seismic waves from the earthquake sped up the Whillans Ice Stream, jolting it by about 1.5 feet (0.5 m).
  • The tsunami broke icebergs off the Sulzberger Ice Shelf in Antarctica.
  • As the tsunami crossed the Pacific Ocean, a 5-foot high (1.5 m) high wave killed more than 110,000 nesting seabirds at the Midway Atoll National Wildlife Refuge.
  • In Norway, water in fjords pointing toward Japan sloshed back and forth as seismic waves from the earthquake raced through.
  • The earthquake produced a low-frequency rumble called infrasound, which traveled into space and was detected by the Goce satellite.
  • Buildings destroyed by the tsunami released thousands of tons of ozone-destroying chemicals and greenhouse gases into the air.

Additional resources

Bibliography

The Chief Scientist of the National Oceanic and Atmospheric Administration is in Seattle.

The Status of Reconstruction and Reconstruction Efforts was published by the Japan Reconstruction Agency.

P.M. Fulton and his team studied the low coseismic Friction on the Tohoku-Oki Fault.

The National Weather Service has a warning system.

Marine debris from Japan. The marine debris program is run by the National Oceanographic and Atmospheric Administration.

Live Science Senior Writer Brandon Specktor updated the article.