Friday, March 11, 2011

Earthquake and Tsunami on Japan 2011

2011 Tōhoku earthquake and tsunami


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2011 Tōhoku earthquake and tsunami
An aerial view of tsunami damage in Tōhoku
An aerial view of tsunami damage in the Tōhoku region
2011 Tōhoku earthquake and tsunami is located in Japan
Tokyo
Sendai
Map showing the epicenter of the earthquake
Date 14:46:23, 11 March 2011 (+09:00) (2011-03-11T14:46:23+09:00)
Duration 6 minutes[1]
Magnitude 9.0 Mw[2][3]
Depth 32 km (19.9 mi)
Epicenter location 38°19′19″N 142°22′08″E / 38.322°N 142.369°E / 38.322; 142.369Coordinates: 38°19′19″N 142°22′08″E / 38.322°N 142.369°E / 38.322; 142.369
Type Megathrust earthquake
Countries or regions affected Japan (primary)
Pacific Rim (tsunami)
Total damage Flooding, landslides, fires, building and infrastructure damage, nuclear incidents
Peak ground acceleration 2.99 g
Tsunami Yes
Landslides Yes
Foreshocks 7+ (4+ above 6.0 MW)
Aftershocks 647+ (44+ above 6.0 MW)
Casualties 8,805 deaths,[4][5] 2,628 injured,[4][5] 12,664 people missing[4][5] (all figures preliminary)
v · d · e
The 2011 Tōhoku earthquake and tsunami (東北地方太平洋沖地震 Tōhoku Chihō Taiheiyō-oki Jishin[6]?, literally "Tōhoku region Pacific Ocean offshore earthquake"[fn 1]) was a 9.0-magnitude megathrust earthquake off the coast of Japan that occurred at 14:46 JST (05:46 UTC) on Friday 11 March 2011.[2][3][7] The epicenter was 130 kilometers (81 mi) off the east coast of the Oshika Peninsula of Tōhoku near Sendai, with the hypocenter at a depth of 32 km (19.9 mi).[8][9]
The earthquake triggered extremely destructive tsunami waves of up to 10 meters (33 ft) that struck Japan minutes after the quake, in some cases traveling up to 10 km (6 mi) inland,[10] with smaller waves reaching many other countries after several hours. Tsunami warnings were issued and evacuations ordered along Japan's Pacific coast and at least 20 other countries, including the entire Pacific coast of North America and South America.[11][12][13]
The Japanese National Police Agency has officially confirmed 8,805 deaths,[4][5] 2,628 injured,[4][5] and 12,664 people missing[4][5] across eighteen prefectures, as well as over 125,000 buildings damaged or destroyed.[4][5] The earthquake and tsunami caused extensive and severe structural damage in Japan, including heavy damage to roads and railways as well as fires in many areas, and a dam collapse.[10][14] Around 4.4 million households in northeastern Japan were left without electricity and 1.5 million without water.[15] Many electrical generators were taken down, and at least three nuclear reactors suffered explosions due to hydrogen gas that had built up within their outer containment buildings. On 18 March, the International Atomic Energy Agency described the crisis as "extremely serious."[16] Residents within a 20 km (12 mi) radius of the Fukushima I Nuclear Power Plant and a 10 km (6 mi) radius of the Fukushima II Nuclear Power Plant were evacuated.
Estimates of the Tōhoku earthquake's magnitude make it the most powerful known earthquake to hit Japan, and one of the five most powerful earthquakes in the world overall since modern record-keeping began in 1900.[7][17][18] Japanese Prime Minister Naoto Kan said, "In the 65 years after the end of World War II, this is the toughest and the most difficult crisis for Japan."[19] The earthquake moved Honshu 2.4 m (7.9 ft) east and shifted the Earth on its axis by almost 10 cm (3.9 in).[20][21] Early estimates placed insured losses from the earthquake alone at US$14.5 to $34.6 billion.[22] On March 21, the World Bank estimated damage between $122 billion and $235 billion.[23] The Bank of Japan offered ¥15 trillion (US$183 billion) to the banking system on 14 March in an effort to normalize market conditions.[24]

Earthquake

Map of the Tōhoku earthquake and aftershocks
The 9.0-magnitude (MW) megathrust earthquake occurred on 11 March 2011 at 14:46 JST in the western Pacific Ocean, 130 kilometers (81 mi) east of Sendai, Honshu, Japan, lasting approximately six minutes.[1] Its epicenter was 373 km (232 mi) from Tokyo, according to the United States Geological Survey (USGS) and Japanese Meteorological Agency (JMA). The main earthquake was preceded by a number of large foreshocks, and multiple aftershocks were reported afterwards. The first major foreshock was a 7.2 MW event on 9 March, approximately 40 km (25 mi) from the 11 March quake, with another three on the same day in excess of 6.0 MW.[2][25] Following the quake, a 7.0 MW aftershock was reported at 15:06 JST, followed by a 7.4 at 15:15 JST and a 7.2 at 15:26 JST.[26] Over six hundred aftershocks of magnitude 4.5 or greater have occurred since the initial quake.[27] USGS director Marcia McNutt explained that aftershocks follow Omori's Law, might continue for years, and will taper off in time.[28]
One minute prior to the effects of the earthquake being felt in Tokyo, the Earthquake Early Warning system, which includes more than 1,000 seismometers in Japan, sent out warnings of an impending earthquake to millions. This was possible because the damaging seismic S-waves, traveling at 4 km (2.5 mi) per second, took about 90 seconds to travel the 373 km (232 mi) to Tokyo. The early warning is believed by the JMA to have saved many lives.[29][30]
Initially reported as 7.9 MW by the USGS, the magnitude was quickly upgraded to 8.8 and then to 8.9,[31] and then again to 9.0.[32][3] This earthquake occurred where the Pacific Plate is subducting under the plate beneath northern Honshu; which plate this is is a matter of debate amongst scientists.[33][21] The Pacific plate, which moves at a rate of 8 to 9 cm (3.1 to 3.5 in) a year, dips under Honshu's underlying plate releasing large amounts of energy. This motion pulls the upper plate down until the stress builds up enough to cause a seismic event. The break 130 kilometers (81 mi) off of the coast of Sendai was estimated to be several tens of kilometers long and only 32 km (19.9 mi) deep, and caused the sea floor to spring up several meters, causing the earthquake.[33][34] A quake of this size usually has a rupture length of at least 480 km (300 mi) and requires a long, relatively straight fault line. Because the plate boundary and subduction zone in this region is not very straight, it is unusual for the magnitude of an earthquake to exceed 8.5; the magnitude of this earthquake was a surprise to some seismologists.[35] The hypocentral region of this earthquake extends from offshore Iwate Prefecture to offshore Ibaraki Prefecture.[36] The Japanese Meteorological Agency said that the earthquake may have ruptured the fault zone from Iwate to Ibaraki with a length of 500 km (310 mi) and a width of 200 km (120 mi).[37][38] Analysis showed that this earthquake consisted of a set of three events.[39] The earthquake may have had a mechanism similar to that of another large earthquake in 869 with an estimated surface wave magnitude (Ms) of 8.6, which also created a large tsunami.[40] Other major earthquakes with tsunamis struck the Sanriku Coast region in 1896 and in 1933.
The quake registered at the maximum of 7 on the Japan Meteorological Agency seismic intensity scale in Kurihara, Miyagi Prefecture.[41] Three other prefectures—Fukushima, Ibaraki and Tochigi—recorded an upper 6 on the JMA scale. Seismic stations in Iwate, Gunma, Saitama and Chiba Prefecture measured a lower 6, recording an upper 5 in Tokyo.
Japan's National Research Institute for Earth Science and Disaster Prevention (NIED) recorded a peak ground acceleration of 2.99 g (29.33 m/s²).[42][fn 2]

Energy

This earthquake released a surface energy (Me) of 1.9±0.5×1017 joules,[45] dissipated as shaking and tsunamic energy, which is nearly double that of the 9.1-magnitude 2004 Indian Ocean earthquake and tsunami that killed 230,000 people, and flung the 2,600 ton Apung 1 ship 2 to 3 km (1.2 to 1.9 mi) inland. "If we could only harness the [surface] energy from this earthquake, it would power [a] city the size of Los Angeles for an entire year," McNutt said in an interview.[28] The total energy released, also known as the seismic moment (M0), was more than 200,000 times the surface energy and was calculated by the USGS at 3.9×1022 joules,[46] slightly less than the 2004 Indian Ocean quake. This is equivalent to 9.32 teratons of TNT, or approximately 600 million times the energy of the Hiroshima bomb.

Geophysical impact

The quake moved portions of northeast Japan by as much as 2.4 meters (7.9 ft) closer to North America,[20][21] making portions of Japan's landmass "wider than before," according to geophysicist Ross Stein.[21] Portions of Japan closest to the epicenter experienced the largest shifts.[21] Stein also noted that a 400-kilometer (250 mi) stretch of coastline dropped vertically by 0.6 m (2.0 ft), allowing the tsunami to travel farther and faster onto land.[21] The Pacific plate itself may have moved westwards by up to 20 m (66 ft), though the actual displacement will have diminished with greater distance from the site of the fault.[47] Other estimates put the amount of slippage at as much as 40 m (130 ft), covering an area some 300 to 400 km (190 to 250 mi) long by 100 km (62 mi) wide. If confirmed, this would be one of the largest recorded fault movements to have been associated with an earthquake.[48]
Street and manhole damage after the earthquake
According to Italy's National Institute of Geophysics and Volcanology, the earthquake shifted the Earth's axis by 25 centimeters (9.8 in). This deviation led to a number of small planetary changes, including the length of a day and the tilt of the Earth.[49] The speed of the Earth's rotation increased, shortening the day by 1.8 microseconds due to the redistribution of Earth's mass.[50] The axial shift was caused by the redistribution of mass on the Earth's surface, which changed the planet's moment of inertia. Due to the effects of conservation of angular momentum, such changes of inertia result in small changes to the Earth's rate of rotation.[51] These are expected changes[49] for an earthquake of this magnitude.[20][50]
Shinmoedake, a volcano in Kyushu, erupted two days after the earthquake. The volcano had erupted in January 2011; it is not known if the later eruption was linked to the earthquake.[52] In Antarctica, the seismic waves from the earthquake were reported to have caused the Whillans Ice Stream to slip by about 0.5 m (1.6 ft).[53]

Tsunami

Wave height map of the tsunami from NOAA
Water column height on 11 March 2011 at DART Station, 690 NM Southeast of Tokyo
The earthquake caused a massive tsunami which wrought massive destruction along the Pacific coastline of Japan's northern islands. The tsunami propagated across the Pacific, and warnings were issued and evacuations carried out in many countries bordering the Pacific, including the entire Pacific coast of North and South America from Alaska to Chile;[11][12][13] however, while the tsunami was felt in many of these places, it caused only relatively minor effects. Chile's section of Pacific coast is one of the furthest from Japan, at about 17,000 kilometers (11,000 mi) away,[54] but still was struck by tsunami waves 2 meters (6.6 ft) high.[55][56]

Japan

The tsunami warning issued by the Japan Meteorological Agency was the most serious on its warning scale; it rated as a "major tsunami", being at least 3 m (9.8 ft) high.[57] The actual height predicted varied, the greatest being for Miyagi at 10 m (33 ft) high.[58] The earthquake took place at 14:46 JST around 70 km (43 mi) from the nearest point on Japan's coastline, and initial estimates indicated the tsunami would have taken 10 to 30 minutes to reach the areas first affected, and then areas further north and south based on the geography of the coastline.[59][60] Just over an hour after the earthquake at 15:55 JST, a tsunami was observed flooding Sendai Airport, which is located near the coast of Miyagi Prefecture,[61][62] with waves sweeping away cars and planes and flooding various buildings as they traveled inland.[63][64] The impact of the tsunami in and around Sendai Airport was filmed by an NHK News helicopter, showing a number of vehicles on local roads trying to escape the approaching wave and being engulfed by it.[65] A 4-meter (13 ft)-high tsunami hit Iwate Prefecture.[66] Wakabayashi Ward in Sendai was also particularly hard hit.[67]
Like the 2004 Indian Ocean earthquake and tsunami, the damage by surging water, though much more localized, was far more deadly and destructive than the actual quake. There were reports of "whole towns gone" from tsunami-hit areas in Japan, including 9,500 missing in Minamisanriku;[68] one thousand bodies had been recovered in the town by 14 March 2011.[69]
Tsunami flooding on the Sendai Airport runway
Kuji and Ōfunato have been "swept away ... leaving no trace that a town was there."[70][71] Also destroyed was Rikuzentakata, where the tsunami was reportedly three stories high.[72][73][74] Other cities reportedly destroyed or heavily damaged by the tsunami include Kamaishi, Miyako, Ōtsuchi, and Yamada (all in Iwate Prefecture), Namie, Sōma and Minamisōma (all in Fukushima Prefecture) and Onagawa, Natori, Ishinomaki, and Kesennuma (all in Miyagi Prefecture).[75][76][77][78][79][80] The severest effects of the tsunami were felt along a 670-kilometer (420 mi)-long stretch of coastline from Erimo in the north to Ōarai in the south, with most of the destruction in that area occurring in the hour following the earthquake.[81] Near Ōarai, people captured images of a huge whirlpool that had been generated by the tsunami.[82] The tsunami washed away the sole bridge to Miyatojima, Miyagi, isolating the island's 900 residents.[83]
On 13 March 2011, the Japan Meteorological Agency (JMA) published details of tsunami observations recorded around the coastline of Japan following the earthquake. These observations included tsunami maximum readings of over 3 meters (9.8 ft) at the following locations and times on 11 March 2011, following the earthquake at 14:46 JST:[84]
20110311Houshu.ogg
NOAA animation of the tsunami's propagation
It was also reported the tsunami at Sanrikuchō-ryōri, Ōfunato was at least 23 m (75 ft) high, according to a study conducted by the Port and Airport Research Institute.[85][86]
These readings were obtained from recording stations maintained by the JMA around the coastline of Japan. Many areas were also affected by tsunamis of 1 to 3 meters (3.3 to 9.8 ft) in height, and the JMA bulletin also included the caveat that "At some parts of the coasts, tsunamis may be higher than those observed at the observation sites." The timing of the earliest recorded tsunami maximum readings ranged from 15:12 to 15:21, between 26 and 35 minutes after the earthquake had struck. The bulletin also included initial tsunami observation details, as well as more detailed maps for the coastlines affected by the tsunamis.[87][88]

Elsewhere across the Pacific

Shortly after the earthquake, the Pacific Tsunami Warning Center (PTWC) issued tsunami watches and warnings for locations in the Pacific. At 07:30 UTC, PTWC issued a widespread tsunami warning covering the entire Pacific Ocean.[89][90] The United States West Coast and Alaska Tsunami Warning Center issued a tsunami warning for the coastal areas of most of California, all of Oregon, and the western part of Alaska, and a tsunami advisory covering the Pacific coastlines of most of Alaska, and all of Washington and British Columbia, Canada.[91][92] In California and Oregon, up to 8 ft (2.4 m) high tsunami surges hit some areas, damaging docks and harbors and causing over US$10 million of damage.[93][94] Hawaii estimated damage to public infrastructure alone at $3 million, with damage to private property estimated at tens of millions of dollars.[95] Surges of up to 1 m (3.3 ft) hit Vancouver Island in Canada.[92]
A Bonin Petrel, trapped in the sand on Midway Atoll by the tsunami
Authorities in Wewak, East Sepik, Papua New Guinea evacuated 100 patients from the city's Boram Hospital before it was hit by the waves, causing an estimated US$4 million in damages.[96] Peru reported a wave of 1.5 m (4.9 ft) and more than 300 homes damaged.[97] The surge in Chile was large enough to damage more than 200 houses,[98] with waves of up to 3 m (9.8 ft).[99][100] In the Galapagos Islands, 260 families received assistance following a 3 m (9.8 ft) surge which arrived 20 hours after the earthquake, after the tsunami warning had been lifted.[101][102]
Some other South Pacific countries, including Tonga and New Zealand, and U.S. territories American Samoa and Guam, experienced larger-than-normal waves, but did not report any major damage.[103] Some houses along the coast in Jayapura, Indonesia were destroyed.[104] Along the Pacific Coast of Mexico and South America, tsunami surges were reported, but in most places caused little or no damage.[97] Russia evacuated 11,000 residents from coastal areas of the Kuril Islands.[105] In the Philippines, waves up to 0.5 m (1.6 ft) high hit the eastern seaboard of the country. It was reported that a 5 ft (1.5 m) high wave completely submerged Midway Atoll's reef inlets and Spit Island, killing more than 110,000 nesting seabirds at the Midway Atoll National Wildlife Refuge.[106]

Casualties

Islannin tulivuoret
The bottom MODIS satellite image was taken on 26 February, and the top on 13 March, after the tsunami. Sendai is in the upper third of both (the red circle to its immediate north-east marks a fire). Scale bar is 10 km (6.2 mi).
The National Police Agency has officially confirmed 8,805 deaths,[4][5] 2,628 injured,[4][5] and 12,664 people missing[4][5] across eighteen prefectures.[4][5] These numbers are expected to increase, with casualties estimated to reach tens of thousands.[107]
Prefectural officials and the Kyodo News Agency, quoting local officials, said that 9,500 people from Minamisanriku in Miyagi Prefecture—about a half of the town's population—were unaccounted for.[108] NHK has reported that the death toll in Iwate Prefecture alone may reach 10,000.[63]
Save the Children reports that as many as 100,000 children have been uprooted from their homes, some of whom were separated from their families because the earthquake occurred during the school day.[109]
On 14 March, Kyodo News Agency reported that some 2,000 bodies were found on two shores in Miyagi Prefecture.[110]
It was reported that four passenger trains containing an unknown number of passengers disappeared in a coastal area during the tsunami.[111] One of the trains, on the Senseki Line, was found derailed in the morning; all passengers were rescued by a police helicopter.[112] Der Spiegel later reported that five missing trains in Miyagi Prefecture had been found with all passengers safe, although this information could not be confirmed locally.[113]
By 9:30 UTC on 11 March, Google Person Finder, which was previously used in the Haitian, Chilean, and Christchurch, New Zealand earthquakes, was collecting information about survivors and their locations.[114][115] The Next of Kin Registry (NOKR) is assisting the Japanese government in locating next of kin for those missing or deceased.[116]
One man was killed in Jayapura, Papua, Indonesia after being swept out to sea.[117] Near Crescent City, California, a 25-year-old man who is said to have been attempting to photograph the oncoming tsunami was swept out to sea and confirmed dead.[118]

Damage and effects

Search-and-rescue activities are visible amongst the remains left by the tsunami.
Tsunami damage between Sendai and Sendai Bay.
The degree and extent of damage caused by the earthquake and resulting tsunami were enormous, with most of the damage being caused by the tsunami. Video footage of the worst affected towns shows little more than piles of rubble, with almost no parts of any structures left standing.[119] Estimates of the cost of the damage range well into the tens of billions of US dollars; before-and-after satellite photographs of devastated regions show immense damage to many regions.[120][121] Although Japan has invested the equivalent of billions of dollars on anti-tsunami seawalls which line at least 40 percent of its 34,751-kilometer (21,593 mi) coastline and stand up to 12 meters (39 ft) high, the tsunami simply washed over the top of some seawalls, collapsing some in the process.[122]

Nuclear power plants

The Fukushima I, Fukushima II, Onagawa Nuclear Power Plant and Tōkai nuclear power stations, consisting of a total eleven reactors, were automatically shut down following the earthquake.[123] Higashidōri, also on the northeast coast, was already shut down for a periodic inspection. Cooling is needed to remove decay heat for several days after a plant has been shut down. The cooling process is powered by emergency diesel generators, as in the case of Rokkasho nuclear reprocessing plant.[124] At Fukushima I and II tsunami waves overtopped seawalls and destroyed diesel backup power systems, leading to severe problems including two large explosions at Fukushima I and leakage of radiation. Over 200,000 people have been evacuated.[125] On 16 March, it was reported that favorable winds were carrying radioactive particles from the incidents out to sea, mitigating some of the negative effects.[126] Further into the crisis, helicopters were used to dump water on the Fukushima I plant to further attempt to cool the reactors.[127]
Europe's energy commissioner Guenther Oettinger, in remarks to the European Parliament on 15 March, called the nuclear disaster an "apocalypse", saying that the word was particularly well chosen, and that Tokyo had almost lost control of events at the Fukushima power plant.[128]

Fukushima I and II Nuclear Power Plants

Destruction at the Fukushima site
Japan declared a state of emergency following the failure of the cooling system at the Fukushima I Nuclear Power Plant, resulting in the evacuation of nearby residents.[129][130] Officials from the Japanese Nuclear and Industrial Safety Agency have reported that radiation levels inside the plant are up to 1,000 times normal levels,[131] and that radiation levels outside the plant are up to 8 times normal levels.[132] Later, a state of emergency was also declared at the Fukushima II nuclear power plant about 11 km (7 mi) south.[133] This brings the total number of problematic reactors to six.[134]
On 12 March, a large explosion, thought to be caused by the buildup of hydrogen gas, blew away the roof and outer walls of the Reactor 1 building, releasing a large cloud of dust and vapor, but the reactor itself was not damaged in the explosion.[135][136][137] A BBC journalist reported being stopped 60 kilometers (37 mi) from the blast site by police.[135]
On Sunday, 13 March, Japanese authorities admitted that a partial nuclear meltdown could be occurring in Reactors 1 and 3.[138] On 12 March at 01:17 JST (16:17 GMT), the Japan Atomic Energy Agency announced that it was rating the Fukushima accident at 4 (accident with local consequences) on the 0–7 International Nuclear Event Scale (INES),[139] below the Three Mile Island accident in seriousness.[140] This has been questioned by the French ASN nuclear safety authority. They say the accident can be classed as a 5 or 6, which would be comparable to or worse than the Three Mile Island accident.[141] On 18 March, Japan's nuclear safety agency raised the severity level of the crisis from 4 to 5.[142]
Visualization of before and after damage to Fukushima power plant, Unit 1
Another explosion occurred at Reactor 3 of the Fukushima I plant just after 11:00 JST on 14 March.[143] An exterior wall of the building collapsed, but the reactor vessel was not damaged according to a government spokesperson.[144] At 16:29 UTC on Monday 14 March (14 March 01:29 UTC), the Japanese Nuclear and Industrial Safety Agency announced that the explosion had occurred. The local population was advised by the authorities to stay home until the radioactive situation of the environment is totally clarified.[145] Unlike the other five reactor units, reactor 3 runs on mixed uranium and plutonium oxide, or MOX fuel, making it potentially more dangerous in an incident due to the neutronic effects of plutonium on the reactor and the carcinogenic effects in the event of release to the environment.[146][147][148] Tokyo Electric Power Company (TEPCO) is trying to reduce the pressure within the plants by venting contaminated steam from the reactor vessels into the atmosphere. According to Tomoko Murakami, of the nuclear energy group at Japan's Institute of Energy Economics, this would not result in the release of significant radiation.[149] Residents living within a 20 km (12 mi) radius of the Fukushima I plant were evacuated, as well as residents within 3 km (1.9 mi) of the Fukushima II plant.[150][151][152]
Additionally, it was reported on 14 March at 07:00 EDT that the fuel rods of Reactor 2 at the Fukushima I plant were now fully exposed, and a meltdown of the fuel rods, with the risk of damage to the reactor vessel and a possible radioactive leak, could not be ruled out.[153] As of 14 March 2011 (2011 -03-14), about 160 people have been exposed to dangerous radiation levels near the power stations. One plant employee was killed while operating a crane, eight others have been injured.[154] An additional eleven employees were injured when the Reactor 3 building exploded.[155] Several people received some radiation doses.[156]
USN sailors on humanitarian duty are checked for radiation exposure
On 15 March, at 6:10 am JST an explosion occurred at Reactor 2 of the Fukushima I plant.[157] After the explosion, the radiation level spiked to 8,217 millisieverts (mSv) per hour.[158] The government admitted it was "very probable" that the cores of Reactors 1, 2 and 3 had experienced (partial) meltdowns due to high temperatures.[159] A fourth Fukushima I reactor, Reactor 4, was also rocked by an explosion on 15 March.[160] Radiation levels of up to 400 mSv per hour were recorded near Reactor 4, while 100 mSv per year is considered a safe level.[161]
A US Navy relief group moved from the immediate area after its helicopters detected low-level radiation while returning to their aircraft carrier from a search and rescue mission, 160 km (99 mi) offshore. The flight absorbed the equivalent amount of earthbound background radiation for a month, in the span of about an hour.[162][163]
On 15 March, the radiation level in Tokyo reached 20 times the normal level. The highest level in the Kantō region was 40 times the normal level in Saitama at 11:00 JST but then receded to ten times the normal level. Local officials have assured the public that this is not a threat to human health.[164][165]
A map showing epicenter of earthquake and position of nuclear power plants
On 15 March, at 11:51 JST Japan suspended operations at the stricken Fukushima I nuclear plant after a surge in radiation made it too dangerous for workers to remain at the facility.[166] However, workers returned about an hour later after radiation levels decreased.[161] As of 16 March 2011 (2011 -03-16), five plant workers have died and 22 others have been injured. Two others are reported missing.[167] The government raised the national safety standard governing radiation exposure from 100 to 250 mSv per year, so plant workers could continue their work.[168]
It was reported that radioactive iodine was detected in the tap water in Fukushima, Toshigi, Gunma, Tokyo, Chiba, Saitama, and Niigata, and radioactive cesium in the tap water in Fukushima, Tochigi and Gunma.[169][170][171]

Onagawa Nuclear Power Plant

A fire from the turbine section of the Onagawa Nuclear Power Plant following the earthquake was reported by Kyodo News.[124][172] The blaze was in a building housing the turbine, which is sited separately from the plant's reactor,[129] and was soon extinguished.[173]
On 13 March the lowest-level state of emergency was declared regarding the Onagawa plant by TEPCO, as radioactivity readings temporarily[174] exceeded allowed levels in the area of the plant.[175][176] TEPCO stated this was due to radiation from the Fukushima I nuclear accidents and not from the Onagawa plant itself.[177]

Tōkai Nuclear Power Plant

The number 2 reactor at Tōkai Nuclear Power Plant was shut down automatically.[123] On 14 March it was reported that a cooling system pump for this reactor had stopped working;[178] however, the Japan Atomic Power Company stated that there was a second operational pump sustaining the cooling system, but that two of three diesel generators used to power the cooling system were out of order.[179]

Ports

Fishing boats and building debris washed out to sea
All of Japan's ports were briefly closed after the earthquake, though the ones in Tokyo and southwards soon re-opened. The north-eastern ports of Hachinohe, Sendai, Ishinomaki and Onahama were destroyed, while Chiba port (which serves the hydrocarbon industry) and Japan's ninth-largest container port at Kashima were also affected though less severely. The ports at Hitachinaka, Hitachi, Soma, Shiogama, Kesennuma, Ofunato, Kamashi and Miyako were also damaged and were expected to be out of action for weeks.[180] The Port of Tokyo suffered slight damage; the effects of the quake included visible smoke rising from a building in the port with parts of the port areas being flooded, including soil liquefaction in Tokyo Disneyland's carpark.[181][182]

Dam failure

The Fujinuma irrigation dam in Sukagawa ruptured,[183] causing flooding and washing away homes.[184] Eight people were missing and four bodies were discovered by the morning.[185][186][187] Reportedly, some locals had attempted to repair leaks in the dam before it completely failed.[188] On 12 March, 252 dams were inspected and it was discovered that six embankment dams had shallow cracks on their crests. The reservoir at one concrete gravity dam suffered a small non-serious slope failure. All damaged dams are functioning with no problems. Four dams within the quake area were unreachable. When the roads clear, experts will be dispatched to conduct further investigations.[189]

Water

In the immediate aftermath of the calamity, at least 1.5 million households were reported to have lost access to water supplies.[15][190] By 21 March 2011, this number fell to 1.04 million.[191]

Electricity

According to Tōhoku Electric Power (TEP), around 4.4 million households in northeastern Japan were left without electricity.[192] Several nuclear and conventional power plants went offline after the earthquake. Rolling blackouts began on 14 March due to power shortages caused by the earthquake.[193] The Tokyo Electric Power Company (TEPCO), which normally provides approximately 40 GW of electricity, announced that it can currently provide only about 30 GW. This is because 40 percent of the electricity used in the greater Tokyo area is now supplied by reactors in the Niigata and Fukushima prefectures.[194] The reactors at the Fukushima Dai-ichi and Fukushima Dai-ni plants were automatically taken offline when the first earthquake occurred and have sustained major damage related to the earthquake and subsequent tsunami. Rolling blackouts of three hours are expected to last until the end of April and will affect the Tokyo, Kanagawa, Shizuoka, Yamanashi, Chiba, Ibaraki, Saitama, Tochigi, and Gunma prefectures.[195] Voluntary reduced electricity use by consumers in the Kanto area helped reduce the predicted frequency and duration of the blackouts.[196] By 21 March 2011, the number of households in the north without electricity fell to 242,927.[191]
Tōhoku Electric Power cannot currently provide the Kanto region with additional power, because TEP's power plants were also damaged in the earthquake. Kansai Electric Power Company (Kepco) cannot share electricity, because its system operates at 60 hertz, whereas TEPCO and TEP operate their systems at 50 hertz; this is due to early industrial and infrastructure development in the 1880s that left Japan without a unified national power grid.[197] Two substations, one in Shizuoka Prefecture and one in Nagano Prefecture, can convert between frequencies and transfer electricity from Kansai to Kanto and Tōhoku, but their capacity to do so is limited to 1 GW. With the damage to so many power plants, it could be years before electricity productions levels in eastern Japan return to pre-quake levels.[198]

Oil, gas and coal

Fire at the Cosmo Oil refinery in Ichihara
A 220,000-barrel-per-day[199] oil refinery of Cosmo Oil Company was set on fire by the quake at Ichihara, Chiba Prefecture, to the east of Tokyo,[200] while others halted production due to safety checks and power loss.[201][202] In Sendai, a 145,000-barrel-per-day refinery owned by the largest refiner in Japan, JX Nippon Oil & Energy, was also set ablaze by the quake.[199] Workers were evacuated,[203] but tsunami warnings hindered efforts to extinguish the fire until 14 March, when officials planned to do so.[199]
An analyst estimates that consumption of various types of oil may increase by as much as 300,000 barrels per day (as well as LNG), as back-up power plants burning fossil fuels try to compensate for the loss of 11 GW of Japan's nuclear power capacity.[204][205]
The city-owned plant for importing liquefied natural gas in Sendai was severely damaged, and supplies were halted for at least a month.[206]
Three coal bulk carrier ships in Japanese ports were damaged by the tsunami.[207]

Transport

Japan's transport network suffered severe disruptions. Many sections of Tōhoku Expressway serving northern Japan were damaged.[208] All railway services were suspended in Tokyo, with an estimated 20,000 people stranded at major stations across the city.[209] In the hours after the earthquake, some train services were resumed.[210] Most Tokyo area train lines resumed full service by the next day-12 March.[211] Twenty thousand stranded visitors spent the night of 11–12 March inside Tokyo Disneyland.[212]
Shinkansen bullet train, overhead power lines damaged by earthquake
A tsunami wave flooded Sendai Airport at 15:55 JST,[61] about 1 hour after the initial quake. Narita and Haneda Airport both suspended operations after the quake, with most flights diverted to other airports for about 24 hours.[182] Ten airliners bound for Narita were diverted to nearby Yokota Air Base.[213]
Various train services around Japan were also canceled, with JR East suspending all services for the rest of the day.[214] Four trains on coastal lines were reported as being out of contact with operators; one, a four-car train on the Senseki Line, was found to have derailed, and its occupants were rescued shortly after 8 am the next morning.[215]
There had been no derailments of Shinkansen bullet train services in and out of Tokyo, but their services were also suspended.[182] The Tōkaidō Shinkansen resumed limited service late in the day and was back to its normal schedule by the next day, while the Jōetsu and Nagano Shinkansen resumed services late on 12 March; however, the Tōhoku Shinkansen remained suspended, with visible damage to electrical poles and elevated spans, and the state of the line in harder-hit areas still difficult to ascertain.[216] Services on the Tōhoku Shinkansen partially resumed on 15 March, with one round-trip service per hour between Tokyo and Nasu-Shiobara.[217]
Stranded passengers on a Tokyo train are unloaded using a ladder
Minami-Kesennuma Station on the Kesennuma Line was obliterated save for its platform;[218] anecdotal evidence suggests severe damage to the line as well as other coastal lines (including the Ishinomaki Line and Senseki Line).
The rolling blackouts brought on by the crises at the nuclear power plants in Fukushima had a profound effect on the rail networks around Tokyo starting on 14 March. Major railways began running trains at 10–20 minute intervals, rather than the usual 3–5 minute intervals, operating some lines only at rush hour and completely shutting down others; notably, the Tokaido Main Line, Yokosuka Line, Sobu Main Line and Chūō-Sōbu Line were all stopped for the day.[219] This led to near-paralysis within the capital, with long lines at train stations and many people unable to come to work or get home. Railway operators gradually increased capacity over the next few days, until running at approximately 80% capacity by 17 March and relieving the worst of the passenger congestion.

Telecommunications

Cellular and landline phone service suffered major disruptions in the affected area.[220] Internet services were largely unaffected in areas where basic infrastructure remained, despite the earthquake having damaged portions of several undersea cable systems landing in the affected regions; these systems were able to reroute around affected segments onto redundant links.[221][222] Within Japan, only a few websites were initially unreachable.[223] Several Wi-Fi hotspot providers have reacted to the quake by providing free access to their networks.[223]

Space center

JAXA (Japan Aerospace Exploration Agency) evacuated the Tsukuba Space Center in Tsukuba, Ibaraki. The Tsukuba Space Center has been shut down, with some damage reported. The Tsukuba Space Center houses a control room for part of the International Space Station.[224][225]

Sports

The 2011 World Figure Skating Championships were scheduled to take place from 21–27 March at the Yoyogi National Gymnasium in Tokyo but the International Skating Union decided on 14 March to postpone the event, after the German team announced that it would follow recommendations not to travel to Japan.[226] International Skating Union President Ottavio Cinquanta published a statement on the federation website on 15 March, confirming the cancellation of the event. However, the possibility of re-scheduling remains, said the ISU chief. "The postponement of the event or alternatively the final cancellation is under evaluation."[227]
Also on hold is the ISU Figure Skating World Team Trophy, scheduled for Yokohama on 14–17 April. The ISU is waiting for guidance from Japanese authorities on whether the skating championships can be held. "It is understood that a postponement of the above-mentioned World Championships as well as the holding of the ISU World Team Trophy is subject to the confirmation by the competent Japanese authorities that the situation is back to normal conditions allowing the safe conduct of major ISU sports Events in the Tokyo area," says the ISU.[228]
The 2011 Japanese motorcycle Grand Prix, originally scheduled for 24 April, was moved to 2 October.[229][230]
The 2011 Asia League Ice Hockey finals between the Tōhoku Free Blades and Anyang Halla were to begin on 11 March but the five games were canceled.[citation needed] As of 14 March 2011 (2011 -03-14), no rescheduled dates were announced.
The Japanese national football team canceled their friendly match with Montenegro scheduled for March 25 in Shizuoka. They are currently scheduled to play New Zealand in Tokyo on March 29, however the Japan Football Association is negotiating to have the game moved to Osaka, much further away from the affected area. "We hope to play New Zealand, which like Japan has also suffered damage from a big earthquake," Japan FA president Junji Ogura said in a statement.[231]
The ITF tennis tournament, Japan Future 1, was to take place on Nishitama District, Tokyo from 14-20 March and was cancelled after the qualifying round was completed. The series of four ITF Men’s Circuit Futures tournaments in and around Tokyo, commencing the week of the 14th March 2011 has been cancelled.

Economic impact

An aerial view of the Sendai port, 12 March
Some analysts are predicting that the total recovery costs could reach ¥10 trillion ($122 billion).[232] The northern Tōhoku region, which was most affected, accounts for about 8 percent of the country's gross domestic product, with factories that manufacture products such as cars and beer, as well as energy infrastructure.[233] It includes the northern Miyagi prefecture, where Sendai is located, about 300 km (180 miles) northeast of Tokyo. The Miyagi area includes manufacturing and industrial zones with chemical and electronics plants. It is estimated that Miyagi accounts for 1.7% of Japan's gross domestic product.[234]
The earthquake and tsunami have had significant immediate impacts on businesses such as Toyota, Nissan and Honda, which completely suspended auto production until 14 March. Nippon Steel Corporation also suspended production, Toyo Tire & Rubber Company and Sumitomo Rubber Industries shuttered their tire and rubber production lines, while GS Yuasa closed its automotive battery production. This was expected to hinder supply availability for automakers.[235] Tokyo Electric Power Company, Toshiba, East Japan Railway Company and Shin-Etsu Chemical were suggested as the most vulnerable companies as a result of the earthquake.[236] Sony also suspended production at all its six plants in the area, while Fuji Heavy Industries discontinued production at most of its factories in the Gunma and the Tochigi Prefectures.[237] Other factories suspending operations include Kirin Holdings, GlaxoSmithKline, Nestlé[238] and Toyota amid power cuts.[239] The factory shutdowns, power cuts and the consequent presumed impact on consumer confidence could hurt the national GDP for several months, although economist Michael Boskin predicts "only minimal impact on the Japanese economy overall."[233][240] Following threats of further nuclear leaks, Blackstone Group LP, Continental AG and Bayerische Motoren Werke AG (BMW) were said to be moving their staff outside Japan.[241]
Almost bare instant noodle shelves at a supermarket in Tokyo
Chief economist for Japan at Credit Suisse, Hiromichi Shirakawa, said in a note to clients that the estimated economic loss may be around $171–183 billion just to the region which was hit by the quake and tsunami. On 14 March, the Bank of Japan, in an attempt to maintain market stability,[242][243] injected 15 trillion yen into the money markets to assure financial stability amid a plunge in stocks and surge in credit risk. After it set up an emergency task force to ensure liquidity in the aftermath of the disaster, governor Masaaki Shirakawa and the bank's board also enlarged a programme to buy government bonds to exchange-traded funds to the tune of 10 trillion yen. The BOJ chief told reporters cash injections will continue as needed.[244] However, following the further nuclear leaks, its actions were read by the market as insufficient[245] despite 8 trillion yen being pumped into the market.[246] On 15 March, the Topix index fell again marking a two-day plunge not seen since 1987 as Japan's default risk surged after Prime Minister Naoto Kan warned of further leaks from the damaged nuclear power plant. Commodities were also significantly lower.[247] Residents of Tokyo were also reported to have gone on a panic shopping spree as daily necessities were sought after and gasoline was stocked up with the increasing risk of nuclear radiation leaks.[248]
Chief Cabinet Secretary Yukio Edano has said that Japan's government will convene on 13 March to gauge the economic effects of the catastrophe.[249] He also told NHK Television that about 200 billion yen that was remaining from the budget for the concurrent fiscal year that would end on 31 March would be used to fund the immediate recovery efforts. Additional measures could also hurt Japan's public debt (which is already the highest in the world). This additional spending could hurt demand for government bonds.[233]
Some economic analysts consider that, ultimately, the catastrophe will improve Japan's economy, with increased job availability during restoration efforts. An analyst at JPMorgan Chase, citing the 1989 Loma Prieta earthquake in the San Francisco Bay Area and the Southern California 1994 Northridge earthquake, noted that natural disasters "do eventually boost output." An analyst at Société Générale anticipated that Japan's economy will decline in March but will revive powerfully in subsequent months. After the Kobe earthquake, industrial output dropped 2.6%, but increased by 2.2% the next month, and 1% the following month. Japan's economy then accelerated substantially through the next two years, at more than its former rate.[240] Others are of the opinion that the catastrophe will harm the economy.[250] Some[who?] have argued that those who predict that the reconstruction effort could help Japan's economy have fallen prey to the broken window fallacy.[251]

Global financial impact

An international convenience-store chain benefits from a rush of post-disaster shoppers
In the immediate aftermath of the earthquake, Japan's Nikkei stock market index saw its futures slide 5% in after-market trading.[252] The Bank of Japan said that they would do their utmost to ensure financial market stability.[253] On Tuesday, 15 March, news of rising radiation levels caused the Nikkei to drop over 1,000 points or 10.6% (16% for the week).[254]
Other stock markets around the world were also affected; the German DAX lost 1.2% and fell to 6,978 points within minutes.[255] Hong Kong's Hang Seng index fell by 1.8%, while South Korea's Kospi index slumped by 1.3%.[256] By the end of trading on the day of the earthquake, the MSCI Asia Pacific Index had dropped by 1.8%.[257] Major U.S. stock market indexes rose between 0.5% and 0.7%.[258] Oil prices also dropped as a result of the closure of Japanese refineries, despite the ongoing violence in Libya and expected demonstrations in Saudi Arabia. US crude dropped as low as $99.01 from $100.08 by lunchtime, with Brent Crude falling $2.62 to $112.81.[259] In Hong Kong, Financial Secretary John Tsang warned investors to "take extra care" as the earthquake may have a short term impact on each local stock market.[260]
The share prices of the biggest reinsurance companies Munich Re and Swiss Reinsurance Company fell following the earthquake on speculation that they may face losses "somewhere in the $10 billion range" even after certain costs were absorbed by Japan's primary insurers and the government.[261]
The Japanese yen soared against most of major currencies following the earthquake and reached post-World War II high at 76.25 yen per dollar on speculation Japanese investors would repatriate assets to pay for rebuilding.[262] Since Japan relies heavily on exports the strong yen could damp its economy further. The financial markets instability prompted G7 to hold a conference call on March 17 resulted in agreement on joint forex intervention to sell yen against the dollar.[263] It was the first such a move since 2000.[264]
Peter Bradford, a former member of the United States' Nuclear Regulatory Commission, said that the impact on the nuclear power plant was "obviously a significant setback for the so-called nuclear renaissance. The image of a nuclear power plant blowing up before your eyes on a television screen is a first."[265]

Response in Japan

Government

A convoy of fire engines in the tsunami zone
Prime Minister Naoto Kan announced the government has mobilized the Japanese Self-Defense Forces in various earthquake disaster zones.[266] He asked the Japanese public to act calmly and tune into various media for updated information.[266][267] He also reported numerous nuclear power plants have automatically shut down to prevent damage and radiation leaks.[266] He also set up emergency headquarters in his office to coordinate the government's response.[267]
Evacuation shelters currently are facing a shortage of potable water, food, blankets and bathroom facilities, as the government arranges these necessities to be delivered to where they are needed as soon as possible, from various areas of Japan and abroad.[268] Dropping temperatures due to the disruption in electrical and gas lines caused further problems at shelters.[63] As of 17 March 2011 (2011 -03-17), 336,521 people in Japan had been displaced from their homes and were residing elsewhere, including in 2,367 shelters.[269]
A Japanese urban search and rescue team sent to New Zealand following the 2011 Christchurch earthquake was recalled.[270]

Citizens

"The morality of the Japanese society is amazing. Not one mention or incident of looting or violence. Everyone lines up. Wait your turn to enter the store. Store employees are extremely courteous and kind," wrote a Japanese-American friend of Marianne Kushi of NBC.[271] This attitude has been referred to as the Japanese trait of gaman, loosely meaning "patience and perseverance."[272][273][274]
A human chain helps speed unloading of a rescue flight
A reporter for the Canadian Globe and Mail wrote, "As one catastrophe piled on top of another, a very Japanese deference to authority emerged, as well as a national desire to see civility prevail, no matter the circumstances."[275] The lack of looting and disorder was attributed not only to Japanese forbearance, but to laws that encourage honesty, to a strong police presence, and to three main clans of Yakuza gangs who patrol their territories.[276]
Some people devastated by the quake began, however, to question the government's effort in providing food, clothing, electricity, heat, and phone service. One embittered citizen said, "It's been a week, and there's still been no government help... This is the best they can come up with? What the hell are they doing?" They likened the present condition to that of the 1995 Kobe earthquake, whereupon the government took days to organize relief efforts as opposed to the few hours it took for organized crime groups to distribute blankets and food. The government had promised to hasten relief efforts in the event of a disaster. One citizen said, "The Japanese government should have learned from the Kobe earthquake that they would need help, but they didn't."[277] Chief Cabinet Secretary Yukio Edano later said, "In hindsight, we could have moved a little quicker in assessing the situation and coordinating all that information and provided it faster."[278]
Ten days after the quake, reports began to emerge of incidents of looting and theft in quake and tsunami-hit areas. By 20 March 2011, ¥4.9 million in merchandise from stores and ¥5.8 million in cash was reported stolen to the Miyagi Prefectural Police. Witnesses reported thieves stealing cash and bank books from smashed houses, looting goods from stores, and siphoning gas from abandoned or damaged vehicles.[279][280]

International response

Request for assistance

US Navy transporting JSDF vehicles to the disaster
Japan specifically requested teams from Australia, New Zealand, South Korea, and the United States;[281] it also requested, via its space agency JAXA, the activation of the International Charter on Space and Major Disasters, allowing diverse satellite imagery of affected regions to be readily shared with rescue and aid organizations.[282]

World involvement

Japan received messages of condolence and offers of assistance from a range of international leaders. According to Japan's foreign ministry on 19 March 2011, 128 countries and 33 international organizations had offered assistance to Japan.[191] The EU has also been more than ready to offer its support: "An earthquake powerful enough to make the world wobble on its axis, a massive tsunami, an emergency in nuclear power stations. Any one of these would be a tragedy. Thousands of people have died and this has turned this tragedy into a catastrophe," said Herman van Rompuy, President of the European Council.[283] Twenty Member States have offered assistance through the European Civil Protection Mechanism.[284]
Fire engines have been loaned to Fukushima from US bases in Japan
The Fukushima incident brought the issue of nuclear power to the fore internationally, causing an anti-nuclear demonstration of 50,000 people in Stuttgart and the cancellation of a pro-nuclear press conference in the United Kingdom.[285]
While stepping-up monitoring of radiation levels on its own shores in face of the Fukushima nuclear power plant crisis, China, a major supporter in the relief operations in Japan in spite of its own current earthquake crisis, had officially begun evacuating its citizens from those worst-hit areas in Japan on 15 March 2011.[286] France had also officially begun evacuation of its nationals from the worst-hit areas, dispatching airliners to assist in the evacuation on 16 March 2011.[287][288] Also responding to potential danger of radiation exposure, the government of Austria had relocated its embassy from Tokyo to Osaka some 250 mi (400 km) away.[289]
In many countries, both government and private aid campaigns have been organized to offer money and support to the victims and general populace of Japan. Social buying sites have launched on-line campaigns in which several million dollars were raised for relief organizations working in Japan.[290]
Operation Tomodachi, which means friend in Japanese, was a United States military operation to provide assistance and humanitarian aid to Japan.[291]

Information and support

Russian people take flowers to the embassy of Japan in Moscow
Among several resources offered to help find earthquake survivors and obtain information about people in Japan are: Disaster Message Board Web171 operated by Nippon Telegraph and Telephone,[292][293] the International Committee of the Red Cross,[294] American Red Cross,[295] Google Person Finder,[296] websites of the Australian Embassy,[297] US Department of State,[298] UK Foreign and Commonwealth Office,[299] and the Honshu Quake wiki operated by the CrisisCommons volunteer community.[300]

Media coverage

Japan's national public broadcaster, NHK, and Japan Satellite Television suspended their usual programming to provide ongoing coverage of the situation.[301] Various other nationwide Japanese TV networks also broadcast uninterrupted coverage of the disaster. Ustream Asia broadcast live feeds of NHK, Tokyo Broadcasting System, Fuji TV, TV Asahi, TV Kanagawa, and CNN on the Internet starting on 12 March 2011.[302] YokosoNews, an Internet webcast in Japan, dedicated its broadcast to the latest news gathered from Japanese news stations by translating them in real time to English.[303] The Yomiuri Shimbun reported that the "coordinated relief activities at the disaster sites are expected to deepen the Japan-U.S. alliance."[304]
Non-Japanese media, such as CNN, was noted for being more alarmist, exaggerated, and sometimes inaccurate in its coverage of the earthquake's aftermath than the Japanese media. Fox News Channel at one point displayed "Shibuya Eggman" on a graphic of nuclear plants in Japan. Shibuya Eggman is a concert hall in Tokyo. The alarmist and inaccurate reports in foreign media were speculated to have caused greater anxiety and stress in foreign residents of Japan.[305][306]

Scientific and research response

According to the chief scientist for the Multi-Hazards project at the U.S. Geological Survey, the fact that the Tōhoku earthquake took place in Japan—a country with "the best seismic information in the world"—meant that for the first time, data could be collected that would allow modeling of an earthquake of this type and severity in great detail. Andreas Reitbrock, a professor of seismology at the University of Liverpool, agreed, stating, "It gives us, for the first time, the possibility to model in great detail what happened during the rupture of an earthquake."[20]
Fukushima radiation comparison to other incidents and standards, with graph of recorded radiation levels and specific accident events.(Note: Does not include all radiation readings from Fukushima I site)
The effect of this data is expected to be felt across other disciplines as well. Tom Heaton, a seismological engineer, commented that "the tragedy would provide unprecedented information about how buildings hold up under long periods of shaking – and thus how to build them better. We had very little information about that before now". James Cave, Associate Professor of Earth and Planetary Sciences at Harvard University, said that data retrieved from the earthquake could provide new details in "quake-proofing" large urban areas in the future.[307]
Seismologists had anticipated that the "big one" would strike the same place as the 1923 Kanto earthquake—in the Sagami Trough, southwest of Tokyo.[308][309] Since 1976, when Katsuhiko Ishibashi said a large earthquake in the Suruga Trough was forthcoming, the government tracked plate movements, in preparation for the so-called Tokai earthquake.[310] Occurring 373 km (232 mi) northeast of Tokyo, the Tōhoku earthquake came as a surprise to seismologists, since the Japan Trench was known for creating large quakes, but was not expected to generate quakes above an 8.0 magnitude.[309][310]

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