{"id":2586,"date":"2013-08-24T05:13:56","date_gmt":"2013-08-23T20:13:56","guid":{"rendered":"http:\/\/rescuejapan.jp\/_wp\/?p=2586"},"modified":"2013-08-24T05:13:56","modified_gmt":"2013-08-23T20:13:56","slug":"japan-earthquake-tsunami-of-2011-facts-and-information","status":"publish","type":"post","link":"https:\/\/rescuejapan.jp\/_wp\/?p=2586","title":{"rendered":"Japan Earthquake & Tsunami of 2011: Facts and Information"},"content":{"rendered":"

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\n \"An<\/span><\/p>\n

\n\tOn March 11, 2011, a magnitude-9 earthquake shook northeastern Japan, unleashing a savage tsunami.<\/p>\n

\n\tThe effects of the great earthquake<\/a> were felt around the world, from Norway’s fjords to Antarctica’s ice sheet. Tsunami debris continues to wash up on North American beaches two years later.<\/p>\n

\n\tJapan still recovering<\/strong><\/h2>\n

\n\tIn Japan, residents are still recovering from the disaster. Radioactive water was recently discovered leaking from the Fukushima Daiichi Nuclear Power Plant<\/a>, which suffered a level 7 nuclear meltdown after the tsunami. Japan relies on nuclear power, and many of the country’s nuclear reactors remain closed because of stricter seismic safety standards since the earthquake. Two years after the quake, about 300,000 people who lost their homes were still living in temporary housing, the Japanese government said.\n<\/p>\n<\/p>\n

\n\tEarthquake a surprise<\/strong><\/h2>\n

\n\tThe unexpected disaster was neither the largest nor deadliest earthquake and tsunami<\/a> to strike this century. That record goes to the 2004 Banda-Aceh earthquake and tsunami in Sumatra, a magnitude-9.1, which killed more than 230,000 people. But Japan’s one-two punch proved especially devastating for the earthquake-savvy country, because few scientists had predicted the country would experience such a large earthquake and tsunami.<\/p>\n

\n\tJapan’s scientists had predicted a smaller earthquake would strike the northern region of Honshu, the country’s main island. Nor did they expect such a large tsunami. But there had been hints of the disaster to come. The areas flooded in 2011 closely matched those of a tsunami that hit Sendai in 869. In the decade before the 2011 Tohoku earthquake, a handful of Japanese geologists had begun to recognize that a large earthquake and tsunami had struck the northern Honshu region in 869. However, their warnings went unheeded<\/a> by officials responsible for the country’s earthquake hazard assessments. Now, tsunami experts from around the world have been asked to assess the history of past tsunamis in Japan, to better predict the country’s future earthquake risk.<\/p>\n

\n\tThe cause<\/strong><\/h2>\n

\n\tThe 2011 Tohoku earthquake<\/a> struck offshore of Japan, along a subduction zone where two of Earth’s tectonic plates collide. In a subduction zone, one plate slides beneath another into the mantle, the hotter layer beneath the crust. The great plates stick and slip, causing earthquakes. East of Japan, the Pacific plate dives beneath the overriding Eurasian plate. The temblor completely released centuries of built up stress<\/a> between the two tectonic plates, a recent study found.<\/p>\n

\n\tThe earthquake started on a Friday at 2:46 p.m. local time (5:46 a.m. UTC). It was centered on the seafloor 45 miles (72 kilometers) east of Tohoku, at a depth of 20 miles (32 km) below the surface. The shaking lasted about six minutes. [Infographic: How Japan’s 2011 Earthquake Happened<\/a>]<\/p>\n

\n\tEarly warning<\/strong><\/h2>\n

\n\tResidents of Tokyo received a minute of warning before the strong shaking hit the city, thanks to Japan’s earthquake early warning system. The country’s stringent seismic building codes and early warning system prevented many deaths from the earthquake, by stopping high-speed trains and factory assembly lines. People in Japan also received texted alerts of the earthquake warning on their cellphones.<\/p>\n

\n\tDeaths<\/strong><\/h2>\n

\n\tMore than 18,000 people were killed in the disaster. Most died by drowning.<\/p>\n

\n\tLess than an hour after the earthquake, the first of many tsunami waves hit Japan’s coastline. The tsunami waves reached run-up heights (how far the wave surges inland above sea level) of up to 128 feet (39 meters) at Miyako city and traveled inland as far as 6 miles (10 km) in Sendai. The tsunami flooded an estimated area of approximately 217 square miles (561\u00a0square kilometers) in Japan.<\/p>\n

\n\tThe waves overtopped and destroyed protective tsunami seawalls at several locations. The massive surge destroyed three-story buildings where people had gathered for safety. Near Oarai, the tsunami generated a huge whirlpool<\/a> offshore, captured on video.<\/p>\n

\n\tNuclear meltdown<\/strong><\/h2>\n

\n\tThe tsunami caused a cooling system failure at the Fukushima Daiichi Nuclear Power Plant<\/a>, which resulted in a level 7 nuclear meltdown and release of radioactive materials. About 300 tons of radioactive water continues to leak<\/a> from the plant every day into the Pacific Ocean, affecting fish and other marine life.<\/p>\n

\"Houses<\/a><\/p>\n

\n\tThe response<\/strong><\/h2>\n

\n\tIn the tsunami’s aftermath, Japan’s Meteorological Agency was criticized for issuing an initial tsunami warning that underestimated the size of the wave. The country recently unveiled a newly installed, upgraded tsunami warning system. In some regions, such as Miyagi and Fukushima, only 58 percent of people headed for higher ground immediately after the earthquake, according to a government study. Many people also underestimated their personal risk<\/a>, or assumed the tsunami would be as small as ones they had previously experienced, the study found.<\/p>\n

\n\tScientists from around the world descended on Japan following the earthquake and tsunami. Researchers sailed offshore and dropped sensors along the fault<\/a> line to measure the forces that caused the earthquake. Teams studied the tsunami deposits to better understand ancient sediment records of the deadly waves. Earthquake engineers examined the damage, looking for ways to build buildings more resistant to quakes and tsunamis. Studies are ongoing today.<\/p>\n

\n\tWorldwide effects<\/strong><\/h2>\n

\n\tThe tsunami waves also traveled across the Pacific, reaching Alaska, Hawaii and Chile. In Chile, some 11,000 miles (17,000 km) distant, the tsunami was 6.6 feet (2 meters) high when they reached the shore.<\/p>\n

\n\tThe surge of water carried tons of debris out to sea as it receded. Japanese docks and ships, and countless household items, have arrived on U.S. and Canadian shores in the ensuing years. The U.S. Coast Guard fired on and sank the derelict boat<\/a> 164-foot Ryou-Un Maru in 2012 in the Gulf of Alaska. The ship started its journey in Hokkaido.\u00a0<\/p>\n

\n\tAmazing facts<\/strong><\/h2>\n

\n\tHere are some of the amazing facts about the Japan earthquake and tsunami.<\/p>\n