Short & Long Term Impacts of Great Tohoku Earthquake
The Great Tohoku Earthquake had profound short and long-term effects on Japan and its people. The transport network faced significant disruption with damaged expressways, derailed trains, and a damaged airport.
LAND SUBSIDENCE - Some coastal areas in Japan experienced land subsidence as the earthquake dropped the beachfronts in some places by more than 50cm, making the areas more susceptible to flooding
TSUNAMI - The earthquake triggered a tsunami (which hit about 30 minutes following the quake) up to 40m high in Japan. It devastated entire towns & resulted in the loss of 1000's of lives. However, waves also travelled to the east. Tsunami warnings were issued right across Pacific Ocean & were felt in Alaska & Chile (over 11,000 miles away, but measured 2m tsunami waves). Flooding caused huge amounts of damage. Pollution carried in the water settled far inland & sources of clean drinking water were affected in some cases for up to a year
FORE & AFTERSHOCKS - The quake was preceded by a number of foreshocks (one measuring 7.2 on 9 March) & 100's of aftershocks. 3 aftershocks measuring more than magnitude 6 took place on the same day & another 3 measuring more than mag. 7. Some scientists estimate that over 800 quakes of mag. 4.5 or more have been recorded since the main quake. Each quake was caused by plate movement, which created further tears & fissures in the ground, & damage across Japan
Long Term Impacts On
The Environment!
ANTARCTICA - In Antarctica the seismic waves from the earthquake were reported to have caused some massive slabs of ice (one about the size of Manhattan Island) to fall from the Sulzberger Ice Shelf
AFTERSHOCKS - Japan has experienced over 900 aftershocks since the quake, some of which were over magnitude 7, killed people, caused damage to electricity supplies and damage to the Higashidori nuclear power plant
LIQUEFACTION - Liquefaction occurred in many of the parts of Tokyo built on reclaimed land. Around 30 homes were destroyed and 1,046 buildings were damaged by this process alone
EARTH AXIS SHIFT - The earthquake shifted the Earth's axis by between 10-25cm, shortening the day by 1.8 microseconds
SEABED MOVEMENT - The seabed near the epicentre shifted by 24m & the seabed off the coast of the Miyagi province has moved by 3m
PLATE MOVEMENT - Some people estimate that the Pacific plate has slipped westwards by between 20-40m
COASTLINE MOVEMENT - A 250 mile stretch of coastline dropped by 0.6m, allowing the tsunami to travel further inland
LANDMASS MOVEMENT - The quake moved parts of north-east Japan 2.4m closer to North America, making parts of the Japanese island landmass wider than before
Short Term Impacts
On People!
POWER SUPPLIES - Around 4.4 million households in north-east Japan were left without electricity. Power blackouts were experienced for around 3 months in many areas
DAMAGES - 332,395 buildings, 2,126 roads, 56 bridges & 26 railways were destroyed/damaged by earthquake or following tsunami. 300 hospitals were damaged & 11 were totally destroyed. An estimated 23,000 cars & trucks were damaged/destroyed. Ports were closed for nearly 3 weeks. 1 dam ruptured & another 6 had cracks
DEFENCES INEFFECTIVE - Japan had spent billions of dollars building anti-tsunami defences at heights of 12m. However the tsunami just washed over them, making them totally ineffective. The flood waters (in some cases) moved 6 miles inland, destroying houses, factories, roads & other buildings
NUCLEAR CRISIS - Although the Fukishima nuclear plant was protected with a 5m high tsunami barrier, a 9m high wave crashed ashore & flooded plant's generators & electrical wiring. People lost energy immediately & this took some time to restore
DEATH & INJURY - An estimated 20,352 people died, 5,314
people were injured & 130,927 were displaced
Long Term Impacts
On People!
REBUILDING - A panel called the 'Japan Move Forward Committee' proposed that young adults & teenagers could help rebuild parts of Japan devastated by the earthquake
TRANSPORT - Japan's transport network suffered huge disruptions. Sections of the Tohoku Expressway were damaged, Sendai airport was hit by the tsunami wave, 4 trains were derailed & over 1,100 sections of rail line needed to be repaired
NUCLEAR ENERGY - The damage caused by the earthquake
resulted in the meltdown of 7 reactors, which led to the
evacuation of the local area & a 12 mile exclusion zone was set up (200,000 residents). Radiation levels at one point were over 8 times normal levels. Radioactive water & leaks contaminated local areas, with radioactive soil & hotspots being found as far south as Tokyo. Food products were also contaminated, including some fish & beef. The amount of damage to nuclear safety raised safety concerns both in Japan & around the world regarding nuclear energy. Protests about the use of nuclear power in Japan were organised in Tokyo on 27 March 2011 & all Japanese nuclear reactors were taken offline until June 2012
FURTHER CASUALTIES - 3 members of the Japan ground self-defence force died whilst conducting relief operations. The Japanese government estimate that a further 922 people have died as a result of the harsh living conditions since the earthquake
TSUNAMI - A Japanese government study found that only 58% of people in the coastal areas that were affected by the tsunami heeded the tsunami warnings immediately after the earthquake & headed for higher ground. Only 5% of those who attempted to evacuate were caught in the tsunami, whereas the water hit 49% of those who didn't heed the warning
ECONOMY - World Bank estimates that the economic cost of this event was US$235 billion, making this the most expensive natural disaster in world history! They reckon it will take Japan 5 years to rebuild