Nepal Earthquake

Fact File

  • The main earthquake scored a magnitude of 7.8, and hit on April 25th, 2015, between Kathmandu and Pokhara
  • There was a major aftershock on 12th May 2015, of magnitude 7.3
  • It was the worst earthquake to hit in 80 years

Causes

Natural

  • The Himalayas are caused when the northern part of then tectonic plate containing India and Australia pushes up towards the Eurasian plate. Both plates are continental, so relatively light- the crusts both push upwards when they collide, causing huge mountains to form as the Himalayas. Because these rocks started as sedimentary rocks from the sea floor, before the continents collided, seashells can be found in rock faces along the Himalayas
  • Kathmandu is located on soft rock, which, when shaken undergoes “liquefaction”- where solid rock effectively becomes a liquid under stress. This undermined building foundations, causing huge property damage
  • Weak rocks and steep slopes combined to make the aid operations very difficult in the area.

Human

  • Bureaucracy stopped a lot of aid progress, hindering recovery efforts and fostering mistrust between locals and aid organisations
  • Political haggling has effectively stopped aid efforts
  • Corruption among aid workers, particularly Indian aid workers, led to Nepalese blockades in progress, which, according to the Nepalese government, are more damaging than the earthquake itself, economically. Blockades have stopped the flow of construction materials, greatly increasing the costs of rebuilding.
  • Nepal is known as a corrupted country, slowing down aid work and reducing the ability of redevelopment
  • As the earthquake started during the working day, many farm workers were out in their fields, which helped protect them from injuries from falling masonry

Impacts

Short Term

  • Almost 9,000 people were killed, between Nepal, India, Bangladesh and Tibet. Within Tibet, foreign nationals of various countries including Australia, China, India and the USA were killed.
  • People panicked upon seeing the damage and were too scared to return home- this had psychological effects on many individuals, but likely probably helped some people’s safety. As Nepal is hit by frequent tremors, many people are still terrified by small ground movements on a regular basis
  • Dubar Square, a noted UNESCO site was utterly flattened by the shaking
  • 600,000 homes were destroyed
  • 21,000 people were injured
  • The earthquake damaged water supplies from springs down to people causing huge clean water shortages.
  • In the Langtang valley, entire villages were wiped out by avalanches.
  • Many Tibeto-Burman villages were destroyed, as the ethnic group like to settle high up on rocky slopes, making them especially susceptible to land slides and avalanches.
  • Avalanches caused by tremors on mount Everest killed 18 people, making it the day with the highest fatalities on Everest. At least 60 people were injured, and some had to be taken out by rescue helicopters.
  • 4 million people are still living in temporary shelters

Middle Term

  • Many people have taken out large loans to help fund house rebuilding, plunging them into debt.
  • Violent crime rates, particularly against women, greatly increased.
  • Women struggled to get aid, leading to even greater gender disparity within the region
  • People no longer had access to decent sanitation, or to toilets, so there were fears of outbreaks of diseases such as cholera

Responses

Short Term

  • Aid agencies quickly started distributing out survival items like food, bed sheets and crude shelter-making materials (like iron sheets) to help protect people.
  • Airports were reopened as soon as they were safe. That said, some had to be reclosed very quickly afterwards due to aftershocks. During these, people were moved out of the building and onto the runway temporarily, to minimise the risks of injury due to damaged building work.

Middle Term

  • Very few of the roughly 800,000 flattened buildings have been rebuilt.
  • Pledges of US$3×10^9 were made, but 3.5 million Nepalese people have still yet to receive more than very basic aid.
  • The government is starting to give out about 200,000 rupees to the worst effected homes- but only 660 families have received anything so far out of 100,000 eligible, and that is no where near enough to build up new houses or recover losses to the family. Just buying sand for a single room can cost 60,000 rupees.
  • To receive this money, 150,000 of the rupees must be spent on home-building, using a 7 step plan to build earthquake-proof homes. In theory, this would greatly reduce the impac of future earthquakes. In practice, each of the 7 steps is very expensive to locals, who have no means to pay for all of it. If they flout the building rules, they get no compensation.
  • Only about 30% of foreign aid goes to beneficiaries; meanwhile, over 40% is just in admin, breeding discontent between locals who view them as corrupt and the aid companies, slowing down the rebuilding. In Nepal, 43% of the aid money goes to the government. Corruption watchdogs have said that local officials may siphon off even more money

Evaluation of Responses

International aid have been trying to help the area, and on a small scale, they have worked relatively well. Where they can work without funding, such as by building small evacuation camp latrines out of bamboo and rock, they are very effective. However, corruption, and growing irritation at the corrupted system has lead to complications and delays to the extent where very little has really been achieved by aid workers, despite their best efforts.

Many locals would probably be fine helping themselves to build housing, as many people are using loaned money to build their homes faster than they could on the government money, if the supply were supported, instead of being crippled by protest groups.

It’s understandable why they are protesting- at a time when their country needs all the help it can sensibly receive, the government has been redirecting funding away- but their protests merely exacerbate the issues they are complaining about, at least from an outside perspective. It’s unlikely they will change anything with corruption soon.

References

http://www.bbc.co.uk/news/world-asia-36089960

https://www.theguardian.com/global-development/2016/apr/25/earthquake-survivors-stranded-nepal-aid-bureaucracy

https://www.theguardian.com/careers/2016/jul/18/nepal-earthquake-emergency-sanitation-red-cross

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Tohoku Earthquake

Fact File

  • Caused by a magnitude 9 earthquake
  • The wave reached South America within 21 hours; when it hit Chile, 17,000 km away, it was still 2 metres tall
  • The Earthquake started at 2:46PM on March 11th 2011, 24km below the surface and about 70km offshore
  • The shaking lasted around 6 minutes
  • The wave was up to 39 metres high and went up to 10 km inland
  • Around 561 km^2 were flooded
  • The first tsunami wave hit about an hour after the initial earthquake
  • The earthquake was large enough to just shorten the day (by a few microseconds) and slightly change Earth’s axis of rotation.
  • There were 5,000 aftershocks

Causes

Natural

  • The 2011 Tohoku earthquake struck offshore in a subduction zone in the crust, where the Pacific Plate descends beneath the Eurasian Plate
  • There was a clay layer lining the plate boundary, lubricating the fault. This allowed the crust to move a huge distance of around 50m in one go
  • According to the US geological Survey, around 400km of coastline dropped by 2 m from the quake, worsening the wave’s effects. Furthermore, this will have impacts on any subsequent tsunamis in the region’s impacts

Human

  • Japan is a very populated country, particularly along the East coast, where the wave approached from
  • Only 58% of people started heading to higher ground once they had a tsunami warning. The others assumed the tsunami would be small.
  • Around 100 tsunami evacuation sites were hit by the wave- they had not been built high up enough

Impacts

Short Term

  • Fukushima Daiichi Nuclear Power Plant suffered a level 7 nuclear meltdown, due to a cooling system failure caused by the water
  • The government estimated that US$300 x10^9 of damage was caused
  • The surge destroyed 3-storey buildings where people had gone to for shelter
  • 45,700 buildings and 230,000 vehicles were destroyed
  • Entire towns were wiped out
  • 15,891 people were confirmed to have died either immediately or from the flooding by April 10th 2015- most by drowning
  • In 3 days, and just one town, 1,000 bodies had already been found.
  • 1.5 million homes had no access to clean water supplies
  • 110,000 nesting birds were killed on island wildlife reserves throughout the pacific; a relatively minor impact compared to the impacts on Japan.

Middle Term

  • Access to power plants had to be stopped after the tsunami, due to fears that more of the nuclear power plants that Japan relies on for power would be leaking radioactive material. Some still remain closed.
  • Due to the shut down of their nuclear power plants, Japan had to use fossil fuels from outside the country, which cost vast amounts of money that could have gone to helping evacuees
  • Rolling blackouts occured due to loss of power generation, which only worsened the power situation, leading to a cyclical worsening situation until it was resolved
  • Public transport was largely unusable for a while
  • Tsunami seawalls were destroyed at several locations

Long Term

  • Areas near the powerplant got so irradiated that it will be uninhabitable to humans for up to thousands of years in the surroundings
  • In July 2013, TEPCO (Tokyo Electric Power COmpany) stated that around 300 tonnes of radioactive waste still leaks from the plant daily- 800,000 tonnes of contaminated water are stored in 1,000 tanks around the Fukushima site.
  • Radioactive material can be found washed up all along the Northern Pacific shoreline, especially the USA
  • Debris was still washing up on the USA’s shore two years later
  • Damaged buildings released many tones of greenhouse gases, which will impact climate change in the future
  • 230,000 people still are not in permanent housing; 180,000 evacuees (100,000 of which came from near Fukushima)
  • There are still around 2,500 missing people

Responses

Short Term

  • Japan has an early warning system which detects movements of the crust near to the fault line, and sends out an electric signal. The signal travels faster than the shockwave, which gave people about a minute’s warning of the shaking- the signal triggers alerts on phones and some TV sets.
  • The early warnign system also shuts off systems like nuclear power plants and trains, to help minimise the dangers of sudden shaking.
  • More than 160,000 people were evacuated from the coastlines after the tsunami had hit; 470,000 were evacuated from around Fukushima once it was clear there was a major issue with the system
  • Many countries sent search-and rescue teams; Japan deployed their self-defence forces, and worldwide charities supported the area. The Japanese Red Cross received US$1×10^9 in donations.

Middle Term

  • Researchers flooded in to measure activity and changes to the area around the moved faultline
  • Engineers also studied the collapsed buildings to learn more about how to earthquake and tsunami-proof buildings effectively.

Long Term

  • The government had made predictions of a smaller earthquake to occur around the same time, but they massively underestimated. However, they are still working to try to predict earthquakes to prepare in advance for them
  • Some geologists had found evidence that there was a tsunami of similar proportions in 893, and tried to warn the government of its scale, but they largely ignored the warnings they had about how large a tsunami might become

Evaluation of Responses

Japan had attempted to have a very varied range of responses to minimise the effects of tsunamis, and for the most part, they would have been effective. However, they were crippled by massive under estimates of the magnitude of the tsunami and the earthquake, and so provisions were made only for a far less serious disaster.

There was some degree of almost “casualisation” of earthquakes, leading to people not taking all available measures to keep themselves safe (most obviously staying on low land). Japan is generally very well equipped for earthquakes, which certainly greatly reduced the impact to the country as a whole.

 

References

http://www.livescience.com/39110-japan-2011-earthquake-tsunami-facts.html

http://www.ibtimes.co.uk/2011-japan-earthquake-tsunami-facts-about-devastating-event-that-killed-15800-1547423

http://www.bbc.co.uk/news/world-asia-35781593

Eyjafjallajokull

Fact File

  • The drifting ash cloud was travelling at 20,000ft to 35,000ft (6-10km) high
  • Most eruptions are around 6km high
  • 140 million m^3 of ash released in the first 72 hours
  • The eruption which caused the most disturbance started on the 14th of April 2010
  • The first eruption was on the 20th of March 2010.
  • The April eruption began in a 2.5km wide caldera
  • About 750 tonnes of rock were ejected every second
  • Ash stopped emerging in June 2010
  • A large magma chamber just below the surface resulted in quick deformation of the mountain
  • The volcano had been dormant for about 2 centuries beforehand

Causes

Natural

  • The volcano was based under a glacier, so the ice melted and came into contact with magma, which resulted in very fine ash being released into the atmosphere
  • Airlines were distrubed more by frequent stretches of winds from the North and North-West
  • The first eruption started on an iceless section of the slope, which caused lava but not much ash
  • There was about 1 km^3 of ice in the caldera, 25% of which melted in the initial eruption
  • There were at least 2 magma chambers, leading to the 3 separate eruptions

Human

  • Icelandic people are generally very prepared for volcanoes, living in an extremely geologically active area
  • There were recently drills for what to do in the case that the nearby volcano, Katla, erupted before the eruption so that they knew what to do in the event of an eruption in the area.

Impacts

Short Term

  • Melting ice caused flooding in Southern Iceland
  • Depostis of ash across Iceland and other parts of Europe in varying thicknesses

Middle Term

  • Major Disruption to European airlines (fine ash can cause damage to the plane engines)- the UK airspace was closed for the 15th to 20th of April
  • Another eruption on 9th May caused disturbance to Spanish flights
  • Disruptions to flights caused 1,000s to have to travel overland instead of by plane back to their homes

Long Term

  • The volcano drew visibility to Iceland, particularly the South, which helped increase tourism to the area, which helped to allow airlines to grow back their losses from earlier once the ash had settled down

Responses

Short Term

  • Roads in Southern Iceland are mostly built on embankments with small gaps in-between (on bridges)  for rivers to flow between. Before the flood reached the sea, short holes and channels were cut into the plains in the south of the country, to reroute water from the bridges. Repairing holes in the embankment is a lot cheaper than repairing the bridges.

Middle Term

  • A series of guidlines about ash densities which aeroplanes can tolerate allowed airlines to resume business fairly quickly

Long Term

  • The Icelandic government gives volcano drills so citizens know exactly what they’re meant to do in response.
  • A conference of scientists went to the volcano during 15-16 September 2010 to investigate the eruption and research it
  • The volcano had been studied for almost 2 decades to look at how volcanoes in cold environments erupt- data from this and the subsequent conference should help to predict volcanic eruptions and minimise disruption later.

Evaluation of Responses

Impacts were ultimately low, and only lasted a few months. Icelandic awareness of volcanoes and how to respond to them helped to minimise any impacts on property and the causation of casualties.

Most of the Icelandic response is preemptive, and more to help with volcanoes in general, than any specific volcano. This mindset helps individual people to avoid any negative impacts on themselves as quickly as possible. It also helps to minimise costs on the emergency services, as they don’t need to interfere so much with trained individuals’ rescues.

References

http://news.bbc.co.uk/1/hi/world/europe/8634944.stm

http://www.bgs.ac.uk/research/volcanoes/icelandic_ash.html

http://volcano.si.edu/volcano.cfm?vn=372020

http://www.livescience.com/8993-iceland-eyjafjallajokull-volcano-erupted.html