Natural Hazards

Japan Tohoku 2011 Earthquake/Tsunami Case Study

Japan Tsunami Devastation 2011

Japan Tsunami Devastation 2011

This is a brief case study with links and information on the Japan Tohoku Earthquake/Tsunami of 11 March 2011


Japan 2011 Earthquake location

Japan 2011 Earthquake location

The earthquake occurred 140km off the coast of Honshu (the largest of the Japanese islands) in Japan.  The focus (sometimes referred to as a hypocentre)  of the earthquake was 32km.

The USGS recorded the information here.

Click here to see an excellent timed interval of the earthquake and the many aftershocks that occurred following the earthquake.

Japan Sendai 2011 Earthquake Location


Japan Earthquake Clock Time

Japan Earthquake Clock Time

Friday 11 March 1446 local time

The earthquake occurred at 2.46pm which resulted in many lives being lost in the initial earthquake due to many office buildings being full as well as busy roads however a large number of lives were saved as it meant that many people were ready to act when the tsunami warning was heard.  Had it been early in the morning many people would have been at home where the chances of their homes collapsing would have been less but then they would probably have responded slowewr to the tsunami warning.  This however is a point of debate.  Please feel free to comment below.

How strong?

The earthquake was originally described as 8.9 on the Richter scale but then later upgraded to 9.0 making it the 4th largest earthquake ever recorded since 1900.  See the article here.


What were the causes?  This is a complex tectonic area.  Japan is located at the boundary between many tectonic plates.

The Sendai earthquake was caused by the Pacific Plate descending beneath Japan at the Japan trench/subduction zone.


  • 15,845 deaths
  • 5,893 injured
  • 3,380 people missing
  • 125,000 buildings damaged or destroyed
  • Heavy damage to roads and railways and other infrastucture
  • Fires
  • Fujinuma Dam collapse
  • 4.4 million households without electricity
  • 1.5 million without water
  • Fukushima Nuclear Power Plant complex shutdown and meltdown – 20km radius evacuated (US Citizens were told to evacuate by at least 80km)
  • Loss estimates £150 billion (US$235)
  • The tsunami broke icebergs off the Sulzberger Ice Shelf in Antarctica, 13,000 kilometres away
  • Along the Pacific Coast of Mexico and South America, tsunami surges were reported, but in most places caused little or no damage.

What Happened Next?

Japan Three Months After the Tsunami

Japan Three Months After the Tsunami

3 months later these pictures from the Boston Globe showed the progress that was being made in the slow clean up.  The before and after pictures are particularly interesting


How Big a Flood


Really like this new BBC website, How Big Really, which gives a sense of scale to the verbatim News Reports we both see and here on the news.  By entering your postcode you can get an idea of how big a natural disaster, environmental disaster, depths, etc,..  Worth checking out the How Many Really too



Hurricane Irene Sunset and weblinks


New York Sunset August 29 2011

This sunset photo following Hurricane Irene in New York City is beautiful.  Taken by Inga Sarda-Sorensen which I found through my Twitter Feed, it underlines the amazing combination of modern communication technology to embrace some truly incredible natural scenes.

Some Hurricane Irene Links:

  • Hurricane Irene has been tracked by Google Maps here 
  • An interesting comparison of Hurricane Irene and Hurricane Katrina here
  • National Hurricane Centre Irene here
  • Hurricane Irene NASA picture here and excellent detailed information here
  • Wikipedia Hurricane Irene here



Christchurch Earthquake Case Study 2011

New Zealand Christchurch Earthquake Location map

New Zealand Christchurch Earthquake Location map

Following the 7.0 on the Richter Scale earthquake of 2010, Christchurch, in New Zealand didn’t expect to receive a second significant earthquake within the space of a year.


At a depth of 5km (focus) of the earthquake occurred  2km west of the town of Lytteltonvery close to Christchurch, the second most populated city  in New Zealand with a population of 390,300. See google map here.

christchurch 2011 earthquake location

Christchurch 2011 earthquake location


Tuesday, February 22, 2011 at 12:51:43 PM at epicentre.


Magnitude 6.3 on the Richter scale. See the USGS info here

The 2010 Christchurch despite being a higher order of magnitude earthquake at 7.1 on the Richter scale happened in the early hours of the morning at 4.35am which explains partly why there were no casualties as the central business district would have been empty with few people in high rise buildings.


The earthquake was part of the aftershock sequence of the M 7.0 September 3, 2010 Darfield, earthquake in New Zealand.

Thrust Fault

Thrust Fault

There is a thrust fault which is linked with the plate boundary between the Pacific and Australian plates which meets in the centre of South Island, New Zealand.

New Zealand plate tectonic map

New Zealand plate tectonic map


  • 181 dead (as of 3 May 2011)
  • 80% of the city had no electricity
  • Water supplies and sewage disposal badly disrupted
  • Road and bridges damaged
  • Liquefaction of the ground (solid ground is shaken so much that water rises quickly up and turns the ground into a liquid state
  • Many historic buildings damaged or destroyed
  • People trapped in rubble (this story really was interesting as I listened to her on the radio talking from her mobile phone whilst trapped under the rubble)

Sink holes and liquefaction on the roads  in Christchurch, New Zealand. 


Short Term

  • In the seconds, hours and days after the earthquake rescue and response was offered by ordinary people as well as the emergency services on duty
  • An emergency meeting Government Cabinet Meeting was held at 3pm. Read more here
  • The Canterbury Art Gallery which had been designed to be earthquake proof survived and was turned into a Emergency Response centre.  Read more here
  • Satellite Imagery was provided for emergency teams to help with allocation of aid and rescue from the US and France. See more here
  • 300 Australian police were flown in brining the number of the police to 1200
  • The police provided security cordons, organised evacuations, supported search and rescue teams, missing persons and family liaison, and organised media briefings and tours of the affected areas.

Medium Term

  • The Red Cross provided grants to families with children under 5 years of age who were living in significantly damaged homes caused by the September or February earthquakes, with their electricity bills. Read more here
  • The police coordinated forensic analysis and evidence gathering of fatalities  working closely with pathologists, forensic dentists and scientists.

Long Term



Iceland Volcano Plumbing

Eyjafjallajokull ash cloud

Eyjafjallajokull ash cloud

A student (thank you Robyn) pointed me in the direction of this excellent article all about the Eyjafjallajokull volcano and its magma plumbing.  It’s a really interesting read particulary how they’re using radimoetric readings from the TerraSAR-X German satellite to look at how the land deformed leading up to the eruption.  This is extremely important in the race to make the science of predicting volcanic eruptions a more accurate one.

Eyjafjallajokull Volcano Plumbing

Eyjafjallajokull Volcano Plumbing

Essentially the eruption was a phreatic one where water mixed with magma to produce the ash materail that caused havoc around Europe for airline travellers. Check out some typically good BBC graphics here on the eruption plume. Check out the brillinat pictures on the eruption on the Boston Globe website here.

Hurricane Igor

Hurricane Igor

Hurricane Igor

My sister in Law lives and teaches in Bermuda.  We’ve been there on holiday and loved its beautiful beaches, white walled houses and fantastic snorkelling (but not its ridiculously high prices!).  Anyway she’s sending me a stream of excellent websites to watch Hurricane Igor, currently rated a Category 1 Hurricane.  Her school is closed for two days to allow the island to recover.  Our thoughts are with them!

  • Stormpulse allows you to track a hurricane as it crosses the Atlantic
  • There is Web Cam here advertised as the Bermuda Sports network

Some Hurricane Tips from the school Leadership are as follows:

There will be loss of power for many people – so:
  • Take cash out of the ATM machine. No power = no ATMs
  • Batteries, flashlights (torches), candles, matches, radio (FM 100.1 – emergency channel – probably the only one working), food supplies, gas for the bbq. CHARGE ALL BATTERIES, CELL PHONE, LAPTOP ETC
  • Don’t go outside during the storm. The biggest risk to you is being hit by flying debris. So spend time when you get home putting everything away – including the thrash can or you will have to buy another one! Get rid of as much trash as possible when the trash collection takes place this week.
  • Try to stay in the safest room. The wind is going to come from the SE, S then SW if the storm passes to our west. (Opposite if it passes to east). So try to be in a room with a good door and few windows. Obviously the basement is preferable if you have one – in case the roof comes off!
  • Just prior to storm – fill all the water containers you have – including the bath. No power = no water pump = no water. So unless you can dip your tank (don’t forget the bucket and rope) – the bath water can be used for flushing. Make sure you know how to access your water tank.
  • Do your laundry before the storm!
  • Try to spend the storm with friends – and you might as well drink the beer as you won’t be able to keep it cold!
  • Fill up your car/bike – no power and the pumps don’t work!
  • Use food from your freezer this week – in case you lose power for a few days and have to throw it away.
  • Take a few photos around your garden and that favourite Poinciana tree in flower.
  • Don’t wait until Saturday to do all this – it will be a mob scene in the stores on Saturday and the forecast is already for gusts up to 60 kts on Sat

5 years since Hurricane Katrina

Hurricane Katrina dogs

Hurricane Katrina dogs

I can’t believe it’s 5 years since Hurricane Katrina.  It was my first year as Head of Geography at Bodmin College and I remember that we’d already had the Boscastle Floods and the Asian Tsunami and later in the year the Kashmir Earthquake.  It was some year for geography case studies.  These brilliant pictures from the Boston Globereally portray the incredible scences during the hurricane event

Flood defence in the UK to cost £1billion


Great article from the Guardian here explaining how half a million houses in the UK will be at considerable flood risk.  The cost of defending them will be far less than the cost of dealing with the floods when they occur.  The cost benefit analysis has to be 5 times the cost of the defences.  Apparently the average cost of a burglary6 in the UK is £1000 whereas the average cost to a home following a flood is £20,000 – £30,000!

How to stop a Meteorite


Boston Globe - Asteroid Impact

A meteor is in the sky , a meteorite has already landed on the the surface, an asteroid is bigger than 1km in diameter.  A shooting star is essentially a a meteor breaking up in the atmosphere.

This interesting website from the ever excellent Boston Globe has a great range of technologies that we humans could employ to divert a potentially catastrophic meteor impact event.

Remember that one theory states that the dinosaurs were probably wiped out by the impact of an asteroid in the Caribbean just of the coast of Mexico.  The Chicxulub crater off the Yucatan peninsula is the supposed location of the impact site.  Recent debate seems to question this theory however as reported here.

The Haiti Earthquake


Some incredible if disturbing images of Haiti from the Boston Globe.  The pictures of residents sleeping in the street and the images of some of the shattered neighbourhoods begin to put a sense of scale on things.  But do we feel increasingly detached looking through the window of the internet at these scenes as we become desensitised to suffering. 

Six days later the situation had improved slightly.  

This article in the Guardian is good at explaining the differences between the neighbouring Dominican Republic and Haiti in particular focusing on the issue of deforestation.  Haiti is 98% deforested!.

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