Why the Haiti earthquake may not have been a natural disaster

 

A A A

Deforestation and extreme weather may later cause earthquakes, scientists believe.

Their findings suggest that cutting down trees on steep slopes may increase the risk of not only landslides but earthquakes in heavily deforested places such as Haiti, which suffered a devastating magnitude 7 quake in 2010.

Geologists have previously discounted the idea that low atmospheric pressure associated with tropical cyclones can influence the timing of earthquakes. But the new study suggests a different mechanism based on changes to the weight of soil and other ground material bearing down on a geological fault under seismic stress.

"Very wet rain events are the trigger. The heavy rain induces thousands of landslides and severe erosion, which removes ground material from the Earth's surface, releasing the stress and encouraging movement along faults," said Shimon Wdowinski of the University of Miami in Florida.

"The 2010 earthquake in Haiti occurred... 18 months after the same area was hit by two tropical storms and two hurricanes," he said. "It can happen in other mountainous areas affected by cyclones, such as Japan, the Philippines, and maybe Central America," he told the American Geophysical Union in San Francisco.

The idea the weather can play a role in triggering earthquakes is controversial. But Dr Wdowinski said an analysis of the timing of earthquakes and cyclones in Taiwan over the past 60 years has demonstrated a statistical correlation, with a significant number of quakes bigger than 6 occurring within four years of major cyclones – known as typhoons in the Far East.

Taiwan was hit in 1969 by Typhoon Flossie, then a 6.2 quake hit Taiwan in 1972. In 2009, Typhoon Morakot was followed by a 6.2 quake in the same year, and a 6.4 quake in 2010. Typhoon Herb, in 1996, was followed by a 6.2 quake in 1998 and a 7.6 quake in 1999.

Dr Wdowinski said rapid soil erosion on steep slopes caused by tropical cyclones changed the stress on the geological fault over a period of months or years, which can trigger an earthquake.

"Statistical analysis showed that the timing of the earthquake is above the expected. It is way above background. If it was a random process and there was no relation between earthquakes and cyclones... there was less than 1 per cent probability of this occurring," he said.

"It is not that it happens during a cyclone but that there is a delay, and the delay of between three months and three years is due to the ground erosion. The delays can be due to the time it takes for the erosion to wash the material to the ocean," he said.

An independent analysis of ground movements caused by summer monsoons in the Himalayas also suggested a link between extreme weather and earthquakes.

A study by Thomas Ader of the California Institute of Technology in Pasadena found that earthquakes were more likely to occur in dry winter months after the monsoon period.

VIDEO
Have you tried new the Independent Digital Edition iPad app?
News
Strange 'quack' noises could be undersea chatter of Minke whales
science
Voices
voices Furore is yet another example of shameful Westminster evasion, says Nigel Farage
News
weird news... and film it, obviously
News
peopleThis time as he’s awarded the Freedom of Stirling and handed an honorary degree
Arts & Entertainment
tv
Sport
sport
News
Matthew Mcnulty and Jessica Brown Findlay in 'Jamaica Inn'
mediaHundreds complain over dialogue levels in period drama
Voices
voicesMoyes' tragedy is one the Deputy PM understands all too well, says Matthew Norman
News
peopleJay Z and Beyoncé to buy £5.5m London townhouse
Voices
voicesMoyes' tragedy is one the Deputy PM understands all too well, says Matthew Norman
Arts & Entertainment
Rocker of ages: Chuck Berry
musicWhy do musicians play into old age?
News
Jilly's jewels: gardener Alan Titchmarsh
peopleCountry Life magazine's list of 'gallant' public figures throws light on what it means to be a gentleman in the modern world
Sport
John Terry goes down injured in the 70th minute
sportAtletico Madrid 0 Chelsea 0: Blues can finish the job at Stamford Bridge, but injuries to Terry and Cech are a concern for Mourinho
Have you tried new the Independent Digital Edition iPad app?
iJobs Job Widget
iJobs General

Cover Supervisor Needed Nottingham/Derbyshire

£3360 - £16800 per annum: Randstad Education Nottingham: Cover Supervisor requ...

English Teacher

£6720 - £33600 per annum: Randstad Education Nottingham: Urgently Required. En...

Supply teachers needed in Cambridgeshire

£21000 - £35000 per annum: Randstad Education Cambridge: Randstad are looking ...

Geography Teacher

£6720 - £33600 per annum: Randstad Education Nottingham: We are currently recr...

Day In a Page

Brits who migrate to Costa del Sol more unhappy than those who stay at home

It's not always fun in the sun: Moving abroad does not guarantee happiness

Brits who migrate to Costa del Sol more unhappy than those who stay at home
Migrants in Britain a decade on: They came, they worked, they stayed in Lincolnshire

Migrants in Britain a decade on

They came, they worked, they stayed in Lincolnshire
Chris Addison on swapping politics for pillow talk

Chris Addison on swapping politics for pillow talk

The 'Thick of It' favourite thinks the romcom is an 'awful genre'. So why is he happy with a starring role in Sky Living's new Lake District-set series 'Trying Again'?
Why musicians play into their old age

Why musicians play into their old age

Nick Hasted looks at how they are driven by a burning desire to keep on entertaining fans despite risking ridicule
How can you tell a gentleman?

How can you tell a gentleman?

A list of public figures with gallant attributes by Country Life magazine throws a fascinating light on what it means to be a gentleman in the modern world
Pet a porter: posh pet pampering

Pet a porter: posh pet pampering

The duo behind Asos and Achica have launched a new venture offering haute couture to help make furry companions fashionable
A History of the First World War in 100 moments: The mutiny that sent a ripple of fear through the Empire

A History of the First World War in 100 moments

The mutiny that sent a ripple of fear through the Empire
Hot stuff: 10 best kettles

Hot stuff: 10 best kettles

Celebrate St George’s Day with a nice cup of tea. Now you just need to get the water boiled
Sam Wallace: Why Giggs is perfect fit as Manchester United boss... in the longer term

Sam Wallace

Why Ryan Giggs is perfect fit as Manchester United boss... in the longer term
Renaud Lavillenie: The sky's the limit for this pole vaulter's ambitions

Renaud Lavillenie: The sky's the limit for this pole vaulter's ambitions

Having smashed Sergei Bubka's 21-year-old record, the French phenomenon tells Simon Turnbull he can go higher
Through the screen: British Pathé opens its archives

Through the screen

British Pathé opens its archives
The man behind the papier mâché mask

Frank Sidebottom

The man behind the papier mâché mask
Chris Marker: Mystic film-maker with a Midas touch

Mystic film-maker with a Midas touch

Chris Marker retrospective is a revelation
Boston runs again: Thousands take to the streets for marathon as city honours dead and injured of last year's bombing

Boston runs again

Thousands of runners take to the streets as city honours dead of last year
40 years of fostering and still holding the babies (and with no plans to retire)

40 years of fostering and holding the babies

In their seventies and still working as specialist foster parents