Saturday, 6 April 2013

Why evacuate for an earthquake no-one can feel?



Quake-striken bar in L'AquilaThe region still bears the scars of the 2009 earthquake
It's four years since the deadly earthquake in L'Aquila, Italy, and six months since scientists were convicted of manslaughter for failing to communicate the danger. Today, evacuation orders are issued much more readily - too readily, some say.
"Everyone knows, you can't predict an earthquake."
Anne Thornley-Bennett, who lives in the Italian town of Barga, categorically believes this. So why, on 31 January, did she decide to evacuate when the local council sent out warnings of a major quake?
"We received dozens of phone calls and text messages, one of which just said, 'Evacuate'. We just went along with the mania," she sighs.
"If it had only been my husband and me, I don't think we'd have taken the advice. We'd have just stayed on the bottom floor in our sleeping bags as we'd done the previous nights. But when you've got little ones... well, if anything did happen, you'd never forgive yourself."
Barga is situated in the picturesque but seismically shaky Garfagnana region of Tuscany. For a week they had been experiencing constant tremors and aftershocks.

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"It was pretty scary because you could hear the earth groan. One day the kids were even evacuated from school without their coats." She laughs, implying that only a real emergency would see Italian children being sent outside coatless in winter.
Garfagnana experienced a huge 6.5 magnitude quake in 1920, yet the local authorities and population have never panicked like this before.
One mayor's decision to evacuate a town centre on 31 January spread fear to the surrounding municipalities, where thousands of residents ended up being advised to sleep in their cars or in schools transformed into emergency shelters. Hospitals and care homes were emptied. In the end, nothing happened. The following day, everyone went home.
Italy never used to worry quite so much about little tremors.
The change appears to be the direct result of last year's conviction of seven members of Italy's High Risk Commission - six of whom were scientists - for manslaughter. They were found guilty of failing to properly communicate the risk of a major earthquake in L'Aquila.
The case has produced its own kind of aftershock.

Garfagnana alarm timeline

  • 21:00 - Mayor of Castelnuovo di Garfagnana gets warning from Civil Protection Dept. of possible strong tremors after a week of smaller tremors
  • 22:19 - The mayor tweets a message advising residents to "sleep away from home", then decides to evacuate the historic town centre
  • 22:39 - Mayor of Barga advises citizens of possible tremors and invites people living in tall or at-risk buildings to leave home
  • 07:30 - Confirmation that geophysicists registered no overnight tremors, followed later by statement from Civil Protection authorities emphasising that evacuation decision was taken by mayors
"Alarmism? It's the poisoned fruit of the L'Aquila sentence," says Franco Gabrielli, the head of the Civil Protection Department, the day after the Garfagnana evacuations.
His spokesperson Francesca Maffini says it's inevitable that scientists are now erring on the side of caution.
"It's not the verdict itself, it's the very fact they were put on trial," she says. "If the risk is between zero and 40%, today they'll tell us it's 40, even if they think it's closer to zero. They're protecting themselves, which is perfectly understandable."
Prof Stefano Gresta, president of the National Institute of Geophysics and Vulcanology (INGV), acknowledges the convictions had a big impact.
"We are more aware that our role as scientists must be exclusively limited to our results and interpretations," he says.
Quake-striken village near L'AquilaThe quake in 2009 killed more than 300 people
But he also thinks something went wrong on 31 January in Barga with the way the scientific tremor prognosis was communicated between the various levels of decision-makers. The escalation of events that night stemmed from a single tweet sent by a council, advising residents to "sleep away from home".

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In the past, information was interpreted and filtered by the likes of the High Risk Commission, the Civil Protection Department and local and regional councils. Today you can get it directly from source through smartphone apps with names like Terremoti Italia (Italy Earthquakes) and Hai sentito il terremoto? (Translation: did you feel the earthquake?)
Keane, an Irish expat artist and journalist (with only one name) who has lived in Barga for 28 years, thinks this is making people obsessive.
"Some apps tell you every time there's a tremor, including the small ones that humans can't even feel. Mine says there were 15 today in Italy, two in this area. You get constant beeps in your pocket and in the end it becomes a psychosis," he says.

Previously in the Magazine

In October 2012, six scientists and one government official were imprisoned for manslaughter, for making "falsely reassuring" comments before the 2009 L'Aquila earthquake. But was this fair?
First, we have to understand limits of earthquake science.
It is possible to predict where an earthquake might happen at some point. But it is impossible accurately to predict exactly when that earthquake will happen.
Ninety-nine times out of a 100, a series of tremors will not result in a larger earthquake. In L'Aquila, it did.
It's a phenomenon that worries Gresta. He does not consider alarmism and sleeping in cars to be the solution, and would prefer to see changes in construction.
"There needs to be greater awareness of the vulnerability of the houses we live in and the buildings we work in and, where appropriate, they should be made safer," he says.
But this will cost councils and homeowners money.
And Thornley-Bennett says people in Barga who chose to evacuate did not really mind.
"We met lots of people we knew and the kids played with their friends. At about 2am, council staff turned up with hundreds of white plastic chairs so we could all sit around and chat. In the morning, we took the children off for breakfast in their pyjamas and then we went home."
Although frightened by the tremors themselves, on that particular night her children had the time of their lives.

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