L’Aquila, Guiliani and the price of earthquake prediction

Image Credit: Andy Paiko Glass

“The first tremors in the region were felt in mid-January and continued at regular intervals, creating mounting alarm in the medieval city, about 100 km (60 miles) east of Rome. Vans with loudspeakers drove around the town a month ago telling locals to evacuate their houses after [Giampaolo] Giuliani, from the National Institute of Astrophysics, predicted a large quake was on the way, prompting the mayor’s anger. Giuliani, who based his forecast on concentrations of radon gas around seismically active areas, was reported to police for “spreading alarm” and was forced to remove his findings from the Internet”. — Gavin Jones, Reuters, 6 April 2009.

On 6 April, 2009, at 03:32 local time (01:32 GMT) an earthquake of magnitude 5.8 on the Richter scale struck central Italy with its epicentre near L’Aquila. The earthquake killed 308 people, injured over a thousand more and made 65,000 homeless. Earthquakes mark the history of L’Aquila, as the city is situated partially on an ancient lake-bed that amplifies seismic activity. The first recorded quake was on 3 December, 1315. Other earthquakes struck in 1349, 1452, 1461, 1501, 1646 and 1703 collectively-killing over 3000 people. The most serious earthquake in the history of the town struck on 31 July, 1786, when more than 6,000 lost their lives. For a town like L’Aquila, whose historical death-toll is now over 10,000 the ability to forecast earthquakes and to withstand them really is a matter of life and death.

As a forecaster myself (albeit predicting radiation in the Earth’s Van Allen belts), imagine my shock when I read the following article in Nature last week:

Scientists are not politicians. We do not enforce building codes of practice or make evacuation decisions. We simply measure, analyse and provide data to those who are responsible for such protocols. The worse thing a government can do is to gag a scientist, a theory, a hypothesis or data. One day they may save our lives.

Ian Main from the Department of Geology and Geophysics of the University of Edinburgh, in his excellent article in Nature Debates entitled, “Is the reliable prediction of individual earthquakes a realistic scientific goal?” writes,

“Despite significant global efforts into understanding earthquakes, they continue to strike suddenly and without obvious warning. Not all natural catastrophes are so unpredictable, however. For example, the explosive eruption of Mount St Helens in 1980 was preceded by visible ground deformation of up to 1 metre per day and by eruptions of gas and steam. The general public had been given official warning of the likelihood of the eruption months before.”

If other sudden-onset natural disasters can be predicted to some degree, what is special about earthquakes? Why have no unambiguous, “reliable” precursors been observed? I put the word reliable in quotes because things are always only reliable to some degree. And because, like with Giampaolo Guiliani’s “unreliable” radon emission precursor, an evacuation would have saved hundreds. Predicting earthquakes based on radon emissions has been studied by scientists since the 1970s, but enthusiasm for it had faded due to inconsistent results. But, when December 2009, Giuliani presented his research to the American Geophysical Union in San Francisco; the union subsequently invited him to take part in developing a worldwide seismic early warning system. On his return home, the Italian authorities lifted the gagging injunctions against his predictions. As science vindicated Guiliani, science should also defend the 6 on trial in Italy. Earthquakes simply cannot be predicted (yet) and we scientists should not pay the price for the failures of politicians to safeguard citizens.

Image Credit: Panorama.it

There are many accounts of successful predictions, unfortunately there are a larger number of false predictions. This does not mean that the growing awareness of various types of earthquake prediction techniques including the use of animals, analysis of cloud formations, radon or ultra low frequency emissions should be gagged, abandoned or subject to negative propaganda. Statistics, done properly doesn’t lie. And lies are always exposed in the end. My advice to the citizen is to read the preparatory guidelines of the U.S. Geological Survey, listen to a spectrum of opinion and make your own mind up. Your own common sense may just save your life. Failing that, make your own detector. The best tribute to the lives lost in L’Aquila is to keep alive the hope that it can be prevented in the future. Be safe everyone.

Image Credit: Earthquake Country Alliance

Image Credit: Jochen Lueg