Dr Giulio Selvaggi is former Director of the National Institute of Geophysics and Volcanology (INGV). He gave the first IHRR seminar of the term on the L’Aquila earthquake and its aftermath. He is one of six scientists in Italy found guilty of manslaughter for downplaying the risk of earthquakes in the region. They are appealing the verdict. The aftermath of the L’Aquila earthquake is possibly one of the most politicised and publicised affairs of recent times involving scientists.
The L’Aquila earthquake led to the deaths of 309 people. The 2009 earthquake in L’Aquila not only revealed the unpreparedness of the city in dealing with the 6.3 magnitude earthquake, but the vulnerability of the buildings that collapsed. The fact that the earthquake took place is nothing unusual. It’s well known that L’Aquila is in a region of Italy with high risk of earthquakes. Unfortunately, the message conveyed to the general public of L’Aquila by government misinformed them about the actual risk of an earthquake occurring.
Selvaggi explained how one week prior to the earthquake he attended a meeting between The High Risk Commission (HRC) and National Service of Civil Protection (NCP) of Italy. The High Risk Commission is assigned with forecasting and mitigating large-scale risks, which includes serving as an interface between the scientific community and government. The NCP are responsible for taking action to protect the public from potential risks. The advice, however, given by scientists to the High Risk Commission, does not seem to match the message the NCP disseminated to the public.
One of the scientists with INGV, Dr Enzo Boschi, who is one of the six scientists found guilty by the court, said at the meeting: ‘It is unlikely that an earthquake like the one in 1703 could occur in the short-term, but the possibility cannot be totally excluded’. Boschi is referring to a much earlier earthquake in L’Aquila that was part of the 1703 Apennine earthquake sequence that lasted for 19 days, killing many people throughout Italy. Selvaggi also stated in one official INGV report that ‘the earthquake sequence is not going to decrease the probability of a large earthquake in L’Aquila’.
However, just before the meeting, the Vice Head of NCP in an individual interview to a local TV crew said: ‘the scientific community continues to assure me that it’s a favourable situation because of the continuous discharge of energy’. This interview was broadcasted by many local TV stations during the days after the meeting, but the HRC members learned of the interview well after the earthquake. The NCP claims that they received this concept from seismologists, including Selvaggi, but there is no record of any of them saying this, only the newspaper report that simply repeats what the NCP originally told them.
It seems likely that advice given by scientists at the meeting was simply ignored in favour of a message that was more attuned with what the NCP wanted – a public at ease — instead of what was actually the case, the risk of a serious earthquake happening in the vicinity of a vulnerable population.
At the seminar in Durham, Selvaggi argued that the L’Aquila disaster was ‘not a scientific problem, but a ‘problem with public order’. Selvaggi said ‘science had been used to supply unpreparedness’. In hindsight the meeting between the High Risk Commission and the NCP seems to have been little more than a charade with painfully real repercussions.
Prior to the 2009 earthquake residents of L’Aquila would experience tremors regularly. This was not unusual. But the day before the earthquake, a local technician (Giampaolo Giuliani) who was using a questionable method for predicting earthquakes by measuring the release of radon gas from cracks and cavities in the Earth’s crust, predicted that a large earthquake would occur in L’Aquila. The local Civil Protection responded to the contrary in another press release.
The local Civil Protection told the press that ‘no earthquakes of any kind are predicted for L’Aquila and anything else is false and with no basis’.
The message was sent to the public without consulting scientists such as Selvaggi who would have disagreed with the statement, but it was already too late. For those predicting earthquakes by measuring radon gas or through other means this was a clear message. But it was the wrong message to send to an anxious public unsure of whether a large earthquake was going to occur or not.
In reality the press conference may have been an easy way for the NCP to allay public fears, but as with the previous conference that ignored the advice of scientists involved, it back fired in the worst possible way. While it seems difficult to say what took place exactly the day of the earthquake, would people have evacuated their homes if not for the NCP’s distorted message?
Selvaggi explained that buildings in L’Aquila were known to be vulnerable as early as 1985 and that the public authorities were told this years ago, but nothing happened. The medieval city remained unprepared and during the 2009 earthquake many of its antique buildings were either severely damaged or destroyed.
In 2004 earthquake hazard maps were released with L’Aquila clearly shown in the high earthquake risk area. The sequence or ‘swarm’ of shocks that occurred before the 2009 earthquake was not unusual for this region. There was no evidence that the tremors were ‘discharging’ seismic energy or that the sequence was building into a large earthquake. In court, Selvaggi and his colleagues were accused of not informing the public that earthquakes are preceded by ‘swarms’ of shocks that take place prior to a large earthquake. But earthquakes are not always preceded by swarms, something both the prosecution and the judge did not seem to understand.
‘There are 30-40 seismic sequences every year in Italy. It’s a common way to release seismic energy, not to discharge, but to release. The statistics show that only 8 out of 1,000 earthquakes are preceded by a 4.0 mag earthquake. And in the last 8 years only one preceded a large earthquake, the L’Aquila earthquake’, said Selvaggi.
The seismic sequence that took place before the L’Aquila earthquake was not a precursor as there was no way of telling if a large earthquake was going to occur. This does not mean the risk wasn’t there (obviously it was), what it does mean is that the message that was spread by the NCP was not in touch with science. They had failed to listen to what the scientists at the meeting, including Selvaggi and other researchers with the INGV, were saying in the first place: that L’Aquila is a region of Italy with high earthquake risk; that it does receive regular sequences of shocks, but that this has nothing to do with the likelihood of an earthquake occurring; and that the risk of a large magnitude and potentially devastating earthquake should not be underestimated in this region, especially when the vulnerability of L’Aquila is taken into account.
Selvaggi said that ‘reducing vulnerability was one of the main messages we gave during the meeting’. At the trial, according to Selvaggi the judge would not have it saying it was ‘useless to improve buildings’ resistance to earthquakes’.
‘We went from discharge of energy, to discharge of responsibility’, said Selvaggi at the seminar.
What has been overlooked or blatantly ignored in this case is the fact that the scientists found guilty by the court did nothing more than provide advice based on scientific evidence, that shows clearly that L’Aquila was at risk of an earthquake occurring. The threat was there and it was known to be there for some time, but it was not known when it was going to occur. It was also known that many of the buildings in the city, not to mention the extremely vulnerable medieval buildings that were destroyed, were built prior to the implementation of building codes for earthquakes in Italy.
In Italy to this day, like many seismically active parts of the world, buildings that are in danger of collapsing during an earthquake remain. If the public authorities had listened to scientists maybe 309 people would not have been killed during the L’Aquila earthquake. If they had been listened to maybe L’Aquila would have been more prepared for a disaster we now know was inevitable, and the scientists who warned of the risks involved would not have been judged guilty of a crime they did not commit.