Fail to warn and go to jail?!? Maybe! Italian Earthquake Trial Focuses on Probability and Public Panic
There is an amazing manslaughter trial going on right now in Italy. Six seismologists and a government official in the central Italian city of L’Aquila are on trial for what the authorities say was a failure to warn the population before a deadly 2009 earthquake. What?!?!?!
One thing the trial has done it to focus attention on the gnawing problem in disaster and earthquake-prone regions around the world: how to effectively communicate the risk of potential disaster. It is true that scientists and government officials have difficulty telling the public what they know about the risk of earthquakes in ways that help them prepare without freaking them out.
Earthquakes differ from other types of natural disasters. Meteorologists can track a hurricane with precision, but seismologists cannot predict exactly when and where an earthquake will occur. Scientists have condemned the Italian prosecution for this reason, saying the defendants are on trial for failing to do something that is impossible.
What seismologists are increasingly able to do, however, is forecast the likelihood that a quake will occur in a certain area over a certain time. Statistical analysis shows, for example, that some seismic activity — a minor quake or a swarm of very small ones — increases the probability of a larger, destructive earthquake in the same area.
That is the very question now being debated in Italy. Months before the L’Aquila earthquake on April 6, 2009, the area had experienced an earthquake swarm. A subsequent earthquake killed over 300 people. That probably increased the likelihood of a major earthquake in the near future by a factor of 100 or 1,000. There is one slight complication in this story. At the same time, a local man who is not a scientist issued several predictions of a large earthquake — specific as to date and location — based on measurements of radon, a radioactive gas that is released as the earth moves. These predictions, none of which proved accurate, increased public anxiety in the city to such a fevered height that the Italian government convened a group of a national risk-forecasting commission, including the seismologists and the government official, in L’Aquila on March 30.
At the meeting, the seismologists noted that it was possible, though unlikely, that the seismic activity could be a sign that a larger quake was imminent. They also noted that there was always some risk in L’Aquila, which has a history of earthquakes. But in a news conference afterward, the message to the public became garbled, with the government official assuring that there was no danger. The statement by the official, who is not a seismologist, reassured the citizens about a subject he is not an expert in, and the public chose to believe him.
What is the lesson from this current Italian drama?!? Communicate clearly, communicate a strong and on-going preparedness message and don’t provide assurances that are beyond your ability or knowledge in order to provide comfort to an anxious public. The best way to deal with the anxiety is to get ready!