Italian scientists are planning the final tests of a sophisticated earthquake forecasting system, which may one day support a weekly forecast of potential death and destruction from quakes. Italy’s civil defence authorities are debating how to use the system and communicate the forecasts to the public.
According to Ian Main of the University of Edinburgh, UK, the problem is that despite a huge effort, researchers have yet to find a signal that reliably predicts individual earthquakes.
The magnitude-6.2 earthquake in Italy on Wednesday – with an epicentre only 45 kilometres from l’Aquila – was not preceded by even one warning tremor, says Warner Marzocchi, head of the Italian National Institute of Geophysics and Volcanology in Rome.
Based on this, Italy is installing a national system that feeds seismic monitoring data into mathematical models of historical data to predict, every 3 hours, the likely number of quakes in the coming week. The system should be especially good at predicting aftershocks, such as the magnitude-4.3 tremor that hit the central Italian quake zone on Thursday. The bigger the quake, says Marzocchi, the more tremors are likely afterwards.
Italy’s Civil Protection Department must now figure out how to use these forecasts, a perennial headache for authorities faced with a slightly increased risk of low-probability but high-impact events like earthquakes, epidemics or terrorism. The system is called OEF Italy, standing for operational earthquake forecasting.