Seismic signature of an extreme hydrometeorological event

Abstract

AbstractFlash floods are a major treat for Mediterranean countries and their frequency is expected to increase in the next years due to the climatic change. Civil protection agencies are called to deal with increasing hydrological risk, but existing hydro-meteorological monitoring networks might be not enough for detecting, tracking, and characterizing rapidly evolving floods produced by severe convective storms. Here, we leverage seismic data from a national monitoring network to characterize the hydrometeorological event that hit central Italy and resulted in a devastating flash flood in September 2022. The spatio-temporal evolution of seismic noise highlights remarkable anomalies that culminate around 6 hours before major flooding. Our results show that seismic noise generated by different, combined processes (rainfall, wind and increasing discharge in the basin headwaters), provides precious information to support hydrological risk management. We foresee seismic approaches to complement well-established procedures to early detect the occurrence of flash floods at regional scale.