Cyclone Harry, record wave of 16.6 meters recorded in the Mediterranean in January

A wave 16.6 meters high, the highest ever recorded in the Mediterranean Sea, in exceptional marine conditions and with signals detectable even by seismic networks: it was the one born in Cyclone Harry, which between 19 and 22 January this year devastated the Mediterranean and the coastal areas of southern Italy, Sicily in particular.

That cyclone "represents one of the most intense meteorological-marine events ever observed in the area", states the INGV, which - together with the Cnr, Ispra and the universities of Palermo, Catania, Malta and the Colorado State University and the Royal Observatory of Belgium - has demonstrated in research how the configuration of the coasts and seabeds can "significantly amplify the effects of extreme storm surges, determining very different impacts even in areas subject to the same meteorological and marine conditions".

The study, published in the journal Communications Earth & Environment of the Nature group, develops a multidisciplinary approach that integrates climatology, meteorology, oceanography, geomorphology and seismology: the researchers reconstructed the processes that transformed an exceptional atmospheric configuration into extensive coastal flooding, erosive phenomena and damage to infrastructure.

The analysis combined satellite data, observations from buoys and tide gauges, topographic and bathymetric surveys, field surveys and high-resolution numerical simulations.

The record wave recorded in the Strait of Sicily

Among the most significant results emerges the recording of the record wave of 16.6 meters by a buoy of the Ispra National Wave Meter Network in the Sicilian Channel, between Portopalo di Capo Passero and Malta.

The simulations also highlighted wave heights exceeding 10 meters in the Ionian Sea.

The exceptional nature of the event was also confirmed by seismological analyses.

The transfer of sea wave energy to the ground has generated a strong increase in the so-called microseism, the seismic noise produced by the interaction between the sea and the seabed.

By analyzing data from 55 seismic stations distributed across the Mediterranean, the researchers detected unprecedented values ​​in many time series of the Ionian area.

"In this context, microseism is proposed as a complementary tool to traditional systems for monitoring the state of the sea, useful both for following storm surges in real time and for rereading, through historical series, how the extreme events we are witnessing compare to those of the past", explains Alfio Marco Borzi, researcher at the Department of Biological, Geological and Environmental Sciences of the University of Catania.