I earthquakes it can be events more destructive. The earth trembles, everything that is built collapses and they are often accompanied by landslides or tsunamis. But it is not certain that they are always so dangerous: most of the time they are light shocks that cause books to fall off the shelves, and often we don’t even notice it. And they don’t just happen on our planet.
And in fact, probably no one noticed the earthquake every half an hour that shook theItaly In the 2021. Yet it happened. Better still than the earthquake that has been going on in Indonesia for years.
Earthquakes in Italy
The Italian institute that deals with tracing and taking into account earthquakes in our country is theInvg, National Institute of Geophysics and Volcanology.
Ours is a territory a strong seismic risk, certainly the one with the seismic risk highest in Europe. Territorial diversities are strong, because the risk is almost nil in the north, especially Lombardy and Piedmont, and very strong in the ridge that goes from Umbria to Calabria.
The most disastrous earthquake in Italy, by number of deaths and by magnitude, was that of Messina, on the night of December 28th 1908: a magnitude of 7.5 shook the whole strait, and in the collapses they died 120 thousand people: this is the most serious natural disaster in the entire history of Europe. Similar numbers are approaching the earthquake of Val di Noto in Sicily in January 1693, with 60 thousand dead, and another earthquake in the strait, in 1783, with 50 thousand victims.
In more modern times, we remember the earthquake of Avezzano, in the Marche, with its own 30 thousand victims after an earthquake with a magnitude 7. In 1980 the earthquake of Irpinia killed 2,914 people, but shocked an entire area of Italy that struggled incredibly to get back on its feet. In 2009 it was destroyed L’Aquila, the night of April 6: 309 people die and reconstruction proceeds slowly. How does it happen to Amateur on 24 August 2016, with its three hundred victims after a quake of magnitude 6.0.
The thousands of earthquakes of 2021
According to the Invg, in 2021 in Italy there were 16,095 earthquakes: an average of 44 per day, then one every half hour. The most affected regions were Sicily, Umbria and Marche. Sardinia, on the other hand, is almost immune.
These are numbers that could make us jump on the chair, because they are very high. But they are not worrying: just think that in 2020 there were 16,597 and in 2019 16,584. Constant numbers, therefore, and even lower than those recorded in the three-year period 2016-18: but then there was the great earthquake in Central Italy, between Amatrice, Norcia and Visso. Also in 2021 the Center of Italy was the most subject to shocks of varying intensity: the 30% of the total.
The National Institute of Geophysics and Volcanology also tracks earthquakes that occur in foreign countries but close to Italy. And for 2021 the strongest tremors, that is those above magnitude 5.0, have occurred abroad, between Algeria, Croatia and the Adriatic Sea. “However, we have also heard some of these on the Italian territory” explains Alessandro Amato, researcher at Ingv.
The first earthquake of 2021 it was a Pavullo nel Frignano, province of Modena, one hour and three minutes after the New Year. L’last, instead of a Sefro, near Macerata, half an hour before midnight. Both had a magnitude of less than 2.5.
The strongest earthquake it happened in Sicily, in Motta Sant’Anastasia, on 23 December, and was part of a swarm with 50 shocks in three days. It had a magnitude of 4.3. The smallest, and makes you smile, in Gubbio, with one magnitude of 0.0: the Richter scale for measuring the magnitude of earthquakes can also have negative values. But in that area, the most dangerous from this point of view, the most sensitive machinery and sensors are installed.