The regions on the Tyrrhenian Sea are those most at risk of tornadoes in Italy

Far from rare. By now, in some regions in particular, tornadoes in Italy are much more common than we think. This is told by a new study published in the journal Atmospheric Research by researchers from the Institute of Atmospheric Sciences and Climate of the National Research Council (Cnr-Isac) which, in addition to confirming how the Mediterranean area is increasingly affected by these high intensity atmospheric phenomena also due to climate change, has identified which Italian regions are most at risk. Among these, for example, there is Lazio, which, as the authors say, can be defined as a real hot-spot for these events.

But why tornadoes in Italy are increasingly common ? As explained by Cnr-Isac, over the years the intensification of these phenomena "is also conditioned by the climate change in progress, as it is confirmed that there are specific forcings, such as the surface temperature of the sea, with an important role in the development of such events ". As for the Tyrrhenian Sea, for example, among the atmospheric conditions that can favor the birth of a tornado there is on the one hand an area of ​​low pressure on north-western Italy, both at altitude and on the surface, and from the other the south-western ground winds capable of carrying warmer air to the affected regions.

To understand this, the researchers analyzed the data available from 1990 to 2021 and identified 445 high intensity tornadoes, recorded in the 32 years under examination, which struck all of Italy. From the analyzes it emerged that there are specific areas most at risk, especially the central regions bordering the Tyrrhenian Sea, such as Lazio, but also Puglia, Calabria and the Po Valley. “The central Italian Tyrrhenian regions can be defined as a hot-spot for tornadoes in the Mediterranean area”, comment the authors Elenio Avolio and Mario Marcello Miglietta. “The statistical analyzes were conducted by analyzing both measurements (radio soundings) and outputs from large-scale models (re-analysis), in order to identify the dominant atmospheric conditions associated with the tornadoes identified. It was therefore possible to define specific prevailing atmospheric configurations, potentially favorable to their development in the area under study ".

In particular, the researchers focused on a tornado that hit the Lazio coast on July 28, 2019 to be able to reconstruct and identify, through high-resolution numerical simulations, the dynamic characteristics of the atmospheric phenomenon. "The results showed how it is possible to successfully predict high values ​​of specific indicators of atmospheric instability and deep convection typical of tornadoes, as well as to correctly simulate the structure of the convective cells responsible for the genesis of such events", concludes Avolio, underlining how “an integrated modeling / observational meteorological system dedicated to monitoring and operational forecasting of such intense phenomena is important”.