“Medicane”, the Mediterranean cyclone: ​​what it is and how it is formed

The disturbance that is affecting southern Italy, in particular Calabria and Sicily, has a name: ‘Medicane’. “It is a cyclone that develops in the Mediterranean – Enrico Scoccimarro, expert on extreme events and climate scenarios at the Euro-Mediterranean Center Foundation on climate change, explained to Corriere della Sera – has certain characteristics of a hurricane and is called Mediterranean Hurricane, hence Medicane “. To date, in eastern Sicily, there are two victims and one person missing. According to some experts, however, the cyclone has yet to finish releasing all its energy. Meanwhile, as the mayor of Catania Salvo Pogliese writes on Facebook, schools remain closed today.

Like a little hurricane

As Scoccimarro says, “our latitudes are usually affected by extra-tropical cyclones”: vortex atmospheric depressions that take energy “from the temperature gradients of the atmosphere”. The Medicane, on the other hand, “has a mixed structure”: in fact, it resembles tropical cyclones that take energy from the oceans, but “with smaller dimensions and a diameter of about 300 kilometers”. As for their danger, they can be compared to “a category 1 hurricane”: winds of about 119 km / h that can cause some damage (Hurricane Katrina, for example, falls into category 5). Unlike hurricanes which can last up to 2 or 3 weeks, Medicane “are phenomena that run out in a few days”.

Consequence of global warming?

It is difficult to say whether this Medicane is a consequence of global warming: “They have only become evident since we have the satellite images”, explains Scoccimarro, “before they were classified as normal perturbations. In the last twenty years we have counted about thirty: a number too limited to make an accurate statistic and to say if they have increased compared to the past “. What is known is that due to their nature, these cyclones are generated between late summer and early autumn. In particular, they are born on the African coasts, where the sea reaches a temperature of 26 ° in this period, and then hit “above all Greece, Sicily and Calabria. But they can also invest Sardinia and Salento ”.