The following are the sea temperatures registered last Friday: 29 degrees in the Ligurian Sea and the sea around Corsica, Sicily and Malta.

These temperatures are four to five degrees higher than normal. Such high temperatures have been the norm for the past days in the western Mediterranean.

The cause of these high temperatures is the African anticyclone, a weather anomaly, which has persisted since the beginning of this millennium.

Apart from destroying the glaciers, the anticyclone, or, as it is known in Italy, Il Gobbo, is heating to an almost worrying degree the sea around us. In some areas, one can already find changes in the sea’s ecosystem, with the arrival of fauna that is more adapted to live in tropical waters than in the Mediterranean.

It is now 20 days since this curtain of heat from Africa has been beating down. The sun’s rays descend almost perpendicularly on to the sea. There are no winds, nor currents to move the water, which as a result remains static, almost stagnant.

What’s more is that this situation has already occurred this year, in spring when instead of the usual storms and depressions, the Mediterranean became like a marsh with neither air nor sea currents. Naturally, the temperatures then were lower than they are now, but what was worrying was the absence of movement.

What will happen now? It is difficult to predict. Usually we think that such warm weather presages autumn storms.

But not necessarily so. If the months of September and October see many windy days from the north, the sea would lose its heat surplus gradually, without any shocks, as happened in 2003.

But if we get an ‘old style’ autumn, with many currents coming from the Atlantic, then there is a heightened risk of heavy autumn storms, hitting especially the areas in the west of Italy, like Liguria, Toscana, Lazio, Campania. In this case the surplus thermal heat is transformed into electric and mechanical energy, with the sea storms functioning as real “transformers”.

In conclusion, a very warm sea is not always a harbinger of autumn storms and much rain. It’s like having a bomb near your house: the risk is there, but if the fuse is not lit, there is no explosion.