In summer in Italy it is increasingly common to hear about air trumpets: Sunday 3 August one was recorded on the beach of Maccaresein the coast north of Rome, which swept away the umbrellas causing the escape of bathers. But on the weekend the Costa Adriaticaespecially in Ferrarese, while in the last 10 days Several trumpets have also formed in Liguria and Calabria, where they damaged boats and bathing establishments.
But because these air trumpets, often called Tornado, are so frequent in summer? To form, these air vortices need one colder air mass (brought by a disturbance) that dominates one mass of hot and humid air Close to the ground: this condition is more frequent in summer and in the hottest months of the year.
In general, it is a rather meteorological phenomenon common In Italy, which however has become increasingly intense in recent years due to global warming.
What are the trumpets of air and how they are formed
Before you can understand why in summer the air trumpets are more frequent, we must take a step back to understand how they are formed These weather phenomena. A trumpet is a violent vortex of air about 100 meters in diameter, which originates at the base of a cumulonembo and reaches the ground: these vortices can travel tens of kilometers, generating twenty up to 300 km/h.
In general, the trumpets are formed inside large storm clouds, when one Very hot column of air It rises quickly and is rotated by the colder currents that are at high altitude. That’s why the phenomenon of formation of an air trumpet is associated with the presence of a strong storm.
To form, therefore, a trumpet needs several elements: a high content of humiditythe presence of atmospheric instability and a strong variation of the direction and intensity of the wind with the share, the so -called Shear of the wind. A high shear favors a particular type of storm, i.e. the so -called Supercella temporalwhich characterizes the most intense events. When a strong storm occurs, atmospheric pressure decreases, thus creating one low pressure cell: All this can generate very violent movement of air, which “rise” the hottest (lighter) air and lead to the formation of an air trumpet.
At that point, the vortex that has formed becomes visible when the water vapor is sucked in upwards and condenses in the clouds above, taking the typical funnel form.
Because they are more frequent in summer
So to ensure that a trumpet fork must have a colder air mass (brought by one disturbance) which dominates a mass of hot and humid air near the ground: this condition is more frequent in summer and in the hottest months of the year, that’s why these air vortices are more frequent in summer periods.
Trumpets of air and tornado, then, increase in intensity if the climate is warmer and wet: Due to global warming and the laying of temperatures, the Mediterranean waters are also becoming more and more hottrapping more and more energy. The greatest energy issued by the sea generates an atmospheric instability, which is one of the basic conditions for the formation of an air trumpet.
It must be specified that these are rather common phenomena in Italy, even if in recent years they have become more and more intense. The problem is that in Italy there is still no official alert system for air trumpets: to date, in fact, the programs have not yet been developed forecast For these meteorological phenomena, which therefore cannot be anticipated precisely.
The air trumpets, then, should not be confused with the downburst, which instead are air currents that precipitate, impact the ground and spread linearly in all Directions and not vortex.
The difference between the air trumpets in Northern Italy and the South
In Italy, among other things, the formation of air trumpets also depends on the area where you find: the air trumpets southernin fact, generally develop in summer (and also in the autumn) and mostly they originate from sea trumpets that move on mainland. In this case, the vortices of air are triggered by the rapid transit of a very warm and humid air of air of African origin (which therefore favors instability conditions) and characterized by a strong rotation of the wind, which involves even more intense events.
In the Northern Italyon the other hand, the trumpets occur mainly in late spring and summer: in these cases, instability depends on the arrival of fresher air coming from the northwhich clashes with hot air rich in humidity present in the low layers during the summer season.
In other words, in northern Italy the mechanism of formation of air trumpets is more similar to what happens in the rest of the European continentwhile the vortices of air that verify in southern Italy and in the islands depend much more on marine trumpets, which then move to the hinterland.
In general, however, air trumpets tend not to form in the mountainous areaswith the exception of some foothills such as the Prealps and the Apennine hilly areas.
