Volcanic vortex rings emerge from a new pit crater on the north side of the southeast crater of the Etna Volcano in Sicily, Italy. Photo / AP
Volcanic vortex rings emerge from a new pit crater on the north side of the southeast crater of the Etna Volcano in Sicily, Italy. Photo / AP
Mt Etna, Europe’s largest active volcano, is delighting tourists and residents by blowing almost-perfect circles of smoke into the blue skies over Sicily.
The smoke circles, known as volcanic vortex rings, are made of condensed gases and water vapour. They form when gases rise from deep below Earth and escape from inside the crater of a volcano.
Mt Etna is one of a handful of volcanoes around the world that produces the rings, and does so prolifically, but the latest emissions are exceptional, scientists say.
Volcanic vortex rings emerge from a new pit crater on the north side of the southeast crater of the Etna Volcano in Sicily, Italy. Scientists believe the rings are the result of a combination of fast gas release at the top of the magma conduit and regularity in the shape of the emitting vent. Photo / AP
“No volcano on Earth produces so many rings of steam as Etna. We have known this for quite some time. But now it is beating all previous records,” said Boris Behncke, a volcanologist at the National Institute of Geophysics and Volcanology of Catania. He has been studying the volcano and living close to it for the past 25 years.
He said that, on Tuesday, a small vent opened on the northeast edge of the southeast crater, and emitted puffs of incandescent gas.
The next morning, it became clear these puffs were creating “an impressive quantity” of vortex rings, he said.
The volcano has emitted hundreds, perhaps thousands, of the spectacular rings since then, said Behncke, who can see the volcano from his house in Tremestieri Etneo near Catania.
Residents have dubbed the volcano Lady of the Rings due to the circles of vapour it has been emitting.
Volcanic vortex rings emerge from a new pit crater on Mt Etna in Sicily, Italy. Photo / AP
“I thought I had hallucinations. I had never seen anything so spectacular and beautiful,” said Angela Intruglio, of Mascali, a town at the foot of Mt Etna that had to be rebuilt after it was destroyed in an eruption in 1928.
Experts say the unusual rings are harmless and aren’t necessarily a prelude to an imminent eruption.
“It’s only an open conduit of a circular shape through which the gas is shot in a pulsing way,” Behncke said. “It’s really something extraordinary and completely innocuous.”
The previous time it happened at Mt Etna was in December, said Giuseppe Barbagallo, a guide at the South Etna Alpine Guides Group. Other major emissions of rings occurred in 2000 and last year.
People look at volcanic vortex rings emerging from a new crater on the north side of the southeast crater of Mt Etna in Sicily. Photo / AP
At 3353m, Mt Etna is the tallest volcano in Europe. Eruptions have been happening for half a million years, according to Behncke’s institute, but the volcano acquired its characteristic conical shape in only the past 100,000 years.
Magma climbs up Mt Etna through a central open conduit that constantly releases gas, meaning smoke is almost always emanating from its top.
The last major eruption was in May, and forced aviation authorities to halt all flights at the nearby airport of Catania, a popular tourist destination.
At the time, the eruption of lava from its southeast crater produced a cloud of black volcanic ash that fell on the city, causing disruption not only to air traffic but also vehicles on the ground.
A volcanic vortex ring from Mt Etna in Sicily. Photo / AP
The same happened because of the eruptions of 2001 and the following two years, when a layer of lapilli and ashes formed on streets and motorways endangering road traffic. The same applied when they fell on the airport runway.
The institute also said thin volcanic dust can irritate people’s eyes, skin and throats, while crops can suffer irreversible damage due to the ashes and lapilli transported by the wind, in case of eruptions.
Many major eruptions have occurred over the past 100 years. In 1971, several villages were threatened by lava flows, which destroyed some orchards and vineyards. Over the following decade, the volcano’s activity was almost continuous. In 1983, authorities set off dynamite in an attempt to divert lava flows, after an eruption that lasted four months.
