JUANA SUMMERS, HOST:
In Greek and Roman mythology, the Campi Flegrei volcano is depicted as the entrance to the underworld. Its eruptions thousands of years ago blocked out the sun, turning summer into winter. And now the super volcano outside of Naples is stirring in a way it has not for centuries. NPR's Ruth Sherlock reports.
RUTH SHERLOCK, BYLINE: In the old city of Pozzuoli outside of Naples, I join a tour group through the winding, narrow alleyways.
UNIDENTIFIED TOUR GUIDE: (Speaking Italian).
UNIDENTIFIED TOURIST: (Speaking Italian).
SHERLOCK: We listen to a guide beside a garden shaded by a tree laden with pomegranates.
UNIDENTIFIED TOUR GUIDE: (Speaking Italian).
SHERLOCK: From this hilltop, you can look out over a curving bay, the sea sparkling in the sunshine under an intense blue sky, and the island of Capri - playground of the rich - in the distance. But this immense beauty belies the danger in this region.
MADDALENA DESARIO: (Speaking Italian).
SHERLOCK: "All of us know we're living in a completely seismic area," says Maddalena Desario, a resident of nearby Naples. Mount Vesuvius, whose lava once froze in time the ancient Roman city of Pompeii, rises beside Naples. Long the muse of artists and poets, Hans Christian Andersen, during an eruption in 1834, described the lava as colossal, fallen stars. But the truth is, a much bigger and potentially more dangerous seismic giant hides here underground - the Campi Flegrei.
GIOVANNI MACEDONIO: (Speaking Italian).
SHERLOCK: Giovanni Macedonio, the director of the National Institute of Geophysics and Volcanology in Naples, describes the Campi Flegrei's giant volcanic eruption some 39,000 years ago.
MACEDONIO: (Speaking Italian).
SHERLOCK: This super volcano shot out 72 cubic miles of molten rock. Global temperatures plummeted and the entirety of Europe and even Russia were covered in volcanic ash.
MACEDONIO: (Speaking Italian).
SHERLOCK: Macedonio says scientists expect an eruption today would not be on that scale, but it could still be massive. In fact, the Campi Flegrei is considered by the Italian government as a national threat. Macedonio says it could stop air travel across Europe and even other parts of the world. And what makes this volcano even more dangerous is that today hundreds of thousands of people live right on it, in its eight-mile-wide crater.
MACEDONIO: (Speaking Italian).
SHERLOCK: Some half a million people are in the red zone, the area authorities say would have to be evacuated for people to survive an eruption. It's for this reason that Macedonio and his team monitor the volcano's every grumble and tremor.
MACEDONIO: (Speaking Italian).
SHERLOCK: Macedonio shows us the observatory with screens on every wall. They watch every volcano in the region, but recently, it's the Campi Flegrei that causes concern. And while we're there, this happens.
(SOUNDBITE OF ALARM SOUNDING)
SHERLOCK: This alarm shows that there's an earthquake happening right now.
It's in the Campi Flegrei, and that, these days, is not unusual.
MACEDONIO: (Speaking Italian).
SHERLOCK: Last year, there were 2,500 earthquakes in a single month, and the problem is, they're getting stronger. This year has seen unprecedented tremors of up to 4.6 in magnitude - enough to crack walls and send people fleeing from homes. And while this is happening, the ground is swelling, slowly rising beneath people's feet. We go to see a clear example of this at an old city port in Pozzuoli.
Boats just nestled in the grass. They used to float on water. Now they're marooned on land. It's bizarre because this is the kind of scene you'd expect from a drying lake, but this is an inlet of the sea. There is water, but the ground has risen so high that it's blocking the entry of the water from the sea.
It's as if this giant volcano were breathing, the ground rising and falling over decades with every breath. Before the last major eruption 15,000 years ago, the ground rose about 85 feet. Now it's steadily rising again, up 4.6 feet since 2005, and the rate at which it's swelling is getting faster.
WARNER MARZOCCHI: One thing that you learn very soon is that we do not have the control. Nature has the control.
SHERLOCK: Warner Marzocchi is a professor of geophysics and natural risk at the University of Naples Federico II.
WARNER MARZOCCHI: This kind of volcanic system are used to have phases of unrest, like this one that we are observing. The biggest scientific challenge is to understand what is the drive behind this unrest.
SHERLOCK: To meet that challenge, Marzocchi and his team are using artificial intelligence to build the most accurate picture yet. The technology suggests that, for now, the tremors are more the result of gases pushing superheated water up through the Earth rather than magma rising. But this is no reason to relax because, Marzocchi says, there is no guarantee that an eruption won't happen.
WARNER MARZOCCHI: It's unlikely, fortunately, but it's not zero. And in that case, we do not have any possibility to reduce the risk because we can't stop a volcano.
SHERLOCK: So what's it like to live in a volcanic crater where your life can change in an instant?
PINA TESTA: (Speaking Italian).
SHERLOCK: "Sometimes, when the earth quakes, I feel like the volcano is right under my studio," says Pina Testa, an artist in Pozzuoli. She paints volcanic eruptions - giant plumes in all colors streaming into the sky.
TESTA: (Speaking Italian).
SHERLOCK: "Fire and everything that is movement of the Earth speaks to the soul," she says. There's even a kind of affection for the volcano.
TESTA: (Speaking Italian).
SHERLOCK: She remembers, as a child, the gatherings with neighbors on the street as they left their homes during an earthquake. It was a time to chat, to catch up, even share a pizza.
TESTA: (Speaking Italian).
SHERLOCK: The real resident of Pozzuoli lives in harmony with the volcano, she says. They can get scared sometimes, but never terrified, and they do not leave. Ruth Sherlock, NPR News, Pozzuoli near Naples.
(SOUNDBITE OF MUSIC) Transcript provided by NPR, Copyright NPR.
NPR transcripts are created on a rush deadline by an NPR contractor. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.
