Just 10 kilometers from the frenetic pulse of central Naples, in stark contrast to the Italian city’s impressive volcanic-stone churches and effortlessly stylish urbanites, sits a boxy, concrete building. Inside this unremarkable government outpost, accessed through a pair of sliding glass doors, is the Vesuvius Observatory monitoring room, lit by the cool glow of 92 flat-panel screens. On each screen, volcano notification systems, including those from seismic devices sensitive enough to pick up a passing bus, blink and beep in real time. In the middle of the room is a desk. And in the middle of that desk is a single red phone.
Twenty-four hours a day, 365 days a year, there are at least two people in the room, ready to pick up the phone and advise the national civilian defense in the event of a volcano-related emergency.
But Mount Vesuvius, its iconic cone rising conspicuously on the city’s eastern flank, is not the only concern. A potentially even more destructive volcanic giant is tossing fitfully in its sleep, right on Naples’ doorstep: the caldera of the massive volcano system Campi Flegrei, which translates to the fields of fire.
If it erupts, an event some researchers feel is increasingly likely, it could be catastrophic for Italy’s third-largest municipality and the surrounding countryside. Disruptions could stretch far beyond Italy, too, affecting everything from air travel to agriculture, with ash darkening the skies over Europe and the Mediterranean. The threat comes from the west, in a pockmarked and mountainous landscape abutting Naples just beyond an elongated ridge thick with lovely villas, called Posillipo Hill. The meaning of the hill’s name, “a respite from worry,” belies the story of its formation. Posillipo is at the edge of a volcano caldera so large that to see its full shape requires an elevated vantage point. To stand within it is to be unable to see it. These calderas are born when a volcano system erupts with such force that the resulting crater, instead of merely being flattened, actually slumps downward into the ground afterward. The most powerful eruption believed to be from Campi Flegrei, nearly 40,000 years ago, launched the equivalent of 300 cubic kilometers of ash and pulverized rock skyward. The massive eruption impacted the global climate and may have helped to snuff out the last gasps of the Neanderthals. Now there are signs that Campi Flegrei is stirring once more. At surface level, the caldera is dotted with steam vents, or fumaroles. One of them, the Solfatara di Pozzuoli, has famously lent its name to fumaroles that emit sulfur — such vents around the world are now known as solfataras. But it was one of Solfatara’s less well-known neighbors, the fumarole Pisciarelli, that attracted attention in 2009. The once-insignificant Pisciarelli started to roar, bubbling mud and spewing steam. It was a hint that something was happening below ground.
