Deep underground in southern Italy, just outside the city of Naples, the Campi Flegrei supervolcano has been resting for the past 500 years. But it seems that quiet phase may soon come to an end. As Reuters reports, even a small eruption from a volcano nestled within such a highly populated area could threaten hundreds of thousands of people.
Starting in 1968, the Earth’s surface around the volcano began to bulge, lifting by a net total of three meters (nearly 10 feet). “Magmatic intrusion,” say scientists Judith Woo and Christopher Kilburn in a 2010 study, is the most likely source for the unrest.
To find out whether the uplift is the sign of an impending eruption, and to understand what makes Campi Flegrei tick, scientists have set out on a mission to drill into the crust above the supervolcano—a mission which just got underway, following years of political turbulence.
Giuseppe De Natale, the drilling project’s team leader, told Reuters that ”This will increase by a thousand or 10,000 times our ability to detect small episodes that are precursors of future eruptions.”
Worse than the threat of a localized volcanic eruption is the possibile damage the Campi Flegrei could do if it really got going. Recent research found that one of the supervolcano’s eruptions, called the Campanian Ignimbrite super-eruption, which took place 39,000 years ago, decimated vast stretches of the Mediterranean. That eruption was, until recently, implicated in the extinction of the Neanderthals. Charles Choi, writing for Our Amazing Planet:
The researchers discovered the super-eruption behind the Campanian Ignimbrite would have spewed 60 to 72 cubic miles (250 to 300 cubic kilometers) of ash across 1.4 million square miles (3.7 million square km)
he super-eruption would have spread up to 990 million pounds (450 million kilograms) of poisonous sulfur dioxide into the atmosphere. This air pollution would have cooled the Northern Hemisphere, driving down temperatures by 1.8 to 3.6 degrees Fahrenheit (1 to 2 degrees Celsius) for two to three years, enough to have severe effects on the environment.
Luckily for us, Campi Felgrei’s eruptions seem to be weakening with time, says Helen Brand, a planetary scientist at University College London. However, she adds that, “the Campi Flegrei caldera is still magmatically active and that the caldera may erupt again in the near future.”
Keeping in mind, of course, that the phrase “near future” is coming from a geologist, and isn’t being used in the colloquial sense. Which means there’s no need to cancel your Italian getaway just yet.
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