"Deadly Shadow of Vesuvius"

PBS Airdate: November 10, 1998
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Tonight on NOVA, a notorious killer. For millions in its path the clock is ticking. No volcano has left more chilling evidence of its lethal power than Vesuvius. There are signs its long silence may be coming to an end.

BARBERI: "We have confidence there is actually going to be an explosive eruption".

NARRATOR: Can scientists predict the next disaster in the deadly shadow of Vesuvius?

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NARRATOR: Naples, Italy. This ripe and teeming city is one of the most densely populated places in the world. A million people work here, play here, and love here. But they live in the shadow of a notorious killer—the volcano Vesuvius. One of the most lethal volcanos, Vesuvius always lurks in the background, silent, menacing, waiting. For the people of the region the clock is ticking.

If Vesuvius erupts, hundreds of thousands of people directly in its path will have to flee its fury. In Rome, the government prepares for a disaster of cataclysmic proportions.

BARBERI: The probability that Vesuvius will erupt again in the future is very high. We don't know when it will erupt again, but certainly it will one day erupt again.

NARRATOR: With its unbroken history of deadly eruptions there is little doubt that Vesuvius will kill again. Dozens of times in the last two thousand years Vesuvius has rent the earth and spewed burning rivers of lava. In rarer, even more lethal eruptions, it has shot jets of super heated gas, ash, and rock into the stratosphere. Falling back to earth, these clouds cascade down the mountain in blistering avalanches destroying everything in their path. For fifty years Vesuvius has been quiet, but there are signs that its long silence may be coming to an end.

BARBERI: We don't want to create any panic. We are making the maximum effort in order to monitor the volcano, and to be able to understand in advance that the volcano is ready to erupt.

NARRATOR: When will this now sleeping giant next erupt? This is the critical question for the people of this region. And no one wants to know the answer more than the scientists charged with monitoring the volcano. Lucia Civetta is Director of the Vesuvius Observatory.

CIVETTA: I feel in some way terrified. If I can imagine when the next eruption when will occur, because it will occur—it will happen.

NARRATOR: Every few months Civetta and her team descend deep into the crater of the volcano. It is a difficult climb, but Civetta must get some critical measurements.

CIVETTA: Stop. Stop. OK.

NARRATOR: It will take the team two hours to reach the bottom of the crater. Frequent small rock slides make their long journey into the mouth of the volcano more treacherous.

The team arrives at the floor of the crater. The steaming fumaroles, or gas vents, they find are evidence of a huge chamber of magma, a bubbling reservoir of molten volcanic material hidden miles underground. Before an eruption, the magma will begin to advance upwards causing an increase in temperature. A reading of 88.3 C—about 190 Fahrenheit—shows no significant change.

Next, they sample the gasses that seep from magma beneath the crater. The most prevalent are carbon dioxide and hydrogen sulfide. In large quantities these gasses can be poisonous. Here, in small amounts, they provide a window into the deep inner workings of Vesuvius. These samples will be sent off to a lab for analysis.

For Civetta, an inexperienced climber, the 1000-foot ascent is arduous. At the crater's rim she is cheered on by Giovanni Orsi, fellow volcanologist and her husband. These two spend a lot of time on volcanoes.

ORSI: We have some common problems, but sometimes it's tough. The risk you run is you only talk about volcanology.

NARRATOR: Civetta and Orsi share a huge responsibility, to protect the people of this intensely volcanic area of Southern Italy. While Civetta takes the lead on Vesuvius, Giovanni Orsi monitors another less well-known volcanic region. Ten miles to the west of Vesuvius are the Phlegraean Fields. Thirty-four thousand years ago a massive volcanic eruption formed this eight mile wide depression, or "caldera".

ORSI: "In the foreground down there is Vesuvius - and between Vesuvius and the caldera is the town of Naples".

NARRATOR: At the rim of this caldera only dimly visible is the edge of Naples, well within the reach of some of the forty small volcanoes that border the Phlegraean Fields. The most active of these is La Solfatara, Sulpher Earth. This is the gateway to the underworld, at least according to the ancient Romans. It is claimed as the inspiration for Dante's Inferno.

In 1314 Dante wrote: "The foul-stretched marsh surrounds the dolorous city to its furthest bounds. Without, the dense murk, the bubbling mire. Within, the white-hot pulse of eating fire."

This crater has been bubbling and steaming for thousands of years. Giovanni Orsi's team comes to La Solfatara every week to assess the temperature and the composition of the volcanic gasses.

The temperature reading quickly rises to double that of Vesuvius. 165 C—or 329 F. Orsi monitors the volcanic gasses that escape from the earth here at a higher rate as well. A tube runs from the fumarole to a glass chamber where sulpher dioxide and hydrogen sulfide gasses are collected. The team pours ether over the chamber to cool the gas and keep it from expanding. They work quickly because these fumes can be noxious.

Recent readings of gas levels at La Solfatara are three times higher than at Vesuvius and demand frequent inspections. These samples will be analyzed and compared to levels from previous weeks.

ORSI: "We are inside the crater of the La Solfatara volcano. At the moment is the most active volcano. As you can see, all the steam and also hot gas coming out of the ground".

NARRATOR: The steam and gasses strongly suggest that the volcanic material hidden below this crater is volatile. And there is another warning sign—frequent small earthquakes.

ORSI: We have had a lot of earthquakes and we have had radiation (inaudible) and composition of the fumaroles. All these signs can be interpreted as precursors of an eruption. If you look behind me you will see a lot of houses just on the rim of the volcano. And this gives you a feeling of the risk—of the volcanic risk in this area. In both areas, here and in the country of the caldera in the Vesuvius, the volcanic risk is very high because of the very high number of people living in the area. We are almost two million people in this area.

NARRATOR: La Solfatara is on the outskirts of Pozzouli, a city literally on the move. Here is another warning sign of a possible eruption. As the magma chamber underground slowly rises, it pushes the land upwards. The sea appears to fall, but it is the town that is rising.

Orsi surveys the harbor front. In the last thirty years the ground here has risen more than eleven feet. In the center of the town the ruins of Serapis, an ancient marketplace, reveal dramatic visual evidence of this kind of ground uplift.

ORSI: "What is important from a volcanological point of view in this building is the three columns".

NARRATOR: These columns are marked with burrows made by sea mollusks, proof that since the columns were constructed two thousand years ago they have been periodically submerged.

ORSI: "It's a good record of the vertical movements of the area".

NARRATOR: The last eruption in this region was in 1538. Someday there will be another eruption. Only its timing is uncertain.

The Phlegraean Fields bordered by simmering La Solfatara and dozens of other craters is an active volcanic region. The ill-fated city of Naples sits smack between two volcanic threats—the Phlegraean Fields to the West and to the East the giant Vesuvius. In both regions the clock is ticking to an eruption. But when will it happen and how big will it be?

Back on Vesuvius, some people implore a patron saint to guard against the volcano's coming fury. But the team from the observatory prefers to rely on more scientific methods. They are searching for signs of ground uplift around Vesuvius.

Today, they visit one of twenty sites on the mountain to measure variations in gravity. If there is even the smallest ground uplift, sensitive gravity readings will reveal it as a slight change in the density below the mountain's surface.

Today, readings indicate no evidence of ground uplift. But there is one suspicious warning sign. Several hundred micro earthquakes occurred on Vesuvius in recent years making this the most active period in more than half a century. This probably represents normal background fluctuations. But could it be a precursor to an eruption? If the past foretells the future, increased seismic activity might mean the worst.

Fifteen miles from modern Naples are the ruins of another Roman city, Pompeii—destroyed by Vesuvius 2000 years ago. Here there is testimony to the power of the volcano. Walls crumbled. An entire city vanquished. Hidden amidst the ruins is evidence of the warning signs that led up to that deadly eruption.

The historical record describes a massive earthquake in 62 A.D. There are also signs that in the years and months that followed many other small tremors shook Pompeii. There is evidence of repairs made to walls and frescos, including 2000-year old piles of lime. But the ancient Romans did not know that these earthquakes foreshadowed one of the worst volcanic disasters in all of history.

It happened on August 24, 79 A.D. The day dawned clear and hot in Pompeii, a jewel of the burgeoning Roman empire. Merchants and manufacturers prospered in the city of 20,000. The region was rich with vineyards and orchards. The early Romans were unaware of the price for this bounty. They did not realize that the black fertile earth they cultivated was a legacy of the mountain of the west—a volcano that spewed forth destruction every few hundred years. So they thought little of the tremors that interrupted the morning's peace. But later, something went horribly wrong.

From across the bay, a seventeen year old youth watched as Mount Vesuvius turned into a fuming monster. Later, he recorded his observations.

YOUTH: "A cloud appeared of unusual size and shape. Hot as and pumice stones broke in upon them. The people covered their heads with pillows, the only defense against a shower of stones. My mother beseeched me to make my escape in any manner I could. You might have heard the shrieks of women, the moans of children, and the outcries of men. A dark and horrible cloud charged with combustible matter suddenly broke and set forth. Some bewailed their own fate. Others prayed to die".

NARRATOR: The darkness that fell over the city would last for almost 2000 years. In the eighteenth century, the men, women, and children who had been silenced in 79 A.D. were finally exhumed from their untimely graves. During the excavations, archaeologists created plaster casts around their skeletal remains capturing details of the precise moment of their death. What can these victims reveal about the last hours of Pompeii? Were they suffocated? Burned? Buried alive?

The remains of the more than 2000 people found amidst the ruins offer clues to the savagery of Vesuvius and of its potential to kill again. In destroying Pompeii, Vesuvius also preserved it. The vast ruins are a natural laboratory—a moment frozen in time. For volcanologists this crumbled city opens a window into the destructive force of one of history's most perplexing disasters.

SIGURDSSON: "When I first went to Pompeii in 1979, I was struck by the fact that this important eruption, and perhaps the most famous eruption in history, had really been neglected and not interpreted properly".

NARRATOR: Haruldar Sigurdsson wanted to understand more about the eruption and the exact sequence of events that took the lives of so many. The first step was to figure out exactly how the people of Pompeii were killed. For insight into the events that destroyed Pompeii, Sigurdsson turned to an ancient document, the only eye witness account of 79 A.D., The Pliny Letters—written by the youth who had watched the eruption from across the Bay of Naples.

From relative safety, Pliny, the nephew of a naturalist, carefully noted the timing of the 18-hour eruption, the shape of the mushroom cloud, the showers of volcanic ash and rock. But one chilling detail had long been thought to be an exaggeration.

PLINY: "On the other side there was a dark and horrible cloud charged with combustible matter. Not long after, the cloud descended".

SIGURDSSON: During the climax of the eruption, Pliny Younger describes a black cloud that rolls down from the volcano and over the ocean. Now, to many scientists, or to many volcanologists, this would seem impossible until very recently.

NARRATOR: It wasn't until they witnessed more contemporary eruptions of other volcanoes that scientists understood what Pliny had observed 2000 years ago—the dark and horrible cloud was probably what is now called a pyroclastic flow.

Mount St. Helen's 1980, scientists watched as a blistering wave of hot ash, rock, sulpher dioxide, and other gasses hurled laterally and downward at great velocities, burning and destroying everything in its path.

El Chichon, Mexico, 1982, a large pyroclastic very much like Pliny had described. First, molten material, mainly ash and rock fragments shot 20 miles high to form a towering mushroom cloud. Later, when the energy of the blast was no longer strong enough to keep this dense column aloft it collapsed and cascaded down the mountain in convulsive waves. Super heated ash churned around heavier ground hugging gas and rock in a racing, burning avalanche.

Pyroclastic flows have overtaken cars travelling at 80 miles an hour. They have flattened entire villages and scorched everything and everyone caught in their path. Perhaps it was this kind of eruption that annihilated Pompeii.

SIGURDSSON: "A new science developed of the understanding of pyroclastic flows and it became obvious that similar processes are taking places in 79 A.D."

NARRATOR: But how well does the extensive archaeological record in Pompeii support this understanding of the 79 A.D. eruption? Anthropologists Maceij and Renata Hennenberg travelled ten thousand miles from Australia to examine the remains of a family discovered in a house off one of Pompeii's main streets.

The Hennebergs returned the skeletons excavated from two rooms here to the exact location and poses they held in the moment of their demise.

MACEIJ: "...and the right one as they were extended"....

NARRATOR: At this "murder" scene, archaeological drawings are the chalk marks around the body on the street.

MACEIJ: "..the right one was quite in place and articulated"...

NARRATOR: The position and condition of the skeleton offers clues to the cause of death.

MACEIJ: "So we can say with confidence that the entire person was buried here".

NARRATOR: Who were the people who lived here and died here? Why did they remain when so many others fled the city during the early hours of the eruption?

MACEIJ: "Apparently, the family decided to sit it out rather than to run. And they locked themselves into those two strong bedrooms with probably very strong wooden doors and tried to simply wait out what would happen. The elderly gentleman on the bed and the young boy tried to hold hands, hanging on for their lives".

"The volcanic ash came in and the air temperature rose. The fumes and volcanic gases started coming in and these people suffocated."

"We see the movements of their bodies, the last intentions of those people who failed to sit it out, and who succumbed to this rather dreadful, but quite fast death".

NARRATOR: Protected by thick stone walls, the family waited out the rock showers only to be suffocated later by volcanic gases and ash. In the courtyard of this once grand residence, the Hennebergs create a facial reconstruction of the patriarch of the ill-fated household.

MACEIJ: "....the width of the orbit"...

NARRATOR: First, they take the dimensions of his features.

MACEIJ: "... and the height of the orbit will be 33"...

NARRATOR: A computer program turns these measurements into a vision of the face that once was.

MACEIJ: "There is no way to predict the future except to look back into the processes of the past. And, therefore, we learn from the dead about our future.

NARRATOR: As they "flesh out" these characters the story of Pompeii comes once more to life. Here was a large family of prosperous Romans unwilling or unable to flee their home and save themselves. They succumbed to a horrendous end: death by suffocation in a cloud of ash and gas.

But many of their neighbors suffered an even more grizzly fate. At an on-going excavation site in Pompeii the mangled remains of two young women were found scattered in the street—mowed down as they tried to escape.

VARONE: "The surge that encircled these women wrapped them in a cloud in which there was no possibility for them to breath at all."

NARRATOR: The women choked to death on the cloud of hot volcanic ash and gas. But Vesuvius was not yet finished with them. A moment later the heavier pyroclastic flow washed over Pompeii with a destructive of a tidal wave.

VARONE: "The flow sliced this woman's cranium perfectly in half. It scooped up shingles and beams and violently smashed them into her body as she lay on her side. The force of this flow was incredible. Not only was half her cranium missing, but her left arm and left leg were missing as well".

NARRATOR: First she was suffocated, then dismembered as she fled unprotected in the street. Eight miles from Pompeii and on the western edge of Vesuvius is Herculaneum. This ruined city offers more evidence of the force unleashed by the 79 A.D. eruption.

The metropolis of 5000 was once a resort for Roman war heroes and nobility. In Herculaneum, named for the mythic Hercules, are the relics of opulent villas and grand Roman baths. Here too are the remnants of a pyroclastic flow of incredible power. A heavy stone basin rammed across a room. A monster wave of searing ash and rock that engulfed everything in its path. Only six skeletons were found in the blanket of volcanic debris that covered the city. And for centuries archaeologists believed that Herculaneum citizens had escaped.

Then, in 1982 a worker found a chamber buried near the old beach front. In and around these chambers, hundreds of skeletons. Many with ghastly burn marks were exhumed from deep deposits of ash and earth.

In his library of skulls, physical anthropologist, Luigi Capasso, examines the remains of a young woman found in the seaside chamber. Capasso calls skeleton E-52 the "baby never born", for at her death this woman was seven months pregnant.

Her skull is scrutinized for clues to the exact nature of the fate that befell her and her unborn child. Under a microscope he finds a few 2000 year old hairs—a surprise because the hair of most of the victims was incinerated by a burst of heat. Vesuvius branded many skeletons with unique black scorch marks. In his post- mortem, Capasso and his assistant painstakingly map the burn patterns in order to understand the nature and magnitude of the heat source that charred these bones.

CAPASSO: "This person in the moment in which the burst of hear arrived has his entire face exposed to the highest temperature. At the same time, there is a well-defined difference between the right hand and the left hand. This makes you think that the man tried to defend himself from the burst of heat, maybe putting up the right forearm and hand to protect himself".

NARRATOR: But there was no escape for the people of Herculaneum, scorched and suffocated in the burning surge cloud and then buried under a mountain of pyroclastic debris. The ancient Romans were witness to one of the most terrifying natural disasters of all time. The gruesome fate that befell them offers a rare look at the complex chamber of horrors of death by volcano.

But does their demise foretell the toll of Vesuvius's future eruptions? Miles from the human remains and ruins of Pompeii and Herculaneum, a record of the eruption of 79 A.D. is permanently inscribed in the walls of a quarry. Haraldur Sigurdsson travels here to study the layers of rock deposits left by that eruption.

SIGURDSSON: "Each layer is like a leaf in a book. You can see the strata, the layers, and the story that the layers were offering us".

NARRATOR: The rock layers here, from bottom to top, are a chronology of the infernal 18 hours that destroyed Pompeii.

SIGURDSSON: "At this locality we have a fairly complete section of the volcanic deposit from 79 A.D. We start at the base with a Roman soil, beautiful, rich soil. And that is overlain by this two centimeter layer, which is the first explosion—probably the night before the main eruption.

Towards the upper part of this layer, we see that the pumice is getting darker, and it's starting to begin to form the gray pumice. And then that is overlain here by a surge, this dark gray layer that doesn't look very conspicuous, is actually the most deadly part of the eruption. So if there had been any people at this locality, they would have been killed at this particular event right here".

NARRATOR: This indelible geological record correlates precisely with deposits from contemporary eruptions, like Mt. St. Helens and El Chichon—proof that what occurred in 79 A.D. was a pyroclastic eruption.

Now, geology, archaeology, and history come together to paint a detailed picture of the death of Pompeii and Herculaneum. At noon on August 24, 79 A.D., the peak of Vesuvius explodes propelling a 12-mile column into the stratosphere at twice the speed of sound.

For the next twelve hours, pumice and ash fall from this cloud onto Pompeii. But a westerly wind protects Herculaneum. When the material becomes too heavy the massive column begins to collapse. A giant cloud of hot ash and gas surges down the western flank of the volcano engulfing Herculaneum, scorching and suffocating its people. Immediately, it is followed by a ground-hugging flow of heavier ash and rock, which buries the city.

Eight miles away, Pompeii is unaware of the fate of its neighbors. A series of surges and flows on the eastern flank of Vesuvius does not reach the city. But in the early morning of August 25th, a surge of toxic gas overcomes Pompeii and asphyxiates all who remained. The flow of rock and ash that follows knocks down buildings and buries the dead. Eventually, the city is completely obliterated.

The crumbled cities of Herculaneum and Pompeii were rediscovered three hundred years ago, and today are still being dug out from the deep volcanic blanket that engulfed them.

Since 79 A.D., Vesuvius has had dozens of other eruptions. The last large pyroclastic eruption was in 1631. Thousands ran for their lives. Many didn't make it. After such large eruptions, Vesuvius enters a repose period. But even in repose the volcano is not sleeping. It is building up a reservoir of molten material deep below the crater. These periods of repose are punctuated by effusive eruptions—surges of hot lava, and sometimes burning ash.

The last of these effusive eruptions was in 1944. The 2nd World War raged when Vesuvius put on that show. As lava crept into the town of San Sebastiasno, allied troops evacuated the inhabitants. But the U.S. armed forces could not save their city.

San Sebastiano has been re-built atop and around the lava flow that destroyed it more than fifty years ago. Since then Vesuvius has been eerily quiet. But the people here realize that the threat has not disappeared, that the volcano might be gearing up for an even bigger eruption. The flanks of Vesuvius bear deep scars from the eruption of '44. To better understand the behavior of the volcano, Director of the Vesuvius Observatory, Lucia Civetta, comes here to study its past.

CIVETTA: "The past teaches us a lot of things. To study and to try to improve the knowledge or the past history of the volcano, to understand its future behaviors. This is the major responsibilities of the Vesuvius Observatory."

NARRATOR: Was the 1944 eruption the end of a cycle? Or does it mark the beginning of a new cycle of larger more violent eruptions, like that of 1631—or even 79 A.D.? Civetta examines remnants of the past eruptions to search for signs of what Vesuvius will do next.

And there are other clues to the future behavior of the volcano. Somewhere, deep beneath Vesuvius is the magma chamber. This is the reservoir where molten material collects. Above the chamber is the critical pathway to the surface—the conduit. The size and location of the magma chamber and the condition of this conduit hold vital information about the future behavior of the volcano.

A team of geophysicists from the University of Naples has the job of mapping Vesuvius's deep uncharted inner space. They've come to the volcano to escape the scale of its next eruption. Will it be effusive with lava as in 1944? Or explosive with pyroclastic flows of gas, rock, and hot ash as in 79 A.D.?

Domenico Patella and his team use the conductivity of the earth to image the volcano.

End SideNARRATOR: They shoot electrical currents from a portable transmitter to a receiving station. The receiver records measurements of the distance these currents travel and the resistance encountered. The team gathers similar sounds from a grid of sites to build a data base about the core of Vesuvius.

Back in his lab, Patella analyzes measurements from recent field work. His research suggests that there is a medium size magma chamber three to six miles below the crater. But there is one heart-stopping finding. The team identifies a rock plug at the top of the conduit. Other experiments confirm this alarming discovery. This obstruction in the conduit, the pathway from the magma chamber to the crater is serious news for Naples.

PATELLA: "I make an analogy between a bottle of champagne and the activity of a volcano. In a bottle of champagne the liquid resides with lots of gas under pressure. When the pressure is high and the cork pops we have an explosive outpouring of liquid".

NARRATOR: This new finding leads scientists at the observatory to a very somber conclusion.

CIVETTA: "So now the conduit is obstructed; the magma chamber is deeper. I think there is a high probability that the next eruption will be an explosive eruption".

BARBERI: "The kind of an eruption that we expect is so violent and so quick in its evolution".

ORSI: "We are quite confident very likely that the eruption is going to be an explosive eruption".

SIGURDSSON: "In my opinion, the longer the repose period, or the longer the dormancy period, the greater the likelihood of a very large eruption".

NARRATOR: Perhaps an eruption on the scale of 1631, or even 79 A.D. Photographs of victims of contemporary eruptions are compared to the human remains in Pompeii by a doctor on a gruesome mission.

Peter Baxter has witnessed the many ways a massive eruption with pyroclastic flows can kill. He calculates Vesuvius's casualty projections.

BAXTER: "There's likely to be first of all an area of total destruction close to the volcano. Further out, another zone would be where the buildings and people would be under extreme temperatures from the flow, and again, the risk to life would be very great. But there's a third zone further out from the volcano which could involve a large area where the effects would be not so much from heat but from a high concentration of particles which could asphyxiate people and cause lung injury".

NARRATOR: Six hundred and fifty thousand people live in the death zones around the volcano.

BARBERI: "The only way to protect people is evacuation of these persons from the area where they live before the onset of the eruption".

NARRATOR: But because the warning signs can begin months or even years before an eruption it is difficult to know for certain when one is eminent. Few understand the problem this presents as intimately as Franco Barberi.

BARBERI: "The major difficulty here and on any other volcano in the world is that we don't have any capability of assessing the precise moment of the eruption".

NARRATOR: In 1985, Barberi travelled to Columbia to help monitor another restless volcano, Nevada Del Ruiz. He and others proposed a plan to move thousands of people out of its path. A few weeks after his return to Italy, Barberi received a letter from the Columbian authorities thanking him for his proposals which they had not yet implemented. The letter arrived one week after the volcano erupted. Rescue teams were able to save some people, but thousands more perished.

BARBERI: "Well, the Nevada del Ruiz tragedy was certainly one of the worst experiences I personally had. This is a terrible experience. Should this measure had been taken we would have saved nearly 25,000 persons that lost their lives".

NARRATOR: Barberi's sobering personal experience fuels his drive to protect Greater Naples from non one, but two, menacing volcanic regions: Vesuvius and the Phlegraean Fields. He now spearheads a new emergency evacuation plan. It is intended to protect the communities directly in the volcanos' line of fire. Under Barberi's leadership the Ministry for Civil Protection prepares for the worst.

They know there is high probability that the next eruption will be explosive and immense. They know more than half a million people live in the path of the killer volcano, and they know that to pinpoint the exact timing of the eruption is nearly impossible. Based on the assumption that it will take seven days to evacuate, it is their job to sound the alarm and begin the massive exodus.

To evacuate the region en mass, to order people to leave homes, businesses, and large sections of the city empty, to shut down commerce, industry, to tear apart the daily lives of so many is almost unthinkable. But the alternative is even worse. As the giant Vesuvius begins to yield the secrets of its dark past and deep inner workings, scientists try desperately to predict its future—For it's not a question of if Vesuvius will erupt again, only when.

Can evacuation plans work in time? On NOVA's Web site, find out about one that succeeded in saving thousands of lives.

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