How many eruptions has vesuvius had

The gases from these surges have been estimated to have reached temperatures as high as C F , making it impossible for any remaining citizens to escape. The two letters written by Pliny the Younger to the Historian Tacitus are the only surviving eyewitness accounts of the eruption.

In the letters, Pliny the Younger describes, among many other things, the last days of his uncle Pliny the Elder.

Having witnessed the eruption from Misenum on the other side of the Bay of Naples, the elder Pliny, who was a naval and army commander in the early Roman Empire, launched a rescue fleet and went himself to rescue a personal friend. Aerial view at ruins of Pompeii. He describes how his uncle, who was in command of the Roman fleet at Misenum, ordered a rescue operation by sea. His nephew tried to resume a normal life after his departure, but the situation was growing far worse.

That night a tremor awoke him and his mother, who insisted that they abandon the house for the courtyard. The next morning the young Pliny saw lightning in a dark cloud that was obscuring the morning light. The population began to evacuate from the coast , as a thick cloud of ash began to fall on the village. The young Pliny at one point had to shake it off to avoid being buried. Later that day, the ash stopped falling and Pliny and his mother returned home to await news of Pliny the Elder.

Meanwhile, Pliny the Elder had received a message from his friend Rectina wife of Tascius who was living near the foot of the volcano. They were on the other side of the bay and in desperate need of assistance, as their only chance for evacuation was by sea. He set off across the bay and encountered thick showers of hot cinders, lumps of pumice, and pieces of rock. His helmsman advised him to turn back, to which he responded "Fortune favors the brave" and ordered him to continue towards the town of Stabiae, 4.

When they arrived, they saw flames coming from the crater. After staying overnight, they were driven from the building after an accumulation of tephra threatened to block all escape. They woke Pliny and took to the fields with pillows strapped to their heads to protect them from raining debris.

When they approached the beach again, the wind was preventing the ships from leaving. Pliny the Elder lay on a sail that had been put out for him, from which he could not rise, even with assistance. His friends managed to make it out alive, though Pliny the Elder died. His body was found the next day with no apparent injuries. In Pliny the Younger's letter to Tacitus, he suggested that his uncle died after inhaling too much toxic gas.

However, this seems unlikely considering that no one else in the party was affected. It is more likely that he died of a stroke or a heart attack. The total number of casualties is unknown.

By , 1, casts made from impressions of bodies have been found around Pompeii, with another found at Herculaneum. Around thirty-eight percent of the bodies found in Pompeii were inside buildings and most likely died when the roofs collapsed.

The remaining sixty-two percent were found in pyroclastic surge deposits and died due to suffocation from ash and from debris that fell on them. Thanks to the direction of the wind, Herculaneum, which was much closer to the crater, was saved from the tephra falls.

Instead, it was buried under 23 meters 75 ft of material from pyroclastic surges. It is estimated that all the victims from Herculaneum died as a result of these surges. Vesuvius has erupted about three dozen times since 79 AD. In , it released such a large amount of ash that ashfalls were reported as far away as Constantinople 1, km, mi.

Further eruptions recorded the first known lava flows from the volcano. It became quiet however at the end of the 13th century, in which time gardens and vineyards began to cover it. Then, in December of , Vesuvius erupted violently once again. This eruption buried many surrounding villages in lava flows, resulting in the deaths of about 3, people. From then on, eruptions have occurred regularly.

Vesuvius has erupted several times in the 20th century, with the first happening on the 5th of April, This eruption killed more than people and ejected the most lava ever recorded from a Vesuvian eruption. At the time, Italy was preparing to host the Summer Olympics, but after the eruption caused devastating damage to the city of Naples and other surrounding comunes, funds were diverted to reconstructing the city and a new venue was found.

Since , seven of Vesuvuis' eruptions have lasted longer than five years, more than any other volcano except Etna. The two most recent eruptions, and , both lasted longer than thirty years. Vesuvius erupted again in and remained active until For many years, lava could be seen filling the crater, spilling out the side on some occasions.

This period of continuous eruption ended with a major eruption in March of , which destroyed the villages of San Sebastiano al Vesuvio, Massa di Somma, Ottaviano, and parts of San Giorgio a Cremano. The destruction was mostly due to lava flows, but then on the 24th of March, an explosive eruption resulted in a small pyroclastic flow. The hot ash and tephra from the eruption destroyed between 78 and 88 aircraft. The eruption in 79 AD that destroyed the cities of Pompeii and Herculaneum is the most recent large Vesuvian eruption.

The size of the eruption is based on how much volcanic material is released. A large eruption occurs when quantities of about 1 cubic kilometer of volcanic material are released. Scientists estimate that these eruptions occur once every few thousand years, while the medium-sized, sub-Plinian eruptions in which about 0. Smaller eruptions occurred frequently from to , in which only a small amount of volcanic material, about 0.

In the event of an eruption, the government's emergency plan assumes that the worst-case scenario would be an eruption with similar power to the one in , which was measured to have a VEI of 4. The area around the volcano is now densely populated, and estimates suggest that anyone within a 7 kilometer of the vent could be exposed to pyroclastic surges, with other surrounding areas being vulnerable to tephra falls.

The prevailing winds that sweep through the Bay of Naples put the towns and cities to the south and east of the volcano at the highest risk.

For the city of Naples to the northwest, the risk of tephra falls is much lower and experts don't think it would spread past the slopes of the volcano.

The evacuation plan that the government has in place assumes that they will have between two weeks to twenty days to react to an impending eruption. In the event of an evacuation, some , people living in the zona rossa Vesuvius red zone would be evacuated.

The red zone comprises 25 comunes and part of the city of Naples. The evacuation is planned to take about seven days and would involve many evacuees being sent to other parts of the country where they could remain for months. The dilemma that the authorities face, however, is when to start the evacuation process. If they start it too late, thousands could be killed, but if they start too early and the eruption ends up being a false alarm, then it could have repercussions as well.

The last evacuation turned out to be just that when in , 40, people were evacuated from the Campi Flegrei area, but no eruption ever occurred. Italian authorities, especially in Campania, are implementing ongoing efforts to try and reduce the population in the red zone.

This involves demolishing illegally constructed apartment buildings, establishing a national park around the volcano to prevent any further structures from being built, as well as offering people significant financial incentives for moving away.

The overall goal is to reduce the amount of time needed to evacuate the population. At any rate no one here, civilian or Army authorities, seems too much worried. Lava has not started to flow down this side of the mountain as yet but is flowing on the other side toward Naples. But their luck would soon change — something for which the unit was known. But it was also exacerbated by its encounter with Vesuvius. Vesuvius has a long eruptive history and, being just 12 kilometers from downtown Naples, threatens a large population.

The first on this side. Soon many swift, fiery streams were flowing in all directions. The rumbling continues — more prolonged now. This evening it would seem that the whole top of the mountain is burning. Fiery patches here and there resemble a log which is just burning out. Heavy explosions occur followed by prolonged rumbling while sparks and molten lava are thrown high into the air to fall like rain on all sides of the cone.

In the intervening eight days, the crews had been evacuated to a nearby airfield where they spent a frigid night in a tobacco shed, leaving their airplanes behind. The damage to the bombers, some of which were ultimately repaired and returned to service, was not reported in the U.

Germany, however, was aware of the losses earlier. While Vesuvius claimed no military fatalities during the eruption, 26 Italian civilians were killed and nearly 12, were displaced. Most died near Salerno, where heavy ashfall collapsed roofs. Falling volcanic rock killed three in Terzigno. And in San Sebastiano, hot ash boiled a water tank, which exploded, killing two children. But volcanologists no longer need to crawl to the edge of a lava stream in order to monitor the volcano; they have at their disposal a wide variety of remote sensors that measure seismic activity, ground deformation, gravimetric and magnetic field variations, soil and groundwater temperatures, and the composition of gases emitted from fumaroles.

Such continuous monitoring, it is hoped, will make it possible for researchers to provide a short-term forecast that would allow at least two weeks' notice of an impending eruption — the time required to evacuate the nearly , people living within a kilometer radius who are considered most at risk.

All rights reserved. Any copying, redistribution or retransmission of any of the contents of this service without the expressed written permission of the American Geosciences Institute is expressly prohibited. And you would be right! Sadly the mountain sent tremors into the city so often that the people of Pompeii grew used to them, thinking them nothing more than that — tremors. Little did they know the eruption that would eventually follow.

Vesuvius then erupted days later, causing a loud clatter of thunder sound, and blasted a huge cloud of volcanic smoke around 19 kilometres high. After this, large pyroclastic waves of gas, ash, and rock speed down towards Pompeii at speeds of kilometres per hour. This was the main stage that killed the citizens, as those consumed in this wave were burnt alive with temperatures gathered up to degrees Celsius.

The entire eruption time lasted a full 24 hours, where it slowly buried the city in the thick layer of ash and rock. It was a bad time for an eruption, with the locals already suffering dictatorial rule, invasion, and bombings. At the time of the eruption, the United States Army Air Forces th Bombardment Group was based at Pompeii, only a few kilometres from the base of the volcano.

Although no military fatalities occurred, 26 Italian civilians were killed and nearly 12, were displaced. Scientists have estimated its time period between eruptions and have gathered it is due for another eruption soon. However, due to modern technology, monitoring the volcano and its activity is much easier.