7:15 AM | *It was this time of year in 79 A.D. that Mount Vesuvius erupted and Pompeii, Italy was changed forever…the important role of the weather…some new discoveries* — Arcfield Weather

The eruption and the important role of the weather

While there was a powerful earthquake in the same region some seventeen years beforehand, in the days preceding the massive eruption on Mount Vesuvius there were generally only minor earthquakes and this was not too unusual for the residents of Pompeii who had no idea what was about to happen. In fact, the people of Pompeii didn’t really even know that Mount Vesuvius was a volcano as it hadn’t erupted in 1800 years. Then, shortly after noon on August 24th in the year 79 A.D., a major eruption sent a plume of ashes, pumice and other rocks, and scorching-hot volcanic gases so high into the sky that people could see it for hundreds of miles around. Ironically, this eruption took place the day after the Roman holiday of Vulcanalia which is dedicated to the god of fire including fire from volcanoes. This outpouring of ash more than 20 miles high into the upper atmosphere continued unabated for the next 12 hours and choking ash rained down on the towns in the surrounding country side blocking doors and collapsing roofs. Had the eruption taken place on any other day, the people of Pompeii might have stood a better chance of escape. Usually the wind blows in a southwesterly direction during the summer season in this part of the Italian Peninsula and this would have blown the column of ash away from Pompeii.  However, on that fateful day, the wind was blowing in a northwesterly direction – straight towards Pompeii.

Detailed eyewitness account

A young writer known as “Pliny the Younger” witnessed the eruption from across the Bay of Naples in a small town about 15 miles from Mount Vesuvius.  In the only known eyewitness account, this writer provided a very detailed account of the eruption in a series of letters discovered in the 16th century.  He compared the ash cloud to a (Mediterranean) pine tree and wrote that the cloud had an “unusual size and appearance” and “rose to a great height on a sort of trunk and then split off into branches”.  As it cooled, the tower of debris drifted to earth: first the fine-grained ash, then the lightweight chunks of pumice and other rocks. It was terrifying–“I believed I was perishing with the world,” Pliny wrote, “and the world with me”.  “You could hear the shrieks of woman, the wailing of infants, and the shouting of men,” he wrote years later to the Roman historian Tacitus. “Some were calling their parents, others their children or their wives, trying to recognize them by their voices.” As Vesuvius buried Herculaneum and Pompeii and Stabiae, across the Gulf of Naples, Pliny the Younger remembered the spreading volcanic darkness. “Not the dark of a moonless or cloudy night, but as if a lamp had been put out in a closed room,” he wrote.  “At last the darkness thinned and dispersed into smoke or cloud,” he told Tacitus. “Then there was genuine daylight, and the sun actually shone out, but yellowish as it is during an eclipse. We were terrified to see everything changed, buried deep in ashes like snowdrifts.”

This young writer’s uncle known as “Pliny the Elder”, an admiral of the Roman fleet and a distinguished author and naturalist, was actually one of the victims while trying to rescue stranded citizens. He sailed to the scene from Misenum to rescue people, but collapsed on the shore and died, apparently from the fumes, his nephew wrote.