Alternative History
Naples volcano

Naples Supervolcano

VEI (volcanic explosivety index) scale runs from:

  1. - Hawaiian volcanic eruption
  2. - Mount Hood/Mount Usu type eruption
  3. - Mount Etna type eruption
  4. - Mount Spurr type eruption
  5. - Mount Saint Helens-type eruption
  6. - Mount Pinatubo type eruption
  7. - Mount Tambora/Krakatoa type eruption
  8. - Yellowstone/Mount Toba type eruption.

History of vulcanism in the Napoli region. Three geological phases or periods are recognised and distinguished.

The First Phlegraean Period. It is thought that the eruption of the Archiflegreo volcano occurred about 37,000 years ago, erupting about 200 cu km (48 cu mi) of magma to produce the Campanian Ignimbrite. (a VEI 7 eruption)

The Second Phlegraean Period. Between the 35,000-10,500 years ago, it is characterized by the yellow tuff that constitutes the rests of an immense underwater volcano (having a diameter of approx 15 km (9.3 mi) Approximately 12,000 years ago the last major eruption occurred, forming a smaller caldera inside the main one, centered on the town of Pozzuoli. This event produced the Neopolitan yellow tuff, referring to the characteristic yellow rocks there.

The Third Phlegraean Period. Dated between 8,000 - 500 years ago, it is characterized by white pozzolana, the material that forms the majority of volcanoes in Flegrei Fields. Broadly speaking, it can be said there was an initial activity to the south-west in the zone of Bacoli and Baiae (10,000-8000 years ago); an intermediate activity in an area centered between Pozzuoli, Spaccata Mountain and Agnano (8000-3900 years ago); and a more recent activity, moved towards the west to form Lake Avernus and Monte Nuovo (New Mountain) (3800-500 years ago). includes eruption of Mount Vesuvius 79 AD eruption (VEI 5)


In late 1943 there are hundreds of earthquakes in the Napoli (Greater Naples region) region. From 6 January to 23 February 1944, lava flows appeared within the rim of Mount Vesuvius and there were outflows. The activity paused on 23 February and resumed on 13 March. Small explosions then occurred until the major explosion took place on 18 March 1944. The eruption could be seen from the centre of Naples. ,everal million tonnes of ash are ejected into the Napoli region.

The local population begins moving away from the falling ash, many traveling by train to the Italian capital, Rome.

The earthquakes begin to build, by the 20th March 1944 the earthquakes are now constant at 3.5-4 in the Richter scale with daily ones above 5.5.

23rd March 1944

2:21am - An eruption begins in the Flegrei fields, Monte Nouvo and Gauro craters begin issuing steam and ash.

2:20am - 50 m south of Isola di Nisidia a large vent opens on the sea floor, the hydrothermal explosion sets a 2m Tsunami across the Bay of Naples and washes on the western shore.

2:24am - The vent south of Isola di Nisidia expands the nearly 100m across, the island begins to break up and collapse into the newly forming crater.

2:28am - Four vents open under the bay of Naples near the island of Capri.

between 3am and 3.25am eruptions at all vents slowly increases from a VEI 3 to VEI 5 type eruption

3:31am - Mount Vesuvius erupts in a Plinian (VEI 5) eruption on the same scale as the eruption in 79 AD (the one that destroyed Pompeii and Herculanium)

3:35am - The entire Flegrean fields erupts in massive explosion. (VEI 7)

3:41am - A massive VEI 8 (supervolcanic) eruption begins centered under the northern end of the bay of Naples. The cauldera rim is approximately nine miles north to south and 12 miles west to east.

By the 26th March 1944 2,500 cu mi of ash has been erupted by the new Napoli supervolcano, the prevailing wind is to the north-north east, Italy is buried under 6-8 feet of ash, ashfall is one to three feet deep in Yugoslavia, Austria and Germany, six inches deep in the UK, France, and Scandinavia and the Soviet Union has between three inches (in Moscow) and one inch.

The Second World War grinds to a halt, radios are unusable as the amount of ash in the air causes massive static, all air travel stops as the ash in the air blocks the engine intakes. Millions die in Italy and mainland Europe due to inhaling the ash, which forms a substance similar to wet cement.

The summer of 1944 is the coldest on record with frosts in July and August, crops failed across the continent, livestock suffer fluoridosis from eating the ash covered grass and die in their millions.

By October 1944 the German Third Reich calls for peace with the USSR and the UK, both of which are also suffering from starvation due to destroyed winter crops and the inability to plant new crops due to the depth of ash.

20th October 1944 - Peace in Europe is declared,(with no victors) Europe is divided amongst USSR, Germany and the UK, the border between USSR and Germany stays the same as of Jan 1st 1939, the UK declares that the areas given to them to be returned the their people (this includes all of France, and most of the Netherlands and Belgium) Germany takes Italy (as the government has collapsed and Mussolini has committed suicide)the USA withdraws all troops from Europe to focus on the Pacific war. The UK declares peace with Japan.

19th December 1944 due to the increased troops and the lack of air support the USA invades the Japanese mainland, landing in four locations

  1. Kashiwazaki in the north coast of Honshu
  2. Numanzu on the south coast of Honshu- west of Tokyo
  3. Iwaki - east of Tokyo
  4. Kamogawa - south of Tokyo.

a total of 250,000 men land, resistance is minimal due to the famine caused by the decreasing temperatures in the volcanic winter.

3rd January 1945, US troops reach the outskirts of Tokyo, as mortars begin to fall in the imperial palace. Emperor Hirohito, against military advice, contacts the US forces to ask for a unconditional surrender.

21st January 1945, the USS Missouri sails into Tokyo bay flanked by one Japanese destroyer and one Soviet destroyer. On the deck of the USS Missouri Emperor Hirohito, President Franklin D. Roosevelt and Joseph Stalin sign the peace accords. Japan retains the control of the main home islands of Japan plus the Ryukyu Islands (including Okinawa)

By mid March 1945 it is noticed that the weather does not seem to be getting any warmer, temperature as on average two degrees cooler than 1943.

1945 is later referred to as the great winter. Snow falls in the northern hemisphere throughout the whole summer as far south as Spain, Egypt and Florida. hail storms in the mid-west USA destroy the majority of the maize and wheat crops.