Now we come to the most destructive part about volcanoes. Actual eruptions and the disasters they cause. Below are some of the most terrible and deadliest eruptions of all history.

Kelut, Indonesia-1586: Lahars sweep down the slopes of Kelut, destroying villages and killing 10,000 people.

Vesuvius-79ad,1631: Vesuvius' best known eruption occurred 79ad. The volcano had remained dormant for several hundred years and so was considered to be extinct. The crater was overgrown with vegetation and except for a few earthquakes that occurred 16 years before, there was no warning. The eruption buried the cities of Herculaneum and Pompeii. The eruption lasted several days, but it only took two pyroclastic flows to wipe out the twin cities. Twelve hours after the eruption began, several thousand people were buried. In 1631 as many as 6,000 people died in another large eruption. Since then Vesuvius has continued to erupt intermittently to this day.

Nevado del Ruiz-1985: November 13, 1985 was a stormy night at Nevado del Ruiz. A seismic station 9 kilometers away was monitoring the volcano and sending updates to the Colombian emergency response coordinators. Unfortunately for the people of the area, the storm obscured the eruption and only an earthquake was registered. The eruption sent pyroclastic flows that immediately melted the glaciers on it. As a result, lahars as much as 40 meters thick and travelling at 50 km/hr rushed through the river valleys undetected. Two and a half hours after the eruption, the lahars swept over the town of Armero. 23,000 people died.

Mont Pelee-1902: It was a rather average day in Martinique. The day seemed to pass without incident, but things would change dramatically before the day was over. Within a few hours Mont Pelee erupted and sent a pyroclastic flow screaming toward St. Pierre at a devastating speed of at least 160 km/hr. The entire city was destroyed leaving only two survivors. One miraculously made his way through the burning city. The other had been locked away in a steel, dungeon-like jail cell with no ventilation. I doubt anyone had ever been more glad to be in jail. 30,000 people were killed during that and the subsequent days.

Raung, Indonesia-1638: A lahar tears through the country side killing 1,000 people.

Merapi, Indonesia-1672: a pyroclastic flow rips through the valleys and low lands of the surrounding area of Merapi. As many as 3,000 people were reported dead.

Awu, Sulawesi, Indonesia-1711,1856, 1892: In 1711, another pyroclastic flow terrorizes the country leaving an estimated 3000 dead. 1856: Awu strikes again, this time bringing down a lahar to kill another 3,000 people. 36 years later Awu erupts again, killing 1,532 people in pyroclastic flows and lahars. Tradition and farming are usually the reasons people continue returning to such dangerous locations

Oshima, Japan-1741: The island of Oshima erupts unexpectedly and causes a tsunami to sweep across coastal areas of Japan. 1,481 people are killed.

Makian, Indonesia-1760: around 2,000 people are destroyed in a lahar that wiped out surrounding areas.

Papadanyan, Indonesia-1772: 2,960 people are buried and killed when a volcanic eruption triggers a landslide on the flank of the volcano.

Gamala, Indonesia-1775: once again, people are buried in Indonesia, this time by a pyroclastic flow. Death toll is estimated at 1,300.

Lakagigar, Iceland-1783: In 1783, the Lakagigar Fissure begins erupting on June 8. The eruptions exhibit a phreatomagmatic style, but, as water sources become exhausted eruptions become strombolian, and, as the intensity increased it moved on to hawaiian. The fissure produced lava fountains that reached heights of 1,400 meters and discharged 8,600 cubic meters every second! The fissures along which the eruptions occurred were spread out over 2.5 kilometers. The lava immediately began pouring into the lowlands and within four days traveled 35 kilometers from the vents. The lava continued to pour forth from the vents until February 7, 1784-8 months later! Laki was directly responsible for few deaths; however, it was certainly a killer. Laki released huge amounts of aerosols into the air that rose kilometers into the atmosphere. The deaths Laki caused were from starvation. A major contaminant produced by Laki was fluorine which is readily absorbed by plants. The livestock ate the now toxic plants and died. Crops also failed because of the amount and high ph of acid rain that fell on the island. The aerosols caused temperatures in North America to drop by as much as 1 degree celsius, but more pertinent is the fact that, due to the aerosols, 9,000 people in Iceland died-one quarter of the country's population.

Asama, Japan-1783: Asama, located near a village in Japan, erupted, sending pyroclastic flows and lahars careening down its slopes. An estimated 466 people died from the pyroclastic flow and 1,400 from the lahar.

Unzen, Japan-1792: once again, Japan is rocked by another volcanic eruption. This one kills no one directly, but causes a tsunami to wash over coastal areas and kill roughly 15,000 people.

Mayon, Philippines-1814: Mayon erupts, taking 1,200 lives in pyroclastic flows.

Tambora, Indonesia-1815: The greatest volcanic disaster in all of recorded history. Tambora, located on the island of Sumbawa, Indonesia gave about 3 years of warning prior to it's eruption in the form of small phreatic eruptions and steaming. On April 5, 1815, a large explosion rocked the area. "Thunder-like" sounds were heard as far as 1,400 km away. The mayor of Java sent out rescue parties when he "heard the sound of cannons" over the water and thought there was a ship in distress. A captain for the East India Company also sent out search parties when he heard "a great artillery with intermittent riflery in between." A still larger eruption shook the area April 10-11, raising the amount of material ejected to 50 cubic km. The eruption killed 12,000 people people due to pyroclastic flows, but that was not the main killer. The aerosols released into the air by Tambora caused a global climate change that rocked the world. It dropped global temperatures as much as 3 degrees celsius and is responsible for "the year without a summer". During 1816, temperatures often dropped below freezing in the middle of June during the day, and farmers were plagued by ice storms during their planting season. Least impacted was Georgia and Florida who would have warm spells that would last just long enough for farmers to plant more crops before killing them. This caused a world-wide famine that resulted in the death of an additional 80,000 people. This brought the Tambora death toll to a staggering 92,000 lives.

Galunggung, Indonesia-1822: the land plagued by fiery earth is struck once again. 4,000 lives are taken in a lahar.

Krakatau, Indonesia-1883: Like Tambora, Krakatau exhibited several years of seismicity before its eruption. The final eruption blew away the top three quarters of the island and the explosion was heard 4,500 km away, making it the loudest noise in history. The eruption killed 5,000 people in pyroclastic flows and killed an additional 31,417 people in tsunamis.

Ritter, Papua New Guinea-1888: Ritter erupts, producing a landslide that creates a tsunami. 3,000 people die as a result.

Soufriere, St. Vincent-1902: A pyroclastic flow kills 1532 people.

Taal, Philippines-1911: 1,335 people die in another pyroclastic flow.

Lamington, Papua New Guinea-1951: 2,942 people perish when pyroclastic flows overtake them.

Agung, Indonesia-1963: as many as 1500 people die as a result of lahars and pyroclastic flows.

El Chichon, Mexico-1982: more than 2,000 people perish when pyroclastic flows sweep down on them.

Now we come to the last and perhaps most bizarre volcanic disaster in history. Lake Nyos, Cameroon-1986: On august 12, 1986, Lake Nyos killed 1700 people. Lake Nyos never erupted lava or ash. The victims were asphyxiated. Beneath the innocent waters of Lake Nyos, lies a large source of magma. As the magma degasses, the gas is dissolved into the bottom of the lake. Triggered by a landslide, the eruption was probably similar to what happens when you shake a bottle of soda. The silent, deadly gas rolled down the slopes and settled in low lying areas, in one of which lay a local village. The inhabitants found their oxygen supply suddenly cut off and were asphyxiated.

These are the greatest, or perhaps the worst, volcanic disasters of recorded history. Now we switch to a story which changes the topic from killer volcanoes to volcano killers.

Eldfell, Heimaey, Iceland-1973: Never in all of history was such a heroic effort put forth to save a community from the grip of a killer volcano. Eldfell fissure, of Heimaey, Iceland, began to erupt in 1973. The eruption was located near a city and the nation's most important fishing port. Rather than roll over and let their economy die, the Icelanders decided to fight the volcano and save their port. Armed with fire hoses, the men advanced toward the lava flows that were making their way through the city. They began pouring water on the advancing flows and began stopping them! The eruption lasted seven months and the firemen used 8 million cubic yards of seawater, but the effort worked. The majority of the town was saved along with the fishing port and Iceland's economy.