Volcanic mountains

The biggest volcanic eruptions of all time

For hard evidence of nature’s ability to degenerate into catastrophic disaster, look no further than the volcano. These metaphorical portals to hell, which currently number around 1,500 worldwide, not only spew volcanic ash and lava, but can dramatically alter the climate and course of world events.

Most are stratovolcanoes, cone-shaped elevations built over time from layers of ash and lava. Their relatively soft composition allows pressure to build up inside until they explode, causing explosive eruptions with little prior warning. Their steep slopes also generate mudslides and pyroclastic flows. All of these factors make it the most dangerous type of volcano. (In contrast, shield volcanoes, like those in Hawaii, are close to the ground and often emit syrupy lava from Earth’s vents.)

Need examples? Look no further than these incendiary volcanic milestones, in no particular order.

1. Novarupta // Alaska

Volcanic eruptions can be measured in terms of consequences or simply in terms of pure production. In the latter’s case, the eruption of Novarupta, or Katmai, which began on June 6, 1912, was a monumental event. More than 13 cubic kilometers of lava were released in 60 hours, equivalent to 573.2 million tonnes per hour. At Kodiak, about 100 miles away, more than one foot of ash was picked up from the ground. The sheet of cooled ash surrounding the volcano ended up forming the “Valley of 10,000 fumes”, creating smoking fumaroles (openings in the ground where gas or water vapor escape). The incident even caused an atmospheric haze that would have reduced summer temperatures. In total, this was the largest volcanic eruption of the 20th century and scored a 6 on the Volcanic Explosive Index (VEI), a measure of the explosive thrust of an eruption, with 1 being the least powerful and 8 most powerful.

2. Krakatoa // Indonesia

Indonesia holds the unwelcome distinction of hosting two of the most powerful volcanic events of the 1800s. (Unfortunate, but understandable – its 150 active volcanoes are the most of any country.) One occurred in August 1883, when Krakatoa (sometimes spelled Krakatau) erupted on an island near Sumatra. About five cubic miles of lava were blown 50 miles into the air and triggered massive tsunamis. The volcano issued several warnings in the months leading up to its big explosion, with a series of relatively smaller explosions where the ash plume reached alone seven miles in the sky. The first large explosion, with an VEI of 6, occurred on August 26, which demolished two-thirds of the island. Multiple eruptions followed, causing a worldwide veil of ash that ultimately caused the planet’s temperature to drop by several degrees. About 36,000 people were killed, including 31,000 who died when the tsunamis hit neighboring islands.

3. Mount Tambora // Indonesia

The ruthless volcanoes were in full force and morbid with Mount Tambora, which blew in April 1815 in Sumbawa, Indonesia. In the days leading up to the explosion, which had an VEI of 7, soldiers nearby heard a cannon-like roar and armed themselves, believing an enemy was about to attack. In a way, one was. Tambora spat 12 cubic miles of gas and dust 25 miles into the atmosphere, triggering massive tsunamis and flooding surrounding islands with ash. About 10,000 people died immediately and a total of 90,000 died from the resulting food shortages. Today, scientists believe the epic eruption may have drastically altered the global climate, leading to crop failures and famine in North America and Europe. In 1816, with Tambora’s ashes still covering the northern hemisphere skies, the poet Lord Byron challenged his literary friends, including Mary Shelley, to write something macabre in the proper way. She started Frankenstein.

4. Mount St. Helens // Washington

Volcanic terror struck North America on May 18, 1980, when Mount St. Helens exploded. A few days earlier, an earthquake had caused avalanches on the volcano. Thousands of earthquakes followed, which destabilized the land. Then, a magnitude 5.1 earthquake struck, causing ash and hot gases to blow up into the sky. The explosion removed an incredible 1,314 feet from the height of the mountain. The effects were felt and seen over 230 square miles and 158 miles of highway were damaged. Recovery from the disaster cost more than $ 1.1 billion. With 57 people killed, the Mount St. Helens explosion – with an IVE of 5 – remains the deadliest volcanic eruption in U.S. history.

5. Mount Vesuvius // Italy

While not quite on par with other massive eruptions (it’s only a 5 on the Volcanic Explosive Index), the lore surrounding Mount Vesuvius’s rage puts it in a category of its own. . The volcano exploded on August 24, 79 CE, transforming the Roman cities of Pompeii and Herculaneum into frozen portraits of thousands of interrupted lives. Before being covered with ashes, Pompeii was known for its fertile grounds which nourished orchards and vineyards; Herculaneum was a summer getaway for the Roman elite. When Vesuvius erupted, many stayed hoping to wait. But another explosion gassed and incinerated the towns, then buried them in mud and ash. The cities were rediscovered in the 18th century and new discoveries about the last days of Pompeii and Herculaneum are still in progress.

6. Mount Pinatubo // Philippines

A colossal volcanic eruption (6 on the VEI) of a recent vintage, Mount Pinatubo caused the cataclysmic destruction of a densely populated part of Luzon in the Philippines on June 15, 1991. After a series of earthquakes and a flow of As magma making its way 20 miles back to the Earth’s surface, Pinatubo’s activity increased when gas-fueled lava, totaling more than five cubic kilometers, was released. Pyroclastic flows of ash and pumice left deposits over 660 feet thick at the foot of the mountain, while tropical storms created vast mudslides from the volcanic ejecta. Heavy layers of damp ash crushed buildings. Fortunately, scientific forecasts were able to alert the inhabitants, who were evacuated; thousands of lives have been saved.

7. Laki // Iceland

Out of sheer stubbornness, few volcanic eruptions have beaten Laski, located in what is now Vatnajökull National Park in Iceland. Instead of a giant eruption, Laki perpetuated a series of lava flows and explosions that lasted for over eight months in 1783 and 1784 and recorded an VEI of 4. Laki produced enough lava to pave the entire area. Boston city at a depth of 207 feet. The eruption emitted gases that resulted in acid rain strong enough to scorch leaves and irritate the skin, while the toll on livestock caused a famine that may have killed up to a quarter of the Icelandic population. at the time. As in the aftermath of the Tambora eruption, Laki’s ash veil has caused widespread weather disruption and food shortages in Europe. It may even have fueled the unrest that preceded the French Revolution.

8. Montagne Pelée // Martinique

Mount Pelée towered over the peaceful hamlet of Saint-Pierre, on the French Caribbean island of Martinique, like a time bomb. In early May 1902, a violent lahar – a river of fragments of volcanic rocks and water – erupted from the mountainside, inundating a sugar refinery before reaching the sea and triggering a tsunami. The disturbances caused wildlife – huge insects and poisonous snakes – to flee the mountains and seek refuge in the city. The bites of vipers killed around 50 people. But the governor of the island assured residents that there was no real danger. Unfortunately, he was extremely wrong. On May 8, the mountain exploded with an VEI of 4, triggering an explosion of superheated gas and debris that destroyed Saint-Pierre and killed 30,000 residents within minutes.

9. Nevado del Ruiz // Colombia

At 77 square miles, Nevado del Ruiz is an imposing stratovolcano. It has erupted several times since 1570, but the most memorable event occurred on November 13, 1985. As magma bubbled up towards the top of the volcano, heat melted huge glaciers that covered the summit. Rivers of melted ice became devastating lahars, which joined with existing rivers to cause catastrophic mudslides in the valleys. In the eruption of VEI 3, the neighboring town of Armero was leveled and 23,000 people lost their lives in the floods.

10. Mount Tarawera // New Zealand

The people of New Zealand’s North Island suffered seismic shock on June 10, 1886, when Mount Tarawera erupted, forming cracks in the Earth that extended 10 miles from the epicenter. The VEI 5 ​​explosions were heard up to 310 miles away, making it the largest volcanic event in New Zealand history. There are also ghost stories attached to it. Some European residents insisted they saw a Maori war canoe sailing on Lake Tarawera just before the eruption. They hailed the sailors, but they did not respond. Later, after the cataclysm, observers learned that such a canoe had never been seen on the lake.

11. Yellowstone // Wyoming

Under Yellowstone National Park hides a supervolcano, which is believed to have erupted at least three times in human history: 2.1 million years ago (which had an VEI of 8), 1 , 3 million years ago and 664,000 years ago. The latter left a depression in the ground 34 miles by 50 miles. Today, the magma beneath Yellowstone is five miles deep, leading some to speculate that if it erupts – and there’s a non-zero chance that it will – it could bury the Rockies in ash. , thanks to its potential to trigger a super-eruption. (anything that has an VEI of 8 or higher).


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