volcanic eruptions The 11 Biggest Volcanic Eruptions in History

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History has seen some monstrous eruptions of volcanoes, from Mount Pinatubo's weather-cooling burp to the explosion of Mt. Tambora, one of the tallest peaks in the Indonesian archipelago.

 

The power of such eruptions is measured using the Volcanic Explosivity Index (VEI) a classification system developed in the 1980 that's somewhat akin to the magnitude scale for earthquakes. The scale goes from 1 to 8, and each succeeding VEI is 10 times greater than the last.

 

There haven't been any VEI-8 volcanoes in the last 10,000 years, but human history has seen some powerful and devastating eruptions. Because it's extremely difficult for scientists to be able to rank the strength of eruptions in the same VEI category, here we present the 10 most powerful volcanoes within the last 4,000 years (within human records) first in order of strength, then within each category, in chronological order. But let's start with a supervolcano eruption, registering a magnitude-8, from our distant past…

 

On this anniversary, we countdown the largest volcanic eruptions in history as measured by the Volcanic Explosivity Index (VEI) a classification system somewhat akin to the magnitude scale for earthquakes.

 

The system was developed in the 1980s, and uses factors such as the volume of an eruption, its rate, and other variables to quantify a volcano's power. The scale goes from 1 to 8, and each succeeding VEI is 10 times greater than the last.

 

There haven't been any VEI-8 volcanoes in the last 10,000 years, but human history has seen some powerful and devastating eruptions. Because it's extremely difficult for scientists to be able to rank the strength of eruptions in the same VEI category, here we present the 10 most powerful volcanoes within the last 4,000 years (within human records) first in order of strength, then within each category, in chronological order.

 

Yellowstone, 640K years ago (VEI 8)

 

 

The entire Yellowstone National Park is an active volcano rumbling beneath visitors' feet. And it has erupted with magnificent strength: Three magnitude-8 eruptions rocked the area as far back as 2.1 million years ago, again 1.2 million years ago and most recently 640,000 years ago. "Together, the three catastrophic eruptions expelled enough ash and lava to fill the Grand Canyon," according to the U.S. Geological Survey. In fact, scientists discovered a humongous blob of magma stored beneath Yellowstone, a blob that if released could fill the Grand Canyon 11 times over, the researchers reported on April 23, 2013, in the journal Science.

 

The latest of the trio of supervolcano eruptions created the park's huge crater, measuring 30 by 45 miles across (48 by 72 kilometers).

 

The chance of such a supervolcano eruption happening today is about one in 700,000 every year, Robert Smith, a seismologist at the University of Utah in Salt Lake City, told Live Science previously.

 

Huaynaputina, 1600 (VEI 6)

 

 

This peak was the site of South America's largest volcanic eruption in recorded history. The explosion sent mudflows as far as the Pacific Ocean, 75 miles (120 km) away, and appears to have affected the global climate. The summers following the 1600 eruption were some of the coldest in 500 years. Ash from the explosion buried a 20-square-mile (50-square-km) area to the mountain's west, which remains blanketed to this day.

 

Although Huaynaputina, in Peru, is a lofty 16,000 feet (4,850 meters), it's somewhat sneaky as volcanoes go. It stands along the edge of a deep canyon, and its peak doesn't have the dramatic silhouette often associated with volcanoes.

 

The 1600 cataclysm damaged the nearby cities of Arequipa and Moquengua, which only fully recovered more than a century later.

 

Krakatoa, 1883 (VEI 6)

 

 

The rumblings that preceded the final eruption of Krakatoa (also spelled Krakatau) in the weeks and months of the summer of 1883 finally climaxed with a massive explosion on April 26-27. The explosive eruption of this stratovolcano, situated along a volcanic island arc at the subduction zone of the Indo-Australian plate, ejected huge amounts of rock, ash and pumice and was heard thousands of miles away.

 

The explosion also created a tsunami, whose maximum wave heights reached 140 feet (40 meters) and killed about 34,000 people. Tidal gauges more than 7,000 miles (11,000 km) away on the Arabian Peninsula even registered the increase in wave heights.

 

While the island that once hosted Krakatoa was completely destroyed in the eruption, new eruptions beginning in December 1927 built the Anak Krakatau ("Child of Krakatau") cone in the center of the caldera produced by the 1883 eruption. Anak Krakatau sporadically comes to life, building a new island in the shadow of its parent.

 

Santa Maria Volcano, 1902 (VEI 6)

 

The Santa Maria eruption in 1902 was one of the largest eruptions of the 20th century. The violent explosion in Guatemala came after the volcano had remained silent for roughly 500 years, and left a large crater, nearly a mile (1.5 km) across, on the mountain's southwest flank.

 

The symmetrical, tree-covered volcano is part of a chain of stratovolcanoes that rises along Guatemala's Pacific coastal plain. It has experienced continuous activity since its last blast, a VEI 3, which occurred in 1922. In 1929, Santa Maria spewed forth a a pyroclastic flow (a fast-moving wall of scalding gas and pulverized rock), which claimed hundreds of lives and may have killed as many as 5,000 people.

 

Novarupta, 1912 (VEI 6)

 

 

The eruption of Novarupta one of a chain of volcanoes on the Alaska Peninsula, part of the Pacific Ring of Fire was the largest volcanic blast of the 20th century. The powerful eruption sent 3 cubic miles (12.5 cubic km) of magma and ash into the air, which fell to cover an area of 3,000 square miles (7,800 square km) in ash more than a foot deep.

 

Mount Pinatubo, 1991 (VEI 6)

 

 

A stratovolcano located in a chain of volcanoes in Luzon, Philippines, created along a subduction zone, the cataclysmic eruption of Pinatubo was a classic explosive eruption.

 

The eruption ejected more than 1 cubic mile (5 cubic kilometers) of material into the air and created a column of ash that rose up 22 miles (35 km) in the atmosphere. Ash fell across the countryside, even piling up so much that some roofs collapsed under the weight.

 

The blast also spewed millions of tons of sulfur dioxide and other particles into the air, which were spread around the world by air currents and caused global temperatures to drop by about 1 degree Fahrenheit (0.5 degree Celsius) over the course of the following year.

 

Ambrym Island, 50 AD (VEI 6 +)

 

 

The 257-square-mile (665-square-km) volcanic island, part of the Republic of Vanuatu, a tiny nation in the southwestern Pacific Ocean, witnessed one of the most impressive eruptions in history, one that sent a wave of scalding ash and dust down the mountain and formed a caldera 7.5 miles (12 km) wide.

 

The volcano has continued to be one of the most active in the world. It has erupted close to 50 times since 1774, and has proved a dangerous neighbor for the local population. In 1894, six people were killed by volcanic bombs and four people were overtaken by lava flows, and in 1979, acid rainfall caused by the volcano burned some inhabitants.

 

Ilopango Volcano, 450 AD (VEI 6 +)

 

 

Although this mountain in central El Salvador, just a few miles east of the capital city San Salvador, has only experienced two eruptions in its history, the first known eruption was a doozy. It blanketed much of central and western El Salvador with pumice and ash, and destroyed early Mayan cities, forcing inhabitants to flee.

 

Trade routes were disrupted, and the centers of Mayan civilization shifted from the highland areas of El Salvador to lowland areas to the north and in Guatemala.

 

The summit's caldera is now home to one of El Salvador's largest lakes.

 

Mt. Thera, approx. 1610 B.C. (VEI 7)

 

 

Geologists think that the Aegean Islands volcano Thera explodedwith the energy of several hundred atomic bombs in a fraction of a second. Though there are no written records of the eruption, geologists think it could be the strongest explosion ever witnessed.

 

The island that hosted the volcano, Santorini (part of an archipelago of volcanic islands in Greece), had been home to members of the Minoan civilization, though there are some indications that the inhabitants of the island suspected the volcano was going to blow its top and evacuated. But though those residents might have escaped, there is cause to speculate that the volcano severely disrupted the culture, with tsunamis and temperature declines caused by the massive amounts of sulfur dioxide it spewed into the atmosphere that altered the climate.

 

Changbaishan Volcano, 1000 AD (VEI 7)

 

 

Also known as the Baitoushan Volcano, the eruption spewed volcanic material as far away as northern Japan, a distance of approximately 750 miles (1,200 kilometers). The eruption also created a large caldera nearly 3 miles (4.5 km) across and a half-mile (nearly 1 km) deep at the mountain's summit. It is now filled with the waters of Lake Tianchi, or Sky Lake, a popular tourist destination both for its natural beauty and alleged sightings of unidentified creatures living in its depths.

 

Located on the border of China and North Korea, the mountain last erupted in 1702, and geologists consider it to be dormant. Gas emissions were reported from the summit and nearby hot springs in 1994, but no evidence of renewed activity of the volcano was observed.

 

Mt. Tambora, Sumbawa Island, Indonesia - 1815 VEI 7

 

 

The explosion of Mount Tambora is the largest ever recorded by humans, ranking a 7 (or "super-colossal") on the Volcanic Explosivity Index, the second-highest rating in the index. The volcano, which is still active, is one of the tallest peaks in the Indonesian archipelago.

 

The eruption reached its peak in April 1815, when it exploded so loudly that it was heard on Sumatra Island, more than 1,200 miles (1,930 km) away. The death toll from the eruption was estimated at 71,000 people, and clouds of heavy ash descended on many far-away islands.

http://www.livescience.com/30507-volcanoes-biggest-history.html

 

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And history, even geologic history, repeats... 

 

Keep an Eye Out for These Volcanoes in 2016

 

AS WE ENTER the new year, I tend to get a lot of questions about what volcanoes might be the ones to watch in the coming year. Answering is a difficult task, because volcanic unrest can spring up quickly. Trying to prognosticate about which volcanoes might erupt is about as predictable as who will make this year’s baseball playoffs. Sure, you can make some fairly sure bets, but you never know when the next dark horse will emerge.

 

So I thought I’d try to give you some of my thoughts on volcanic activity in 2016. By no means are these predictions. As of now, there is no reliable, tested way to predict volcanic eruptions precisely anywhere beyond a few hours to maybe days in advance (and don’t believe otherwise). However, there are some places to watch and things to ponder as the months roll by.

 

Without further ado (and in no particular order), a volcanic preview for 2016:

 

Cotopaxi, Ecuador: There was a lot of rumbling and even a brief eruption at Ecuador’s Cotopaxi in 2015, but nothing much beyond that. Now, I do wonder if the 2015 activity was just a prelude to something more—whether it be a larger eruption or merely more sustained and prolonged activity.

 

The last major eruption from Cotopaxi was a VEI 3 back in 1903 and you have to go back to 1877 for something larger than that. However, up until the 1940s, the last few hundred years at Cotopaxi was littered with eruptions. So, any restlessness makes me wonder if we’re headed back into a long stretch of eruptions. Right now, the volcano has settled down and the government has lifted the state of emergency, but you can watch the webcams for any changes.

 

Mauna Loa and Kilauea, Hawaii: Kilauea is nothing if not consistent. 2016 marks 33 years of eruption at the Hawaiian volcano. You have to wonder how long can Kilauea keep this up (hint: probably much longer than 33 years). However, over the past year, Mauna Loa has also begun to show signs of restlessness and there are some indications (though they’re still not proven) that Kilauea and Mauna Loa trade off eruptions. Even beyond the idea that a Mauna Loa eruption could end Kilauea’s run, new lava flows from Mauna Loa have the potential to be hazardous for the city of Hilo.

 

Etna, Italy: I just have this feeling that the exciting, explosive eruptions in December from Etna were only a prelude to an active year at the Italian volcano. There are no fewer than four craters on the volcano that have taken part in eruptions over the past year, so it is anybody’s guess how new active series of paroxysms would unfold. If ever there was a safe bet for a volcanically-active year, it is Etna. It never hurts to keep an eye on those webcams.

 

Nevados de Chillán, Chile (above): As the new year started, the SERNAGEOMIN in Chile raised the alert status at Nevados de Chillán to yellow after a few months of increasing unrest in the form of small earthquakes and increased steam and volcanic gas emissions. Nevados de Chillán is one of the more active volcanoes in Chile, but it has now been over 15 years since its last eruptive period, so it wouldn’t be out of the question to see renewed activity.

 

Cascades, United States: Now that it’s 2016, we can officially say that the only Cascade Range volcano to erupt in the past century is Mount St. Helens. With 13 potentially active volcanoes from California to Canada, this seems like an awfully quiet period (and I’ve tackled some reasons why this might be). More likely than not, 2016 will pass without any activity from the Cascades and even if an eruption were to happen, it would probably be from Mount St. Helens, but we should keep a watchful eye on the others to see if the range awakens from its slumber.

 

Wild Cards: When it comes down to it, many of the big eruptions of the past few decades have come from volcanoes that no one would have guessed: Pinatubo, El Chichón, Chaitén, Eyjafallajökull, and Sarychev Peak, to name a few. If a significant eruption comes in 2016, my bet is that it would be from a volcano that many haven’t even considered. That’s what can make volcano monitoring so treacherous (and exciting): You never know when a volcano that hasn’t erupted for thousands of years will make itself known again.

 

So, in 2016, keep your eyes open for new rumblings. If you have any hunches of your own, leave them in the comments so we can look back when 2017 arrives to see if we had any luck in guessing where the action was this year.

 

(P.S. One volcano that has nearly zero chance of an eruption in 2016? Yellowstone. Take that to the bank.)

 

http://www.wired.com/2016/01/keep-an-eye-out-for-these-volcanoes-in-2016/

 

[AP1972]

June 7, 2011 woke beautiful volcano Puyehue who slept for more than 50 years.

The volcano is part of the mountain range Kauye Cordon , located in the Andes , 800 km south of the Chilean capital Santiago.

Meteorologists say that the cloud of dust over the Puyehue rose to an altitude of 10 km.