Do you know how many active volcanoes there are on our planet? About six hundred. This is relatively little, considering that more than a thousand no longer threaten humanity, since they have cooled down. More than ten thousand volcanoes are hidden under the surface of sea and ocean waters. And yet the danger of a volcanic eruption exists in many countries. There are more than a hundred of them near Indonesia, in the west of America there are about ten, and there are “rumbling mountains” in Japan, Kamchatka and the Kuril Islands. Today we will talk about the most powerful volcanic eruptions that claimed many lives and left a noticeable imprint on the history of civilization. Let's get acquainted with the most dangerous representatives of these formidable mountains. Let's find out whether we should be afraid of the Yellowstone volcano today, which worries scientists around the world. Perhaps we'll start with that.
Yellowstone supervolcano
Today, volcanologists have identified twenty supervolcanoes, compared to which the remaining 580 are nothing. They are located in Japan, New Zealand, California, New Mexico and other places. But the most dangerous of the entire group is the Yellowstone volcano. Today, this monster is causing concern to all scientists, as it is ready to spew tons of lava onto the surface of the earth.
Dimensions of Yellowstone, where it is located
This giant is located in the west of America, more precisely, in the northwest, in the region of Wyoming. First discovered dangerous mountain in 1960, she was spotted by a satellite. The size of the giant is about 72 x 55 kilometers, and this is almost a third of the 900,000 hectares of the entire Yellowstone national park, more precisely, its park part.
The Yellowstone volcano today stores in its depths a huge amount of hot magma, the temperature of which reaches 1000 degrees. It is to her that tourists owe many hot springs. The fire bubble is located at a depth of almost 8 kilometers.
Yellowstone eruptions
Many thousands of years ago, this giant already watered the earth with an abundant flow of lava, and sprinkled tons of ash on top. The largest volcanic eruption, which was also the first, according to scientists, occurred about two million years ago. It is assumed that then Yellowstone ejected more than 2.5 thousand cubic kilometers of rock, which flew up 50 kilometers from the surface of the earth. This is power!
About 1.2 million years ago, the formidable volcano erupted again. It was not as strong as the first one, and the emissions were ten times less.
The last, third disturbance occurred about 640 years ago. The volcanic eruption at that time cannot be called the largest, but it was during it that the walls of the crater collapsed, and today we can observe the caldera that appeared during that period.
Should we be concerned about Yellowstone erupting anytime soon?
With the beginning of the second millennium, scientists began to notice changes in the behavior of the Yellowstone volcano. What alarmed them?
- From 2007 to 2013, that is, in six years, the ground covering the caldera rose by two meters. Compared to the last twenty years before, the increase was only a few centimeters.
- New hot geysers have appeared.
- The strength and frequency of earthquakes in the caldera area have increased since 2000.
- Underground gases began to find their way out directly from the ground.
- The water temperature in nearby reservoirs increased by several degrees at once.
Residents of the North American continent were alarmed by this news. Scientists around the world agreed: there will be an eruption. When? Most likely, already this century.
Why is an eruption dangerous?
The largest eruption of the Yellowstone volcano is expected in our time. Scientists assume that its strength will be no less than during previous unrest. If we compare the power of the explosion, it can be equated to dropping more than a thousand atomic bombs on the ground. Such an explosion is capable of destroying everything within a radius of 150-160 kilometers, and another 1600 kilometers around will fall into the “dead zone”.
In addition, the eruption of Yellowstone can contribute to the start of eruptions of other volcanoes, and this will lead to the emergence of huge tsunamis. There are rumors that the United States government is preparing in full force for this event: durable shelters are being made, an evacuation plan is being created to other continents.
It is difficult to say whether this will be the largest volcanic eruption in history, but it is still dangerous, not only for the states, but for the whole world. If the emission height is 50 kilometers, then in two days a dangerous cloud of smoke will begin to actively spread. Residents of Australia and India will be the first to enter the disaster zone. For a period of more than two years, you will have to get used to the cold, since the sun's rays will not be able to break through the thickness of the ash, and winter will come unscheduled. Temperatures will drop to -25 degrees, and in some places to -50. In conditions of cold, lack of normal air, and hunger, only the strongest can survive.
Etna
This is an active stratovolcano, one of the most powerful in the world and the largest in Italy. Interested in the coordinates of Mount Etna? It is located in Sicily (right coast), near Catania and Messina. The geographic coordinates of Etna volcano are 37° 45’ 18" north latitude, 14° 59' 43" east longitude.
Now the height of Etna is 3429 meters, but it varies from eruption to eruption. This volcano is the highest point in Europe, outside the Alps, Caucasus Mountains and Pyrenees. This giant has a rival - the well-known Vesuvius, which at one time destroyed an entire civilization. But Etna is more than 2 times larger.
Etna is a harsh volcano. It has from 200 to 400 craters located on its sides. Once every three months, hot lava flows out of one of them, and about once every 150 years, really serious eruptions occur, which consistently destroy villages. However, this fact does not upset or frighten the local residents; they actively populate the slopes of the dangerous mountain.
List of eruptions: chronology of Etna's activity
About six thousand years ago, Etna got pretty crazy. During the eruption, a huge piece of its eastern part was broken off and thrown into the sea. In 2006, volcanologists published news that this fragment, falling into the water, created a huge tsunami.
The first eruption of this giant occurred, according to scientists, in 1226 BC.
In 44 BC, a powerful eruption occurred. An ash cloud extended all the way to Egypt, due to which there was no further harvest.
122 - a city called Catania is almost wiped off the face of the earth.
In 1669, the volcano, with its eruption, greatly modified the contours of the coast. Ursino Castle stood near the water, but after the eruption it was 2.5 km from the shore. Lava penetrated the walls of Catania, consuming the housing of 27 thousand people.
In 1928, an eruption destroyed the old city of Maskali. This event was remembered by believers; they believe that a real miracle happened. The fact is that before the religious procession the flow of hot lava stopped. A chapel was later built near it. Lava froze near the building in 1980.
During the period from 1991 to one of the most terrible eruptions, which practically destroyed the city of Zafferana.
The volcano's last major eruptions occurred in 2007, 2008, 2011 and 2015. But these were not the most serious disasters. Local residents call the mountain good, since the lava flows quietly down the sides and does not splash up in scary fountains.
Should we be afraid of Etna?
Due to the fact that the eastern part of the volcano has broken off, Etna now erupts effusively, that is, without an explosion, lava flows down its sides in slow streams.
Scientists today are concerned that the behavior of the giant is changing, and soon it will erupt explosively, that is, with an explosion. Such an eruption could affect thousands of people.
Guarapuava-Tamarana-Zarusas
The name of this volcano is difficult for even the most professional announcer to pronounce! But its name is not as scary as the way it erupted about 132 million years ago.
The nature of its eruption is explosive; such specimens accumulate lava for many millennia, and then pour it onto the earth in incredible quantities. This is what happened with this giant, which splashed out more than 8 thousand cubic kilometers of hot liquid.
This monster is located in the Trappian province of Parana-Etendeka.
We invite you to familiarize yourself with the largest volcanic eruptions in history.
Sakurajima
This volcano is located in Japan and is considered one of the most dangerous in the world. Since 1955, this giant has been in constant activity, which frightens local residents, and not only them.
The last eruption was in 2009, but not very serious compared to what happened in 1924.
The volcano began to signal its eruption with strong tremors. Most of the city's residents managed to leave the danger zone.
After this eruption, “Sakura Island” cannot be called an island. So much lava erupted from the mouth of this giant that an isthmus was formed that connected the island with another - Kyushu.
After this eruption, Sakurajima quietly poured out lava for about a year, which made the bottom of the bay much higher.
Vesuvius
It is located in Napoli and is the only “living” volcano in continental Europe.
Its most powerful eruption occurred in 79. In August, 24 woke up from hibernation and destroyed the city Ancient Rome: Herculaneum, Pompeii and Stabiae.
The last major volcanic eruption occurred in 1944.
The height of this formidable giant is 1281 meters.
Colima
Located in Mexico. This is one of the most dangerous representatives of its kind. It has erupted more than forty times since 1576.
The last strong eruption occurred in 2005, on June 8. The government urgently evacuated residents of nearby villages, as a huge cloud of ash rose above them - more than five kilometers in height. This threatened people's lives.
The highest point of this formidable monster is 4625 meters. Today, the volcano poses a danger not only to residents of Mexico.
Galeras
Located in Colombia. The height of this giant reaches 4276 meters. Over the past seven thousand years, about six major eruptions have occurred.
In 1993, one of the eruptions began. Unfortunately, on the territory of the volcano there were carried out research papers, and six geologists never returned home.
In 2006, the volcano again threatened to flood the surrounding area with lava, so people were evacuated from local settlements.
Mauna Loa
This is the formidable guardian of the Hawaiian Islands. It is considered the largest volcano on all Earth. The volume of this giant, taking into account the underwater part, is about 80 thousand cubic kilometers.
The last time a strong eruption was recorded was in 1950. And the most recent, but not strong, happened in 1984.
Mauna Loa is on the list of the most powerful, dangerous and largest volcanoes in the world.
Teide
This is a dormant monster, the awakening of which all the inhabitants of Spain fear. The last eruption occurred in 1909; today the formidable mountain shows no activity.
If this volcano decides to wake up, and it has been resting for more than a hundred years, then it will not be the most pleasant time for the residents of the island of Tenerife, as well as for the whole of Spain.
We have not named all the latest major volcanic eruptions. As stated at the beginning of the article, there are about six hundred active ones. People living in areas of active volcanoes are in fear every day, because an eruption is a terrible natural disaster that claims thousands of lives.
August 24-25, 79 AD an eruption occurred that was considered extinct Vesuvius volcano, located on the shores of the Gulf of Naples, 16 kilometers east of Naples (Italy). The eruption led to the destruction of four Roman cities - Pompeii, Herculaneum, Oplontium, Stabia - and several small villages and villas. Pompeii, located 9.5 kilometers from the crater of Vesuvius and 4.5 kilometers from the base of the volcano, was covered with a layer of very small pieces of pumice about 5-7 meters thick and covered with a layer of volcanic ash. With the onset of night, lava flowed from the side of Vesuvius, everywhere fires started, and the ash made it difficult to breathe. On August 25, along with an earthquake, a tsunami began, the sea retreated from the shores, and a black thundercloud hung over Pompeii and surrounding cities, hiding the Misensky cape and the island of Capri. Most of the population of Pompeii was able to escape, but about two thousand people died on the streets and in the houses of the city from poisonous sulfur dioxide gases. Among the victims was the Roman writer and scientist Pliny the Elder. Herculaneum, located seven kilometers from the crater of the volcano and about two kilometers from its base, was covered with a layer of volcanic ash, the temperature of which was so high that all wooden objects were completely charred. The ruins of Pompeii were accidentally discovered at the end of the 16th century, but systematic Excavations began only in 1748 and are still ongoing, along with reconstruction and restoration.
March 11, 1669 an eruption occurred Mount Etna in Sicily, which lasted until July of the same year (according to other sources, until November 1669). The eruption was accompanied by numerous earthquakes. Lava fountains along this fissure gradually moved downwards, and the largest cone formed near the city of Nikolosi. This cone is known as Monti Rossi (Red Mountain) and is still clearly visible on the slope of the volcano. Nikolosi and two nearby villages were destroyed on the first day of the eruption. In another three days, lava flowing south down the slope destroyed four more villages. At the end of March, two larger cities were destroyed, and at the beginning of April, lava flows reached the outskirts of Catania. Lava began to accumulate under the fortress walls. Some of it flowed into the harbor and filled it. On April 30, 1669, lava flowed through top part fortress walls. The townspeople built additional walls across the main roads. This stopped the advance of the lava, but the western part of the city was destroyed. The total volume of this eruption is estimated at 830 million cubic meters. Lava flows burned 15 villages and part of the city of Catania, completely changing the configuration of the coast. According to some sources, 20 thousand people, according to others - from 60 to 100 thousand.
October 23, 1766 on the island of Luzon (Philippines) began to erupt Mayon volcano. Dozens of villages were swept away and incinerated by a huge lava flow (30 meters wide), which went down the eastern slopes for two days. Following the initial explosion and flow of lava, Mayon Volcano continued to erupt for four more days, spewing a large number of steam and watery mud. Grayish-brown rivers ranging from 25 to 60 meters wide fell down the slopes of the mountain within a radius of up to 30 kilometers. They completely swept away roads, animals, villages with people on their way (Daraga, Kamalig, Tobaco). More than 2,000 residents died during the eruption. Basically, they were swallowed up by the first lava flow or secondary mud avalanches. For two months, the mountain spewed ash and poured lava onto the surrounding area.
April 5-7, 1815 an eruption occurred Tambora volcano on the Indonesian island of Sumbawa. Ash, sand and volcanic dust were thrown into the air to a height of 43 kilometers. Stones weighing up to five kilograms were scattered over a distance of up to 40 kilometers. The Tambora eruption affected the islands of Sumbawa, Lombok, Bali, Madura and Java. Subsequently, under a three-meter layer of ash, scientists found traces of the dead kingdoms of Pecat, Sangar and Tambora. Simultaneously with the volcanic eruption, huge tsunamis 3.5-9 meters high were formed. Having flown away from the island, the water fell on neighboring islands and drowned hundreds of people. About 10 thousand people died directly during the eruption. At least 82 thousand more people died from the consequences of the disaster - hunger or disease. The ash that shrouded Sumbawa destroyed crops and buried the irrigation system; acid rain poisoned the water. For three years after Tambora's eruption, the entire globe was enveloped in a shroud of dust and ash particles, reflecting some of the sun's rays and cooling the planet. The next year, 1816, Europeans felt the consequences of a volcanic eruption. It entered the annals of history as “the year without summer.” The average temperature in the Northern Hemisphere fell by about one degree, and in some areas - even by 3-5 degrees. Large areas of crops suffered from spring and summer frosts on the soil, and famine began in many areas.
August 26-27, 1883 an eruption occurred Krakatoa volcano, located in the Sunda Strait between Java and Sumatra. Houses on nearby islands collapsed due to tremors. On August 27, at about 10 o'clock in the morning, a gigantic explosion occurred, an hour later - a second explosion of the same force. More than 18 cubic kilometers of rock debris and ash shot up into the atmosphere. The waves of the tsunami caused by the explosions instantly swallowed up cities, villages, and forests on the coasts of Java and Sumatra. Many islands disappeared under water along with the population. The tsunami was so powerful that it went around almost the entire planet. In total, on the coasts of Java and Sumatra, 295 cities and villages were wiped off the face of the earth, over 36 thousand people died, and hundreds of thousands were left homeless. The coasts of Sumatra and Java have changed beyond recognition. On the coast of the Sunda Strait, fertile soil was washed away down to the rocky base. Only a third of the island of Krakatoa survived. In terms of the amount of water and rock moved, the energy of the Krakatoa eruption is equivalent to the explosion of several hydrogen bombs. The strange glow and optical phenomena persisted for several months after the eruption. In some places above the Earth, the sun appeared blue and the moon appeared bright green. And the movement of dust particles ejected by the eruption in the atmosphere allowed scientists to establish the presence of a “jet” stream.
May 8, 1902 Mont Pele volcano, located on Martinique, one of the Caribbean islands, literally tore into pieces - four strong explosions were heard, similar to cannon shots. They threw out a black cloud from the main crater, which was pierced by flashes of lightning. Since the emissions did not come through the top of the volcano, but through side craters, all volcanic eruptions of this type have since been called “Peleian”. Superheated volcanic gas, due to its high density and high speed of movement, spread above the ground itself, penetrated into all the cracks. A huge cloud covered the area of complete destruction. The second zone of destruction stretches another 60 square kilometers. This cloud, formed from super-hot steam and gases, weighed down by billions of particles of hot ash, moving at a speed sufficient to carry fragments of rocks and volcanic emissions, had a temperature of 700-980 ° C and was able to melt glass. Mont Pele erupted again on May 20, 1902, with almost the same force as on May 8. The Mont Pelee volcano, breaking into pieces, destroyed one of the main ports of Martinique, Saint-Pierre, along with its population. 36 thousand people died instantly, hundreds of people died from side effects. The two survivors became celebrities. Shoemaker Leon Comper Leander managed to escape within the walls of his own house. He miraculously survived, although he received severe burns to his legs. Louis Auguste Cypress, nicknamed Samson, was in a prison cell during the eruption and remained there for four days, despite serious burns. After being rescued, he was pardoned, soon he was hired by the circus and during performances he was shown as the only surviving resident of Saint-Pierre.
June 1, 1912 eruption began Katmai volcano in Alaska, which had been dormant for a long time. On June 4, ash material was ejected, which, mixed with water, formed mud flows; on June 6, an explosion of colossal force occurred, the sound of which was heard in Juneau 1,200 kilometers away and in Dawson 1,040 kilometers from the volcano. Two hours later a second explosion occurred enormous power and in the evening - the third. Then, for several days, there was an almost continuous eruption of colossal amounts of gases and solid products. During the eruption, about 20 cubic kilometers of ash and debris burst out of the volcano. The deposition of this material formed a layer of ash ranging from 25 centimeters to 3 meters thick, and much more near the volcano. The amount of ash was so great that for 60 hours there was complete darkness around the volcano at a distance of 160 kilometers. On June 11, volcanic dust fell in Vancouver and Victoria at a distance of 2200 km from the volcano. In the upper layers of the atmosphere it spread throughout the entire territory North America and fell in large quantities in the Pacific Ocean. For a whole year, small ash particles moved in the atmosphere. Summer across the planet turned out to be much colder than usual, since more than a quarter of the sun's rays falling on the planet were retained in the ash curtain. In addition, in 1912, amazingly beautiful scarlet dawns were celebrated everywhere. At the site of the crater, a lake with a diameter of 1.5 kilometers formed - the main attraction of the Katmai National Park and Preserve, formed in 1980.
December 13-28, 1931 an eruption occurred volcano Merapi on the island of Java in Indonesia. Over two weeks, from December 13 to 28, the volcano erupted a stream of lava about seven kilometers long, up to 180 meters wide and up to 30 meters deep. The white-hot stream scorched the earth, burned the trees and destroyed all the villages in its path. In addition, both slopes of the volcano exploded, and erupted volcanic ash covered half of the island of the same name. During this eruption, 1,300 people died. The eruption of Mount Merapi in 1931 was the most destructive, but far from the last.
In 1976, a volcanic eruption killed 28 people and destroyed 300 houses. Significant morphological changes occurring in the volcano caused another disaster. In 1994, the dome that had formed in previous years collapsed, and the resulting massive release of pyroclastic material forced the local population to leave their villages. 43 people died.
In 2010, the number of victims from the central part of the Indonesian island of Java was 304 people. The list of dead included those who died from exacerbations of lung and heart disease and other chronic diseases caused by ash emissions, as well as those who died from injuries.
November 12, 1985 eruption began Ruiz Volcano in Colombia, considered extinct. On November 13, several explosions were heard one after another. The power of the strongest explosion, according to experts, was about 10 megatons. A column of ash and rock debris rose into the sky to a height of eight kilometers. The eruption that began caused the instant melting of the vast glaciers and eternal snows lying on the top of the volcano. The main blow fell on the city of Armero, located 50 kilometers from the mountain, which was destroyed in 10 minutes. Of the 28.7 thousand residents of the city, 21 thousand died. Not only Armero was destroyed, but also a number of villages. Settlements such as Chinchino, Libano, Murillo, Casabianca and others were severely damaged by the eruption. Mudflows damaged oil pipelines, cutting off fuel supplies to the southern and western parts of the country. As a result of the sudden melting of the snow lying in the Nevado Ruiz Mountains, nearby rivers overflowed their banks. Powerful flows of water washed away roads, demolished power and telephone line supports, and destroyed bridges. According to the official statement of the Colombian government, as a result of the eruption of the Ruiz volcano, 23 thousand people died or went missing, and about five thousand were seriously injured and maimed. About 4,500 residential buildings and administrative buildings were completely destroyed. Tens of thousands of people were left homeless and without any means of subsistence. Colombia's economy suffered significant damage.
June 10-15, 1991 an eruption occurred Volcano Pinatubo on the island of Luzon in the Philippines. The eruption began quite quickly and was unexpected, since the volcano became active after more than six centuries of hibernation. On June 12, the volcano exploded, throwing a mushroom cloud into the sky. Streams of gas, ash and rocks melted to a temperature of 980°C rushed down the slopes at speeds of up to 100 kilometers per hour. For many kilometers around, all the way to Manila, day turned into night. And the cloud and the ash falling from it reached Singapore, which is 2.4 thousand kilometers away from the volcano. On the night of June 12 and the morning of June 13, the volcano erupted again, throwing ash and flames 24 kilometers into the air. The volcano continued to erupt on June 15 and 16. Mud flows and water washed away houses. As a result of numerous eruptions, approximately 200 people died and 100 thousand were left homeless
The material was prepared based on information from open sources
Today we will talk about the most destructive volcanoes in human history.
The eruption attracts, frightens and fascinates us at the same time. Beauty, entertainment, spontaneity, enormous danger for humans and all living things - all this is inherent in this violent natural phenomenon.
So, let's look at volcanoes, whose eruptions have caused the destruction of vast territories and mass extinctions.
The most famous active volcano is Vesuvius. It is located on the shores of the Gulf of Naples, 15 km from Naples. With a relatively low altitude (1280 meters above sea level) and “youth” (12 thousand years), it is rightfully considered the most recognizable in the world.
Vesuvius is the only active volcano on the European continent. It poses a great danger due to the dense population near the silent giant. Huge numbers of people are at risk of being buried under thick lava every day.
The last eruption, which managed to wipe out as many as two Italian cities, happened quite recently, in the midst of World War II. However, the eruption of 1944 in terms of the scale of the catastrophe cannot be compared with the events of August 24, 79 AD. Devastating consequences from that day still boggle our imagination. The eruption lasted more than a day, during which ash and dirt mercilessly destroyed the glorious city of Pompeii.
Until that moment, the local residents had no idea about the impending danger; they were let down by a very familiar attitude towards the formidable Vesuvius, as if it were an ordinary mountain. The volcano gave them fertile soil rich in minerals. Abundant harvests were the reason that the city was quickly populated, developed, gained some prestige and even became a vacation spot for the then aristocracy. Soon they built Theatre of Drama and one of the largest amphitheaters in Italy. Some time later, the region gained fame as the calmest and most prosperous place on the whole Earth. Could people have guessed that this flourishing area would be covered by merciless lava? That the rich potential of this region will never be realized? That all its beauty, improvement, and cultural development will be erased from the face of the Earth?
The first shock, which should have alerted the residents, was a strong earthquake, as a result of which many buildings in Herculaneum and Pompeii were destroyed. However, people who had arranged their life so well were in no hurry to leave their settled place. Instead, they restored the buildings in an even more luxurious, new style. At times there were minor earthquakes that no one paid attention to. special attention. This was their fatal mistake. Nature itself gave signs of approaching danger. However, nothing disturbed the calm way of life of the inhabitants of Pompeii. And even when on August 24 a frightening roar was heard from the bowels of the earth, the townspeople decided to flee within the walls of their houses. At night the volcano woke up completely. People fled to the sea, but the lava caught up with them near the shore. Soon their fate was decided - almost everyone ended their lives under a thick layer of lava, dirt and ash.
The next day, the elements mercilessly attacked Pompeii. Most of the townspeople, whose number reached 20 thousand, managed to leave the city even before the disaster began, but about 2 thousand still died on the streets. Human. The exact number of victims has not yet been established, since the remains are found outside the city, in the surrounding area.
Let's try to feel the scale of the disaster by turning to the work of the Russian painter Karl Bryullov.
The next major eruption occurred in 1631. It should be noted that a large number of victims were not due to a powerful emission of lava and ash, but due to the high population density. Just imagine, sad historical experience did not impress people enough - they still densely settled and continue to settle near Vesuvius!
Volcano Santorini
Today, the Greek island of Santorini is a tasty morsel for tourists: white stone houses, cozy atmospheric streets, scenic view. There is only one thing that overshadows the romance - the proximity to the most formidable volcano in the world.
Santorini is an active shield volcano located on the island of Thira in the Aegean Sea. Its strongest eruption was 1645-1600 BC. e. caused the death of Aegean cities and settlements on the islands of Crete, Thira and the coast Mediterranean Sea. The power of the eruption is impressive: it is three times stronger than the Krakatoa eruption and equals seven points!
Of course, such a strong explosion managed not only to reshape the landscape, but also change the climate. Huge cubes of ash thrown into the atmosphere prevented the sun's rays from touching the Earth, which led to global cooling. The fate of the Minoan civilization, the center of which was the island of Thira, is shrouded in mystery. The earthquake warned local residents about the impending disaster, they left in time native land. When a huge amount of ash and pumice came out from the interior of the volcano, the volcanic cone collapsed under the force of its own gravity. Sea water poured into the abyss, which formed a huge tsunami that washed away nearby settlements. There was no more Mount Santorini. A huge oval chasm, the volcanic caldera, was forever filled with the waters of the Aegean Sea.
Recently, researchers found that the volcano has become more active. Almost 14 million cubic meters of magma have accumulated in it - it seems that Sentorini can reassert itself!
Volcano Unzen
The Unzen volcanic complex, which consists of four domes, became a real synonym for disaster for the Japanese. It is located on the Shimabara Peninsula, its height is 1500 m.
In 1792, one of the most destructive eruptions in human history occurred. At one point, a 55-meter tsunami arose, destroying more than 15 thousand inhabitants. Of these, 5 thousand died during the landslide, 5 thousand drowned during the tsunami that hit Higo, 5 thousand - from the wave returning to Shimabara. The tragedy is forever etched in the hearts of the Japanese people. Helplessness in the face of the raging elements, the pain from the loss of a huge number of people was immortalized in numerous monuments that we can see in Japan.
After this terrible event, Unzen fell silent for almost two centuries. But in 1991 another eruption occurred. 43 scientists and journalists were buried under the pyroplastic flow. Since then, the volcano has erupted several times. Currently, although it is considered weakly active, it is under close monitoring by scientists.
Vulkae Tambora
Volcano Tambora is located on the island of Sumbawa. Its eruption in 1815 is rightfully considered the most powerful eruption in human history. It is possible that more powerful eruptions have occurred during the existence of the Earth, but we have no information about this.
So, in 1815, nature went wild: an eruption occurred with a magnitude of 7 on the scale of eruption intensity (explosive force) of a volcano, the maximum value being 8. The disaster shocked the entire Indonesian archipelago. Just think about it, the energy released during the eruption is equal to the energy of two hundred thousand atomic bombs! 92 thousand people were killed! Places with once fertile soil turned into lifeless space, resulting in a terrible famine. Thus, 48 thousand people died from hunger on the island of Sumbawa, 44 thousand on the island of Lambok, 5 thousand on the island of Bali.
However, the consequences were observed even far from the eruption - the climate of all of Europe underwent changes. The fateful year of 1815 was called “the year without summer”: the temperature became noticeably lower, and in a number of European countries it was not even possible to harvest the harvest.
Volcano Krakatoa
Krakatau is an active volcano in Indonesia, located between the islands of Java and Sumatra in the Malay Archipelago in the Sunda Strait. Its height is 813 m.
Before the 1883 eruption, the volcano was much higher and consisted of one large island. However, an eruption in 1883 destroyed the island and the volcano. On the morning of August 27, Krakatoa fired four strong shots, each of which resulted in a powerful tsunami. Huge masses of water poured into populated areas with such speed that residents did not have time to climb a nearby hill. The water, sweeping away everything in its path, raked in crowds of frightened people and carried them away, turning the once flourishing lands into a lifeless space full of chaos and death. So, the tsunami caused the death of 90% of those killed! The rest fell to volcanic debris, ash and gas. Total number the victims amounted to 36.5 thousand people.
Most of the island went under water. Ashes captured the whole of Indonesia: the sun was not visible for several days, the islands of Java and Sumatra were covered in pitch darkness. On the other side of the Pacific Ocean the sun has become Blue colour due to the huge amount of ash released during the eruption process. Volcanic debris released into the atmosphere managed to change the color of sunsets around the world for three whole years. They turned bright red and it seemed as if nature itself symbolized human death with this unusual phenomenon.
30 thousand people died as a result of the powerful eruption of the Mont Pelee volcano, which is located in Martinique, the most beautiful island Caribbean Sea. The fire-breathing mountain spared nothing; everything was destroyed, including the nearby elegant, cozy city of Saint-Pierre - the Paris of the West Indies, in the construction of which the French invested all their knowledge and strength.
The volcano began its inactive activity back in 1753. However, rare emissions of gases, flames and the absence of serious explosions gradually established the fame of Mont Pele as a capricious, but by no means formidable volcano. Subsequently, he became only part of the beauty natural landscape and served for the residents rather as a decoration of their area. Despite this, when in the spring of 1902, when Mont-Pele began to broadcast danger with tremors and a column of smoke, the townspeople did not hesitate. Sensing trouble, they decided to flee in time: some sought refuge in the mountains, others in the water.
Their determination was seriously affected by the huge number of snakes that slid down the slopes of Mont Pele and filled the entire city. Victims from the bites, then from the boiling lake, which was located not far from the crater, overflowed its banks and poured into the back part of the city in a huge stream - all this convinced residents of the need for urgent evacuation. However, the local government considered these precautions unnecessary. The mayor of the city, extremely concerned about the upcoming elections, was too interested in the turnout of citizens at such an important political event. He took the necessary measures to ensure that the population did not leave the city; he personally persuaded the residents to stay. As a result, most of them did not attempt to escape; those who escaped returned, resuming their usual way of life.
On the morning of May 8, a deafening roar was heard, a huge cloud of ash and gases flew out of the crater, instantly descended along the slopes of Mont Pele and... swept away everything in its path. In one minute this amazing, thriving town was completely destroyed. Factories, houses, trees, people - everything was melted, torn out, poisoned, burned, tormented. It is believed that the death of the unfortunates occurred in the first three minutes. Of the 30 thousand inhabitants, only two were lucky enough to survive.
On May 20, the volcano exploded again with the same force, which led to the death of 2 thousand rescuers who were raking the ruins of the destroyed city at that moment. On August 30, a third explosion occurred, leading to the death of thousands of residents of nearby villages. Mont Pele erupted several more times until 1905, after which it went into hibernation until 1929, when a rather powerful eruption occurred, however, without causing casualties.
Nowadays, the volcano is considered inactive, Saint-Pierre is being restored, but after these terrible events it has little chance of regaining the status of the most beautiful city Martinique.
Volcano Nevado Del Ruiz
Due to its impressive height (5400m), Nevado del Ruiz is rightfully considered the highest active volcano in the Andes mountain range. Its top is shrouded in ice and snow - that is why its name is “Nevado”, which means “snowy”. It is located in the volcanic zone of Colombia - the Caldas and Tolima regions.
Nevado del Ruiz is one of the deadliest volcanoes in the world for a reason. Eruptions leading to mass death have occurred three times already. In 1595, over 600 people were buried under the ashes. In 1845, a strong earthquake killed 1 thousand inhabitants.
And finally, in 1985, when the volcano was already considered dormant, 23 thousand people died. It should be noted that the cause of the latest disaster was the outrageous negligence of the authorities, who did not consider it necessary to monitor volcanic activity. On this moment 500 thousand residents of nearby areas are at risk of becoming victims of a new eruption every day.
So, in 1985, the crater of the volcano ejected powerful gas-pyroclastic flows. Because of them, the ice at the top melted, which led to the formation of lahars - volcanic flows that instantly moved down the slopes. This avalanche of water, clay, and pumice destroyed everything in its path. Destroying rocks, soil, plants and absorbing it all, the lahars quadrupled during the journey!
The thickness of the streams was 5 meters. One of them destroyed the city of Armero in an instant; out of 29 thousand inhabitants, 23 thousand died! Many of the survivors died in hospitals as a result of infection, epidemic typhus and yellow fever. Among all the volcanic disasters known to us, Nevado del Ruiz ranks fourth in terms of the number of human deaths. Devastation, chaos, disfigured human bodies, screams and moans - this is what appeared before the eyes of the rescuers who arrived the next day.
To understand the horror of the tragedy, let's take a look at the now famous photograph of journalist Frank Fournier. It shows 13-year-old Omaira Sanchez, who, finding herself among the rubble of buildings and unable to get out, bravely fought for her life for three days, but was unable to win this unequal battle. You can imagine how many lives of such children, teenagers, women, and old people were taken by the raging elements.
Toba is located on the island of Sumatra. Its height is 2157 m, it has the largest caldera in the world (area 1775 sq. km.), in which it formed largest lake of volcanic origin.
Toba is interesting because it is a supervolcano, i.e. From the outside it is practically invisible; it can only be seen from space. We can be on the surface of this kind of volcano for thousands of years, and only learn about its existence at the moment of a catastrophe. It is worth noting that while an ordinary fire-breathing mountain has an eruption, such a supervolcano has an explosion.
The Toba eruption, which occurred during the last ice age, is considered one of the most powerful during the existence of our planet. 2800 km³ of magma came out of the volcano’s caldera, and the ash deposits that covered South Asia, Indian Ocean, Arabian and South China Seas, reached 800 km³. Thousands of years later, scientists discovered the smallest ash particles 7 thousand km away. from a volcano on the territory of the African Lake Nyasa.
As a result of the huge amount of ash emitted by the volcano, the sun was obscured. A real volcanic winter set in, lasting several years.
The number of people decreased sharply - only a few thousand people managed to survive! It is with the Toba explosion that the “bottleneck” effect is associated - a theory according to which in ancient times the human population was distinguished by genetic diversity, but most of the people suddenly died out as a result of a natural disaster, thus reducing the gene pool.
El Chichon is the southernmost volcano in Mexico, located in the state of Chiapas. Its age is 220 thousand years.
It is noteworthy that until recently local residents were not at all worried about the proximity to the volcano. The issue of security was also not relevant because the areas adjacent to the volcano were rich in dense forests, which indicated the long-term hibernation of El Chichon. However, on March 28, 1982, after 12 hundred years of peaceful sleep, the fire-breathing mountain demonstrated its full destructive power. The first stage of the eruption entailed a powerful explosion, as a result of which a huge ash column (height - 27 km) formed over the crater, which covered an area within a radius of 100 km in less than an hour.
A huge amount of tephra was released into the atmosphere, and heavy ashfalls occurred around the volcano. About 2 thousand people died. It should be noted that the evacuation of the population was poorly organized and the process was slow. Many residents left the territory, but after a while they returned, which, of course, led to dire consequences for them.
In May of the same year, the next eruption occurred, which was even more powerful and destructive than the previous one. The convergence of the pyroclastic flow left a scorched strip of land and a thousand human deaths.
The disaster was not going to stop there. Local residents suffered two more Plinian eruptions, which generated a 29-kilometer column of ash. The number of victims again reached a thousand people.
The consequences of the eruption affected the country's climate. A huge cloud of ash covered 240 square km; in the capital, visibility was only a few meters. Due to ash particles hanging in the layers of the stratosphere, a noticeable cooling occurred.
In addition, the natural balance has been disrupted. Many birds and animals were destroyed. Some types of insects began to grow rapidly, which resulted in the destruction of most of the crop.
The shield volcano Laki is located in the south of Iceland in the Skaftafell Park (since 2008 it has been part of the Vatnajökull National Park). The volcano is also called the Laki crater, because. it is part of a mountain system consisting of 115 craters.
In 1783, one of the most powerful eruptions occurred, which set a world record for the number of human casualties! In Iceland alone, almost 20 thousand lives were lost – that’s one third of the population. However, the volcano carried its destructive impact beyond the borders of its country - death even reached Africa. There are many destructive, deadly volcanoes on Earth, but Lucky is the only one of his kind who killed slowly, gradually, in various ways.
The most interesting thing is that the volcano warned residents about the upcoming danger as best it could. Seismic displacements, uplifting land, raging geysers, explosions of pillars into the air, whirlpools, boiling of the sea - there were plenty of signs of an imminent eruption. For several weeks in a row, the land literally shook under the feet of the Icelanders, which, of course, scared them, but no one attempted to escape. People were confident that their homes were strong enough to protect them from the eruption. They hunkered down at home, tightly locking the windows and doors.
In January, the formidable neighbor made himself known. He raged until June. During these six months of eruptions, Mount Skaptar-Ekul split open and a huge 24-meter chasm formed. Harmful gases came out and formed a powerful lava flow. Imagine how many such flows there were - hundreds of craters erupted! When the flows reached the sea, the lava solidified, but the water boiled, and all the fish within a radius of several kilometers from the shore died.
Sulfur dioxide covered the entire territory of Iceland, which led to acid rain and destruction of vegetation. As a result, agriculture suffered greatly, and famine and disease struck the surviving inhabitants.
Soon “Hungry Haze” reached all of Europe, and a few years later to China. The climate changed, dust particles did not allow the rays of the sun to pass through, summer never came. Temperatures dropped by 1.3 ºC, leading to cold-related deaths, crop failure and famine in many European countries. The eruption even left its mark on Africa. Due to the abnormal cold, the temperature contrast was minimal, which led to a decrease in monsoon activity, drought, shallowing of the Nile, and crop failure. Africans died en masse from starvation.
Volcano Etna
Mount Etna is the highest active volcano in Europe and one of the largest volcanoes in the world. It is located on the east coast of Sicily, near the cities of Messina and Catania. Its circumference is 140 km and covers an area of approximately 1.4 thousand square meters. km.
There have been approximately 140 powerful eruptions of this volcano in modern times. In 1669 Catania was destroyed. In 1893, the Silvestri crater appeared. In 1911 a northeastern crater formed. In 1992 a huge lava flow stopped near Zafferana Etnea. The last time the volcano erupted lava was in 2001, destroying the cable car leading to the crater.
Currently, the volcano is a popular place for hiking and skiing. Several half-empty towns are located at the foot of the fire-breathing mountain, but few dare to risk living there. Here and there, gases escape from the depths of the earth; it is impossible to predict when, where and with what power the next eruption will occur.
Volcano Merapi
Marapi is the most active active volcano in Indonesia. It is located on the island of Java near the city of Yogyakarta. Its height is 2914 meters. This is a relatively young, but quite restless volcano: since 1548 it has erupted 68 times!
The close proximity to such an active fire-breathing mountain is very dangerous. But, as is usually the case in economically undeveloped countries, local residents, without thinking about the risk, appreciate the benefit that the mineral-rich soil gives them - abundant harvests. Thus, about 1.5 million people currently live near Marapi.
Strong eruptions occur every 7 years, smaller ones every couple of years, and the volcano smokes almost daily. Disaster of 1006 The Javanese-Indian kingdom of Mataram was completely destroyed. In 1673 One of the most powerful eruptions occurred, as a result of which several cities and villages were wiped off the face of the Earth. There were nine eruptions in the 19th century, 13 in the last century.
About 74 thousand years ago, the Toba volcano exploded in what is now Sumatra. This is the largest eruption in at least two million years. It is an order of magnitude larger than the Tambora eruption in the 19th century, which is considered the most powerful in modern history humanity. Toba ejected 2,800 cubic kilometers of magma, covered the surrounding area with a multi-meter layer of ash and filled the atmosphere with thousands of tons of sulfuric acid and sulfur dioxide. This event could increase the average annual temperature on the planet by 10 C for an entire decade, and cooling the climate to its previous level could take about a thousand years.
This happened in the Middle Paleolithic era, when the pinnacle of human technology was stone tools and fire production. Therefore, it is easy to explain the widespread belief in the scientific community that this eruption had an extremely serious impact on the human population. However, many evidence suggests that people did not suffer much. And this is one of those mysteries that cannot yet be explained.
Toba's catastrophe theory
As a result of volcanic eruptions, the main influence on the climate is ash and sulfur dioxide. This stuff can remain in the atmosphere for years, reflecting sunlight and causing global cooling for tens or hundreds of years. Endless winter, naturally, would have been a real disaster for the then inhabitants of the planet. For comparison, due to the eruption of nearby Tambora, 1816 went down in history as “the year without a summer.” There was no harvest all over the world, and famine began in some places. At the same time, only 115 cubic kilometers of magma erupted from Tambora, that is, 25 times less than from Toba.
In the 1990s, a scientist named Stanley Ambrose proposed the “Toba Catastrophe Theory.” In his opinion, the eruption practically destroyed people, reducing their number from one hundred to ten thousand. Africans are more genetically diverse than other races, which means that the rest of humanity at some point in its history experienced the effects of a bottleneck effect - a sharp decline in population that led to a loss of genetic diversity.
According to this theory, the culprits were a catastrophic volcanic eruption and the subsequent global cooling. The Africans, she argues, were helped by the hot climate of their homeland. All this seems extremely logical. But as scientists receive new evidence of the Toba eruption, the situation becomes more and more confusing. At this point in time, there is no consensus on how seriously the volcano has affected the Earth's climate.
Research in recent years
In 2010, researchers created a mathematical model based on the amount of polluting particles emitted into the atmosphere and the solar radiation reflected by them. The simulation showed that Toba's impact on the planet was much milder and less lasting than previously thought - a decrease in temperature of 3-5 degrees for 2-3 years. Naturally, this is a very serious cold snap. A decrease of even 1-2 degrees, as we remember, is already a “year without summer.” But perhaps it was not so terrible as to destroy 90% of the human population.
Later studies showed that sediment samples from Africa's Lake Malawi showed little difference in plant life before and after the eruption. But this should be expected first of all if we are talking about a winter that lasted a whole decade. Excavations on the coast South Africa did not detect any interruptions or changes in human activity in this area. A thin layer of volcanic glass fragments from the Toba eruption was found here, but the artifacts associated with people were the same before and after this layer.
In this regard, some scientists have suggested that life on a warm coast, rich in resources, contributed to the fact that people did not particularly feel the changes caused by the eruption. However, excavations in India, which is much closer to Toba, also did not record significant changes in the activities of human communities at the time of interest to us.
Man is a very tenacious creature
The volcano probably still had an impact on people - the largest eruption in history is very difficult not to notice. However, it is extremely unlikely that it wiped out 90% of the human population. In connection with the debunking of the Toba catastrophe theory, the question has arisen about what caused the bottleneck effect during the exit of people from Africa. The most accepted explanation today is the so-called “founder effect.” According to this hypothesis, small groups of people migrated from the dark continent, which limited the genetic diversity of their descendants, who subsequently settled throughout the world.
Perhaps the closest parallel to You today is the huge volcano beneath Yellowstone National Park. It had already erupted about two million years ago, and in scale this event was quite comparable to the explosion of Toba. The volume of ejected lava was then 2500 cubic kilometers. In the event of an eruption of this magnitude, people will have a very difficult time - many of the technologies that have appeared over the past few centuries will be adversely affected - from Agriculture to communications and aviation. In some respects, today's humanity is much more sensitive to such phenomena than at the time of the Toba eruption. Fortunately, according to most volcanologists, the likelihood of an eruption in Yellowstone is negligible. In addition, as Toba showed, humans are incredibly resilient members of the living world. In this respect, we are hardly inferior to rats and cockroaches.
Incredible facts
Mid-June this year marked 20 years since the catastrophic eruption of Mount Pinatubo, which resulted in a huge number Ash was released into the atmosphere and circled the globe, causing global temperatures to drop by 0.5 degrees Celsius the following year.
On this anniversary, we decided to highlight the largest volcanic eruptions as measured by the Volcanic Eruption Index (VEI), a classification system similar to a scale used to measure earthquake levels.
The system was developed in the 1980s, taking into account factors such as eruption volume, eruption speed and other quantitative variables. The scale ranges from 1 to 8, with each subsequent VEI being 10 times stronger than the previous one.
Over the past 10,000 years, there have been no eruptions of volcanoes with an index of 8, however, human history witnessed several powerful and destructive eruptions. Below are the 10 most powerful volcanic eruptions that have occurred over the past 4,000 years.
Huaynaputina, Peru - 1600, VEI 6
It was the largest volcanic eruption of all time in South American history. The explosion triggered mudflows that reached the Pacific Ocean, which was located 120 km from the scene of the events. Among other things, the explosion also appears to have affected the global climate. The summer of 1600 was one of the coldest in the previous 500 years. Ash from the explosion covered everything within a radius of 50 square kilometers.
Despite the fact that the mountain is quite high (4850 meters), no one expected it to erupt. It stands on the edge of a deep canyon, and its peak does not at all resemble the silhouette that is usually associated with possible eruptions. The cataclysm of 1600 damaged the nearby cities of Arequipa and Moquegau, which took a century to recover.
Krakatoa, Sunda Strait, Indonesia - 1883, VEI 6
The powerful explosion that occurred on August 26-27, 1883 was accompanied by loud peals for several months. The eruption of this stratovolcano, located along a volcanic island arc in the subduction zone of the Indo-Australian Plate, ejected huge amounts of rock, ash and pumice, and was heard thousands of kilometers away.
The explosion also triggered the development of a tsunami, the maximum wave height reached 40 meters, killing more than 34,000 people. Tidal sensors located 11,000 km from the Arabian Peninsula even recorded an increase in wave height.
While the island that had been Krakatoa's home before the eruption was left completely destroyed, new eruptions began in December 1927 and triggered the emergence of Anak Krakatoa ("Child of Krakatoa"), a cone at the center of the caldera resulting from the 1883 eruption. Anak Krakatoa comes to his senses from time to time, reminding everyone of his great parent.
Volcano Santa Maria, Guatemala - 1902, VEI 6
The eruption of Santa Maria in 1902 was one of the largest eruptions of the 20th century. A strong explosion occurred after almost 500 years of silence, leaving behind a large crater, about 1.5 km in diameter, on the southwestern flank of the mountain.
The symmetrical, tree-covered volcano is part of a chain of stratovolcanoes that rises along the Pacific plain of Guatemala's coast. From the moment of the strongest explosion, the volcano began to show its character too often. Thus, in 1922, an eruption occurred with a force of VEI 3, and in 1929, Santa Maria “issued” a pyroclastic flow (fast-moving and flammable clouds of gas and dust), which killed more than 5,000 people.
Novarupta, Alaska Peninsula - June 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 explosion of the 20th century. The powerful eruption triggered the release of 12.5 cubic kilometers of magma and ash into the air, which then settled on the ground within a radius of 7,800 square kilometers.
Mount Pinatubo, Luzon, Philippines - 1991, VEI 6
The catastrophic eruption of Pinatubo was a classic explosive eruption. The eruption released more than 5 cubic kilometers of by-products into the air and created a plume of ash that rose 35 kilometers into the atmosphere. Then all this fell on one village, the roofs of many of whose houses even collapsed under the weight of the ash.
The explosion also released several million tons of sulfur dioxide and other elements into the air, which spread throughout the world thanks to air flows and caused global temperatures to drop by 0.5 degrees Celsius next year.
Ambrym Island, Republic of Vanuatu – 50 AD, VEI 6+
The volcanic island, covering an area of 665 sq km, part of a tiny country in the south-west Pacific Ocean, witnessed one of the most spectacular eruptions in human history, when a huge amount of ash and ash was thrown into the atmosphere and a caldera 12 km in diameter was formed .
The volcano continues to be one of the most active in the world to this day. It has erupted about 50 times since 1774, and has proven to be the most dangerous neighbor for the people living nearby. In 1894, six people died as a result of being hit by volcanic bombs, and four people drowned in lava flows. In 1979, acid rain caused by a volcanic eruption burned several local residents.
Volcano Ilopango, El Salvador – 450 AD, VEI 6+
Although this mountain is located in the center of El Salvador, just a few miles east of the capital San Salvador, it has only experienced two eruptions in its history, the first being a very violent one. It covered much of Central and Western El Salvador with ash and ash, and destroyed early cities Maya, forcing the inhabitants to flee.
Trade routes were destroyed and the center of Mayan civilization moved from the mountainous areas of El Salvador to the lowland areas to the north in Guatemala. The eruption calderas are now one of the largest lakes in El Salvador.
Mount Thera, Santorini Island, Greece – 1610 BC, VEI 7
Geologists believe the Aegean island volcano Thera exploded with a force equivalent to several hundred atomic bombs. Although there is no record of an eruption, geologists think it was the largest explosion ever seen by man.
The island of Santorini (part of the archipelago of volcanic islands), on which the volcano is located, was home to the people of the Minoan civilization, although there are some indications that the inhabitants of the island suspected that the volcano “wanted” to explode and were able to evacuate in time. But even if we assume that the inhabitants managed to escape, their culture was still greatly damaged as a result of the eruption. It is also worth noting that the volcano provoked huge tsunami, and the huge release of sulfur dioxide into the atmosphere caused a global decrease in temperature and climate change subsequently.
Changbaishan Volcano, border between China and North Korea, 1000, VEI 7
Also known as Baitoushan Volcano, its eruption released so much volcanic material that even northern Japan, 1,200 km away, felt it. The eruption created a large caldera - almost 4.5 km in diameter and about 1 km in depth. The caldera is now Tianchi Lake, which is popular among tourists not only for its beauty, but also for the supposed unidentified creatures living in its depths.
The mountain last erupted in 1702 and geologists believe it is dormant. Gas emissions were recorded in 1994, but no evidence of renewed volcanic activity was observed.
Mount Tambora, Sumbawa Island, Indonesia - 1815, VEI 7
The explosion of Mount Tambora is the largest in the history of mankind, its explosiveness index is 7, which is a very high indicator. The volcano, which is still active, is one of the highest peaks in the Indonesian archipelago. The eruption reached its climax in April 1815, with an explosion so loud that it was heard on the island of Sumatra, which is located more than 1,930 km away. The death toll was 71,000, and clouds of heavy ash fell on many islands located at very long distance from the volcano.