The history of the Earth is closely linked to volcanic activity., those impressive phenomena that, over millions of years, have shaped the planet, altered the global climate and, at times, jeopardized the survival of entire species, including our own. Volcanoes are not only spectacular for their eruptions of lava and ash, but because they represent a crucial manifestation of the planet's internal processes, acting as agents of change at both the geological and social and climatic levels..
In this article we will travel through time and space to review the most historic volcanic eruptions.—and often tragic—that have shaped geological evolution and left an indelible mark on human civilization. Thanks to testimonies, scientific studies, and advances in volcanology, we now have a better understanding of how, where, and why these gigantic events occur, and what their most impactful consequences have been.
The importance of volcanoes in the history of the Earth
Volcanoes are true drivers of the planet's geological and climatic history.. For the last two million years, Major eruptive episodes have caused extinctions, climate changes and large-scale geographical transformations.. Not only do they shape the relief, but their emissions into the atmosphere They can alter global temperatures and affect life on Earth..
Volcanology, the science that studies these phenomena, has advanced significantly in recent decades thanks to modern instruments, ice core analysis, precise dating, and satellite observations. Large volcanoes, in addition to posing risks to nearby populations, are key to understanding past climate and the processes that have shaped the continents..
Volcanic Explosivity Index (VEI): how the power of an eruption is measured
The Volcanic Explosivity Index (VEI) is used to classify the magnitude and intensity of volcanic eruptions.Developed by volcanologists Christopher G. Newhall and Stephen Self, this scale ranges from 0 to 8 logarithms and evaluates various parameters, such as the amount of material ejected, the height of the eruptive column, and the duration of the event.
A VEI value of 1 corresponded to small, continuous eruptions such as those of Stromboli., while a VEI of 8 reflects epic cataclysms such as Taupo. The same VEI can imply different impacts depending on geography, climate, population density and associated phenomena such as tsunamis, mudflows or lahars..
The most devastating eruptions are not always the most explosive.; Often, the higher number of victims results from secondary factors, such as poor disaster management, proximity to human settlements, or the collapse of ecosystems and crops following the volcanic event.
Prehistoric volcanic eruptions with global impact
The first truly colossal eruptions on record date back long before the emergence of civilization.Among them, two stand out, which almost forced the extinction of humanity and whose traces are found all over the world.
- The eruption of Lake Toba (Sumatra, Indonesia)Approximately 75.000 years ago, this supervolcano had the most powerful known eruption of the last two million years, ejecting up to 2.800 cubic kilometers of material. Ash covered large areas of the planet And studies suggest that the human population declined dramatically, as almost all groups that had left Africa disappeared. It's estimated that global temperatures dropped dramatically, bringing the human species to the brink of extinction.
- The eruption of Thera (Santorini, Greece)About 3.600 years ago (1600 BC), the island of Santorini was the scene of a massive explosion that ejected material equivalent to four times the size of Krakatoa. At least four tsunamis were generated, devastating villages and radically altering the landscape of the Aegean Sea, contributing to the collapse of the Minoan civilization.
Historic eruptions that transformed geology and civilization
The chronicles of humanity are full of stories and testimonies of great eruptions that changed the course of history., from ancient times to the modern era. Many of them are documented by chroniclers, archaeologists, and, more recently, advanced scientific means.
Vesuvius (Italy, year 79): the destruction of Pompeii and Herculaneum
Mount Vesuvius, in the Bay of Naples, was the scene of one of the most documented eruptions of antiquity.On August 24, 79 AD, after centuries of apparent inactivity, the volcano erupted with enormous violence, spewing ash, lapilli, and toxic gases that buried the cities of Pompeii, Herculaneum, Oplontis, and Stabiae.
Pliny the Younger witnessed the catastrophe and recounted his experience through letters to his friend Tacitus., describing the eruption, the collapse of roofs due to the weight of volcanic materials and the advance of lethal pyroclastic flows.
- It is estimated that between 1.500 and 4.000 people died., although recent studies raise the figure due to remains found in villas, beaches and port warehouses.
- The ashes covered the city under a layer of up to 25 meters, keeping the skeletons and buildings exceptionally preserved, which has allowed us to reconstruct, in detail, the impact of the event.
- The eruption of Vesuvius gave its name to the term "Plinian eruptions", used for the most intense and sustained explosions.
The risk of Vesuvius remains even today due to its proximity to Naples, a metropolis of more than three million inhabitants.History shows that this volcano can have major eruptions every two thousand years.
Tambora (Indonesia, 1815): the eruption that changed the world's climate
Tambora is the protagonist of the deadliest volcanic eruption and the most significant climatic impact documented in modern history.On April 5, 1815, this Indonesian volcano ejected more than 160 cubic kilometers of material, collapsing its cone and generating a caldera six kilometers in diameter.
Its direct and indirect effects were devastating.:
- Between 60.000 and 120.000 people died., most of them due to hunger and subsequent illnesses (only 10.000 died immediately).
- The cloud of sulfur and ash altered the atmosphere and caused the "year without a summer" in 1816.: midsummer snowfall in the northern hemisphere, a drop of between 0,5ºC and 0,7ºC in global temperature, ruined crops and the worst famine of the XNUMXth century.
- The consequences spread to Europe and North America, with meteorological anomalies that inspired artistic and literary works, such as the myth of Frankenstein.
The Tambora eruption forever changed human perceptions of the power of nature and vulnerability to major volcanic events..
Krakatoa (Indonesia, 1883): the explosion that resonated around the world
Located in the Sunda Strait, Krakatoa erupted catastrophically in late August 1883The series of explosions culminated on August 27, when most of the island was blown to pieces, generating a shock wave that circled the globe several times and was heard 4.800 km away.
- The sound of the explosion is one of the loudest recorded in history., reaching 180 decibels at 160 kilometers away.
- It caused gigantic tsunamis up to 40 meters high. which devastated more than 160 villages and coastal towns on the islands of Java and Sumatra, causing the deaths of approximately 36.417 people.
- The eruptive column reached 80 kilometers in height and the ash dispersed globally, causing spectacular optical effects and temporary weather disturbances.
- The story of Krakatoa spread globally thanks to the advances of the telegraph., making it a symbol of the vulnerability of civilization to nature.
Ilopango (El Salvador, year 540): the forgotten cataclysm of Central America
Less than 20 kilometers from the center of San Salvador is the caldera of the Ilopango volcano., which, in 540 AD, produced the second largest explosion recorded in Central America in 84.000 years. Lake Ilopango, with an area of over 70 km², is today the silent witness of an episode that ejected some 84 cubic kilometers of material, burying crops, villages, and entire civilizations under layers of "young white earth.".
- The eruption devastated western, central and eastern El Salvador., with a layer of ash up to three meters thick over large areas, killing between 40.000 and 80.000 people immediately.
- The disaster caused a demographic and cultural crisis, forcing the migration of between 100.000 and 400.000 survivors, many of whom succumbed to lack of food and water in the following months and years.
- The Ilopango further aggravated the global cooling that had begun in 536 by another major eruption (probably in Iceland), contributing to the "Plague of Justinian" and a very serious crisis in Eurasia and the Mediterranean.
The Ilopango eruption has been an example of how Central American volcanoes have also had a global impact, often underestimated outside their immediate surroundings.
Mount Pelée (Martinique, 1902): the total tragedy in the Caribbean
On May 8, 1902, the city of Saint-Pierre, the most prosperous on the island of Martinique, was devastated in minutes by a pyroclastic flow from Mount Pelée.This explosion destroyed an entire city in a matter of minutes, killing more than 29.000 people. Only three survived, one of them, Ludger Sylbaris, thanks to his confinement in an underground cell.
- The eruption of Pelée was particularly lethal due to the lack of knowledge and preparation for volcanic risks.The nature and extent of the pyroclastic flows, which travel at over 100 km/h, destroying everything in their path, were unknown.
- The scientific work of Alfred Lacroix, a witness and scholar of the event, promoted the birth of modern volcanology and research into the risks associated with volcanoes..
Nevado del Ruiz (Colombia, 1985): the avoidable disaster
Nevado del Ruiz, in the Andes mountain range, was the scene of one of the worst catastrophes in the modern history of Latin America.On November 13, 1985, a relatively small eruption in terms of volume (0,02 km³, VEI 3) caused the glacier to melt and deadly lahars (mudflows) to form, which descended the valleys, devastating the town of Armero.
- Around 23.000 people died in Armero and material damage amounted to more than 7.700 billion dollars (at the time), affecting 20% of Colombian GDP.
- Despite prior signs of volcanic activity and the existence of risk maps, the lack of an adequate institutional response and alarm systems prevented mass evacuation.The tragedy of Omayra Sánchez, the girl trapped in mud and debris, became a symbol of the disaster.
The Nevado del Ruiz tragedy marked a turning point in volcanic disaster management and the social perception of geological risk..
Pinatubo (Philippines, 1991): the best-managed eruption of the XNUMXth century
On the island of Luzon, Mount Pinatubo erupted in June 1991 after centuries of apparent inactivity, generating one of the largest eruptions of the XNUMXth century. (VEI 6, 10 km³ of ejected material). The event caused the preventive evacuation of more than 200.000 people and a global temperature reduction of between 0,4°C and 0,6°C due to the emission of aerosols and sulfur dioxide into the stratosphere.
The immediate impact was relatively low in terms of casualties (932 deaths)., thanks to effective international management and response. However, material damage, the destruction of homes, and the collapse of infrastructure persisted for months.
Eyjafjallajökull (Iceland, 2010): the volcano that paralyzed Europe
This Icelandic subglacial volcano erupted on March 20, 2010, initially with basaltic lava fountains that attracted tourist interest.But on April 14, a shift to a hydrovolcanic mode occurred when magma contacted the glacier ice, generating highly fragmented explosions and very fine ash.
- The ash cloud was quickly dispersed towards Europe by the prevailing winds., creating the greatest aviation chaos in recent history: more than 100.000 flights were cancelled and 10 million passengers were left stranded.
- The event tested the international coordination of the Volcanic Ash Advisory Centres (VAACs) and the capacity to respond to volcanic crises in densely connected regions.
- The direct economic cost of the event is estimated at around $23.000 billion..
Laki (Iceland, 1783): the famine that influenced European history
The eruption of Lakagigar (Laki) in Iceland, between 1783 and 1784, expelled more than 120 million tons of sulfur dioxide, covering Europe in a toxic haze.Its effects resulted in the death of 80% of Icelandic livestock and famine for 25% of the population. The particles and gases traveled to the European continent, exacerbating the poverty and social crises that existed before the French Revolution.
- Falling temperatures and crop failures led to several years of widespread misery., demonstrating how an eruption thousands of miles away from major population centers can contribute to significant sociopolitical changes.
Historic volcanoes with a high death toll
Many volcanic eruptions went down in history not so much for their magnitude as for the number of victims they left behind.Here we summarize some of the deadliest:
- Tambora (1815): up to 85.000 deaths, mainly due to famine and associated diseases.
- Krakatoa (1883): more than 36.000 dead, most of them due to tsunamis.
- Mount Pelée (1902): 29.000 dead from pyroclastic flow.
- Nevado del Ruiz (1985): 23.080 dead from lahars.
- Unzen (Japan, 1792): 15.000 victims mainly due to a tsunami following the eruption.
- Santa Maria (Guatemala, 1902): more than 8.700 dead.
- Kelut (Indonesia, 1919): about 5.000 dead from the mudslide from the crater lake.
- Papandayan (Indonesia, 1772): 3.000 dead from the collapse of the volcano.
- Lamington (Papua New Guinea, 1951): 2.942 deaths from a Plinian-type eruption.
- Bump (Mexico, 1982): some 2.000 victims, the largest volcanic disaster in modern Mexican history.
- Lake Nyos (Cameroon, 1986): 1.746 dead due to sudden release of volcanic gases.
- La Soufrière (Saint Vincent, Caribbean, 1902): 1.565 dead.
- Agung (Indonesia, 1963): 1.138 dead from pyroclastic flows.
- Merapi (Indonesia, 1930): 1.363 dead.
- Pinatubo (Philippines, 1991): 932 deaths, an example of good emergency management despite its magnitude.
Premonitory eruptions of the Pleistocene and Holocene: the case of Taupo
Going back even further in time, the mega-eruption of Taupo volcano in New Zealand, about 26.500 years ago, ejected enough material to earn the maximum VEI index (8)An estimated 1.170 km³ of material was dispersed, covering the North Island with a layer of ignimbrite up to 200 meters thick. Such events are relatively rare, but they remind us of nature's latent destructive capacity.
Other volcanoes and eruptions of great importance
- Chaitén (Chile, 2008): The most violent eruption in Chile since 1932, with the evacuation of 6.000 people and the destruction of the city of the same name.
- Mount Saint Helens (United States, 1980)Considered the worst volcanic catastrophe in US history, with a 24-kilometer ash column, more than 350 km² of forest scorched, and 57 fatalities.
- Nevado del Huila (Colombia, 1994): Earthquake and lahar that devastated entire villages and caused around 1.000 casualties.
- Nyiragongo (Congo, 1977)The rapid emptying of the lava lake caused the deaths of hundreds of people in a matter of minutes.
Geological and climatic consequences of large volcanoes
Massive volcanic eruptions transcend local disasters and have global implications.By emitting sulfur aerosols and fine ash into the stratosphere, They reflect sunlight, lower the planet's temperature and alter weather patterns., as happened with Tambora, Pinatubo and Laki.
Currently, monitoring volcanic activity is key to risk mitigation.International coordination through satellites, sensors, and emergency networks allows us to partially anticipate the impact of future eruptions. But vulnerability remains high in densely populated areas, and geological events repeatedly remind us of the need to combine science, outreach, and investment in prevention.
The role of risk management in volcanic history
The impact of eruptions does not depend only on the force of nature, but also the human capacity to anticipate, respond, and learn from past mistakes. Examples like Pinatubo show that good management can save thousands of lives, while the Armero tragedy demonstrates the cost of inaction and lack of communication.
Volcanic history is a constant reminder of the need for study, understand and respect the limits of the planetEruptions have influenced the world's geology, climate, culture, and even demographics. They are part of Earth's dynamics, and their study is essential for planning the future and understanding the geological and human past.