Some eruptions cooled the global climate—inducing a volcanic winter—depending on the amount of sulfur dioxide emitted and the magnitude of the eruption. Before the present Holocene epoch, the criteria are less strict because of scarce data availability, partly since later eruptions have destroyed the evidence. Only some eruptions before the Neogene period (from 23 Mya to 2.58 Mya) are listed. Known large eruptions after the Paleogene period (from 66 Mya to 23 Mya) are listed, especially those relating to the Yellowstone hotspot, the Santorini caldera, and the Taupo Volcanic Zone.
Novarupta, Alaska Peninsula; 1912, June 6; VEI 6; 13 to 15 km3 (3.1 to 3.6 cu mi) of lava
Santa Maria, Guatemala; 1902, October 24; VEI 6; 20 km3 (4.8 cu mi) of tephra
Krakatoa, Indonesia; 1883, August 26–27; VEI 6; 21 km3 (5.0 cu mi) of tephra
Mount Tambora, Lesser Sunda Islands, Indonesia; 1815, Apr 10; VEI 7; 150 km3 (36 cu mi) of tephra; an estimated 200,000,000 t (220,000,000 short tons) of SO 2 were emitted, produced the "Year Without a Summer"
Grímsvötn, Northeastern Iceland; 1783–1785; Laki; 1783–1784; VEI 6; 14 km3 (3.4 cu mi) of lava, an estimated 120,000,000 t (130,000,000 short tons) of SO 2 were emitted, produced a Volcanic winter, 1783, on the North Hemisphere.
1452–53 New Hebrides arc, Vanuatu; the location of this eruption in the South Pacific is uncertain, as it has been identified from distant ice core records; the only pyroclastic flows are found at Kuwae; 36 to 96 km3 (8.6 to 23.0 cu mi) of tephra; 175,000,000–700,000,000 t (193,000,000–772,000,000 short tons) of sulfuric acid
1280(?) in Quilotoa, Ecuador; VEI 6; 21 km3 (5.0 cu mi) of tephra
This is a sortable summary of 27 major eruptions in the last 2000 years with VEI ≥6, implying an average of about 1.3 per century. The count does not include the notable VEI 5 eruptions of Mount St. Helens and Mount Vesuvius. Date uncertainties, tephra volumes, and references are also not included.
Caldera names tend to change over time. For example, Okataina Caldera, Haroharo Caldera, Haroharo volcanic complex, Tarawera volcanic complex had the same magma source in the Taupo Volcanic Zone. Yellowstone Caldera, Henry's Fork Caldera, Island Park Caldera, Heise Volcanic Field had all Yellowstone hotspot as magma source.
Lake Toba (size: 100 x 30 km), Sumatra, Indonesia; VEI 8; 73 ka ±4; 2,500 to 3,000 cubic kilometers (599.8 to 719.7 cu mi) of tephra; probably six gigatons of sulfur dioxide were emitted (Youngest Toba Tuff).
Atitlán Caldera (size: 17 x 20 km), Guatemalan Highlands; Los Chocoyos eruption; formed in an eruption 84 ka; VEI 7; 300 km3 (72 cu mi) of tephra.
Mount Aso (size: 24 km wide), island of Kyūshū, Japan; 90 ka; last eruption was more than 600 cubic kilometers (144 cu mi) of tephra.
Sierra La Primavera volcanic complex (size: 11 km wide), Guadalajara, Jalisco, Mexico; 95 ka; 20 cubic kilometers (5 cu mi) of Tala Tuff.
Mount Aso (size: 24 km wide), island of Kyūshū, Japan; 120 ka; 80 km3 (19 cu mi) of tephra.
Mount Aso (size: 24 km wide), island of Kyūshū, Japan; 140 ka; 80 km3 (19 cu mi) of tephra.
Puy de Sancy, Massif Central, central France; it is part of an ancient stratovolcano which has been inactive for about 220,000 years.
Emmons Lake Caldera (size: 11 x 18 km), Aleutian Range, 233 ka; more than 50 km3 (12 cu mi) of tephra.
Mount Aso (size: 24 km wide), island of Kyūshū, Japan; caldera formed as a result of four huge caldera eruptions; 270 ka; 80 cubic kilometers (19 cu mi) of tephra.
Tejeda Caldera, Gran Canaria, Spain; 13.9 Ma; the 80 km3 eruption produced a composite ignimbrite (P1) of rhyolite, trachyte and basaltic materials, with a thickness of 30 metres at 10 km from the caldera center
Gran Canaria shield basalt eruption, Spain; 14.5 to 14 Ma; 1,000 km3 of tholeiitic to alkali basalts
Campi Flegrei, Naples, Italy; 14.9 Ma; 79 cubic kilometers (19 cu mi) of Neapolitan Yellow Tuff.
Huaylillas Ignimbrite, Bolivia, southern Peru, northern Chile; 15 Ma ±1; 1,100 cubic kilometers (264 cu mi) of tephra.
Yellowstone hotspot, McDermitt volcanic field (North), Trout Creek Mountains, Whitehorse Caldera (size: 15 km wide), Oregon; 15 Ma; 40 cubic kilometers (10 cu mi) of Whitehorse Creek Tuff.
Yellowstone hotspot, McDermitt volcanic field (South), Jordan Meadow Caldera, (size: 10–15 km wide), Nevada/ Oregon; 15.6 Ma; 350 cubic kilometers (84 cu mi) Longridge Tuff member 2-3.
Yellowstone hotspot, McDermitt volcanic field (South), Longridge Caldera, (size: 33 km wide), Nevada/ Oregon; 15.6 Ma; 400 cubic kilometers (96 cu mi) Longridge Tuff member 5.
Yellowstone hotspot, McDermitt volcanic field (South), Calavera Caldera, (size: 17 km wide), Nevada/ Oregon; 15.7 Ma; 300 cubic kilometers (72 cu mi) of Double H Tuff.
Yellowstone hotspot, McDermitt volcanic field (South), Hoppin Peaks Caldera, 16 Ma; Hoppin Peaks Tuff.
Yellowstone hotspot, McDermitt volcanic field (North), Trout Creek Mountains, Pueblo Caldera (size: 20 x 10 km), Oregon; 15.8 Ma; 40 cubic kilometers (10 cu mi) of Trout Creek Mountains Tuff.
Yellowstone hotspot, McDermitt volcanic field (South), Washburn Caldera, (size: 30 x 25 km wide), Nevada/ Oregon; 16.548 Ma; 250 cubic kilometers (60 cu mi) of Oregon Canyon Tuff.
Yellowstone hotspot (?), Northwest Nevada volcanic field (NWNV), Virgin Valley, High Rock, Hog Ranch, and unnamed calderas; West of Pine Forest Range, Nevada; 15.5 to 16.5 Ma.
La Garita Caldera erupts in the Wheeler Geologic Area, Central Colorado volcanic field, Colorado, USA, eruption several VEI8 events (Possibly as high as a VEI9), 5,000 cubic kilometers (1,200 cu mi) of Fish Canyon Tuff was blasted out in a major single eruption about 27.8 million years ago.
Unknown source in Ethiopia erupts 29 million years ago with at least 3,000 cubic kilometers (720 cu mi) of Green Tuff and SAM.
Sam Ignimbrite in Yemen forms 29.5 million years ago, at least 5,550 cubic kilometers (1,332 cu mi) of distal tuffs associated with the ignimbrites.
Jabal Kura’a Ignimbrite in Yemen forms 29.6million years ago, at least 3,700 cubic kilometers (888 cu mi) of distal tuffs associated with the ignimbrites.
Paraná and Etendeka traps, Brazil, Namibia and Angola form 128 to 138 million years ago. 132 million years ago, a possible supervolcanic eruption occurred, ejecting 8,600 cubic kilometers (2,063 cu mi).
Formation of the Karoo-Ferrar flood basalts begins 183 million years ago.
Topographically visible calderas: South part of the McDermitt volcanic field (four overlapping and nested calderas), West of McDermitt; Cochetopa Park Caldera, West of the North Pass; Henry's Fork Caldera; Banks Peninsula, New Zealand (Photo) and Valles Caldera. Newer drawings show McDermitt volcanic field (South), as five overlapping and nested calderas. Hoppin Peaks Caldera is included too.
The global dimming through volcanism (ash aerosol and sulfur dioxide) is quite independent of the eruption VEI. When sulfur dioxide (boiling point at standard state: -10 °C) reacts with water vapor, it creates sulfate ions (the precursors to sulfuric acid), which are very reflective; ash aerosol on the other hand absorbs Ultraviolet. Global cooling through volcanism is the sum of the influence of the global dimming and the influence of the high albedo of the deposited ash layer. The lower snow line and its higher albedo might prolong this cooling period. Bipolar comparison showed six sulfate events: Tambora (1815), Cosigüina (1835), Krakatoa (1883), Agung (1963), and El Chichón (1982), and the 1808 mystery eruption. And the atmospheric transmission of direct solar radiation data from the Mauna Loa Observatory (MLO), Hawaii (19°32'N) detected only five eruptions:
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The 1465 mystery eruption was a large volcanic eruption conjectured to have taken place in 1465 or "the early 1460s". The location of this eruption is uncertain, as it has only been identified from distant ice core records and atmospheric events around the time of King Alfonso II of Naples's wedding in 1465; it is believed to have been VEI-7 and possibly even larger than Mount Tambora's 1815 eruption.
The Bennett Lake Volcanic Complex (BLVC) is a huge 50-million-year-old extinct caldera complex that spans across the British Columbia-Yukon border in Canada. It is located near the western end of the West Arm of Bennett Lake. The caldera complex is surrounded by granitic rocks containing pendants.
It is located near the eastern contact of the Coast Plutonic Complex and the Whitehorse Trough. There are thick series of pyroclastic and epiclastic rocks at the caldera. Remnants of this huge caldera complex are preserved near Bennett Lake in the Coast Mountains. The complex compose the Skukum Group.
Billy Mitchell is a volcano in the central part of the island of Bougainville, just north-east of the Bagana Volcano in Papua New Guinea. It is a small pyroclastic shield truncated by a 2 km wide caldera filled by a crater lake. It is named after Billy Mitchell, a 20th-century United States Army general who is regarded as the father of the United States Air Force.
The last two major eruptions were in 1580 AD ± 20 years and about 1030 AD. They were among the largest Holocene eruptions in Papua New Guinea. Both were explosive eruptions with a Volcanic Explosivity Index of at least 5. The 1580 AD ± 20 years eruption produced pyroclastic flows and probably formed its caldera. The ignimbrite deposit from that eruption, which had a VEI of 6, extends 22 kilometres (14 mi) from the caldera to the coast, and its volume is around 10 cubic kilometres (2.4 cu mi).
Bárðarbunga (Icelandic pronunciation: [ˈpaurðarpuŋka] (listen)), is a stratovolcano located under Vatnajökull, Iceland's most extensive glacier. The second highest mountain in Iceland, 2,009 metres (6,591 ft) above sea level, Bárðarbunga is also part of a volcanic system that is approximately 200 kilometres (120 mi) long and 25 kilometres (16 mi) wide.
The Decade Volcanoes are 16 volcanoes identified by the International Association of Volcanology and Chemistry of the Earth's Interior (IAVCEI) as being worthy of particular study in light of their history of large, destructive eruptions and proximity to populated areas. The Decade Volcanoes project encourages studies and public-awareness activities at these volcanoes, with the aim of achieving a better understanding of the volcanoes and the dangers they present, and thus being able to reduce the severity of natural disasters.
They are named Decade Volcanoes because the project was initiated in the 1990s as part of the United Nations-sponsored International Decade for Natural Disaster Reduction.
A volcano may be designated a Decade Volcano if it exhibits more than one volcanic hazard (people living near the Decade Volcanoes may experience tephra fall, pyroclastic flows, lava flows, lahars, volcanic edifice instability and lava dome collapse); shows recent geological activity; is located in a populated area (eruptions at any of the Decade Volcanoes may threaten tens or hundreds of thousands of people, and therefore mitigating eruption hazards at these volcanoes is crucial); is politically and physically accessible for study; and there is local support for the work.
The Smithsonian Institution's Global Volcanism Program (GVP) documents Earth's volcanoes and their eruptive history over the past 10,000 years. The GVP reports on current eruptions from around the world as well as maintaining a database repository on active volcanoes and their eruptions. In this way, a global context for the planet's active volcanism is presented. Smithsonian reporting on current volcanic activity dates back to 1968, with the Center for Short-Lived Phenomena (CSLP). The GVP is housed in the Department of Mineral Sciences, part of the National Museum of Natural History, on the National Mall in Washington, D.C.
During the early stages of an eruption, the GVP acts as a clearing house of reports, data, and imagery which are accumulated from a global network of contributors. The early flow of information is managed such that the right people are contacted as well as helping to sort out vague and contradictory aspects that typically arise during the early days of an eruption.
The Weekly Volcanic Activity Report is a cooperative project between the Smithsonian's Global Volcanism Program and the United States Geological Survey's Volcano Hazards Program. Notices of volcanic activity posted on the report website are preliminary and subject to change as events are studied in more detail. Detailed reports on various volcanoes are published monthly in the Bulletin of the Global Volcanism NetworkThe GVP also documents the last 10,000 years of Earth's volcanism. The historic activity can guide perspectives on possible future events and on volcanoes showing activity. GVP's volcano and eruption databases constitute a foundation for all statistical statements concerning locations, frequencies, and magnitudes of Earth's volcanic eruptions during the past recent 10,000 years.
Two editions of Volcanoes of the World, a regional directory... (1981) and (1994) were published based on the GVP data and interpretations.
Kolumbo is an active submarine volcano in the Aegean Sea, about 8 km northeast of Cape Kolumbo, Santorini island. The largest of a line of about twenty submarine volcanic cones extending to the northeast from Santorini, it is about 3 km in diameter with a crater 1.5 km across. It was "discovered" when it breached the sea surface in 1649-50, but its explosion was not to be compared to the well-known Thera explosion and caldera collapse, currently dated ca. 1630 BCE, with its devastating consequences for Minoan civilization. The Smithsonian Institution's Global Volcanism Program treats it as part of the Santorini volcano.The 1650 explosion, which occurred when the accumulating cone reached the surface, sent pyroclastic flows across the sea surface to the shores and slopes of Santorini, where about seventy people and many animals died. A small ring of white pumice that formed was rapidly eroded away by wave action. The volcano collapsed into its caldera, triggering a tsunami that caused damage on nearby islands up to 150 km distant. The highest parts of the crater rim are now about 10 m below sea level.
In 2006, sea floor pyroclastic deposits from the two Aegean explosions were explored, sampled and mapped by an expedition by NOAA Ocean Explorer, equipped with ROV robotics.
The crater floor, averaging about 505 m below the sea surface, is marked in its northeast area by a field of hydrothermal vents and covered by a thick bacterial community, the 2006 NOAA expedition discovered. Superheated (measured as hot as 224 °C) metal-enriched water issuing from the vents has built chimneys of polymetallic sulfide/sulfates to a maximum height of 4 m, apparently accumulated since the 1650 event.
The 2006 expedition initiated new seismic air-gun techniques in order to determine the volume and distribution of the submarine volcanic deposit of pumice and ash on the sea floor around Santorini, which has been studied extensively since 1975. Revised, more accurate estimates of the total dense rock equivalent volume of the Minoan event(s), consisting of pyroclastic sea floor deposits, distal ash fallout and ignimbrites on the island of Santorini, is likely about 60 km³, a greatly increased estimate, comparable to the largest historic explosion, Mount Tambora 1815; the increased estimate affects the size of the ensuing tsunami as it has been widely modeled.
This is a sortable summary of the pages Timeline of volcanism on Earth, List of Quaternary volcanic eruptions, and Large volume volcanic eruptions in the Basin and Range Province. Uncertainties as to dates and tephra volumes are not restated, and references are not repeated. Volcanic Explosivity Index (VEI) values for events in the Miocene epoch sometimes lack references. They are given as VEI-equivalent, as orientation of the erupted tephra volume. Please note that this is not a comprehensive list, and some events are missing from the table.
Novarupta (meaning "newly erupted" in Latin) is a volcano that was formed in 1912, located on the Alaska Peninsula in Katmai National Park and Preserve, about 290 miles (470 km) southwest of Anchorage. Formed during the largest volcanic eruption of the 20th century, Novarupta released 30 times the volume of magma of the 1980 eruption of Mount St. Helens.
Santa María Volcano is a large active volcano in the western highlands of Guatemala, in the Quetzaltenango Department near the city of Quetzaltenango.
The volcano was known as Gagxanul in the local K'iche' language, before the 16th century Spanish conquest of the region.The VEI-6 eruption of Santa María Volcano in 1902 was one of the three largest eruptions of the 20th century, after the 1912 Novarupta and 1991 Mount Pinatubo eruptions. It is also one of the five biggest eruptions of the past 200 (and most likely 300) years.
A supervolcano is a large volcano that has had an eruption with a Volcanic Explosivity Index (VEI) of 8, the largest recorded value on the index. This means the volume of deposits for that eruption is greater than 1,000 cubic kilometers (240 cubic miles).
Supervolcanoes occur when magma in the mantle rises into the crust but is unable to break through it and pressure builds in a large and growing magma pool until the crust is unable to contain the pressure. This can occur at hotspots (for example, Yellowstone Caldera) or at subduction zones (for example, Toba). Large-volume supervolcanic eruptions are also often associated with large igneous provinces, which can cover huge areas with lava and volcanic ash. These can cause long-lasting climate change (such as the triggering of a small ice age) and threaten species with extinction. The Oruanui eruption of New Zealand's Taupo Volcano (about 26,500 years ago) was the world's most recent VEI-8 eruption.
The Toba supereruption was a supervolcanic eruption that occurred about 75,000 years ago at the site of present-day Lake Toba in Sumatra, Indonesia. It is one of the Earth's largest known eruptions. The Toba catastrophe theory holds that this event caused a global volcanic winter of six to ten years and possibly a 1,000-year-long cooling episode.
In 1993, science journalist Ann Gibbons posited that a population bottleneck occurred in human evolution about 70,000 years ago, and she suggested that this was caused by the eruption. Geologist Michael R. Rampino of New York University and volcanologist Stephen Self of the University of Hawaii at Manoa support her suggestion. In 1998, the bottleneck theory was further developed by anthropologist Stanley H. Ambrose of the University of Illinois at Urbana–Champaign. Both the link and global winter theories are highly controversial.
The Toba event is the most closely studied supereruption.
The Volcanic Explosivity Index (VEI) is a relative measure of the explosiveness of volcanic eruptions. It was devised by Chris Newhall of the United States Geological Survey and Stephen Self at the University of Hawaii in 1982.
Volume of products, eruption cloud height, and qualitative observations (using terms ranging from "gentle" to "mega-colossal") are used to determine the explosivity value. The scale is open-ended with the largest volcanoes in history given magnitude 8. A value of 0 is given for non-explosive eruptions, defined as less than 10,000 m3 (350,000 cu ft) of tephra ejected; and 8 representing a mega-colossal explosive eruption that can eject 1.0×1012 m3 (240 cubic miles) of tephra and have a cloud column height of over 20 km (66,000 ft). The scale is logarithmic, with each interval on the scale representing a tenfold increase in observed ejecta criteria, with the exception of between VEI-0, VEI-1 and VEI-2.
A volcanic winter is a reduction in global temperatures caused by volcanic ash and droplets of sulfuric acid and water obscuring the Sun and raising Earth's albedo (increasing the reflection of solar radiation) after a large, particularly explosive volcanic eruption. Long-term cooling effects are primarily dependent upon injection of sulfur gasses into the stratosphere where they undergo a series of reactions to create sulfuric acid which can nucleate and form aerosols. Volcanic stratospheric aerosols cool the surface by reflecting solar radiation and warm the stratosphere by absorbing terrestrial radiation. The variations in atmospheric warming and cooling result in changes in tropospheric and stratospheric circulation.
Volcanoes of the World was a book that was published in three editions in 1981, 1994, and 2010 as a collaboration between volcanologists around the world, and the Smithsonian Institution's Global Volcanism Program (GVP).
The year 1816 is known as the Year Without a Summer (also the Poverty Year and Eighteen Hundred and Froze To Death) because of severe climate abnormalities that caused average global temperatures to decrease by 0.4–0.7 °C (0.72–1.26 °F). This resulted in major food shortages across the Northern Hemisphere.Evidence suggests that the anomaly was predominantly a volcanic winter event caused by the massive 1815 eruption of Mount Tambora in April in the Dutch East Indies (now Indonesia). This eruption was the largest eruption in at least 1,300 years (after the extreme weather events of 535–536), and perhaps exacerbated by the 1814 eruption of Mayon in the Philippines.
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