Eyjafjallajökull
Encyclopedia
Eyjafjallajökull is one of the smaller ice cap
s of Iceland
, situated to the north of Skógar
and to the west of Mýrdalsjökull
. The ice cap
covers the caldera
of a volcano
with a summit elevation of 1666 metres (5,465.9 ft). The volcano has erupted relatively frequently since the last glacial period, most recently in 2010
.
The mountain itself, a stratovolcano
, stands 1651 metres (5,416.7 ft) at it highest point, and has a crater
3 – in diameter, open to the north. The crater rim has three main peaks, being (clockwise from the north-east) Guðnasteinn, 1500 metres (4,921.3 ft) (approx), Hámundur, 1651 metres (5,416.7 ft) and Goðasteinn, 1497 metres (4,911.4 ft). The south face of the mountain was once part of Iceland's Atlantic coastline, from which, over thousands of years, the sea has retreated some 5 kilometres (3.1 mi). The former coastline now consists of sheer cliffs with many waterfall
s, of which the best known is Skógafoss
. In strong winds, the water of the smaller falls can even be blown up the mountain. The area between the mountain and the present coast is a relatively flat strand, 2 to 5 km wide, called Eyjafjöll.
The volcano is fed by a magma chamber
under the mountain, which in turn derives from the tectonic
divergence
of the Mid-Atlantic Ridge
. It is part of a chain of volcanoes stretching across Iceland. Its nearest active neighbours are Katla, to the northeast, and Eldfell
, on Heimaey
, to the southwest.
The volcano is thought to be related to Katla geologically, in that eruptions of Eyjafjallajökull have generally been followed by eruptions of Katla.
The Eyjafjallajökull volcano erupted in 920, 1612 and again from 1821 to 1823 when it caused a glacial lake outburst flood
or jökulhlaup
. It erupted twice in 2010
— on 20 March and in April/May. The March event forced a brief evacuation of around 500 local people, but the 14 April eruption was ten to twenty times more powerful and caused substantial disruption to air traffic
across Europe
. It caused the cancellation of thousands of flights across and to Iceland.
", (or more properly here "ice cap
"), of the Eyjafjöll. The word jökull, meaning glacier of ice cap, is cognate with the Middle English
word ikel surviving in the -icle of English icicle).
Eyjafjöll is the name given to the southern side of the volcanic massif together with the small mountains which form the foot of the volcano.
The name Eyjafjöll is made up of the words eyja (genitive plural of ey, meaning eyot or island), and the plural word fjöll, meaning fells or mountains), and together literally means: "the mountains of the islands". The name probably refers to the close-by archipelago of Vestmannaeyjar.
The word fjalla is the genitive plural of fjöll, and so Eyjafjalla is the genitive form of Eyjafjöll and means: "of the Eyjafjöll".
A literal part-by-part translation of Eyjafjallajökull would thus be "Islands' Mountains' ice cap".
, whose vents follow an east-west trend, is composed of basalt
to andesite
lava
s. Most of its historical eruptions have been explosive
. However, fissure vent
s occur on both (mainly the west) sides of the volcano.
, which in high doses may harm the bone structure of cattle, horses, sheep and humans. The eruption also caused some small and medium glacier runs and flooding in nearby rivers Markarfljót
and Holtsá. The eruptive phase started on 19 and 20 December 1821 by a series of explosive eruptions and continued over the next several days. The sources describe heavy ash fall in the area around the volcano, especially to the south and west.
After that event the sequence of eruptions continued on a more subdued level until June 1822.
From the end of June until the beginning of August 1822, another sequence of explosive eruptions followed. The eruption columns were shot to considerable heights, with ashfall in both the far north of the country, in Eyjafjörður
, and in the southwest, on the peninsula of Seltjarnarnes
near Reykjavík
.
The period from August to December 1822 seemed quieter, but farmers attributed the death of cattle and sheep in the Eyjafjörður area to poisoning from this eruption, which modern analysis identifies as fluoride poisoning
. Some small glacier runs occurred in the river Holtsá. A bigger one flooded the plains near the river Markarfljót. The sources don’t indicate the exact date.
In 1823, some men went hiking up on Eyjafjallajökull to inspect the craters
. They discovered a fissure vent
near the summit caldera
a bit to the west of Guðnasteinn.
In early 1823, the nearby volcano Katla under the Mýrdalsjökull
ice cap erupted and at the same time steam columns were seen on the summit of Eyjafjallajökull.
The ash of Eyjafjallajökull’s 1821 eruptions is to be found all over the south of Iceland. It is dark grey in colour, small-grained and intermediate rock containing about 28–40% silicon dioxide
.
s (mostly magnitude 1–2 on the Richter magnitude scale
, with only a couple greater than 3 magnitude) 7 – beneath the volcano. On 26 February 2010, unusual seismic activity along with rapid expansion of the Earth's crust was registered by the Meteorological Institute of Iceland. This gave geophysicists evidence that magma was pouring from underneath the crust into the magma chamber
of the Eyjafjallajökull volcano and that pressure stemming from the process caused the huge crustal displacement at Þorvaldseyri farm. The seismic activity continued to increase and from 3–5 March, close to 3,000 earthquakes were measured at the epicentre of the volcano.
The eruption is thought to have begun on 20 March 2010, about 8 kilometres (5 mi) east of the top crater of the volcano, on Fimmvörðuháls
, the high neck between Eyjafjallajökull and the neighboring icecap, Mýrdalsjökull. This first eruption, in the form of a fissure vent
, did not occur under the glacier and was smaller in scale than had been expected by some geologists. The fissure opened on the north side of Fimmvörðuháls, directly across the popular hiking trail between Skógar, south of the pass, and Þórsmörk
, immediately to the north.
On 14 April 2010 Eyjafjallajökull resumed erupting after a brief pause, this time from the top crater in the centre of the glacier, causing meltwater
flood
s (also known as jökulhlaup
) to rush down the nearby rivers, and requiring 800 people to be evacuated. This eruption was explosive in nature, due to melt water getting into the volcanic vent. It is estimated to be ten to twenty times larger than the previous one in Fimmvörðuháls
. This second eruption threw volcanic ash several kilometres up in the atmosphere which led to air travel disruption
in northwest Europe for six days from 15 April to 21 of April and also in May 2010, including the closure of airspace
over many parts of Europe. The eruptions also created electrical storms
. On 23 May 2010, the London Volcanic Ash Advisory Commission declared the eruption to have stopped, but are continuing to monitor the volcano. The volcano continues to have several earthquakes daily, with Volcanologists watching the volcano closely. Only when activity has ceased for three months will it be considered dormant.
ice cap, which is much more active and known for its powerful subglacial eruption
s and its large magma chamber. Each of the eruptions of Eyjafjallajökull in 920, 1612, and 1821–1823 has preceded an eruption of Katla. Katla has not displayed any unusual activity (such as expansion of the crust or seismic activity) during the 2010 eruptions of Eyjafjallajökull, though geologists have been concerned about the general instability of Katla since 1999. Some geophysicists in Iceland believe that the Eyjafjallajökull eruption may trigger an eruption of Katla, which would cause major flooding due to melting of glacial ice and send up massive plumes of ash. On 20 April 2010 Icelandic President Ólafur Grímsson
said "the time for Katla to erupt is coming close...we [Iceland] have prepared...it is high time for European governments and airline authorities all over the world to start planning for the eventual Katla eruption".
Volcanologists continue to monitor Katla, aware that any eruption from Katla following an eruption from Eyjafjallajökull has historically occurred within months of an Eyjafjallajökull eruption. The Icelandic Meteorological Office updates its website with reports of quakes both at Eyjafjallajökull and Katla.
Videos and webcams
Audio
Geological articles
Aviation ash forecasts
Maps
Ice cap
An ice cap is an ice mass that covers less than 50 000 km² of land area . Masses of ice covering more than 50 000 km² are termed an ice sheet....
s of Iceland
Iceland
Iceland , described as the Republic of Iceland, is a Nordic and European island country in the North Atlantic Ocean, on the Mid-Atlantic Ridge. Iceland also refers to the main island of the country, which contains almost all the population and almost all the land area. The country has a population...
, situated to the north of Skógar
Skógar
Skógar , literally forests, is a small Icelandic village with a population of roughly 25 located at the south of the Eyjafjallajökull glacier, in the municipality of Rangárþing eystra....
and to the west of Mýrdalsjökull
Mýrdalsjökull
Mýrdalsjökull mire dale glacier" or " mire valley glacier") is a glacier in the south of Iceland. It is situated to the north of Vík í Mýrdal and to the east of the smaller glacier Eyjafjallajökull. Between these two glaciers is Fimmvörðuháls pass. Its peak reaches in height and in 1980 it covered...
. The ice cap
Ice cap
An ice cap is an ice mass that covers less than 50 000 km² of land area . Masses of ice covering more than 50 000 km² are termed an ice sheet....
covers the caldera
Caldera
A caldera is a cauldron-like volcanic feature usually formed by the collapse of land following a volcanic eruption, such as the one at Yellowstone National Park in the US. They are sometimes confused with volcanic craters...
of a volcano
Volcano
2. Bedrock3. Conduit 4. Base5. Sill6. Dike7. Layers of ash emitted by the volcano8. Flank| 9. Layers of lava emitted by the volcano10. Throat11. Parasitic cone12. Lava flow13. Vent14. Crater15...
with a summit elevation of 1666 metres (5,465.9 ft). The volcano has erupted relatively frequently since the last glacial period, most recently in 2010
2010 eruptions of Eyjafjallajökull
The 2010 eruptions of Eyjafjallajökull were volcanic events at Eyjafjöll in Iceland which, although relatively small for volcanic eruptions, caused enormous disruption to air travel across western and northern Europe over an initial period of six days in April 2010. Additional localised disruption...
.
Geography
Eyjafjallajökull consists of a volcano completely covered by an ice cap. The ice cap covers an area of about 100 square kilometres (38.6 sq mi), feeding many outlet glaciers. The main outlet glaciers are to the north; Gígjökull, flowing into Lónið, and Steinholtsjökull, flowing into Steinholtslón. The glacier is the 6th largest in Iceland. In 1967 there was a massive landslide on the Steinholtsjökull glacial tongue. On January 15, 1967 at 13.47.55 there was an explosion on the glacier. It can be timed because the earthquake meters in Kirkjubæjarklaustur monitored the movement. When about 15 million cubic meters of material hit the glacier a massive amount of air, ice, and water began to move from under the glacier out into the lagoon at the foot of the glacier.The mountain itself, a stratovolcano
Stratovolcano
A stratovolcano, also known as a composite volcano, is a tall, conical volcano built up by many layers of hardened lava, tephra, pumice, and volcanic ash. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile and periodic, explosive eruptions...
, stands 1651 metres (5,416.7 ft) at it highest point, and has a crater
Volcanic crater
A volcanic crater is a circular depression in the ground caused by volcanic activity. It is typically a basin, circular in form within which occurs a vent from which magma erupts as gases, lava, and ejecta. A crater can be of large dimensions, and sometimes of great depth...
3 – in diameter, open to the north. The crater rim has three main peaks, being (clockwise from the north-east) Guðnasteinn, 1500 metres (4,921.3 ft) (approx), Hámundur, 1651 metres (5,416.7 ft) and Goðasteinn, 1497 metres (4,911.4 ft). The south face of the mountain was once part of Iceland's Atlantic coastline, from which, over thousands of years, the sea has retreated some 5 kilometres (3.1 mi). The former coastline now consists of sheer cliffs with many waterfall
Waterfall
A waterfall is a place where flowing water rapidly drops in elevation as it flows over a steep region or a cliff.-Formation:Waterfalls are commonly formed when a river is young. At these times the channel is often narrow and deep. When the river courses over resistant bedrock, erosion happens...
s, of which the best known is Skógafoss
Skógafoss
Skógafoss is a waterfall situated in the south of Iceland at the cliffs of the former coastline. After the coastline had receded seaward , the former sea cliffs remained, parallel to the coast over hundreds of kilometres, creating together with some mountains a clear border between the coastal...
. In strong winds, the water of the smaller falls can even be blown up the mountain. The area between the mountain and the present coast is a relatively flat strand, 2 to 5 km wide, called Eyjafjöll.
The volcano is fed by a magma chamber
Magma chamber
A magma chamber is a large underground pool of molten rock found beneath the surface of the Earth. The molten rock in such a chamber is under great pressure, and given enough time, that pressure can gradually fracture the rock around it creating outlets for the magma...
under the mountain, which in turn derives from the tectonic
Plate tectonics
Plate tectonics is a scientific theory that describes the large scale motions of Earth's lithosphere...
divergence
Divergent boundary
In plate tectonics, a divergent boundary or divergent plate boundary is a linear feature that exists between two tectonic plates that are moving away from each other. Divergent boundaries within continents initially produce rifts which produce rift valleys...
of the Mid-Atlantic Ridge
Mid-Atlantic Ridge
The Mid-Atlantic Ridge is a mid-ocean ridge, a divergent tectonic plate boundary located along the floor of the Atlantic Ocean, and part of the longest mountain range in the world. It separates the Eurasian Plate and North American Plate in the North Atlantic, and the African Plate from the South...
. It is part of a chain of volcanoes stretching across Iceland. Its nearest active neighbours are Katla, to the northeast, and Eldfell
Eldfell
Eldfell is a composite volcanic cone just over high on the Icelandic island of Heimaey. It formed in a volcanic eruption which began without warning just outside the town of Heimaey on 23 January 1973. Its name means Mountain of Fire in Icelandic....
, on Heimaey
Heimaey
Heimaey , literally Home Island, is an Icelandic island. At a size of 13.4 km² , it is the largest island in the Vestmannaeyjar archipelago, and the largest and most populated Icelandic island outside the main island of Iceland. Heimaey lies approximately 4 nautical miles off the south coast...
, to the southwest.
The volcano is thought to be related to Katla geologically, in that eruptions of Eyjafjallajökull have generally been followed by eruptions of Katla.
The Eyjafjallajökull volcano erupted in 920, 1612 and again from 1821 to 1823 when it caused a glacial lake outburst flood
Glacial lake outburst flood
A glacial lake outburst flood is a type of outburst flood that occurs when the dam containing a glacial lake fails. The dam can consist of glacier ice or a terminal moraine...
or jökulhlaup
Jökulhlaup
A jökulhlaup is a glacial outburst flood. It is an Icelandic term that has been adopted by the English language. It originally referred to the well-known subglacial outburst floods from Vatnajökull, Iceland which are triggered by geothermal heating and occasionally by a volcanic subglacial...
. It erupted twice in 2010
2010 eruptions of Eyjafjallajökull
The 2010 eruptions of Eyjafjallajökull were volcanic events at Eyjafjöll in Iceland which, although relatively small for volcanic eruptions, caused enormous disruption to air travel across western and northern Europe over an initial period of six days in April 2010. Additional localised disruption...
— on 20 March and in April/May. The March event forced a brief evacuation of around 500 local people, but the 14 April eruption was ten to twenty times more powerful and caused substantial disruption to air traffic
Air travel disruption after the 2010 Eyjafjallajökull eruption
In response to concerns that volcanic ash ejected during the 2010 eruptions of Eyjafjallajökull in Iceland would damage aircraft engines, the controlled airspace of many European countries was closed to instrument flight rules traffic, resulting in the largest air-traffic shut-down since World War II...
across Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
. It caused the cancellation of thousands of flights across and to Iceland.
Etymology
The name means "glacierGlacier
A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...
", (or more properly here "ice cap
Ice cap
An ice cap is an ice mass that covers less than 50 000 km² of land area . Masses of ice covering more than 50 000 km² are termed an ice sheet....
"), of the Eyjafjöll. The word jökull, meaning glacier of ice cap, is cognate with the Middle English
Middle English
Middle English is the stage in the history of the English language during the High and Late Middle Ages, or roughly during the four centuries between the late 11th and the late 15th century....
word ikel surviving in the -icle of English icicle).
Eyjafjöll is the name given to the southern side of the volcanic massif together with the small mountains which form the foot of the volcano.
The name Eyjafjöll is made up of the words eyja (genitive plural of ey, meaning eyot or island), and the plural word fjöll, meaning fells or mountains), and together literally means: "the mountains of the islands". The name probably refers to the close-by archipelago of Vestmannaeyjar.
The word fjalla is the genitive plural of fjöll, and so Eyjafjalla is the genitive form of Eyjafjöll and means: "of the Eyjafjöll".
A literal part-by-part translation of Eyjafjallajökull would thus be "Islands' Mountains' ice cap".
Geology
The stratovolcanoStratovolcano
A stratovolcano, also known as a composite volcano, is a tall, conical volcano built up by many layers of hardened lava, tephra, pumice, and volcanic ash. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile and periodic, explosive eruptions...
, whose vents follow an east-west trend, is composed of basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...
to andesite
Andesite
Andesite is an extrusive igneous, volcanic rock, of intermediate composition, with aphanitic to porphyritic texture. In a general sense, it is the intermediate type between basalt and dacite. The mineral assemblage is typically dominated by plagioclase plus pyroxene and/or hornblende. Magnetite,...
lava
Lava
Lava refers both to molten rock expelled by a volcano during an eruption and the resulting rock after solidification and cooling. This molten rock is formed in the interior of some planets, including Earth, and some of their satellites. When first erupted from a volcanic vent, lava is a liquid at...
s. Most of its historical eruptions have been explosive
Explosive eruption
An explosive eruption is a volcanic term to describe a violent, explosive type of eruption. Mount St. Helens in 1980 was an example. Such an eruption is driven by gas accumulating under great pressure. Driven by hot rising magma, it interacts with ground water until the pressure increases to the...
. However, fissure vent
Fissure vent
A fissure vent, also known as a volcanic fissure or simply fissure, is a linear volcanic vent through which lava erupts, usually without any explosive activity. The vent is usually a few meters wide and may be many kilometers long. Fissure vents can cause large flood basalts and lava channels...
s occur on both (mainly the west) sides of the volcano.
1821 to 1823 eruptions
Some damage was caused by a minor eruption in 1821. Notably, the ash released from the eruption contained a large fraction of fluorideFluoride
Fluoride is the anion F−, the reduced form of fluorine when as an ion and when bonded to another element. Both organofluorine compounds and inorganic fluorine containing compounds are called fluorides. Fluoride, like other halides, is a monovalent ion . Its compounds often have properties that are...
, which in high doses may harm the bone structure of cattle, horses, sheep and humans. The eruption also caused some small and medium glacier runs and flooding in nearby rivers Markarfljót
Markarfljót
Markarfljót is a river in the south of Iceland. It is approximately 100 kilometers long.The Markarfljót rises in the Rauðafossafjöll massif, east of the volcano Hekla. The main sources for the river are the glaciers Mýrdalsjökull and Eyjafjallajökull...
and Holtsá. The eruptive phase started on 19 and 20 December 1821 by a series of explosive eruptions and continued over the next several days. The sources describe heavy ash fall in the area around the volcano, especially to the south and west.
After that event the sequence of eruptions continued on a more subdued level until June 1822.
From the end of June until the beginning of August 1822, another sequence of explosive eruptions followed. The eruption columns were shot to considerable heights, with ashfall in both the far north of the country, in Eyjafjörður
Eyjafjörður
Eyjafjörður is the longest fjord in central northern Iceland. It is located in the second most populous region of Iceland.-Physical geography:...
, and in the southwest, on the peninsula of Seltjarnarnes
Seltjarnarnes
Seltjarnarnes is an Icelandic township located within the Greater Reykjavík area.It took on its current political form shortly after the Second World War and was formally created as a township in 1947. It is the smallest Icelandic township by land ....
near Reykjavík
Reykjavík
Reykjavík is the capital and largest city in Iceland.Its latitude at 64°08' N makes it the world's northernmost capital of a sovereign state. It is located in southwestern Iceland, on the southern shore of Faxaflói Bay...
.
The period from August to December 1822 seemed quieter, but farmers attributed the death of cattle and sheep in the Eyjafjörður area to poisoning from this eruption, which modern analysis identifies as fluoride poisoning
Fluoride poisoning
In high concentrations, soluble fluoride salts are toxic and skin or eye contact with high concentrations of many fluoride salts is dangerous. Referring to a common salt of fluoride, sodium fluoride , the lethal dose for most adult humans is estimated at 5 to 10 g...
. Some small glacier runs occurred in the river Holtsá. A bigger one flooded the plains near the river Markarfljót. The sources don’t indicate the exact date.
In 1823, some men went hiking up on Eyjafjallajökull to inspect the craters
Volcanic crater
A volcanic crater is a circular depression in the ground caused by volcanic activity. It is typically a basin, circular in form within which occurs a vent from which magma erupts as gases, lava, and ejecta. A crater can be of large dimensions, and sometimes of great depth...
. They discovered a fissure vent
Fissure vent
A fissure vent, also known as a volcanic fissure or simply fissure, is a linear volcanic vent through which lava erupts, usually without any explosive activity. The vent is usually a few meters wide and may be many kilometers long. Fissure vents can cause large flood basalts and lava channels...
near the summit caldera
Caldera
A caldera is a cauldron-like volcanic feature usually formed by the collapse of land following a volcanic eruption, such as the one at Yellowstone National Park in the US. They are sometimes confused with volcanic craters...
a bit to the west of Guðnasteinn.
In early 1823, the nearby volcano Katla under the Mýrdalsjökull
Mýrdalsjökull
Mýrdalsjökull mire dale glacier" or " mire valley glacier") is a glacier in the south of Iceland. It is situated to the north of Vík í Mýrdal and to the east of the smaller glacier Eyjafjallajökull. Between these two glaciers is Fimmvörðuháls pass. Its peak reaches in height and in 1980 it covered...
ice cap erupted and at the same time steam columns were seen on the summit of Eyjafjallajökull.
The ash of Eyjafjallajökull’s 1821 eruptions is to be found all over the south of Iceland. It is dark grey in colour, small-grained and intermediate rock containing about 28–40% silicon dioxide
Silicon dioxide
The chemical compound silicon dioxide, also known as silica , is an oxide of silicon with the chemical formula '. It has been known for its hardness since antiquity...
.
2010 eruptions
Around December 2009, seismic activity was detected in the volcano area, with thousands of small earthquakeEarthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
s (mostly magnitude 1–2 on the Richter magnitude scale
Richter magnitude scale
The expression Richter magnitude scale refers to a number of ways to assign a single number to quantify the energy contained in an earthquake....
, with only a couple greater than 3 magnitude) 7 – beneath the volcano. On 26 February 2010, unusual seismic activity along with rapid expansion of the Earth's crust was registered by the Meteorological Institute of Iceland. This gave geophysicists evidence that magma was pouring from underneath the crust into the magma chamber
Magma chamber
A magma chamber is a large underground pool of molten rock found beneath the surface of the Earth. The molten rock in such a chamber is under great pressure, and given enough time, that pressure can gradually fracture the rock around it creating outlets for the magma...
of the Eyjafjallajökull volcano and that pressure stemming from the process caused the huge crustal displacement at Þorvaldseyri farm. The seismic activity continued to increase and from 3–5 March, close to 3,000 earthquakes were measured at the epicentre of the volcano.
The eruption is thought to have begun on 20 March 2010, about 8 kilometres (5 mi) east of the top crater of the volcano, on Fimmvörðuháls
Fimmvörðuháls
Fimmvörðuháls is the area between the glaciers Eyjafjallajökull and Mýrdalsjökull in southern Iceland. The route between Skógar and Thórsmörk goes through this pass and is one of the most popular walking routes in Iceland, despite being 22 km long and involving 1,000 m of climbing...
, the high neck between Eyjafjallajökull and the neighboring icecap, Mýrdalsjökull. This first eruption, in the form of a fissure vent
Fissure vent
A fissure vent, also known as a volcanic fissure or simply fissure, is a linear volcanic vent through which lava erupts, usually without any explosive activity. The vent is usually a few meters wide and may be many kilometers long. Fissure vents can cause large flood basalts and lava channels...
, did not occur under the glacier and was smaller in scale than had been expected by some geologists. The fissure opened on the north side of Fimmvörðuháls, directly across the popular hiking trail between Skógar, south of the pass, and Þórsmörk
Þórsmörk
Thórsmörk is a mountain ridge in Iceland that was named after the Norse god Thor . It is situated in the south of Iceland between the glaciers Tindfjallajökull and Eyjafjallajökull...
, immediately to the north.
On 14 April 2010 Eyjafjallajökull resumed erupting after a brief pause, this time from the top crater in the centre of the glacier, causing meltwater
Meltwater
Meltwater is the water released by the melting of snow or ice, including glacial ice and ice shelfs over oceans. Meltwater is often found in the ablation zone of glaciers, where the rate of snow cover is reducing...
flood
Flood
A flood is an overflow of an expanse of water that submerges land. The EU Floods directive defines a flood as a temporary covering by water of land not normally covered by water...
s (also known as jökulhlaup
Jökulhlaup
A jökulhlaup is a glacial outburst flood. It is an Icelandic term that has been adopted by the English language. It originally referred to the well-known subglacial outburst floods from Vatnajökull, Iceland which are triggered by geothermal heating and occasionally by a volcanic subglacial...
) to rush down the nearby rivers, and requiring 800 people to be evacuated. This eruption was explosive in nature, due to melt water getting into the volcanic vent. It is estimated to be ten to twenty times larger than the previous one in Fimmvörðuháls
Fimmvörðuháls
Fimmvörðuháls is the area between the glaciers Eyjafjallajökull and Mýrdalsjökull in southern Iceland. The route between Skógar and Thórsmörk goes through this pass and is one of the most popular walking routes in Iceland, despite being 22 km long and involving 1,000 m of climbing...
. This second eruption threw volcanic ash several kilometres up in the atmosphere which led to air travel disruption
Air travel disruption after the 2010 Eyjafjallajökull eruption
In response to concerns that volcanic ash ejected during the 2010 eruptions of Eyjafjallajökull in Iceland would damage aircraft engines, the controlled airspace of many European countries was closed to instrument flight rules traffic, resulting in the largest air-traffic shut-down since World War II...
in northwest Europe for six days from 15 April to 21 of April and also in May 2010, including the closure of airspace
Airspace
Airspace means the portion of the atmosphere controlled by a country above its territory, including its territorial waters or, more generally, any specific three-dimensional portion of the atmosphere....
over many parts of Europe. The eruptions also created electrical storms
Dirty thunderstorm
A dirty thunderstorm is a weather phenomenon that occurs when lightning is produced in a volcanic plume.A famous image of the phenomenon was photographed by Carlos Gutierrez and occurred in Chile above the Chaiten Volcano. It circulated widely on the internet...
. On 23 May 2010, the London Volcanic Ash Advisory Commission declared the eruption to have stopped, but are continuing to monitor the volcano. The volcano continues to have several earthquakes daily, with Volcanologists watching the volcano closely. Only when activity has ceased for three months will it be considered dormant.
Eyjafjallajökull and Katla
Eyjafjallajökull lies 25 km west of another subglacial volcano, Katla, under the MýrdalsjökullMýrdalsjökull
Mýrdalsjökull mire dale glacier" or " mire valley glacier") is a glacier in the south of Iceland. It is situated to the north of Vík í Mýrdal and to the east of the smaller glacier Eyjafjallajökull. Between these two glaciers is Fimmvörðuháls pass. Its peak reaches in height and in 1980 it covered...
ice cap, which is much more active and known for its powerful subglacial eruption
Subglacial eruption
A subglacial eruption is a volcanic eruption that has occurred under ice, or under a glacier. Subglacial eruptions can cause dangerous floods, lahars and create hyaloclastite and pillow lava. Subglacial eruptions sometimes form a subglacial volcano called a tuya. Tuyas in Iceland are called table...
s and its large magma chamber. Each of the eruptions of Eyjafjallajökull in 920, 1612, and 1821–1823 has preceded an eruption of Katla. Katla has not displayed any unusual activity (such as expansion of the crust or seismic activity) during the 2010 eruptions of Eyjafjallajökull, though geologists have been concerned about the general instability of Katla since 1999. Some geophysicists in Iceland believe that the Eyjafjallajökull eruption may trigger an eruption of Katla, which would cause major flooding due to melting of glacial ice and send up massive plumes of ash. On 20 April 2010 Icelandic President Ólafur Grímsson
Ólafur Ragnar Grímsson
Ólafur Ragnar Grímsson is the fifth and current President of Iceland. He has served as President since 1996; he was unopposed in 2000, re-elected for a third term in 2004, and re-elected unopposed for a fourth term in 2008. He is the longest-serving left-wing president in the history of...
said "the time for Katla to erupt is coming close...we [Iceland] have prepared...it is high time for European governments and airline authorities all over the world to start planning for the eventual Katla eruption".
Volcanologists continue to monitor Katla, aware that any eruption from Katla following an eruption from Eyjafjallajökull has historically occurred within months of an Eyjafjallajökull eruption. The Icelandic Meteorological Office updates its website with reports of quakes both at Eyjafjallajökull and Katla.
See also
- Glaciers of IcelandGlaciers of IcelandThe glaciers and ice caps of Iceland cover 11.1% of the land area of the country and have a considerable impact on its landscape and meteorology...
- Volcanism of Iceland
- Waterfalls of IcelandWaterfalls of IcelandIceland is unusually suited for waterfalls. This small island country has a north Atlantic climate that produces frequent rain or snow and a near-Arctic location that produces large glaciers, whose summer melts feed many rivers...
- Ragnar Th. SigurdssonRagnar Th. SigurdssonRagnar Th. Sigurdsson, , is a photographer specializing in landscapes portraying the natural beauty of Iceland, Greenland and the Arctic. In March 2010, he gained international recognition with his shots of the erupting volcano Eyjafjallajökull....
who photographed the 2010 eruption
External links
Photos- Satellite image of 2010 eruption by NASA
- Photos of the 2010 eruption by Fred Kamphues
- A collection of satellite images from the CIMSS Satellite Blog
- Best of Photo Collection
- More from Eyjafjallajökull – The Big Picture
- Photographs by Raw Iceland, a Reykjavik-based organization that organizes amateur and professional photography tours to the volcano
Videos and webcams
- Webcams of the eruption
- A short time-lapse from April 17, 2010. About 30 minutes played in 18 second.
- Video of the first 2010 eruption
- Video of the first 2010 eruption by Raw Iceland
- Video of the aftermath of Eyjafjallajokull eruption. Shot on July 28, 2010
- A film crew lands on Eyjafjallajokull during the 2010 eruption
Audio
Geological articles
- Univ. of Iceland: History of Eyjafjallajökull
- Geology of Katla and Eyjafjallajökull volcanoes, University of Iceland
- Magma pathways and earthquakes at Eyjafjallajökull, Icelandic Meteorological Institute (PDF)
- Institute of Earth Sciences – Eruption in Eyjafjallajökull (daily eruption status reports)
- SI / USGS Weekly Volcanic Activity Report for Eyjafjallajökull
Aviation ash forecasts
- Volcanic Ash Advisory Graphical Forecast for the North Atlantic region
- Volcanic Ash Concentration Charts for the North Atlantic region
Maps
