Grímsvötn
Encyclopedia
The Grímsvötn sub-glacial lakes ('krimsvœʰtn̥; vötn = "waters", singular: ) and the volcano of the same name are in South-East Iceland
. They are in the highlands of Iceland
at the northwestern side of the Vatnajökull
ice-cap. The lakes are at 64°25′N 17°20′W, at an elevation of 1725 m (5,659.4 ft). Beneath the lakes is the magma chamber
of the Grímsvötn volcano.
Grímsvötn is a basaltic volcano which has the highest eruption frequency of all the volcanoes in Iceland and has a southwest-northeast-trending fissure system. The massive climate-impacting Laki
fissure eruption of 1783–1784 was a part of the same fissure system. Grímsvötn was erupting at the same time as Laki during 1783, but continued to erupt until 1785. Because most of the volcano lies underneath Vatnajökull, most of its eruptions have been subglacial
and the interaction of magma and meltwater from the ice causes phreatomagmatic
explosive activity.
On 21 May 2011 at 19:25 UTC, an eruption
began, with 12 km (7 mi) high plumes
accompanied by multiple earthquake
s, resulting in cancellation of 900 flights in Iceland, and in the United Kingdom
, Greenland
, Germany
, Ireland
, Norway
and Scotland
on 22–25 May. Until 25 May the eruption scale had been larger than that of the 2010 eruption
of Eyjafjallajökull
. The eruption paused at 02:40 UTC on 25 May 2011, although there was some explosive activity from the tephra vents affecting only the area around the crater.
. Eruptions melt enough ice to fill the Grímsvötn caldera with water, and the pressure may be enough to suddenly lift the icecap, allowing huge quantities of water to escape rapidly. Consequently, the Grímsvötn caldera is monitored very carefully.
When a large eruption occurred in 1996, geologist
s knew well in advance that a glacial burst was imminent. It did not occur until several weeks after the eruption finished, but monitoring ensured that the Icelandic ring road (Hringvegur) was closed when the burst occurred. A section of road across the Skeiðará
sandur
was washed away in the ensuing flood, but no one was hurt.
from the eruption fell as far away as mainland Europe
and caused short-term disruption of airline traffic into Iceland, but again no glacial burst followed the eruption.
s were recorded twice around Grímsvötn on 2 and 3 October 2010, possibly indicating an impending eruption. At the same time, sudden inflation was measured by GPS in the volcano, indicating magma movement under the mountain. On 1 November 2010 meltwater from the Vatnajökull glacier was flowing into the lake, suggesting that an eruption of the underlying volcano might be imminent.
accompanied by multiple earthquake
s.
The ash cloud from the eruption rose to 20 km (12.4 mi), and is so far 10 times larger than the 2004 eruption, and the strongest in Grímsvötn in the last 100 years.
During 22 May the ash plume fell to around 10 km altitude, rising occasionally to 15 km. On 23 May, the eruption was releasing about 2000 tons of ash per second, totalling 120 million tons in the first 48 hours. The 2011 eruption of Grímsvötn thus qualified as at least 4 (VEI4) on the Volcanic Explosivity Index
(VEI), releasing more ash in the first 24 hours than Eyjafjallajökull released during its entire 2010 eruption. On 24 May poor weather prevented visual observation of the eruption plume, but it had an estimated height of below 5 km, implying that the eruption is significantly weaker than on previous days. A IMO scientific flight over the eruption on the evening of 24 May site showed there was explosive activity from two vents which are surrounded by tephra debris, with the eruption plume reaching between 3 and 7.5 km in height.
On 25 May Iceland Met Office has confirmed that the eruption has paused at 02.40 local time on 25th. However there are still pulsating explosions producing ash and steam clouds, some reaching a few kilometres in height, rising up from the vents. There is still widespread ash in cloud layers up to 5 km from the eruption site.
On 26 May the Icelandic Meteorological Office and the University of Iceland
reported that ashfall is only occurring adjacent to the eruption site. Visual observations indicate that little ice meltwater was produced during the eruption, so that an outburst flood (jökulhlaup) is not expected. Joint status reports will no longer be issued, unless something notable is observed.
and a small part of Denmark on subsequent days. On 24 May the disruption spread to Northern Ireland and to airports in northern England. On 25 May the disruption spread to Northern Germany - airports at Hamburg
and Bremen
were closed for a few hours. On 27 May Greenlandic airspace was closed due to a concentration of ash over Greenland and the North Atlantic.
The cancellation of 900 out of 90 000 European flights in the period 23-25 May was much less widespread than the 2010 disruption
after the Eyjafjallajökull
eruption.
was detected in water of the Grímsvötn lake under the glacier, the first time that bacteria have been found in a subglacial lake. The lakes never freeze because of the volcanic heat. The bacteria can also survive at low concentrations of oxygen
. The site is a possible analogue for life on the planet
Mars
, because there are also traces of volcanism and glaciers on Mars and thus the findings could help identify how to look for life on Mars.
is known to be associated with increased activity in Grímsvötn. Seismic activity has been increasing in the area in recent years, indicating the entry of magma.
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...
. They are in the highlands of Iceland
Highlands of Iceland
The Highlands of Iceland cover most of the interior of Iceland. They are situated above 400–500 metres and are mostly an uninhabitable volcanic desert, because the water precipitating as rain or snow infiltrates so quickly into the ground that it is unavailable for plant growth, which results...
at the northwestern side of the Vatnajökull
Vatnajökull
Vatnajökull is the largest glacier in Iceland. It is located in the south-east of the island, covering more than 8% of the country.-Size:With an area of 8,100 km², Vatnajökull is the largest ice cap in Europe by volume and the second largest in area Vatnajökull is the largest glacier in...
ice-cap. The lakes are at 64°25′N 17°20′W, at an elevation of 1725 m (5,659.4 ft). Beneath the lakes is 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 Grímsvötn volcano.
Grímsvötn is a basaltic volcano which has the highest eruption frequency of all the volcanoes in Iceland and has a southwest-northeast-trending fissure system. The massive climate-impacting Laki
Laki
Łąki may refer to the following places in Poland:*Łąki, Lower Silesian Voivodeship *Łąki, West Pomeranian Voivodeship *Łąki, Lublin Voivodeship...
fissure eruption of 1783–1784 was a part of the same fissure system. Grímsvötn was erupting at the same time as Laki during 1783, but continued to erupt until 1785. Because most of the volcano lies underneath Vatnajökull, most of its eruptions have been subglacial
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...
and the interaction of magma and meltwater from the ice causes phreatomagmatic
Phreatomagmatic eruption
Phreatomagmatic eruptions are defined as juvenile forming eruptions as a result of interaction between water and magma. They are different from magmatic and phreatic eruptions. The products of phreatomagmatic eruptions contain juvenile clasts, unlike phreatic eruptions, and are the result of...
explosive activity.
On 21 May 2011 at 19:25 UTC, an eruption
2011 eruption of Grímsvötn
The 2011 eruption of Grímsvötn is an eruption in Grímsvötn, Iceland's most active volcano, which caused disruption to air travel in North-Western Europe from 22–25 May 2011. The last eruption of Grímsvötn was in 2004, with the previous most powerful eruptions in 1783, 1873 and 1902...
began, with 12 km (7 mi) high plumes
Eruption column
An eruption column consists of hot volcanic ash emitted during an explosive volcanic eruption. The ash forms a column rising many kilometres into the air above the peak of the volcano. In the most explosive eruptions, the eruption column may rise over 40 km, penetrating the stratosphere...
accompanied by multiple earthquake
Earthquake
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, resulting in cancellation of 900 flights in Iceland, and in the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
, Greenland
Greenland
Greenland is an autonomous country within the Kingdom of Denmark, located between the Arctic and Atlantic Oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe for...
, Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
, Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...
, Norway
Norway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...
and Scotland
Scotland
Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...
on 22–25 May. Until 25 May the eruption scale had been larger than that of the 2010 eruption
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...
of Eyjafjallajökull
Eyjafjallajökull
Eyjafjallajökull is one of the smaller ice caps 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 . The volcano has erupted relatively frequently since the last glacial period, most recently in...
. The eruption paused at 02:40 UTC on 25 May 2011, although there was some explosive activity from the tephra vents affecting only the area around the crater.
Jökulhlaup
Eruptions in the caldera regularly cause glacial outbursts known as jökulhlaupJökulhlaup
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...
. Eruptions melt enough ice to fill the Grímsvötn caldera with water, and the pressure may be enough to suddenly lift the icecap, allowing huge quantities of water to escape rapidly. Consequently, the Grímsvötn caldera is monitored very carefully.
When a large eruption occurred in 1996, geologist
Geologist
A geologist is a scientist who studies the solid and liquid matter that constitutes the Earth as well as the processes and history that has shaped it. Geologists usually engage in studying geology. Geologists, studying more of an applied science than a theoretical one, must approach Geology using...
s knew well in advance that a glacial burst was imminent. It did not occur until several weeks after the eruption finished, but monitoring ensured that the Icelandic ring road (Hringvegur) was closed when the burst occurred. A section of road across the Skeiðará
Skeiðará
The river Skeiðará is a relatively short glacier river . It has its source on the glacier Skeiðarárjökull, one of the southern arms of the Vatnajökull in the south of Iceland....
sandur
Sandur
A sandur is a glacial outwash plain formed of sediments deposited by meltwater at the terminus of a glacier.- Formation :Sandar are found in glaciated areas, such as Svalbard, Kerguelen Islands, and Iceland...
was washed away in the ensuing flood, but no one was hurt.
1998 and 2004 eruptions
A week-long eruption occurred at Grímsvötn starting on 28 December 1998, but no glacial burst occurred. In November 2004, a week-long eruption occurred. Volcanic ashVolcanic ash
Volcanic ash consists of small tephra, which are bits of pulverized rock and glass created by volcanic eruptions, less than in diameter. There are three mechanisms of volcanic ash formation: gas release under decompression causing magmatic eruptions; thermal contraction from chilling on contact...
from the eruption fell as far away as mainland 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...
and caused short-term disruption of airline traffic into Iceland, but again no glacial burst followed the eruption.
2010 pre-eruption glacial flood
Harmonic tremorHarmonic tremor
Harmonic tremor describes a long-duration release of seismic energy, with distinct spectral lines, that often precedes or accompanies a volcanic eruption...
s were recorded twice around Grímsvötn on 2 and 3 October 2010, possibly indicating an impending eruption. At the same time, sudden inflation was measured by GPS in the volcano, indicating magma movement under the mountain. On 1 November 2010 meltwater from the Vatnajökull glacier was flowing into the lake, suggesting that an eruption of the underlying volcano might be imminent.
Eruption
On 21 May 2011 at 19:25 UTC, an eruption began, with 12 km (7 mi) high plumesEruption column
An eruption column consists of hot volcanic ash emitted during an explosive volcanic eruption. The ash forms a column rising many kilometres into the air above the peak of the volcano. In the most explosive eruptions, the eruption column may rise over 40 km, penetrating the stratosphere...
accompanied by multiple earthquake
Earthquake
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.
The ash cloud from the eruption rose to 20 km (12.4 mi), and is so far 10 times larger than the 2004 eruption, and the strongest in Grímsvötn in the last 100 years.
During 22 May the ash plume fell to around 10 km altitude, rising occasionally to 15 km. On 23 May, the eruption was releasing about 2000 tons of ash per second, totalling 120 million tons in the first 48 hours. The 2011 eruption of Grímsvötn thus qualified as at least 4 (VEI4) on the Volcanic Explosivity Index
Volcanic Explosivity Index
The Volcanic Explosivity Index was devised by Chris Newhall of the U.S. Geological Survey and Stephen Self at the University of Hawaii in 1982 to provide a relative measure of the explosiveness of volcanic eruptions....
(VEI), releasing more ash in the first 24 hours than Eyjafjallajökull released during its entire 2010 eruption. On 24 May poor weather prevented visual observation of the eruption plume, but it had an estimated height of below 5 km, implying that the eruption is significantly weaker than on previous days. A IMO scientific flight over the eruption on the evening of 24 May site showed there was explosive activity from two vents which are surrounded by tephra debris, with the eruption plume reaching between 3 and 7.5 km in height.
On 25 May Iceland Met Office has confirmed that the eruption has paused at 02.40 local time on 25th. However there are still pulsating explosions producing ash and steam clouds, some reaching a few kilometres in height, rising up from the vents. There is still widespread ash in cloud layers up to 5 km from the eruption site.
On 26 May the Icelandic Meteorological Office and the University of Iceland
University of Iceland
The University of Iceland is a public research university in Reykjavík, Iceland, and the country's oldest and largest institution of higher education. Founded in 1911, it has grown steadily from a small civil servants' school to a modern comprehensive university, providing instruction for about...
reported that ashfall is only occurring adjacent to the eruption site. Visual observations indicate that little ice meltwater was produced during the eruption, so that an outburst flood (jökulhlaup) is not expected. Joint status reports will no longer be issued, unless something notable is observed.
Disruption to air travel
Disruption to air travel in Iceland commenced on 22 May, followed by Greenland, Scotland, Norway, SvalbardSvalbard
Svalbard is an archipelago in the Arctic, constituting the northernmost part of Norway. It is located north of mainland Europe, midway between mainland Norway and the North Pole. The group of islands range from 74° to 81° north latitude , and from 10° to 35° east longitude. Spitsbergen is the...
and a small part of Denmark on subsequent days. On 24 May the disruption spread to Northern Ireland and to airports in northern England. On 25 May the disruption spread to Northern Germany - airports at Hamburg
Hamburg
-History:The first historic name for the city was, according to Claudius Ptolemy's reports, Treva.But the city takes its modern name, Hamburg, from the first permanent building on the site, a castle whose construction was ordered by the Emperor Charlemagne in AD 808...
and Bremen
Bremen
The City Municipality of Bremen is a Hanseatic city in northwestern Germany. A commercial and industrial city with a major port on the river Weser, Bremen is part of the Bremen-Oldenburg metropolitan area . Bremen is the second most populous city in North Germany and tenth in Germany.Bremen is...
were closed for a few hours. On 27 May Greenlandic airspace was closed due to a concentration of ash over Greenland and the North Atlantic.
The cancellation of 900 out of 90 000 European flights in the period 23-25 May was much less widespread than the 2010 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...
after the Eyjafjallajökull
Eyjafjallajökull
Eyjafjallajökull is one of the smaller ice caps 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 . The volcano has erupted relatively frequently since the last glacial period, most recently in...
eruption.
Bacteria in the subglacial lakes
In summer 2004, a community of bacteriaBacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
was detected in water of the Grímsvötn lake under the glacier, the first time that bacteria have been found in a subglacial lake. The lakes never freeze because of the volcanic heat. The bacteria can also survive at low concentrations of oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
. The site is a possible analogue for life on the planet
Planet
A planet is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.The term planet is ancient, with ties to history, science,...
Mars
Mars
Mars is the fourth planet from the Sun in the Solar System. The planet is named after the Roman god of war, Mars. It is often described as the "Red Planet", as the iron oxide prevalent on its surface gives it a reddish appearance...
, because there are also traces of volcanism and glaciers on Mars and thus the findings could help identify how to look for life on Mars.
Future trends
Studies indicate that volcanic activity in Iceland rises and falls so that e.g. the frequency and size of eruptions in and around the Vatnajökull ice cap varies with time. It is believed that four eruptions, that have taken place in the last fifteen years, are the beginning of an active period, during which an eruption in Grímsvötn in Vatnajökull may be expected every 2–7 years. Parallel volcanic activity in nearby BárðarbungaBárðarbunga
Bárðarbunga is an Icelandic stratovolcano located under the ice cap of Vatnajökull glacier, rising to 2,009 m above sea level, making it the second highest mountain in Iceland, just about 101 m lower than Hvannadalshnjúkur....
is known to be associated with increased activity in Grímsvötn. Seismic activity has been increasing in the area in recent years, indicating the entry of magma.
See also
- Volcanism in Iceland
- List of volcanoes in Iceland
- Geography of IcelandGeography of IcelandIceland is a medium-sized island in the North Atlantic ocean. The island is located east of Greenland and immediately south of the Arctic Circle, atop the divergent boundary of the Mid-Atlantic Ridge in the North Atlantic Ocean. It lies about from New York City and from Scotland...
- 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...
- Glacial lake outburst floodGlacial lake outburst floodA 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...
- Iceland plumeIceland plumeThe Iceland Plume is a postulated upwelling of anomalously hot rock in the Earth's mantle beneath Iceland. Its origin is thought to lie deep in the mantle, perhaps at the boundary between the core and the mantle at ca. 2880 km depth. Opinions differ as to whether seismic studies have imaged...
- Iceland hotspotIceland hotspotThe Iceland hotspot is a hotspot which is partly responsible for the high volcanic activity which has formed the island of Iceland.-Description:...
- Lakes of Iceland
- List of islands of Iceland
- Timetable of major worldwide volcanic eruptionsTimetable of major worldwide volcanic eruptionsThis article is a list of volcanic eruptions of approximately at least magnitude 6 on the Volcanic Explosivity Index or equivalent sulfur dioxide emission around the Quaternary period. Some cooled the global climate; the extent of this effect depends on the amount of sulfur dioxide emitted...
- Plate tectonicsPlate tectonicsPlate tectonics is a scientific theory that describes the large scale motions of Earth's lithosphere...
External links
- Update on Grímsvötn Activity – from the Icelandic Met Office and University of Iceland (updated at least daily)
- Current seismology around Grímsvötn – Earthquakes in last 48 hours
- Webcam by Míla, Iceland (exact location unknown)
- Webcam at Jökulsárlón, south of the volcano, by Míla, Iceland
- Grímsvötn volcanic ash advisory from regional Volcanic Ash Advisory Centre, London (updated every 6 hours)
- Grímsvötn updates from NATS – UK air traffic control plus the Eastern part of the North Atlantic
- BBC news report of the 23 May 2011 eruption
- Report on the start of the Grímsvötn eruption from the Icelandic Met Office
- Photo report of the November 2004 eruption
- Independent news report of the 2004 eruption