2010 eruptions of Eyjafjallajökull
2010 eruptions of Eyjafjallajökull | |
---|---|
Volcano | Eyjafjallajökull |
Start date | 20 March 2010[1] |
End date | 23 June 2010[1] |
Type | Strombolian and Vulcanian eruption phases |
Location | Southern Region, Iceland 63°36′N 19°36′W / 63.6°N 19.6°W |
VEI | 4[1] |
Impact | Large-scale disruption to air travel, smaller effects on farming in Iceland |
Composite map of the volcanic ash cloud spanning 14–25 April 2010 |
Between March and June 2010 a series of volcanic events at Eyjafjallajökull in Iceland caused enormous disruption to air travel across Western Europe.
The disruptions started over an initial period of six days in April 2010. Additional localised disruption continued into May 2010, and eruptive activity persisted until June 2010. The eruption was declared officially over in October 2010, after 3 months of inactivity, when snow on the glacier did not melt. From 14 to 20 April, ash from the volcanic eruption covered large areas of Northern Europe. About 20 countries closed their airspace to commercial jet traffic and it affected approximately 10 million travellers.[2]
Seismic activity started at the end of 2009 and gradually increased in intensity until on 20 March 2010, a small
Beginning on 14 April 2010, the eruption entered a second phase and created an
By the evening of 6 June 2010, a small, new crater had opened up on the west side of the main crater. Explosive activity from this new crater was observed with emission of small quantities of ash.[5] Seismic data showed that the frequency and intensity of earth tremors still exceeded the levels observed before the eruption, therefore scientists at the Icelandic Meteorological Office[6] (IMO) and the Institute of Earth Sciences, University of Iceland[7] (IES) continued to monitor the volcano.
In October 2010, Ármann Höskuldsson, a scientist at the University of Iceland Institute of Earth Sciences, stated that the eruption was officially over, although the area was still geothermally active and might erupt again.[8]
Background
Eyjafjallajökull (pronounced
The volcanic events starting in March 2010 were considered to be a single eruption divided into phases. The first eruption phase ejected olivine basaltic andesite lava[12] several hundred metres into the air in what is known as an effusive eruption. Ash ejection from this phase of the eruption was small, rising to no more than 4 km (13,000 ft) into the atmosphere.
On 14 April 2010, however, the eruption entered an
This volcanic activity was highly disruptive to air travel because of a combination of factors:[citation needed]
- The volcano is directly under the jet stream.
- The direction of the jet stream was unusually stable at the time of the eruption's second phase, continuously southeast.
- The second eruptive phase happened under 200 m (660 ft) of glacial ice. The resulting meltwater flowed back into the erupting volcano, which created two specific phenomena:
- The rapidly vaporising water significantly increased the eruption's explosive power.
- The erupting lava cooled very fast, which created a cloud of highly abrasive, glass-rich ash.
- The volcano's explosive power was enough to inject ash directly into the jet stream.
Public observations
"Volcano tourism" quickly sprang up in the wake of the eruption, with local tour companies offering day trips to see the volcano.[14] The Civil Protection Department[15] of the Icelandic Police produced regular reports about access to the area, including a map of the restricted area around Eyjafjallajokull, from which the public was forbidden. Teams from the Icelandic Association for Search and Rescue were stationed at the eruption site as part of standard safety measures and to assist in enforcing access restrictions.
Scientific observations
The London Volcanic Ash Advisory Centre (VAAC), part of the UK Met Office, was responsible for forecasting the presence of volcanic ash in the north-east Atlantic. All ash dispersion models for this geographic region were produced by the VAAC in London.
A study by the Icelandic Meteorological Office published in December 2009 indicated an increase in
The radar stations of the Meteorological Institute of Iceland did not detect any appreciable amount of volcanic ashfall during the first 24 hours of the eruption.[18] However, during the night of 22 March, they reported some volcanic ash fall reaching the Fljótshlíð area (20 to 25 km or 12 to 16 mi northwest of the eruption's location)[19] and Hvolsvöllur town (40 kilometres (25 mi) northwest of the eruption location)[19] leaving vehicles with a fine, grey layer of volcanic ash. At around 07:00 on 22 March, an explosion launched eruption columns as far as 4 km (2.5 mi) straight up into the air. This was the highest plume since the eruption started.[20] On 23 March, a small vapour explosion took place, when hot magma came into contact with nearby snowdrifts, emitting a vapour plume which reached an altitude of 7 km (23,000 ft), and was detected on radar from the Meteorological Institute of Iceland. After that, many further vapour explosions occurred.[21]
By 26 March 2010, the
This unusual seismic activity, along with the rapid movement of the Earth's crust in the area, gave
The grounding of European flights avoided about 3.44×108 kg of CO2 emissions per day, while the volcano emitted about 1.5×108 kg of CO2 per day.[25]
Phase 1: Effusive eruption
The first phase of the eruption lasted from 20 March to 12 April 2010 and was characterised by olivine basaltic andesite lava flowing from various eruptive vents on the flanks of the mountain.
Evacuations
About 500 farmers and their families had to escape from the areas of
Effects on the river
On 22 March, a
Fissure
The first phase of the 2010 eruption began late on the evening of 20 March at the Eyjafjallajökull.
The initial visual report of the eruption was at 23:52 GMT, when a red cloud was seen at the north slopes of
A
On 25 March 2010, while studying the eruption,
A new fissure opened on 31 March, around 200 m (700 ft) northwest of the original fissure.[44] Many witnesses were present while the new fissure opened. It was a bit smaller, around 300 m (1,000 ft) long according to witnesses, and lava coming from it started to flow into Hvannárgil canyon. These two erupting fissures shared the same magma chamber, according to geophysicists. No unusual seismic activity was detected at the time the new fissure appeared, nor any crustal expansion according to many seismometers and GPS recorders situated in nearby areas.[45][46]
Geophysicist Magnús Tumi Einarsson said (at a press meeting in Hvolsvöllur on 21 March) that this eruption was small compared to, for example, the eruption of Hekla in 2000. The eruption, rather than taking place under the ice cap of the glacier, occurred in the mountain pass between the Eyjafjallajökull and Mýrdalsjökull glaciers. As long as the fissure was not near the glacier, the risk of flooding was minimal; however, the fissure could extend into the ice cap, thereby greatly increasing the risk of flooding.[47]
Phase 2: Explosive eruption
After a short hiatus in eruptive activity, and a large increase in seismic activity 23:00 on 13 April and 1:00 on 14 April, a new set of craters opened early in the morning of 14 April 2010 under the volcano's ice-covered central summit caldera. The earthquake swarm was followed by the onset of a seismic eruption tremor. Meltwater started to emanate from the ice cap around 07:00 on 14 April and an eruption plume was observed in the early morning. Visual observations were greatly restricted due to cloud cover over the volcano, but an aeroplane of the Icelandic Coast Guard imaged eruptive craters with radar instruments. A series of vents along a two-kilometre-long north–south-oriented fissure was active, with meltwater flowing mostly down the northern slopes of the volcano, but also to the south. An ash-loaded eruption plume rose to more than 8 km (26,000 ft), deflected to the east by westerly winds.[citation needed]
Ash analysis
Samples of volcanic ash collected near the eruption showed a silica concentration of 58%—much higher than in the lava flows.
Impact on farming
The Icelandic Food and Veterinary Authority released an announcement on 18 April 2010, asking that all horse owners who keep their herds outside be on the alert for ash fall. Where ash fall was significant, all horses had to be sheltered indoors.
Timeline of the second eruption phase
Unlike the earlier eruption phase, the second phase occurred beneath glacial ice. Cold water from melted ice quickly chilled the lava, causing it to fragment into highly abrasive glass particles that were then carried into the eruption plume. This, together with the magnitude of the eruption (estimated to be
In addition to volcanic ash being very hazardous to aircraft,[53] the location of this eruption directly under the jet stream ensured that the ash was carried into the heavily used airspace over northern and central Europe.
Phase 3: Return to dormancy
By the morning of 24 May 2010, the view from the web camera installed on Þórólfsfell[54] showed only a plume of water vapour surrounded by a bluish haze caused by emission of sulphurous gases. Due to the large quantities of dry volcanic ash lying on the ground, surface winds frequently lifted up an "ash mist" that significantly reduced visibility and made web camera observation of the volcano impossible.[55]
On 21 June 2010, data from seismic recorders in the area indicated that the frequency and strength of earth tremors had diminished, but were continuing.[56]
In October 2010, Ármann Höskuldsson, a scientist at the University of Iceland Institute of Earth Sciences, stated that the eruption was officially over, although the area was still geothermally active and might erupt again.[8]
During the eruption, the
Volume of erupted material and magma discharge
The Institute of Earth Sciences[57] made a preliminary estimate of erupted material in the first three days of the eruption on 14 April 2010 at Eyjafjallajökull. The erupted products were fragmented material, the majority fine-grained airborne tephra. Eruptive products can be split into three categories along with preliminary estimated erupted volumes:
- Material (tephra) in the ice cauldrons around the volcanic vents: 30 million cubic metres (39,000,000 cu yd)
- Tephra filling the glacial lagoon of Gígjökulslón, carried by floods down the outlet glacier Gígjökull: 10 million cubic metres (13,000,000 cu yd)
- Airborne tephra that was carried to the east and south of the volcano, uncompacted tephra fallout from eruption plume: 100 million cubic metres (130,000,000 cu yd)
Total: 140 million cubic metres (180,000,000 cu yd) which corresponds to some 70–80 million cubic metres (92,000,000–105,000,000 cu yd) of magma. The magma discharge rate was about 300 cubic metres per second (11,000 cu ft/s) or 750 t/s. This was 10–20 times the average discharge rate in the preceding flank eruption at Fimmvörðuháls. (First eruption on 20 March 2010).[58]
The IES updated the eruption flow rate on 21 April 2010 to an estimation less than 30 cubic metres per second (1,100 cu ft/s) of magma, or 75 t/s, with a large uncertainty. IES also noted that the eruption continue with less explosive activity.[59]
Health effects
No human fatalities were reported from the 2010 eruption of Eyjafjallajökull. Those who lived near the volcano had high levels of irritation symptoms, though their lung function was not lower than expected.[60] Six months later, the population living in the area had more respiratory symptoms than a control group from North Iceland, with no ashfall.[61] In Scotland, the number of phone calls to health services for respiratory and eye irritation did not rise significantly.[62]
Effects of the ash plume on air travel
Volcanic ash is a major hazard to aircraft.
Short- and long-term weather and environmental effects
At the mouth of the crater, the gases, ejecta, and volcanic plume created a rare
High-fluoride
As of 15 April, the eruption was not large enough to have an effect on global temperatures like that of Mount Pinatubo and other major past volcanic eruptions.[71][72] One previous related sequence of eruptions of this volcano, beginning in 1821 is recorded as having lasted for over two years, but no single set of major eruptions is known to have lasted more than 'several days'.
Comparison to past eruptions
The eruptions of Eyjafjallajökull and the largest ash plume associated with the second eruption phase were not unparalleled in either volume or abundance; however, the location was the critical factor because it affected air travel across Europe. Neither phase of the eruption was unusually powerful.[73][74] Other notable volcanic eruptions include the eruption of Mount Pinatubo of 1991 of VEI 6.[4] This eruption lasted eight days, from 7 – 15 June of that year, with an ash cloud that would have required additional days to dissipate,[75] and resulted in worldwide abnormal weather and decrease in global temperature over the next few years. However, the second phase of Eyjafjallajökull's eruption lasted longer than that of Mount Pinatubo.
In popular culture
- The eruptions were a key plot point of the 2013 French comedy Eyjafjallajökull.[76]
- British-American rapper MF Doom references the eruptions in the opening lines of his song "Guv'nor", on his 2012 album Key to the Kuffs, with the line "Catch a throatful from the fire vocal, with ash and molten glass like Eyjafjallajökull".[77]
- Writing for Time, Serbian performance artist Marina Abramović used Icelandic musician Björk's reverential reaction to the eruptions to praise her uniqueness as an artist.[78]
See also
- 2010 eruptions of Mount Merapi
- 2014–2015 eruption of Bárðarbunga
- Air travel disruption after the 2010 Eyjafjallajökull eruption
- British Airways Flight 9
- Effects of the April 2010 Eyjafjallajökull eruption
- KLM Flight 867
- Laki
- List of volcanoes in Iceland
- North Atlantic oscillation
- Timeline of volcanism on Earth
- Tuya
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External links
- Frequently Asked Questions on the Eruption in Iceland – from the Icelandic Met Office
- BBC webpage with film of the volcano, taken from 500m from the crater's edge, by Chris Weber on 13 May 2010
- Volcanic Ash and Aviation Safety – SKYbrary guidance to pilots and controllers concerning the effects of volcanic ash.
- Collection of Scientific Earth Observations and Models
- NASA Observes the Icelandic Volcano
- NASA Earth Observatory satellite imagery
- Satellite evidence of hot lava flows from an Icelandic volcano (CIMSS Satellite Blog) (March 2010)
- Description of beginning of current eruption, (March 2010), Icelandic Met Office
- Volcanoes in European history – Podcast placing the Eyjafjallajökull eruption in a historical perspective.
- Webpages and -links related to 2010 Eyjafjallajökull eruptions, Icelandic Met Office
Photography
- Photos from Icelanders and by visitors (Flickr Group)
- A short time-lapse from 17 April 2010. About 30 minutes played in 18 seconds.
- Photos of the 2010 eruptions by Fred Kamphues
- Icelandic Coast Guard, radar images of the volcano