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| Aug. 19, 2014: A warning sign blocks the road to Bardarbunga volcano, some 12.5 miles away, in the north-west region of the Vatnajokull glacier.REUTERS |
Mikahel Love, IIO
A subglacial eruption is underway at the Bardarbunga volcano in Iceland. Seismic data indicates that lava from the volcano is melting ice beneath the Vatnajokull glacier. An eruption that could cause "significant emission of ash into the atmosphere."
Iceland volcano raises aviation alert, may disrupt flights
No-fly zone around Iceland volcano
Iceland evacuates an area north of the country's Bardarbunga volcano, as the country's civil protection agency says it cannot rule out an eruption.
REYKJAVIK, Iceland – Iceland raised its aviation alert to red Saturday as a subglacial eruption began at the restless Bardarbunga volcano, which has been rattled by thousands of earthquakes in the past week, the country's Meteorological Office said.
Iceland's Meteorological Office is reporting a surge in seismic activity at the restless Bardarbunga volcano, but sees no evidence yet of any eruptions. Seismic data indicated that lava from the volcano was melting ice beneath the Vatnajokull glacier, Iceland's largest, Met Office vulcanologist Melissa Pfeffer said.
She said it was not clear when, or if, the eruption would melt through the ice -- which is between 100 to 400 meters (330 to 1,300 feet) thick -- and send steam and ash into the air.
The eruption led Iceland to raise its aviation alert level to red, indicating an eruption that could cause "significant emission of ash into the atmosphere." Red is the highest alert warning on a five-point scale.
Aviation authorities declared a no-fly zone around the volcano but did not shut Icelandic airspace.
Pfeffer said scientists were flying over the glacier Saturday to look for changes on its surface. Scientists were also monitoring a hydrological station downstream from the volcano for flooding -- a common result of volcanic eruptions in Iceland.
Authorities evacuated several hundred people earlier this week from the highlands north of the Vatnajokull glacier as a precaution. The remote area, 200 miles (320 kilometers) east of Reykjavik, is uninhabited but popular with hikers.
Iceland sits on a volcanic hot spot in the Atlantic's mid-oceanic ridge and eruptions occur frequently, triggered when the Earth's plates move and when magma from deep underground pushes its way to the surface.
A 2010 eruption of Iceland's Eyjafjallajokul volcano produced an ash cloud that caused a week of international aviation chaos, with more than 100,000 flights cancelled. Aviation regulators since have reformed policies about flying through ash, so a new eruption would be unlikely to cause that much disruption. ( video and pics of the 2010 even at the end of this report )
Pfeffer said the amount of ash produced would depend on the thickness of the ice.
"The thicker the ice, the more water there is, the more explosive it will be and the more ash-rich the eruption will be," she said.
How to track the eruption
The Icelandic Met Office has been offering daily — and sometimes more than daily — updates on the volcano. There are also frequent English-language updates from the Icelandic newspaper Morgunblaðið.
Volcano obsessives can find all the different livestreams here.
On top of that, there are plenty of volcano experts on Twitter who are watching the eruption closely — including Dave McGarvie, Gisli Olafsson, and Erik Klemetti. Journalist Alexandra Witze has been tracking Icelandic volcanoes for a long time and is definitely worth following. And John Stevenson has done a lot of excellent work on the impacts of volcanic eruptions on aviation.
Via
Reykjavik, Iceland — Iceland's Meteorological Office says a subglacial eruption is underway at the Bardarbunga volcano, which has been rattled by thousands of earthquakes over the past week.
The office reports that a 4.5 magnitude earthquake occurred Saturday afternoon local time. On Friday, the Met Office reported:
One earthquake of magnitude 4.7 was measured in the Bárðarbunga caldera at 4 km depth yesterday evening at 23:50. This large event was at similar location as earthquakes of magnitude larger than three that were seen yesterday. Large events in Bárðarbunga are interpreted as adjustments of the caldera rim related to decompression in the caldera since the beginning of the unrest. The activity continues and an eruption can therefore not be ruled out.Vulcanologist Melissa Pfeffer said seismic data indicates that lava from the volcano is melting ice beneath the Vatnajokull glacier. She said it was not clear when, or if, the eruption would melt the ice and send steam and ash into the air.
Minutes earlier, Iceland raised its aviation alert for the volcano to the highest level of red on Saturday, indicating an eruption that could cause "significant emission of ash into the atmosphere." Red is the highest alert warning on a five-point scale.
Scientists had planned to fly over the glacier later Saturday to look for changes on the surface but it was not clear if that would still take place.
Authorities had evacuated several hundred people earlier this week from the highlands north of the Vatnajokull glacier as a precaution. The area is uninhabited but popular with hikers.
Iceland sits on a volcanic hot spot in the Atlantic's mid-oceanic ridge and eruptions have occurred frequently, triggered when the Earth's plates move and when magma from deep underground pushes its way to the surface.
A 2010 eruption of the Eyjafjallajokul volcano produced an ash cloud that caused a week of international aviation chaos, with more than 100,000 flights cancelled. Aviation regulators since have reformed policies about flying through ash, so a new eruption would be unlikely to cause that much disruption.
Pfeffer said the amount of ash produced would depend on the thickness of the ice.
"The thicker the ice, the more water there is, the more explosive it will be and the more ash-rich the eruption will be," she said.
Earlier this week, scientists said there are two likely scenarios:
One is an explosion outside the Vatnajokull glacier, leading to minor ash emissions and troubles locally. The second possibility is an eruption occurring inside the glacier. Seismologist Martin Hensch says the latter could lead to ash being sent high into the atmosphere.
Met Office seismologist Martin Hensch said the risk of any disruptive ash cloud similar to the one in 2010 would depend on how high any ash would be thrown, how much there would be and how fine-grained it would be.
Bardarbunga is Iceland's largest volcanic system, located under the ice cap of the Vatnajokull glacier in the southwest of Iceland. It is in a different range to Eyjafjallajokull.
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Video of a volcano in 25 March 2010 at Eyjafjallajoekull in southern Iceland continues to erupt under an ice sheet
RELATED: 2010 Pics of the region
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| Eyjafjallajökull's eruption in 2010 caused mayhem with travel plans around the world. Photograph: Arctic-Images/Getty Images |
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| Smoke and steam hang over the volcano under the Eyjafjalla glacier in Iceland, early Thursday April 15, 2010. (AP Photo/Brynjar Gaudi) |
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| Tourists gather to watch lava spurt out of the site of a volcanic eruption at the Eyjafjallajökull volcano on March 27, 2010. Up to 800 people were evacuated in Iceland early on April 14, 2010 due to a volcano eruption under the Eyjafjallajokull glacier in the south of the island, police and geophysicists said. (HALLDOR KOLBEINS/AFP/Getty Images) |
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| North view of the Eyjafjallajökull on 4 April 2010 from an altitude of 10.000 meters. This picture was taken minutes after taking off, heading east towards Copenhagen. (Photo credit: Wikipedia) |
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| Plane flies near to assess activity |
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| Ash darkens sky |
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