Iceland raises volcano aviation alert briefly

[Buster's Uncle]

Iceland raises volcano aviation alert briefly
Associated Press
By JENNA GOTTLIEB  17 minutes ago



This is a Aug. 19, 2014 file image taken from video of a sign is posted on the road next to Bardarbunga, a subglacial stratovolcano located under Iceland's largest glacier. Earthquakes are rocking Iceland's Bardarbunga volcano, adding to concerns that magma movements may trigger an eruption that could hinder air traffic. Iceland's Met Office says two earthquakes measuring over magnitude 5 shook the volcano under the vast Vatnajokull glacier on Wednesday Aug. 27 2014. Some 500 quakes have hit the area since midnight. (AP Photo/Courtesy Channel 2 Iceland, File)



REYKJAVIK, Iceland (AP) — Icelandic authorities briefly raised the aviation warning code to red Friday after a small fissure eruption near Bardarbunga volcano, but no volcanic ash was detected by the radar system.

The eruption took place the Holuhraun lava field, five kilometers (three miles) north of Dyngjujoekull glacier, Iceland's Meteorological Office said. The event was described as being not highly explosive — and thus not producing much of the fine ash that can affect aircraft engines.

The eruption began just after midnight local time (0000 GMT Friday; 2000 EDT Thursday) and ended at 0400 GMT Friday (midnight EDT Thursday).

The airspace was closed three nautical miles around the eruption area up to 5,000 feet (1,524 meters) — meaning it did not affect commercial flights flying over Iceland. The aviation code for Bardarbunga was originally raised to red — meaning that an eruption was underway — but was lowered to the lesser orange level as there was no significant ash production, the Civil Protection Department said.

The so-called fissure eruption was a crack that opened up above a magma intrusion. It didn't produce any significant ash.

The eruption raised concerns because of one in 2010, when Iceland's Eyjafjallajoekull volcano erupted and sparked a week of international aviation chaos. Thousands of flights were canceled when aviation officials closed Europe's air space for five days, fearing that volcanic ash could harm jet engines.


http://news.yahoo.com/icelandic-officials-eruption-near-bardarbunga-083416388.html

[Buster's Uncle]

Iceland declares volcano eruption area safe for aircraft
AFP
By Haukur Holm  6 hours ago



Icelandic officials have raised the alert to the highest level.



Reykjavik (AFP) - Iceland on Friday temporarily banned air traffic near its largest volcano after a lava field erupted overnight, threatening a repeat of the global travel chaos four years ago when another peak blew.

The aviation "red alert" for Bardarbunga volcano was lifted in the late morning when it became clear that the eruption was minor and did not release large quantities of ash.

During the alert, Iceland's airports remained opened with no disruption to flights, according to the national airport operator Isavia.

In 2010, another Icelandic volcanic eruption caused the biggest closure of European airspace in peacetime, halting 100,000 flights and stranding eight million passengers.

While Bardarbunga -- located under Europe's largest glacier -- had not yet started spewing ash as of Friday afternoon, the release of a massive cloud remained a possible scenario with potentially dire consequences for aviation.

"An eruption began... just after midnight (0000 GMT)," said the civil protection office in a statement, adding that it took place in a lava field three miles (five kilometres) north of the volcano, creating a volcanic fissure a half a mile (900 metres) long.



Scientists fix seismometer and communication equipment over Bardarbunga volcano, Iceland (AFP Photo/Arni Saeberg)


"No volcanic ash has been detected by the radar system at the moment. The earthquake caused by the eruption is small, indicating an... eruption without significant explosive activity," it said.


-Little 'explosive activity'-

The authority described the event as an "effusive eruption without significant explosive activity" -- meaning the lava flow was mostly on the surface of the volcano with little "airborne ash material".

Tumi Gudmundsson, a geophysicist at the University of Iceland told public broadcaster RUV that the eruption was an "accidental" knock-on effect of seismic activity inside the volcano but that an explosive eruption of volcano itself could still occur and was impossible to predict.

When the red alert was first issued in the early hours of Friday morning a vast area of Icelandic airspace was closed off -- including the northern airport of Akureyri which has regular internal flights and connections to Greenland and several European cities.



Computer screens show seismic activity from the Bardarbunga volcanic eruption, at Iceland's Meteorological Institute in Reykjavik, on August 23, 2014 (AFP Photo/Halldor Kolbeins)


Later the restricted area was reduced to 10 nautical miles (18.5 kilometres) around the site of the eruption at altitudes below 5,000 feet (about 1,500 metres).

The Bardarbunga volcano system became active on August 16, producing hundreds of tremors daily.

Four days later hundreds of people were evacuated from the area north of the Vatnajoekull glacier which covers the volcano and is largely uninhabited, with only trekking cabins and campsites used by tourists and hunters in the summer months.

Friday was the second time in less than a week that Icelandic authorities issued a red alert to aviation but then lowered the level to orange -- meaning that eruption is possible but not imminent -- soon after.

The alert around Bardarbunga was first raised to red from orange on August 23, with earthquakes shaking the volcanic system more than 20 times an hour on Tuesday alone.



An aerial picture taken on August 23, 2014 shows the glacier near the Bardarbunga volcano, Iceland (AFP Photo/Arni Saeberg)


One of the quakes measured 5.7, the most powerful in the area since 1996.

Bardarbunga, in the southeast of the country, is Iceland's second-highest peak, and is believed to have the potential to cause serious disruptions to air traffic if there is a major eruption.

The eruption of Eyjafjoell, a smaller volcano, in April 2010 caused travel mayhem.

Iceland's most active sub-glacial volcano Grimsvotn erupted in 2011, forcing the country to temporarily shut its airspace and also sparking fears of a repeat of the Eyjafjoell flight chaos.


http://news.yahoo.com/iceland-raises-volcano-alert-red-eruption-071356871.html

[Buster's Uncle]

Lava Erupts at Iceland Volcano
LiveScience.com
By Becky Oskin, Senior Writer  10 hours ago



This color-coded map shows the earthquakes that have occurred around Iceland's Bardarbunga volcano since Aug. 16, with the most recent tremors in red. The progression of seismic activity shows where the underground lava-filled dike is growing.



Lava is streaming from an eruption north of Iceland's Bardarbunga volcano, the Icelandic Met Office has confirmed. Magma broke through a rift in an older lava flow around midnight local time (about 8 p.m. ET).

The new fissure is 0.6 miles (1 kilometer) long, according to early estimates. The lava field is 5.5 miles (9 km) north of Dyngjujokull glacier, in a region between Bardarbunga volcano and the nearby Askja volcano. Scientists monitoring Bardarbunga's activity are camped near the eruption and confirmed the fiery lava has emerged. Small lava fountains and an orange glow also appeared on the region's live webcams here and here.

Bardarbunga volcano is now at red alert, diverting planes around the area above the eruption. There is no ash cloud from the eruption at this time. Officials also raised Askja volcano to yellow alert. The area around the eruption has been closed to visitors since an earthquake swarm first shook the volcano on Aug. 16.

Askja volcano is 30 miles (50 km) northeast of Bardarbunga. Molten rock is tunneling sideways underground toward Askja from Bardarbunga. The narrow magma intrusion, called a dike, is about 25 miles (40 km) long.

As the leading edge of the dike pushed upwards toward Holuhraun Wednesday (Aug. 27), new cracks appeared on the surface and older fractures in the lava flow expanded, the University of Iceland reported. Holuhraun is a lava flow that erupted in 1797.

Scientists from the Icelandic Met Office and the University of Iceland are closely monitoring activity in the region. Officials flew over the Bardarbunga area on Thursday (Aug. 28) to check for signs of subglacial eruptions. The glacier blanketing Bardarbunga volcano has cracked and sunk over the southeast corner of the caldera rim, a sign of melting underneath the ice.

Three circular crevasses were discovered yesterday during an afternoon reconnaissance flight. Each pit is about 32 to 50 feet (10 to 15 meters) deep and altogether, they form a line about 3 miles (5 kilometers) long.

The meltwater appears to have flooded Grimsvotn Lake, south of Bardarbunga, the IMO said. The lake level has jumped about 16 to 32 feet (5 to 10 m) since its last measurement.

Bardarbunga volcano is buried under the northwestern edge of the huge Vatnajökull ice cap. Scientists must monitor earthquakes, changes in water levels and the glacier's surface to detect a subglacial eruption. The ice in this area is about 1,310 to 1,970 feet (400 to 600 m) thick.


http://news.yahoo.com/lava-erupts-iceland-volcano-131718635.html

[Buster's Uncle]

Iceland lowers volcano alert, says small eruption no threat to aviation
Reuters
By Robert Robertsson and Simon Johnson  12 hours ago



Steam and smoke rise over a 1-km-long fissure in a lava field north of the Vatnajokull glacier, which covers part of Bardarbunga volcano system, August 29, 2014. REUTERS/Marco Nescher



REYKJAVIK/STOCKHOLM (Reuters) - Iceland reduced its aviation warning level to orange on Friday after concluding that a small eruption in the Bardarbunga volcano system that triggered a hours-long red alert actually posed no threat to aircraft.

No sign of ash like that from the Eyjafjallajokull eruption that shut much of Europe's air space in 2010 has been detected this time. But the Icelandic Metrological Office said a no-fly zone in a radius of 3 nautical miles just above the Bardarbunga volcano in central Iceland would remain in effect.

"The small eruption is not a threat to aviation and the published aviation warning area has been cancelled," the Met Office said in a statement.

Iceland's largest volcanic system, which cuts a 190-km (118-mile)-long and up to 25-km-(15.5-mile)-wide swathe across the North Atlantic island, has been hit by thousands of earthquakes over the last two weeks and scientists have been on high alert in case of an eruption.

Reykjavik's Met Office said that just after midnight an estimated 1-km-long fissure eruption began in a lava field north of the Vatnajokull glacier, which covers part of the Bardarbunga system.



Steam and smoke rise over a 1-km-long fissure in a lava field north of the Vatnajokull glacier, which covers part of Bardarbunga volcano system, August 29, 2014. REUTERS/Marco Nescher


While the risk of an ash cloud is highest in case of a sub-glacial eruption, Icelandic authorities for a few hours raised the aviation warning level to red, the highest on a five-colour scale and indicating that an eruption is imminent or under way, with a risk of spewing ash.

The latest eruption was at the tip of a magma dyke 40 km from the main Bardarbunga crater and activity subsided to relatively low levels after peaking between 0020 and 0200 GMT, Met Office seismologist Martin Hensch said earlier.

He said that it was impossible to say how the eruption would develop.

"One of the concerns is that the fissure opens into the glacier but presently there is no sign of that happening," he said, adding that the eruption was 6-8 km from the glacier.

Nick Petford, a vulcanology expert at the University of Northampton in Britain, said fissure eruptions were often spectacular, but relatively low key and often died out in a couple of days. But there could be a sting in the tail, he said.



Steam and smoke rise over a 1-km-long fissure in a lava field north of the Vatnajokull glacier, which covers part of Bardarbunga volcano system, August 29, 2014. REUTERS/Marco Nescher


"Exactly the same thing happened in 2010 with the Eyjafjallajokull volcano," Petford said. "The main eruption was in April, but in March there was a fissure eruption which was a precursor to the much larger eruption."

The Eyjafjallajokull event was particularly disruptive because it pushed ash up to precisely the elevation used by transatlantic aircraft, while prevailing winds propelled the cloud into European air space. The ash was also particularly sticky due to its chemical composition.

Petford said that if the current eruption subsided, scientists would be looking for signs of more quakes deeper under the volcano, which would suggest more magma was welling up, and for any swelling of the volcano that could be measured using GPS.

"Those are pretty clear evidence that large amounts of magma are being stored within the volcano and that's a good indication it will explode."

(Reporting by Simon Johnson, Anna Ringstrom, Niklas Pollard and Alistair Scrutton, editing by Mark Heinrich)


http://news.yahoo.com/iceland-met-office-downgrades-volcano-alert-level-123154092.html