Modest Fissure Eruption Near Bárðarbunga

Source Icelandic Met Office 

 

UPDATED:  See update at bottom.

 

# 9022

 

The on again, off again RED aviation alert for the Bárðarbunga volcano is on again after a 1.5 km long fissure eruption overnight, but right now it is impossible to know just how disruptive this event is likely to become.  That said, this  eruption appears to be much larger than the small fissure eruption on Friday.

 

For now, a long dyke of sub-surface magma stretches north from the volcano to Askja to the north, which is now on Yellow Alert.

 

A tweet from a team on site from the University of Iceland describes the event:

 

An Olympic-sized pool contains about 2500 cubic meters of water, so the estimated lava flow at this time would fill about 24 pools a minute, or 1440 pools an hour.  Impressive, but at this time, this eruption appears to be smooth, non-explosive, and producing little or no ash.

The Icelandic Met Office – which warned yesterday that an eruption appeared more likely – describes the overnight event as:

 

31st August 2014 08:40 - Eruption in Holuhraun observed 05:15

Observation from scientists in the field (05:15): It appears that the eruptive fissure is longer than in the last eruption. It is extending north and south on the same fissure. The eruption is a very calm lava eruption and can hardly be seen on seismometers (almost no gosórói). Visual observation confirm it is calm, but continuous.

 

Several of the webcams monitoring the event I’ve mentioned in the past appear to be offline right now, but you can watch live (from a distance) on this webcam.

 

Seismic activity in and around  Bárðarbunga continues, with a M5.1 reported within the past hour.

We should see an update from the

Scientific Advisory Board of the Icelandic Civil Protection later today.  Yesterday a fissure eruption was deemed one of the more likely scenarios, although an explosive eruption of Bárðarbunga could not be discounted.

Stay tuned.

UPDATE:  1100 hrs EDT

Although weather conditions are hindering observations, the Scientific Advisory board has released the following update:

 

31st August 2014 12:07 - from the Scientific Advisory Board

Scientists from the Icelandic Met Office and the Institute of Earth Sciences and representatives of the Civil Protection in Iceland attend the meetings of the Scientific Advisory Board of the Icelandic Civil Protection.

Conclusions of the Scientific Advisory Board of the Icelandic Civil Protection:

• A lava eruption started in Holuhraun shortly after 04 AM, on the same volcanic fissure, which erupted earlier this week. The fissure is estimated to be 1,5 km long. It was detected on Míla´s web-camera at 05:51 AM. Fewer earthquakes seem to follow the event than in the previous eruption, but more lava is being extruded.
• At 07 AM the lava flow was around 1 km wide and 3 km long towards northeast. The thickness was estimated a few meters, the flow about 1000 m³ pr second.
• Approximately 500 earthquakes were detected in the area and smaller than before. The strongest earthquake, M3.8 was in the Bárðarbunga caldera. Poor weather conditions prevail in the area, which makes detection of smaller earthquakes difficult.
• GPS measurements show continued movements north of Dyngjujökull.
• Gas emissions rise to a few hundred meters above the fissure.
• Weather conditions make it difficult to follow the progression of the eruption, but scientists are in the area, using every opportunity to acquire information on gas and lava outflow.
• Weather conditions do not allow overflight at this time. The opportunity to fly over the area will be assessed later today.

From the Icelandic Met Office:

The Aviation Colour Code for Bárðarbunga is at ‘red' and the code for Askja at ‘yellow'.

I would note that the latest Aviation Color code map has just recently been changed back to Orange.

Icelandic Met Office: Bárðarbunga Update – Aug 26th

 

 

# 9001

 

Although no surface eruption has occurred, seismic activity under and nearby the glacier-covered Bárðarbunga caldera continues to escalate, with the largest event – an M5.7 quake – hitting last night. 

 

It is still highly uncertain what happens next, but given the history of this particular volcano, no one is ready to relax.

 

In today’s update the Icelandic Met Office presents three possible scenarios ranging from a gradual decrease in seismic activity, to a large scale fissure eruption. 

 

26th August 2014 11:50 - from the Advisory Board of scientists

Scientists from the Icelandic Met Office and the Institute of Earth Sciences, and representatives of the Civil Protection in Iceland, attend the meetings of the Advisory Board.

The following points were the conclusion at a meeting of the Advisory Board today:

• Intense seismicity continues. Over 500 events have been recorded since midnight.
• Seismicity continues to migrate northward. Seismicity is now concentrated on the 10 km long tip of the dike extending 5 km beyond the edge of the Dyngjujökull glacier.
• At 01:26 this morning an earthquake of magnitude 5,7 was observed beneath the Bárðarbunga caldera.
• The dyke beneath Dyngjujökull is now thought to be close to 40 km long. Modelling
  of GPS data indicates that about 50 million cubic meters of magma have added to the volume in the last 24 hours.
• There are no indications that the intensity of the activity declining. The following three scenarios are still considered most likely:
• • The migration of magma could stop, accompanied by a gradual reduction in seismic activity.
  • The dike could reach the surface of the crust, starting an eruption. In this scenario, it is most likely that the eruption would be near the northern tip of the dyke. This would most likely produce an effusive lava eruption with limited explosive, ash-producing activity.
  • An alternate scenario would be the dyke reaching the surface where a significant part, or all, of the fissure is beneath the glacier. This would most likely produce a flood in Jökulsá á Fjöllum and perhaps explosive, ash-producing activity.
• Other scenarios cannot be excluded. For example, an eruption inside the Bárðarbunga caldera is possible but presently considered to be less likely.

From the Icelandic Met Office:

The Aviation Color Code remains at the "orange" level.

26th August 2014 06:45 - from geoscientist on duty

Seismic activity continues to be high.

Biggest earthquake in the current swarm was measured this night at 01:26. According to USGS the magnitude was 5.7. The event was localized in the northern/northwestern part of Bardarbunga caldera at 6 km depth.

Most of the seismic activity is close to the rim of Dyngjujokull. The dyke is still migrating to the north and the tip of it is already around 10 km outside of the glacier. Most of the events are at the depth of 8-12 km.

There have been no signs of harmonic tremor.

Barðarbunga Update & Webcams

Source Icelandic Met Office 

 

# 8977

 

Two days ago, in Iceland: Watching Bárðarbunga,  I wrote about the swarm of (mostly small) earthquakes close to Iceland’s second tallest volcano, and the raising of the aviation warning status for the volcano to Orange. Monday morning saw the largest quake – an M4.5 – but since then well over a thousand smaller quakes have continued to rumble.

Yesterday, local authorities – out of an abundance of caution - ordered the evacuation of large areas north of the volcano (see Icelandic Review Alert: Area North of Bárðarbunga Volcano Evacuated), although there are currently no signs of an eruption from the glacier-covered volcano.

 

While  the kind of constant low-level rumbling being detected beneath this volcano often portends an eruption, we’ve seen similar cases where the mountain simply quiets down after a period of time.  Even if there is an eruption, it is impossible to know how big of an event it will be.

 

Nevertheless, Europe and the airline industry – both which was severely impacted by the eruption of Eyjafjallajökull in 2010 – are monitoring these seismic events carefully.  

 

The latest update from the Icelandic Met Office was written last night.

 

A summary of seismic activity, written Tuesday evening 19th August 2014 at 20:00

20.8.2014

Around 1.000 small earthquakes were detected in the Bárðarbunga region from midnight (18/19) until Tuesday evening 19th August at 20:00. All of them were smaller than magnitude 3 and most were located in the cluster east of Bárðarbunga.

 

While the northern cluster close to Kistufell has calmed down significantly following the M4.5 earthquake on early Monday morning, event rates in the eastern cluster are still high. Similar to recent days, two pulses of comparably strong seismic activity have been measured between 04:00 and 08:00 this morning, as well as 16:00 and 18:30 in the afternoon. The cluster east of Bárðarbunga continued to slowly migrate northeastwards today. Events are still located at around 5-12 km depths, no signs of upwards migration has been seen so far.

 

Below is a summary map of all manually revised earthquakes since the onset of the swarm, which illustrates the migration of earthquake activity during the last days. Earthquakes in the map are colourcoded by time, dark blue dots show the onset of the swarm on Saturday, orange dots Tuesday's events until 19:00, light blue and yellow are the days in between. The time scale is days since the onset of the swarm.

Map by Gunnar B. Guðmundsson, Icelandic Meteorological Office.

The following update – dated August 20th – comes from Iceland’s Civil Protection Agency.

 

Summary in English

Last night the National Crisis Coordination Centre was fully activated after a decision was taken to evacuate the highlands north of Dyngjujökull (part of Vatnajökull glacier). The area is now closed and has been evacuated. These actions were taken following seismic activity around the Bardarbunga caldera in the last few days. The area that has now been closed is both large in size and unpopulated  There are still no signs of eruption but these security measures have been taken since it would not be possible to evacuate the area in time should a sub-glacial outburst flood occur from Vatnajökull as a result of an eruption.

At 03.00 the area had been evacuated. A map of the closed area is available at the website of the Icelandic Road and Coastal Administration: http://www.vegagerdin.is/media/umferd-og-faerd/Halendi.pdf In the northwestern part of Vatnajökull glacier the seismic activity is stable, with the main area being northeast of Bardarbunga. Over 300 earthquakes have been detected since midnight. The strongest event was of the magnitude 3.0. Another event happened inside the Bardarbunga caldera and was of the magnitude 2.7.

 
Today The Coast guard airplane, TF SIF, will make a surveillance flight over the area with scientists and representatives of the Civil Protection, if weather conditions allow. Police and ISAR units will enforce the closure of the area. The situation will continue to be closely monitored.

 

While there is little to see right now, three webcams have been placed around the volcano, which will provide live pictures if anything happens on the glacier. 

Iceland: Watching Bárðarbunga

Credit Icelandic Met Office

 

# 8967

 

Over the past 48 hours more than 1,000 (mostly small) earthquakes have been recorded very near Iceland’s largest active volcano and the Icelandic Met Office has raised the aviation alert status for Bárðarbunga  to Orange.   While an eruption is by no means certain, Bárðarbunga has an impressive geologic history, making this swarm worth keeping an eye on.

 

 

First the latest update from the Icelandic Met Office, then I’ll be back with a bit more.

 

• Note

  Intense earthquake swarm continues at Barðarbunga. Presently there are no signs of magma moving to the surface.

• 

Bárðarbunga, Vatnajökull ice-cap, in 1996.

---

Seismic activity at Bárðarbunga persists

18.8.2014

The intense seismic activity that started on 16 of August at Bárðarbunga persists. Very strong indications of ongoing magma movement, in connection with dyke intrusion, is corroborated by GPS measurements. There are currently two swarms: one to the E of Bárðarbunga caldera and one at the edge of Dyngjujökull just E of Kistufell. At 2.37 am on the 18th a strong earthquake (M4) was located in the Kistufell swarm.

This is the strongest earthquake measured in the region since 1996. As evidence of magma movement shallower than 10 km implies increased potential of a volcanic eruption, the Bárðarbunga aviation color code has been changed to orange. Presently there are no signs of eruption, but it cannot be excluded that the current activity will result in an explosive subglacial eruption, leading to an outburst flood (jökulhlaup) and ash emission. The situation is monitored closely.

 

You can read earlier dispatches going back 2 days from the Icelandic Met office at these links:

Activity in Bárðarbunga volcano

Earthquake swarm by Bárðarbunga volcano

 

There is no way of knowing at this time whether Bárðarbunga will erupt, or if it does, how big of an impact it would have.  A major eruption, while possible, is not necessarily the most likely scenario.

 

Roughly 8500 years ago this system did spew forth one of the largest known lava flows of the Holocene (present) era. But the volcano is located in a remote area - far from any large cities - and its biggest threat today may well be from floods due to melting of its thick glacial cap.

 

But we do know that occasionally Icelandic volcanoes have produced significant disruptions – not only locally – but also on a more international scale.

 

In the spring of 2010, the relatively small eruption of Iceland’s Eyjafjallajökull volcano sent thick plumes of ash into the atmosphere, closing many air corridors in Europe and disrupting travel for 6 days, illustrating just how vulnerable our modern world still remains to geologic events.  

 

An estimated 100,000 flights were affected, at a cost of over 1.7 billion dollars.  That said, not every volcanic eruption produces large ash plumes. 

 

In response to the impact of  Eyjafjallajökull  the UK’s National Risk Register For Civil Emergencies – essentially a short list of disaster scenarios (man-made & natural) that the Cabinet Office believe to be genuine threats – added volcanic eruptions in 2013. 

 

This despite the fact that there are no active volcanoes in the UK or Ireland.

 

Their concern stems from the impact of volcanic eruptions outside of their country – most notably, in Iceland. Specifically they cite:

 

Severe effusive (gas-rich) volcanic eruptions abroad – The 2010 eruption of the Eyjafjallajökull volcano in Iceland showed some of the consequences that a volcanic eruption abroad can have on the UK and its citizens. Following consultation with geological and meteorological experts about the potential risks the UK faces from volcanic eruptions in Iceland or elsewhere, the assessment is that there are two main kinds of risk from volcanic eruptions.

The first is an ash-emitting eruption, similar to that in 2010.

The second, which is slightly less likely than an ash-emitting eruption, but which could have widespread impacts on health, agriculture and transport, is an effusive-style eruption on the scale of the 1783–84 Laki eruption in Iceland. This second type of eruption is now one of the highest priority risks in the NRA and the NRR.

 

For those not familiar with the 1783 event –in that year the Craters of Laki in Iceland erupted and over the next 8 months spewed immense clouds of clouds of deadly hydrofluoric acid & sulphur dioxide, killing over half of Iceland’s livestock and roughly 25% of their population.

 

These noxious clouds drifted over Europe, and resulted in widespread crop failures and thousands of deaths from direct exposure to these fumes. There are also anecdotal reports that suggest this eruption had short-term global climate impacts as well.

 

Another eruption of the type and scale seen in 1783 could present an enormous disaster scenario not only to the UK, but to all of Europe.  Earlier this summer the British Geological Survey produced a 123 page volcanic risk report called LARGE‐MAGNITUDE FISSURE ERUPTIONS IN ICELAND: SOURCE CHARACTERISATION outlining the possible risks and uncertainties.

 

While volcanic eruptions are normally a localized (albeit often destructive and traumatic) event, sometimes they can have global impact.  

 

• When Mount Pinatubo erupted in the Philippines in 1991, within a year its aerosol cloud had dispersed around the globe, resulting in `an overall cooling of perhaps as large as -0.4°C over large parts of the Earth in 1992-93’ (see USGS The Atmospheric Impact of the 1991 Mount Pinatubo Eruption).
• Similarly, the explosion of Mount Tambora on the island of Sumbawa, Indonesia in 1815 killed an estimated 90,000 people locally, but its impact was felt around the globe as its ash & gas lowered temperatures across much of the Northern Hemisphere in 1816, contributing to crop failures, weather disruptions, and famine in parts of North America, Europe, and Asia.

 

None of this is to suggest that the recent activity at Bárðarbunga portends a major eruption, or that it poses a significant threat beyond Iceland.  As we saw with Mt. Hekla a little over a year ago, these threats often subside without incident or turn out far less disruptive than originally feared.

 

But we live on a turbulent and geologically active planet, orbiting a variable star, in an area of space littered with rocks and debris.

 

Earthquakes, volcanoes, Solar Flares, tsunamis, violent storms, even incoming space rocks (see Russia: Hundreds Injured By Meteorite Strike) – while relatively rare – do happen.  And often without warning.

 

While most will have limited impact, you just never know which one will touch you and your loved ones.

 

Which is why FEMA and Ready.gov (along with many other state and federal agencies) urge personal, family, business, and community preparedness for all types of natural or man-made disasters, and why this blog will be focusing on preparedness issues during National Preparedness Month (September).