Our Icelandic colleagues have just contacted us. Ásdís Jónsdóttir writes “Just a note to tell you that an eruption has begun in Vatnajökull – it is under the outlet of Dyngjujökull. It started about half an hour ago (at quarter past two p.m.). They are evacuating areas to the north of the glacier (they were partly evacuated earlier).” Gísli Pálsson adds “ It’s now maximum alert, limited air travel around.”
The Icelandic Meteorological Office ha upgraded the aviation alert to red: “Eruption is imminent or in progress – significant emission of ash into atmosphere likely.”
Their most recent report indicates that lava has emerged under the glacier, but that the future progress of this event is still unknown: They list six points (From http://en.vedur.is/earthquakes-and-volcanism/articles/nr/2947)
A small lava-eruption has been detected under the Dyngjujökull glacier.
The Icelandic Coast Guard airplane TF-SIF is flying over the area with representatives from the Civil Protection and experts from the Icelandic Met Office and the Institute of Earth Sciences. Data from the equipment on board is expected later today.
Data from radars and web-cameras is being received, showing no signs of changes at the surface.
The estimate is that 150-400 meters of ice is above the area.
The aviation color code for the Bárðarbunga volcano has been changed from orange to red.
Some minutes ago (14:04), an earthquake occurred, estimated 4.5 in magnitude.
As the earthquakes continue at Bárðarbunga volcano, under Iceland’s largest glacier, local authorities and residents have become increasingly concerned about the risk of outburst floods, though the warning remains at code orange. They recognize that large quantities of water could rush down river valleys if magma should rise to the surface. As a precautionary measure, residents and tourists have been evacuated from two areas north of the glacier. Icelandic authorities have also prepared contingency plans in case floods threaten major hydroelectric facilities.
Another site reports that a number of farmers have rounded up their sheep and horses, who range freely to forage in the summer and early fall. The animals are confined indoors during the long Icelandic winters, where the farmers must supply them with fodder. The farmers and animals alike do not enjoy an early round-up, but the risk of losing animals to floods or to ash-clouds is too great to dismiss.
There have been many earthquakes in the last two days, since GlacierHub last reported on this situation. The first map below, from the Icelandic Meteorological Office, shows how the quakes are tightly clustered. The second, a visualization by Bæring Gunnar Steinþórsson, shows the quakes in three dimensions. His site, http://baering.github.io/, allows viewers to adjust the angle of view and the period that is covered.
As recent reports by Eric Holthaus in Slate and by Dave McGarvie in The Conversation have discussed, there are a variety of types of floods and explosive ash releases that could occur if lava were released at Bárðarbunga, under a layer of ice that is 400 meters thick. it is unlikely that an eruption would disrupt air traffic as seriously as the 2010 event at Eyjafjallajökull. Holthaus modeled a likely scenario of ash transport, should an eruption occur, which shows that it would pass over major airports, but mentions that fewer flights would probably be disrupted, thanks to better forecasts and more effective regulations.
Nonetheless, as the Icelandic anthropologist Ásdís Jónsdóttir wrote in a recent email, “We have to keep in mind that there have indeed been regular eruptions… in the past.” The twelve hundred years of Iceland’s recorded history and the geological evidence from before that demonstrate the great power of Iceland’s volcanoes and glaciers. For the time being the surface of Bárðarbunga remains calm, as shown by these photos that Jónsdóttir took on a recent trip.
Will lava soon hit glacier ice, unleashing an explosion that would spew ash and steam high in the atmosphere? The Icelandic Meteorology Office (IMO) thinks that the probability of such an event in their country has increased. Through Saturday 16 August the risk level had been at code green– a “background, non-eruptive state.” The IMO has upgraded the risk twice in the last two days, on Sunday to code yellow, and earlier today, Monday, to code orange, indicating that a “volcano shows heightened or escalating unrest with increased potential of eruption.”
The responsibility for monitoring such risks falls to the IMO because sub-glacial volcanic eruptions can create vast plumes of material that reach into the atmosphere. This phenomenon is critical for Iceland because of its location on the paths of many flights between western Europe and the East Coast of the US. When the Eyjafjallajökull volcano erupted in this manner in April 2010, flights were cancelled for six days, affecting ten million passengers. The lava was released under a thick cap of glacier, creating a vast plume of ash and steam that was propelled up to an elevation of 9,000 meters. The resulting cloud, presenting a great threat to airplanes, was carried long distances by the jet stream. It covered Norway, Sweden, Denmark, Britain and the Netherlands, as well as large portions of Finland and Germany, and reached far into Russia. On a more local scale, residents and domestic animals had to remain inside for a number of days, and the rivers in the region were flooded with hot water. The ash-fall covered fields and pastures, creating problems for farmers.
The IMO has been monitoring Bárðarbunga, a volcano more than 2000 meters in elevation, located beneath Vatnajökull, the country’s largest glacier. Since early June, they have observed that four GPS stations in the area have shown upward movement in a direction away from the volcano. This movement suggests that a mass of magma (molten rock beneath the earth’s surface) has been expanding upward, closer to the earth’s surface, and displacing the GPS stations.
The IMO have been particularly concerned by what they call a “seismic swarm.” (If you were wondering how to say that in Icelandic, the answer is “skjalftahrina.”) This term, in either language, refers to a cluster of earthquakes. This recent swarm began early Saturday morning and has continued to the present. More than 1400 earthquakes have been recorded, some small, some medium-sized, concentrated near the faults associated with the volcano. These swarms constitute a second line of evidence that an eruption may occur, since such earthquakes can be created by pools of magma as they move upward. The earthquakes in the last 24 hours have been more numerous, more powerful, and closer to the surface—all pointing to an increased likelihood of eruption.
The Icelandic Meteorological Office is monitoring the situation closely. It is coordinating with the local civil defense authority, which has closed roads because of flood risks, and with the International Civil Aviation Organization as well. You can check out a video taken by a brave pilot who flew his plane over the volcano on Sunday. And you can follow this situation at the IMO (http://en.vedur.is/). By the way, the Icelandic word for “weather” is easy for English-speakers—it’s “veður,” pronounced “vethur.”
Read a story on GlacierHub about an Icelandic glacier that does not have a volcano under it, but presents other dangers.