Eyjafjallajokull volcano calms down, but ash production rising
The amount of explosive activity and ash production at the the Eyjafjallajökull volcano increased on Tuesday and was "strong," says a daily report from the Icelandic Meteorological Office and the Institute of Earth Sciences at University of Iceland.
Lava continues to flow northwards and there is now a lava fall down the steep hill under Gígjökull, about two and a half miles north of the crater. Researchers at the site reported blue gas rising from the lava.
The volcano has now built up a cinder cone that is 1,500 by 625 feet large. Lava splashes are being thrown at least 600 feet into the air.
The level of seismic tremors decreased Monday night and by Tuesday morning was down to fairly low levels. However, several earthquakes were detected beneath Eyjafjallajökull Monday night and early Tuesday morning. They appear to be originating deep in the Earth's crust, 8 to 12 miles down.
Icelandic Coast Guard flights on Tuesday estimated the volcano's eruption plume to be 19,00 to 20,000 feet high. It was also picked up on Icelandic Meteorological Office weather radar, and a U.S. National Oceanic and Atmospheric Administration satellite caught it as well.
The ash plume was larger than it was Monday and dark grey in color. The white steam plumes coming up from the Gígjökull outlet glacier, north of the eruption site, are smaller than they were on Monday. The steam plume is created by lava melting the glacier.
The fall of ash, rocks and debris from the volcano locally was heavy on Tuesday. Police at the town of Hvolsvöllur said that in Álftaver and Meðalland, 40 and 50 miles east-south-east of Eyjafjallajökull, people could hardly see nearby farms a mile or so away.
One eyewitness in Fljótshlíð, which is about 5 miles from the eruption site, heard explosions every few seconds. He also reported hearing separate noises from Gígjökull outlet glacier.
By Elizabeth Weise
SourceGeologist answers Iceland volcano questions
Posted on05 May 2010.
IceNews poses some pressing questions about the Eyjafjallajokull eruption to Ari Trausti Gudmundsson, the prominent Icelandic geologist, journalist and author. Ari Trausti's published works include books about volcanoes, nature, environmental protection and astronomy.
What is the volcano doing now: are things getting better or worse?
The Eyjafjallajökull eruption has now (by May 5th) entered its third phase. The first was the lava eruption at the Fimmvörðuháls Ridge. The second was almost a week of rather intense ash production (due to much water from melting ice). The third is characterised by far less ash production (10% or less of the original) but substantial lava flow. The eruption is still somewhat explosive so that ash is carried half as high as before and big lava lumps fly short distances. Two eruption vents are now silent and only the northernmost is active, building up a solid scoria and lava crater within a big ice cauldron in the summit crater of the volcano. The thick lava is tunnelling its way beneath the glacier ice, heading north and downwards to the base of the volcano. Bouts of meltwater flow from the Gígjökull outlet glacier but the discharge is far from being what it was during the first day of the summit eruption.
Are there any indications at all as to how long this eruption might continue?
No, there are none. The registered volcanic tremors are still in good order. The intensity may swing but it seems that the magma flow rate is stable, seen over 2-3 days. The land around the volcano has subsided (according to GPS-monitoring), but less so now than a few days ago. A central volcano eruption, like this one, can continue for weeks or months to come, even years, but the eruption might also "take a break" and then continue. The chosen scenario would be that it abated rather quickly from now; and this could of course happen.
How likely do you think we are to see another eruption in the very near future?
The average eruption rate in Iceland is one eruption every 4-5 years or so. Sometimes a number of them may occur within a decade but a decade may pass with only one eruption, or none. So, we will see an eruption in the future but today there is no indication of where or when.
Is it really safe to visit Iceland any more?
Yes it absolutely is. Think of the last 5-6 decades. It was totally safe to visit Iceland then, despite a number of volcanic eruptions. This time it is utterly safe as well. Everything functions normally and the farming area where damage has been done is not large (but some farms are really struggling and need assistance which they get from volunteers and official institutions). The only snag is that air traffic in Iceland and close-by (not all over Europe or farther away) may have to face some closures for a day or two, if winds are unfavourable, based on that the eruption holds its current phase or lessens. It is downright interesting to witness an eruption, so there is a good reason to visit.
Why is it that the ash chaos seems to be over now even though the eruption isn't?
The ash production is still at hand (and causing troubles close to the volcano) but the power of the explosive activity is much less than before and the fine grained ash is not spread as far as before, partly because the volume is not large and it is not carried high into the air. The lava flow has ample room below the mountain slopes, without causing any havoc and gasses are only problematic very close to the site where meltwater flows from the Gígjökull outlet glacier.
What can we do, as society and as individuals, to make ourselves safer?
The Icelanders have done everything in their power to prevent problems or damage and the monitoring system is good as well as measures taken by the Civil Protection Department. Some 99% of the population is safe and so will every visitor be. The 1% living close to the volcano is safe even if they have to take on the ash fall and fight the consequences. In other countries everyone is safe but governments and transport authorities should address the issue of volcanoes in Italy or Iceland disturbing air traffic in the future.
Is this volcano going to affect the climate?
No, far from it. This eruption (i.e. the productivity and intensity) classifies as a small eruption. Even if it drags on for a long time, no effect on the climate will be noted.
Many thanks go to Ari Trausti Gudmundsson for answering some of the questions we here at IceNews hear asked again and again.
Volcano photo: Anders Peter Amsnæs / www.imagix.dk
Portrait of Ari Trausti: Ferdamalastofa.is
A photo website dedicated to volcanoes
Volcano-watchers, rejoice. The community of volcanic photographers, a small but very dedicated band, is making available online some of its most astounding shots of the Earth's deepest recesses.
A new website, Volcano Picture of the Day, was launched recently. Dedicated to "capturing the power and beauty of volcanoes and geothermal areas," it features an astounding array of recent volcanic eruptions, up close and personal. Check it out here.
By Elizabeth Weise
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