(News and Editorial)
Katla Volcano is located in southern Iceland under Mýrdalsjökull glacier. It is considered the most dangerous volcano in Iceland. This mornings shallow earthquake swarm shows an eruption may be imminent.
5 October 2011: Katla Volcano seismic activity
Webcam at Katla: (copy and paste red link in your browser)
Earthquake swarm after officials confirm eruption at Iceland volcano Katla
05 Oct 2011, by ClickGreen staff
Iceland’s massive volcano Katla appears on the brink of a major eruption just days after officials confirmed they had detected the start of eruptions over the summer.
Measuring devices this morning have picked up a large earthquake swarm, usually a tell-tale sign of a potential volcanic eruption.
The Icelandic Government last month announced it was increasing monitoring Katla, which is one of Europe’s most feared volcanoes, following a consistent and strengthening spike of tremors and quakes.
And last week, officials at the Iceland Meteorological Office confirmed a series of smaller eruptions had occurred in July strengthening fears of an imminent, much larger, eruption.
Evidence gathered by geophysicists showed the magma had risen to the height of the glacier ice above the volcano causing it to melt.
They said the high seismic tremors recorded on July 8 and 9 confirmed Katla had become active and started small eruptions.
Today’s intense swarm of earthquakes started at midnight and dozens of tremors have been recorded – the strongest with a magnitude of 4 at around 3am.
Studies indicate that volcanic activity in Iceland rises and falls so that the frequency and size of eruptions in and around the Vatnajökull ice cap varies with time.
It is believed that four eruptions, that have taken place in the last fifteen years, are the beginning of an active period, during which major eruptions may be expected every two to seven years.
Data provided by the Icelandic Meteorological Office confirms seismic activity has been increasing in the region in recent years, indicating the entry of magma. According to the report, the Hekla volcano is expected to erupt in the near future and an eruption in Katla is also impending.
Katla, which has not experienced a significant eruption for 93 years, is the second largest volcano on Iceland and its eruption will be felt across Europe.
Last year, the country’s president Ólafur Grímsson warned “the time for Katla to erupt is coming close, Iceland has prepared and it is high time for European governments and airline authorities all over Europe and the world to start planning for the eventual Katla eruption”.
Katla is much larger than its neighbouring Eyjafjallajokull – which erupted last year – with a magma chamber about 10 times the size.
Volcanologists warn that if Katla does erupt, the combination of the magma and the large ice sheet covering the volcano could lead to explosive activity and an ash plume for weeks, if not months.
[See my previous post on this topic: ‘Iceland’s Katla volcano showing signs of possible eruption’] One of several articles from that post follow:
Will Iceland’s Katla Volcano Blow Next?
May 8, 2010, modernsurvivalblog.com
Each time following an eruption of Iceland’s Eyjafjallajokull volcano, it’s mighty neighbor, Katla, has erupted shortly afterward. Eyjafjallajokull and Katla are separated by 27 km (17 mi) and are thought to have interconnecting magma channels. Eyjafjallajokull erupted on April 14, 2010.
Katla (named after an Icelandic witch) is known to have erupted 16 times since 930, the last time during 1918. Since then, Katla has been quiet for the longest duration on record. It is overdue, and now that it’s little sister Eyjafjallajokull has erupted, it’s just a matter of time.
Katla itself is 30 km (19 mi) in diameter reaching a height of 1,500 meters (4,900 feet), while the 10 km (6 mi) crater of the volcano lies up to 500 meters (1,600 feet) beneath the Myrdalsjokull glacier on the southern edge of Iceland. Iceland sits directly on top of a split in the earth’s crust of two tectonic plates on the Mid-Atlantic ridge and is a hot spot for volcanic activity with 35 volcanoes around the island.
An eruption of Katla would likely be 10 times stronger than the recent eruption of Eyjafjallajokull and could be disastrous to Iceland with raging floods from the melting Myrdalsjokull glacier, immense depths of volcanic ash, and climate change to regions of the world.
If the eruption is long enough and high enough, ash could be blasted 20 km (12 mi) into the stratosphere and circle the globe blotting out part of the sun from penetrating to earth, and reduce temperatures worldwide. The big question of course is how big would the eruption be and to what extent the global climate change.
We know that when Katla erupted in 1700, the Mississippi River froze just north of New Orleans for example. When Mount Pinatubo erupted in 1991 for 2 days, it dropped temperatures 4 degrees worldwide for a year. Katla on average erupts for 50 days, although the cumulative severity over that time period depends on the force of the eruptions lifting ash high into the atmosphere. We won’t know until it happens.
Although the magnitude of disaster would not be that of a super volcano such as Wyoming’s Yellowstone, the potential is there for a global catastrophe from a worldwide extended deep freeze. Huge crop failures would translate to starvation for some and very high food prices for others. A ripple effect would occur through the already teetering economies of the world.
Since the potential exists for a major Katla eruption, we should prepare ourselves as best we can, knowing that modern society would be disrupted from a disaster of this magnitude (just look at what happened to worldwide air travel and the economic impact from the small eruption of Eyjafjallajokull).