Monday, March 22, 2010

Icelandic Volcanic Eruption Cycle Begins

Let us make this as simple as possible.  History tells us that this eruption will be getting much worse.  How much worse remains to be seen.  However, it is not Hekla 1159 BCE.  Yet history tells us that the immediate effects can act out over a whole year.

This time around, it appears that we will have a ring side seat and ample opportunity to collect data to get a handle on future behavior.

This is just the beginning of the story and it is likely to last for months.

The global warming crowd should note that this is a real mechanism able to perform as a climate modifier. It will be able to cool things out and we will be able to monitor how much.  Perhaps we can then adjust our climate model for prior eruptions. 

This year, the Arctic has appeared to retain warmth most likely from a plausibly warmer ocean, though how is unclear.  The real question is whether the atmosphere has much to do with Arctic sea temperatures.

Iceland prepares for second, more devastating volcanic eruption

March 21, 2010

Iceland is preparing for an even more powerful and potentially destructive volcano after a small eruption at the weekend shot red-hot molten lava high into the sky.

About 500 people were safely evacuated from the land close to the Eyjafjallajokull volcano, which is around 120 kilometres (75 miles) southeast of the capital, Reykjavik. The country's two airports were closed for most of the day and transatlantic flights re-routed to avoid the risk of ash blocking visibility and destroying engines.

After circling the spectacular eruption in a Civil Defence aircraft, Freymodur Sigmundsson, a geophysicist, concluded that the immediate danger was receding and that the lava was flowing along a one kilometre-long fissure.

The original fear was that the volcano had erupted directly underneath the Eyjafjallajokull glacier, which could have caused glacial melt, flooding and mudslides. Instead, the volcano blew inbetween Eyjafjallajokull and the larger Myrdalsjoekull glacier.

However, the danger is that the small volcano is just the beginning and that it will trigger the far more powerful volcano of Katla, which nestles beneath Myrdalsjoekull.

“That has to be on the table at the moment," Dave McGarvie, senior lecturer at the Volcano Dynamics Group of the Open University, said. “And it is a much nastier piece of work.”

Icelanders agree. "This could trigger Katla, which is a vicious volcano that could cause both local and global damage," Pall Einarsson, from the University of Iceland, said.

Tremors around Eyjafjallajokull were first recorded in early March, but precise prediction of volcanic eruption is difficult, even with the high-tech equipment available to Icelandic geologists.

Now that it has happened the only basis for prediction is history — and that does not look good.

"Eyjafjallajokull has blown three times in the past thousand years," Dr McGarvie told The Times, "in 920AD, in 1612 and between 1821 and 1823. Each time it set off Katla." The likelihood of Katla blowing could become clear "in a few weeks or a few months", he said.

Iceland is built on a volcanic rock on the Atlantic's mid-oceanic ridge and it has grown used to eruptions. The southern village of Vik, close to the current eruption, has for centuries had an escape plan in which everybody runs up to the church, which is built on high ground. They know that if Katla erupts flooding will follow.

The island's worst eruption in modern times was in 1783, when the Laki volcano blew its top. The lava shot to heights of 1.4 kilometres and more than 120 million tonnes of sulphur dioxide was released into the atmosphere.

A quarter of the island's population died in the resulting famine and it transformed the world, creating Britain's notorious "sand summer", casting a toxic cloud over Prague, playing havoc with harvests in France — sometimes seen as a contributory factor in the French Revolution — and changing the climate so dramatically that New Jersey recorded its largest snowfall and Egypt one of its most enduring droughts.

Volcano erupts in Iceland near Eyjafjallajoekull
March 21, 2010 · 


From BBC News:
An Icelandic volcano, dormant for 200 years, has erupted, ripping a 1km-long fissure in a field of ice.

The volcano near Eyjafjallajoekull glacier began to erupt just after midnight, sending lava a hundred metres high.

Icelandic airspace has been closed, flights diverted and roads closed. The eruption was about 120km (75 miles) east of the capital, Reykjavik.

About 500 people were moved from the area, a civil protection officer said.

The area is sparsely populated, but the knock-on effects from the eruption have been considerable.

A state of emergency is in force in southern Iceland and transport connections have been severely disrupted, including the main east-west road.

“Ash has already begun to fall in Fljotshlid and people in the surrounding area have reported seeing bright lights emanating from the glacier,” RUV public radio said on its website.

“It was a bit scary, but still amazing to see,” Katrin Moller Eiriksdottir, who lives in Fljotshlid, told the BBC News website.

“The ash had started falling and we couldn’t leave the car.”

 “This was a rather small and peaceful eruption but we are concerned that it could trigger an eruption at the nearby Katla volcano, a vicious volcano that could cause both local and global damage,” said Pall Einarsson, a geophysicist at the University of Iceland’s Institute of Earth Science, Associated Press news agency reported.

That fear of an eruption of a more dangerous volcano in Iceland is more serious than most people realize. The “Gateway to Hell Volcano” erupted there in 1159 BCE.  (Maybe the Devil’s Fry chefs added a little too much barbecue starter to the fire one night.)

21 May 2006

The impact of a volcanic eruption to prehistoric Scotland

Mount Hekla is one of Iceland’s most active volcanoes. It was known to islanders as the “Gateway to Hell” – with good reason. When it erupted in 1159 BCE the effects were felt hundreds of miles away. In Scotland the whole of the west coast was devastated. A sulphuric cloud of ash and acid rain fell on the land, a tsunami raced across the sea and the sun was hidden for years. Such an event immediately changed the lives of the inhabitants of what we now call Scotland and may well have permanently changed their way of life.

Alistair Moffat, author of Before Scotland, has no doubt that when Hekla blew, the west coast inhabitants must have heard the boom and panicked. Moffat thinks they would have been in no doubt that the god’s were angry. The eruption would have been heralded with ferocious electrical storms and the weather would have changed. These people, who we think lived by gathering food from the sea, would have seen their livelihood disappear. The sea changed, crops would have failed and afterwards, for a generation, there was no summer. “We know it happened because of dendochronology. By measuring tree rings in ancient trees you can see that it was a climate-changing event. It shows that for 18 to 20 years there were no summers.”

I suspect those barbecue pits in Hell are being cranked way up these days again, so let’s hope we won’t be soon singing along with our Commerce Secretary…

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