From ESA (zoomed image below the read more line)
New satellite image of ash spewing from Iceland’s volcano
19 April 2010
In this image taken [at] (14:45 CET) by ESA’s Envisat satellite, a heavy plume of ash from the Eyjafjallajoekull Volcano is seen travelling in a roughly southeasterly direction.
The volcano has been emitting steam and ash since its recent eruptions began on 20 March, and as observable, the emissions continue. The plume, visible in brownish-grey, is approximately 400 km long. Envisat’s Medium Resolution Imaging Spectrometer instrument (MERIS) acquired this image on 19 April, while working in Full Resolution Mode to provide a spatial resolution of 300 m.
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Here is a zoomed image
Dartmoor Resident (02:51:35) :
“I hate to defend anything the Met Office computers say in the UK, but I have to say that where I live in Devon in the SW there has been a thin, but noticeable, covering of fine dust on the car for the last three days ”
– Same here in Middlesex. Not only that but the Robins and Blue Tits that were nesting on my house have suddenly disappeared. I realize that this could be due to a myriad of different reasons but (hoping this is not a silly question) is there a remote possibility that something in the air could affect wildlife?
‘This is getting to be a nightmare without end. Several airlines are on the brink of collapse, and stranded passengers are getting increasingly desperate. And, with impeccable Gallic timing, French railway workers have gone on strike. Plans to feed them into a volcano crater, as human sacrifices, have so far been vetoed by the French government’
According to Richard North on: http://eureferendum.blogspot.com/
“Ricardo (00:36:18) :
The ash from the volcano and Saharan dust will both be predominantly fine silica. The melting points therefore won’t be appreciably different, surely?
”
http://scienceblogs.com/eruptions/
This is a good site for detailed answers.
One of the posters said that this volcanic ash was near 57% silicate, and that sahara sand was near pure silicate. Evidently, pure silicate has a higher melting point.
Oldjim: To be fair to the Met Office in this case their models seem to be fairly accurate. The problem seems to be with the ICAO guidelines which set a zero tolerance for ash
There computer model seems to be accurate QED the use of the computer model is held to be “accurate”. That is rubbish, the computer model predicts that planes cannot fly safely in a huge area where there have been test flights that show they can fly safely.
There is also the stupid fact that flying is safer than going by road (particularly long journeys on the wrong side of the road) and so stopping people flying has put people at risk
What is missing from this whole debacle is common sense. The atmosphere is not dust free, it certainly isn’t bird free and flying with or without volcanic risk has a risk attached to it … one that is orders of magnitude lower per mile travelled than hiring a car the other side of Europe and driving three days without proper sleep to get back home.
The appropriate question not: “where is the dust”, but “where are concentrations of dust sufficient to cause serious damage to aircraft”.
For Watt’s sake, what would we all do if the Met Office produced a prediction of where there was a risk of bird strike? Based on their “no tolerance of risk”, all planes would be grounded in all locations bar the South Pole.
At the very least lets get the aircraft back into the sky during the day when the pilots can see whether there are any problems – and by all means have additional engineering inspections of all aircraft after flying through potentially contaminated airspace, but lets stop this ridiculous nonsense about any level of dust must cause all aircraft to be grounded.
If the Eyjafjallajoekull continues to erupt for 2 years we are likely to experience intermittent disruption over Europe’s airspace for some time. However if it sets Katla off, as I understand it has each time in recorded history that it’s erupted, we could be in for far more serious consequences.
I hope there is a serious effort being made to monitor Katla rather than just Eyjafjalla….
http://www.nasa.gov/centers/dryden/pdf/88751main_H-2511.pdf
This is an excellent paper on what can happen at very low ash levels.
Highlights:
1) 0% of modern jets have crashed after entering ash clouds.
2) 8% have had engine flame out.
3) In the case of one of the 4 engines on the Nasa plane, the time before failure was reduced to an estimate 150 hours or less.
4) The damage was not found on the engines until the engine was sent back to the manufacturer to rebuild.
Personal Opinion:
At least 8% of airplanes, and maybe near 100% of planes that fly through low levels of ash will be grounded until a major engine overhaul is finished. I believe the airlines are trapped between two paths to bankruptcy. One, they have no revenue because they do not fly. Two, they fly the plans, and accept that say 1% of the planes will need to be scrapped each day.
Only an Act of God or an Act of Bailout can save them.
No, I would not either.
I am not going to criticize the airlines for being cautious. I am critical for the use of computer models that, if reports are correct, do not accurately track the progress of the ash.
It’s funny how we all casually accept everyday dangers. Statistically, driving to and from work everyday is probably the most dangerous thing we do. But we tend to fear the unfamiliar or uncommon much more. How does flying near the ash cloud compare with the odds of being struck by lightening? How about the chance of experiencing a shark attack?
Regarding the economic cost to the airlines: Commercial air traffic regularly operates in the Middle East and South Central Asia. How does the increase in wear and tear on the aircraft compare with operating in dessert conditions?
Dartmoor Resident (02:51:35) :
‘… a remote possibility that something in the air could affect wildlife?’
they’re taking it reasonably serious in Iceland, based on their previous experiences
http://www.heralddeparis.com/toxic-ash-threatens-iceland-herds/84026
Iceland was formed by volcanism….. The Icelanders are very aware of this fact and the volcanic history. You can be assured that all serious threat volcanoes in Iceland are being closely monitored.
Katla has erupted in every century since the period of settlement at least once or twice per century. So it’s only a matter of when. Some eruptions are larger than others.
OT:
Climate sceptic wins landmark data victory ‘for price of a stamp’
http://www.guardian.co.uk/environment/2010/apr/20/climate-sceptic-wins-data-victory
“Baillie says his data won’t help either way in [the MWP] argument. Last year he and his Belfast colleague Ana Garcia-Suarez, published a study showing that Irish oaks record summer rainfall well, but not temperature. “Keenan is the only person in the world claiming that our oak-ring patterns are temperature records,” Baillie told the Guardian.”
What? I thought tree rings were supposed to be infallible thermometers!
@ur momisugly Enneagram (05:34:00) :
Is good to know that every time the Eyjafjallajoekull Volcano has erupted, a few weeks or months after, the real BIG ONE Iceland volcano, the Katla, has erupted. Here you can find, live, data from sensors at Katla volcano. As you can see its activity is increasing:
http://hraun.vedur.is/ja/Katla2009/stodvaplott.html
Enneagram, that’s the tremmor graph!
The fact is there are no quakes at Katla.
The volcano is still a sleep. No worries for now!
I prefer to be called realist, or empiricist.
And the ones supporting the MET office could be called reality modelers, or even better, charlatans.
Look for quakes here: http://en.vedur.is/earthquakes-and-volcanism/earthquakes/myrdalsjokull/
There are a number of interesting stories in all this.
For instance:
– the MET office is doing all it can but ground based lasers and aircraft to track the ash are at a minimum, and the satellite can’t track ash when it thins; http://news.bbc.co.uk/2/hi/science/nature/8630893.stm
– there isn’t an aviation standard for ash hazards and probably isn’t a health standard either
– activity at Katla has risen 200% in the last 2 days http://scienceray.com/earth-sciences/locals-believe-katla-volcano-in-iceland-near-eyjafjallajokull-will-erupt-in-seven-days/
– this is a minor volcanic event when compared to Katla yet preparation for a Katla event doesn’t seem to be on the books outside and down wind of Iceland
– ash in sufficient concentration can cause power outages (typically in conjunction with rain)
– the computer models aren’t accurate enough for a real world event which is a perfect example of why the climate projections are questionable.
off topic but air related, seems Ozone hole was another conjob too.
http://www.mitosyfraudes.org/Ingles/Crista.html
Paul (3:41)
The difference is that volcanic ash has a lower melting point than silicate minerals.
Desert blown sand is not necessarily silica (SiO2) which is also silicate mineral called quartz, but mat be any or a mix of many different silicate minerals, such as feldspar, mica, pyroxene, etc.
Minerals have a structured arrangement of atoms that takes more energy (i.e. heat) to break apart. Volcanic ash is primarily glass, which has very little, if any, internal order to its constituent atoms, thus requiring less energy to break apart.
Enneagram (05:34:00) :
My understanding is Eyja… has preceeded Katla for several eruption events however Katla does not erupt every time Eyja does.
While I agree we need less chemical hysteria – flouride poisoning to sheep and cattle was evident in the early 19th century eruption. It seems to have been related to flouride buildup on the pastureland rather than direct effects of HF. However- perspective is required- the flouride poisoning was very localized.
“Olafur Grimsson: Eruption is only ‘small rehearsal'”
http://news.bbc.co.uk/2/hi/programmes/newsnight/8631343.stm?ls
As to my earlier post— the threat of flouride is but one of the many risks associated with living in proximity to an active volcano— the dominant risk being too close.
Like a renaissance in travel by rail and sea? Every cloud has a silver lining!
/Mr Lynn
Re: Ricardo (05:30:08) :
“Paul (3:41)
no, there is a significant difference between ‘baked’ and ‘very-recently-baked’ ”
I would guess that the size and porosity would make a difference as the heat would penetrate the ash faster.
On a slightly different issue, I read an editorial by a meteorologist recently proposing that by the time the ash reaches the UK and the rest, the larger particles which can actually hit surfaces in the engines have fallen out and the particles remaining are so light that the airflow through the engine keeps them from making contact; whether they are molten or not. While I think that the decision to close airspace was right in the beginning, the issue needs to be looked at quickly in case we are causing extended chaos without need.
Ref – Agust H. Bjarnason (00:11:33) :
“Hear how Eyjafjallajökull is pronounced in Icelandic:
The name Eyja-fjalla-jökull means:
Eyja: Islands, probably Westman Islands south of the glacier.
-fjalla: mountains
-jökull: glacier…
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Simple people have a way of making the difficult less so. Here’s my contribution to the most confounding aspect of Icelandic Volcanology – “Eyjafjallajökull” equals “Eyekull”;-)
Edbhoy (06:06:05) :
Would it not be prudent, then, to take steps to melt the ice cap over Katla before it might erupt in order to forestall a deadly pall from descending on the EU? Just practicing a little Precautionary Principle.
Re: Jimmy Haigh (23:48:42) :
“I think that the worst thing about the Icelandic volcanoes is that they can spew out hydrofluoric acid. That is seriously nasty sh*t.”
In the one chem report that I’ve seen, [unpronounceable volcano]’s ash is 12.12% calcium oxide, sodium oxide, and potassium oxide. Mixed with water, they form pretty strong bases that can interact with the HF, which turns to hydrofluoric acid with addition of water.
I think they want rain.
Anyone who is familiar with Marcel Leroux’s work could have done better than the Met Office. Ryan Maue superb shot confirms it.