Risk Frontiers, Macquarie University, NSW

and Dept of Geography and Tourism, University of Iceland

21 April 2010

As the recent eruption of Iceland’s Eyjafjallajökull volcano continues, the possibility of further eruptions or other potentialenvironmental hazards must be considered. Australian researcher Deanne Bird has recently returned from a four-year study in southern Iceland looking at the local hazard and risk mitigation and emergency response arrangements. Through this research she has gained extensive knowledge of the eruptive history of Eyjafjallajökull and the neighbouring volcano Katla. Both these volcanoes are located in the municipality of Rangárvallasýsla where she conducted her PhD research.

Although there is significant concern about the current eruption, there is an even greater concern that Katla might also erupt as Katla eruptions have coincided with Eyjafjallajökull eruptions in the past.

In comparison to the two historic eruptions in Eyjafjallajökull (1612 and 1821-1823), Katla has erupted at least 20 times with catastrophic impacts. The historic record of Katla indicates eruptions twice a century, with the last confirmed eruption in 1918.

Like Eyjafjallajökull, Katla is a subglacial volcano. Due to the 400 m of ice covering the caldera, Katla is capable of producing catastrophic jökulhlaup (glacial outburst flood). The jökulhlaup that occurred on 14 April from the Eyjafjallajökull eruption was tiny compared to that which can be generated from a Katla eruption. A worst case scenario from Katla would be a flood with a discharge rate in excess of 300,000 cubic metres per second. In comparison, early reports estimated that the jökulhlaup generated on 14 April from the Eyjafjallajökull eruption was only 3,000 cubic metres per second but still caused major damage to critical infrastructure. This jökulhlaup flooded around the western flank of Eyjafjallajökull, down the river Markarfljót and the national highway still remains closed as a consequence.

The last major jökulhlaup to flood the river Markarfljót from Eyjafjallajökull occurred in 1967. However, this flood was generated by a rock/ice avalanche collapsing onto the glacier and into the proglacial lake of Steinsholtsjökull on the northern flank of Eyjafjallajökull. This flood transported boulders measuring up to 80 cubic metres, 5 km from the rockslide scar.

Katla is renowned as Iceland’s most hazardous volcano due to catastrophic jökulhlaup, tephra and lightning hazards. Heavy tephra fall has been recorded approximately 20 cm thick to distances of 30 km from the eruption site. Also, lighting is known to impact the region within 30-40 km of the eruption site and livestock have been killed as a consequence.

My PhD research revealed that local residents are most fearful of tephra and lightning as they cause significant impacts on important farming communities in southern Iceland. Stories passed down from older generations who had survived the 1918 Katla eruption described the devastating conditions to family and friends. Residents reported that during the height of the eruption they could not see their hand if they held it 30 cm in front of them.

In response to increased seismic activity in Katla since 1999, evacuation and emergency response plans were devised by the Icelandic Civil Protection Office, scientists, local police and rescue teams. These plans, which included response to the Eyjafjallajökull volcano, were tested in a full-scale evacuation exercise in 2006 and the Icelandic Civil Protection Office invited me to observe and participate. Since then, I have been working closely with emergency management agencies and the local communities to improve emergency response procedures.

Since the 2006 evacuation exercise, Icelandic officials have devoted tremendous effort to improve emergency response for volcanic eruptions in southern Iceland. Following increased seismicity in Eyjafjallajökull during February 2010, the Icelandic Civil Protection Office in conjunction with the regional Chief of Police organised emergency meetings with scientists, local police, rescue teams and local residents. My colleague, Gudrun Gisladottir, was asked to present our research and contribute to the ongoing developments to emergency response strategies at these meetings.

Given the recent events in Eyjafjallajökull and high levels of seismicity and crustal deformation around Katla during the past decade, researchers believe that Katla is in an agitated state and an eruption, without prolonged precursory signals, should be expected in the near future.

Figure 1. The volcanoes Katla and Eyjafjallajökull in southern Iceland. The hazard zone represents the possible extent of a catastrophic jökulhlaup (glacial outburst flood) emanating from a Katla eruption. Map produced by Deanne Bird.

————-

If you are a scientist and wish to contribute to this Science Blog, please contact the AusSMC.
Comments received are moderated by the AusSMC and placement cannot be guaranteed.

The opinions expressed in this Science Blog are those of the authors, and do not necessarily represent the views of the Australian Science Media Centre.

Airbus have prepared flight operations briefing notes on volcanic ash awareness.

NASA also have various images available of the volcanic eruption and ash plume.

To view webcam images of the volcano erupting, go to: http://eldgos.mila.is

If you would like to speak to an expert, please don’t hesitate to contact us on (08) 7120 8666 or by email.

Professor Richard Arculus is a volcanologist from the Department of Earth and Marine Sciences at the Australian National University

“The current eruption of Eyjafjallajokull in Iceland is the latest of many that have occurred in historic times along the Southeast Rift Zone of the island.
Iceland is an emergent part of the mid-Atlantic Ridge, along which the North American and Eurasian plates are separating with a high volcanic output. In human terms, the most significant eruption along the Southeast Rift Zone took place during 1783-1784AD at the Laki Fissure – one part of the Grimsvotn Volcano. In addition to ash, a large tonnage of volcanic gases and aerosols was emitted, including sulphur- and fluorine-bearing compounds. The latter killed a large proportion of the Icelandic livestock, and the sulphur ‘haze’ caused not only respiratory difficulties but also a particularly severe local winter in north-western Europe.

The magmas emerging at Iceland are not as rich in dissolved water as those distributed around the Pacific ‘Ring of Fire’, and consequently not intrinsically as explosive. But when lava encounters ground water or in the case of Iceland, glacial ice, fragmentation of the lava occurs forming ash; this type of eruption is called ‘phreatomagmatic’. Ash production continues as long as ground water continues to contact the hot lava, and can persist for months. The ash is wafted by prevailing wind patterns, and distributes according to weather systems.

The ash itself is a hazard to aircraft and jet engines in particular. The material melts and congeals as glass inside the engine causing failure. It is only by good fortune that major loss of life has been prevented. In 1982, a British Airways747 flew into an ash plume from Galunggung Volcano in Java – all 4 engines failed and only through adroit skill and the lucky restart of one of the engines was the loss of the aircraft prevented. A similar incident a few years later to a KLM 747 over Alaska triggered the establishment of a world-wide ash-advisory system.”

Dr Bernie Joyce is an Honorary Principal Fellow at the University of Melbourne

“The second stage of the current Iceland eruption is now at the summit caldera of 1666-m-high Eyjafjöll, and is producing much more ash than the earlier small fissure eruptions, which began on 21st March 2010, near the eastern edge of this large stratovolcano. The last eruption of Eyjafjöll in 1821 lasted just over a year. It is possible that the current ash output which is producing an ash column at least 8 km high may decrease as the water and ice immediately around the new eruption point is dissipated, but ash production could still continue for some time.”

Péter Marosszéky is a Senior Visiting Fellow in the Department of Aviation at the University of New South Wales

“Volcanic ash is primarily comprised of pumice stone which is a very good abrasive. It is also very dry and has no moisture content, resulting in radar not displaying it on the pilots radar screen. The pilot will unwittingly fly into this cloud, resulting in an experience akin to flying into a severe sandstorm. The aircraft’s fuselage, wings, cockpit windows and engines and engine components will be ablated, to the point where the engines will fail to operate due to blocked sense lines. It happened to British Airways many years ago over Indonesia, where all engines ceased to operate on a Boeing 747-200 series aircraft.”

Professor Steven Sherwood, Physical Meteorology and Atmospheric Climate Dynamics at the Climate Change Research Centre, University of New South Wales

“Satellite images show that the plume is not thick or expansive enough to significantly affect climate, though it could produce slightly cooler days in places where it lingers over one spot for the whole day. I’m not sure anyone would notice the effect. It does happen to lie near normal aircraft cruising altitudes (11 km). So unless it intensifies significantly I wouldn’t expect any noticeable impact. Past instances of “years without a summer” and that sort of thing, have been the result of huge injections of material into the stratosphere where it accumulates and lingers for many months.”

Rebecca Patrick is the Manager of the Darwin Volcanic Ash Advisory Centre (VAAC), Australian Bureau of Meteorology

“Volcanic Ash in the atmosphere is a significant hazard to aircraft. The most serious effect is caused by ash melting in the hot section of the engine, and then fusing into a glass-like coating on components further back in the engine, causing loss of thrust and possible engine failure. The International Civil Aviation Organisation has developed a volcanic ash warning system to prevent aircraft from flying into volcanic ash clouds. This warning system includes nine Volcanic Ash Advisory Centres around the world which have responsibility for monitoring, tracking and forecasting the movement of volcanic ash clouds. The Darwin VAAC is responsible for one of the most volcanically active regions of the world, including Indonesia, Papua New Guinea and part of the Philippines.”

COMMENTS FROM THE UK SCIENCE MEDIA CENTRE (PART TWO 20/04/2010)
(Split into science of flight safety, the volcano, Q and A between Channel 4 viewers and UK experts)
(see UK Roundup part one here)

UK Expert reaction to volcanic eruption in Iceland

Science of flight safety:

Chris Yates, Aviation Consultant, said:

“The ICAO’s International Airways Volcanic Watch Operations Group (IAVWOPSG) states: “There is no definition of a safe concentration of ash for different aircraft, engine types or power settings.”

“The ICAO regulation that has prompted this widespread grounding is from experience gained from over 80 incidents between 1980 and 2000 and computer modelling/best guestimate. The airline industry will know this very well and are clearly making the argument that we are being over cautious in grounding all flights.

“Whilst it remains possible to find clear air up above us this doesn’t necessarily mean that there are no pockets of high concentrations of ash at the various flight levels though. I would therefore suggest it’s better to err on the side of caution.”

Stewart John, Fellow of the Royal Academy of Engineering and past President of the Royal Aeronautical Society, said:

“There is no real alternative for assessing the safety of flying without doing test flights. If the situation is desperate then a pilot will know almost immediately as it would be like flying through a sandstorm and the windscreen would be quickly abraded. That’s not the question being asked here though; the dust is so fine that it’s like talcum powder so the issue is of accumulated damage following a few hours of flying.

“Doing the tests is a bit like catching a butterfly in a net, you have to scoop in the air at 500mph and with all the heat of the engines that turns the ash into flecks of molten glass. Afterwards flight engineers have various ways of checking what damage has accrued such as using a borescope to assess the damage to air filters and turbines.

“Unfortunately there’s no real way of checking the build-up of damage in mid-flight and it really has to be done with a plane as you have to get the important factors of speed (up to around 500 mph) combined with the dust and the heat of the engines.

“The airlines are doing the responsible thing at the moment, but we really do need to start thinking of ways round this as we don’t know how long the problem is going to last. I have been asked about planes flying at different heights but this isn’t really a solution. Civil aircraft attain a maximum height of about 40,000 feet and their engines operate optimally at these heights. For every drop of 5,000 feet below this a plane uses about 5-6% more fuel, which is obviously a large amount on a long flight. But just as importantly, you could think that you’re safe flying along at 20,000 feet rather than up at 40,000 where the ash is, only to find that the wind has suddenly dropped and the ash is now at 20,000 feet. It would be a false sense of security so it really is vitally important that test flights are done that cover the entire spectrum of flight patterns.”

The volcano:

Dr John Murray, Senior Research Fellow, Dept Earth Sciences, The Open University, said:

“Contrary to what I said earlier, today the ash has significantly diminished and the ice over the crater itself has melted. This is the stage we have been waiting for: the phreatomagmatic activity (steam explosions due to water being trapped within the erupting lava) will have virtually ceased, and the activity has changed to lava outpouring. Ash may resume at any time, but it is likely to be less pronounced and prolonged than before.

“Hopefully this means that aircraft will be able to fly again shortly, though the meteorologists will have more information on that. The ash is fine grained, so it will take a while to fall to earth, though Ihope the met office will tell us this will happen over a wide area generally further south than the UK.

“The possibility of the activity spreading to the neighbouring Katla volcano is still there, but there are no signs of this happening at present.”

Dr Dave McGarvie, Volcanologist, The Open University, said:

“Yesterday, 18 April, the plume stayed ‘low’ as it was not detected by the radar at Keflavik airport in Iceland. This radar only detects plumes above about 8 km (10,000 feet). Today, 19 April, the plume can be seen (on webcam) to be at low altitude (probably less then 2 km high) and streaming downwind from the vents.

“A tentative interpretation of this is either that the eruption is waning (i.e. lower mass discharge rate), or that there is minimal interaction with ice in the crater and so there is less fragmentation of magma leading to a lower and less buoyant eruption cloud. Visual observations during the day will help us understand what’s going on. But I am mindful of the fact that during the 1821-23 eruption there were periods (weeks-months) when the eruption died down and then started again.

“At the end of the day we have been extremely fortunate in the UK and western Europe to have avoided this disruption for so long. It was inevitable that this would happen, as Iceland has an eruption every 5 years or so. It just so happens that those that have erupted in the past 60 years have not affected us to this extent. But there are plenty of volcanoes that can erupt in a similar (or larger) fashion to Eyjafjallajokull. My sources in Iceland tell me that Hekla has been ‘full’ for months now. And though its recent eruptions have not affected the UK, future ones might well do so.”

Dr David Rothery, Dept of Earth & Environmental Sciences, The Open University, said:

“Webcam images at dawn 05:00 BST this morning reveal a change in character of the summit eruption at Eyjafjallajokull. Small individual explosions could be seen, throwing blocks of incandescent molten lava onto the crater rim. Ash was still being produced, but was dispersing downwind at the altitude of the summit (about 1600 m). There was no high ash column rising above the vent. IF this situation persists, then the high altitude ash cloud will be starved of fresh ash, and will eventually disperse.

“What has probably happened inside the volcano, is that meltwater from the ice-cap is no longer able to leak into the magma conduit, where it has been the main driving force for the explosive expansion that has hitherto (since Thursday) been responsible for the eruption column.

“There is no guarantee that the situation will not revert to what was happening Thursday-Sunday, but there are grounds for cautious optimism.”

(2 webcam images from: http://eldgos.mila.is/eyjafjallajokull-fra-thorolfsfelli/)

Q&A between Channel 4 viewers and UK experts:

What is the best guess for theopening of airspace?

Dr John Murray, Senior Research Fellow, Dept Earth Sciences, The Open University, said:

“Today the ash has significantly diminished and the ice over the crater itself has melted. This is the stage we have been waiting for: the phreatomagmatic activity (steam explosions due to water being trapped within the erupting lava) will have virtually ceased,and the activityhas changed to lava outpouring. Ash may resume at any time, but it is likely to be less pronounced and prolonged than before.”

Dr Dave McGarvie, Volcanologist, The Open University, said:

“Once the highly explosive activity that is generating the very small particles of ash has ended, then perhaps 3-4 days. Maybe less if the wind steers the ash cloud past the UK.”

Can aeroplanes avoid the ash if they fly at lower altitudes?

Dr. Grant Allen, Centre for Atmospheric Science, University of Manchester, said:
“No, for two reasons. Firstly, the ash is slowly descending and Lidar plots recorded around the UK show that the plume is ubiquitous between 2 and 7 km altitude (and occasionally higher in places). Below 2 km the ash is very quickly caught in the turbulence of the surface boundary layer and deposited to ground though jet aircraftare not permitted to fly lower than 2 km due to surface hazards. Secondly, it is not fuel efficient for aircraft to fly lower than 35000 ft on long haul flights – for example, aircraft simplycould not carry enough fuel for transatlantic flights if they flew at less than 5 (~15000 ft) km altitude. Furthermore, our knowledge of the 3-dimensional picture of the plume is too poor to accurately predict or observe such as to enable complex flight plans for aircraft to be developed in a timely fashion.”

Dr John Murray, Senior Research Fellow, Dept Earth Sciences, The Open University, said:

“Aircraft cannot avoid ash at lower altitudes. It all falls to the earth in the end, and the ash was already evident on my daughter’s car windscreen yesterday (see enclosed photograph).”

Dr Dave McGarvie, Volcanologist, The Open University, said:

“No, because the ash is in the lower atmosphere already and slowly drifting down towards the surface. [But if we had better ash-detecting radar that could give real-time 3D imaging of the ash cloud, we could perhaps identify low-risk corridors through which aircraft could fly in relative safety. This is not possible at the moment.]“

Dr Michael J. Branney, Senior Lecturer in Volcanology, Department of Geology, University of Leicester, said:

“Aeroplanes may be able to avoid the ash if they fly at higher or lower altitudes but this particular ash cloud presents two problems. Firstly, the cloud is being blown across the ascent and descent routes of northern Europe, where there are many international hubs. Therefore planes cannot pass through it as they ascend or descend in order to land and take off. Secondly, the ash cloud is a very broadly dispersed, and this would compromise for long stretches of the flight, the opportunity for planes to change their cruising altitude, as they commonly do in order to avoid adverse weather conditions such as turbulence. That’s not good. Finally, ash falls out from ash clouds and so there is likely to be ash at lower altitudes than the cloud, particularly if where moisture helps bring the ash down – moisture in the atmosphere can cause ash particles to stick together forming aggregates that may then fallout quicker as they have a larger size/settling velocity than the individual particles.”

Dr. Guy Gratton, Head of the Facility for Airborne Atmospheric Measurements, Cranfield University, said:

“No, a very large proportion of the ash, and much of that very fine, is between the surface and 6,000ft. Typically light aeroplanes fly at 1,000-3,000ft, and airliners at 20,000-40,000ft.”

Is the CO2 the volcano is spewing out more or less than the cancelled flights would have produced?

Dr Colin Macpherson, Department of Earth Sciences, Durham University, said:

“As yet, there are no direct measurements of the CO2 emission rate for Eyjafjoll eruption. There are preliminary estimates for SO2 emission and CO2/SO2 ratios for the recent eruption of Fimmvörduháls on the flanks of Eyjafjoll1. The composition of the Ejyakjoll eruption is somewhat different (more silica-rich2) than Fimmvörduháls, but assuming similar gas characteristics we can estimate the CO2 flux from Eyjafjoll.

SO2 output of Fimmvörduháls eruption1: 3000 tonnes/day

Relative CO2 content of Fimmvörduháls eruption1: <15%

Relative SO2 content of Fimmvörduháls eruption1: <3%

“This provides a rough maximum estimate for the CO2 : SO2 ratio of ~ 5 : 1. Therefore, the CO2 flux calculated for Fimmvörduháls is 15,000 tonnes/day. This figure is currently circulating on the internet as the same rate for Eyjafjoll. But, the Icelandic Institute of Earth Sciences2 estimate that the magma flux rate over the first 72 hours of the Eyjafjoll eruption was 10 to 20 time higher than that of Fimmvörduháls. Taking the lower limit of 10 times the Fimmvörduháls volume then the CO2 flux of Eyjafjoll would be 150,000 tonnes/day. Until it is possible to accurately constrain the volume of magma erupted from each volcano and to verify whether there are significant differences in the composition of Fimmvörduháls and Eyjafjoll gases, this estimate is subject to very large uncertainty, probably one order of magnitude. However, the CO2 content of the magma inferred from the calculation is 0.25 weight percent, which is reasonable for moderately degassed Icelandic magma.

“There are very large uncertainties on this, because all the observations are preliminary and there are significant assumptions. But I think that it is the best we can do until the volcano settles and direct measurements can be made. This estimate is about 40% of the daily emissions from European aviation.”

Sources:

1 http://www2.norvol.hi.is/Apps/WebObjects/HI.woa/swdocument/1015769/Gas+report+-+Eyjafjallaj%C3%B6kull+2010.pdf

2 http://www.earthice.hi.is/page/ies_Eyjafjallajokull_eruption?99,29

Dr Peter Abbott, School of Geography & Geosciences, University of St Andrews, said:

“I saw this interesting figure on the internet that may be useful. Details of who produced it are on the figure. It was published on the day of the eruption, but I think it nicely demonstrates that the CO2 emissions of the eruption are small fry compared to the planes!” http://www.informationisbeautiful.net/2010/planes-or-volcano/

Dr Dave McGarvie, Volcanologist, The Open University, said:

“As Icelandic volcanoes don’t erupt much CO2 there’s not much CO2 coming out of this particular volcano. We’d need a detailed gas analysis from the eruption site before we could start the number crunching to answer this great question!”

Dr Michael J. Branney, Senior Lecturer in Volcanology, Department of Geology, University of Leicester, said:

“I don’t know the present balance. But of course, there’s no way to prevent volcanoes producing CO2, but in reducing flights we have reduced our carbon dioxide production.”

Why has this caused so much grief to Europe when other eruptions in the world don’t seem to cause a meltdown?

Prof Jon Davidson, Chair of Earth Sciences, Department of Earth Sciences, University of Durham, said:

“The eruption is very ordinary and unremarkable. It’s the fact that it happens to be combined with local weather systems which push the ash over N European airspace.

In other parts of the world ash has certainly interrupted air traffic (e.g. Ruapehu, New Zealand), but in most cases eruptions have not been sustained for long periods and winds have not dispersed them into critical airspaces. Remember that the period of widespread commercial flying is less than 50 years (so we haven’t yet encountered anything like the diversity of volcanic eruption possibilities that might be produced), and its only in the last 30 or so years that we have recognised volcanic ash as a potentially serious threat to aviation (the first international symposium on volcanic ash and aviation safety was in 1991)….AND there have been several incidents of aircraft flying into ash plumes (e.g. Indonesia, Aleutians, with thankfully no casualties).”

Dr Michael J. Branney, Senior Lecturer in Volcanology, Department of Geology, University of Leicester, said:

“It depends where the wind blows the ash. In today’s case the ash cloud is being blown in a broad plume over areas with densely spaced airports and several major international hubs. In some other parts of the world, ash plumes may only blow across one or two airports (e.g. Anchorage, Alaska) which then close temporarily, and passing aircraft can sometimes be re-routed to avoid the ash cloud. In some other parts of the world the ash plume may blow largely across the ocean, where it gradually disperses. In contrast, this cloud is blowing across a large populated land mass.”

How much more/less of thesun’s energy is being blocked out by the ash than is normally blocked out by aircraft contrails?

Dr. Grant Allen, Centre for Atmospheric Science, University of Manchester, said:
“Aircraft contrails actually warm the Earth’s surface, not the other way around. Due to their position in the upper troposphere, contrails act to trap infrared radiation in the lower atmosphere and their net effect over the day/night cycleis to warm the surface. Volcanic ash, however, always acts to cool the surface. Dust and sulphur dioxide which is deposited in the stratosphere reflects solar shortwaveradiation to space and also absorbs/scatters it in the stratosphere before it reaches the surface, thus reducing the energy budget at the Earth’s surface. Furthermore, ash in the stratosphere does not trap infrared radiation and re-emit it back into the troposphere. In summary, if continued for many weeks, the ash will havea cooling effect on the Northern Hemisphere which would last for many months/years, similar to the observed effect of the Mt. Pinatubo eruption in 1991 which is documented to have cooled the Earth’s climate for several years after the eruption.”

Prof Jon Davidson, Chair of Earth Sciences, Department of Earth Sciences, University of Durham, said:

“The ash will not be a long term problem – more likely the SO2 which forms aerosols and could block some incident sunlight (but even so this is still a minor eruption and effects will be negligible to now).”

Naive as the question might be, is there anything we could do to limit the spread of ash?

Dr. Guy Gratton, Head of the Facility for Airborne Atmospheric Measurements, Cranfield University, said:

“Nothing, the main player is the weather system, over which we have no short term control.”

Prof Jon Davidson, Chair of Earth Sciences, Department of Earth Sciences, University of Durham, said:

“Nope. What we could hope for is a way to better track the ash and to determine its density – and know how the ash density maps onto hazard for aircraft, which I don’t think we do.”

Dr Michael J. Branney, Senior Lecturer in Volcanology, Department of Geology, University of Leicester, said:

“Not easily. Volcanic activity cannot be modified by human intervention any more than storms.”

Is it safe for my children to play outside? We live in the Northeast of Scotland.

Dr John Murray, Senior Research Fellow, Dept Earth Sciences, The Open University, said:

“Yes, definitely!!!

Prof Jon Davidson, Chair of Earth Sciences, Department of Earth Sciences, University of Durham, said:

“See the links here for health advice: http://www.ivhhn.org/“

Dr. Guy Gratton, Head of the Facility for Airborne Atmospheric Measurements, Cranfield University, said:

“At present, the UK CAA is in the lead of trying to understand any potential public health risks. Once we’ve got samples from the research aircraft, they’ll be being analysed by an appropriate public health laboratory.”

Dr Michael J. Branney, Senior Lecturer in Volcanology, Department of Geology, University of Leicester, said:

“I shouldn’t worry about playing outside in the UK, with the exception that I understand that some experts have suggested that folk with respiratory conditions (e.g. bronchitis, asthma) may be advised to carry their medication to hand, and remain indoors if they can see falling ash or smell or taste acid or sulphurous smells. However, the concentration of ash is likely to be very low at this distance from the volcano.”

Will the ash from Icelandbe a recurringproblem this year?

Dr. Grant Allen, Centre for Atmospheric Science, University of Manchester, said:

“Possibly, but only if a) the volcano continues to erupt and emit ash due to its contact with water and ice; andb) we continue to see high pressure weatherregimes over the EastAtlanticas we have now, which acts to draw air down from Iceland over the UK.”

Prof Jon Davidson, Chair of Earth Sciences, Department of Earth Sciences, University of Durham, said:

“Depends on two “weathers”- whether the eruption continues and how its intensity (and capacity to fragment and carry ash upwards) varies, and the weather as in the directions that sash is dispersed.”

Dr Dave McGarvie, Volcanologist, The Open University, said:

“Depends on what happens at the eruption site. The conditions that produced the fine-grained ash that is causing the airspace no-fly problem involve an energetic eruption interacting with ice (and its meltwater) and in doing so creating steam explosions which in turn fragment the erupting magma into very small particles of ash that can be transported long distances. Once interactions with ice/meltwater cease the steam explosions cease then so will the production of the very small particles that’s causing the problem. It is normal for eruptions to start energetically (i.e. explosively) and then to become quieter with time, at which point lava flows are effused. So this is likely to happen with this eruption, possibly right now or within a few days. But – and it’s a big but – eruptions like this can have a number of cycles, and so we could see another cycle start with a renewal of explosive activity at any time. Whether this will be as problematic as the current eruption will depend on how energetic the eruption is, the type of magma that erupts and how fast it erupts, and how much interaction there is with ice in the crater. And of course even if there is another eruptive cycle the winds could steer the ash in a direction away from the UK. Yes – lots of variables! But that’s part of the fun and challenge of working on volcanoes.”

“It may be, if the eruption continues in its current style, in which case as weather conditions shift the path of the ash cloud over different regions from time to time it may affect different sectors of airspace. However, it is quite common that this type of eruption becomes less explosive with time, for example if the access of glacier ice and meltwater lessens, in which case less fine ash may get ejected into the atmosphere, and the hazard will reduce to more local (southern Icelandic) proportions.”

What if we all just faced the sky and blew? (Comedian David Baddiel question on Twitter)

Dr. Guy Gratton, Head of the Facility for Airborne Atmospheric Measurements, Cranfield University, said:

“It would make no difference because the lower planetary boundary layer is already (a) very turbulent, and (b) where the large proportion of ash is.”

Dr Dave McGarvie, Volcanologist, The Open University, said:

“You might just get some ash on your face.”

COMMENTS FROM THE UK SCIENCE MEDIA CENTRE (PART ONE 15/04/2010)
(Split into Health, Satellites, Engine, Past events, Atmosphere and Volcano general)
(see UK Roundup part two here)

Health Effects:

Professor Malcolm Green, British Lung Foundation spokesperson says:
“The ash cloud that is presently over Scotland is unlikely to pose a health hazard to our lungs. This is because the cloud is at present high up in the atmosphere and not at ground level. However we would recommend anyone living with a lung condition to carry their medication as a precaution. The British Lung Foundation’s Helpline can also provide advice to anyone concerned about the ash cloud on 08458 50 50 20.”

———–

Prof Ken Donaldson, Professor of Respiratory Toxicology, University of Edinburgh, said:
“Volcanic ash is on the whole not a very harmful material and the ash is currently more than 10km up in the stratosphere, where aeroplanes fly. It will eventually dissipate by dilution in the huge air mass in the stratosphere. The risk to members of the UK public and the population of the world generally from these ash exposures is negligible. Even people who are in the plume of volcanoes where the ash comes to earth and they wade through it like snow, show very little adverse health effects.”

———–

Prof Frank Kelly, Professor of Environmental Health, King’s College London, said:
“While it is unlikely that these emissions will be brought down to ground level over the UK, we are regularly checking our measurements for evidence of an effect of PM10 and PM2.5 concentrations.”

———–

Dr Dougal Jerram, Lecturer in Earth Sciences, University of Durham, said:
“Ash can cause serious health problems but the high altitude of the current plume above the UK means that it is air traffic and not humans on the ground that will suffer.”

Effect on satellites:

John Yates, Chair of the Institution of Engineering and Technology (IET) Satellite Systems & Applications Network, said:
“The 1991 Mount Hudson volcano eruption – one of largest of the 20th century – affected satellite communications systems in Chile. The ash affected satellite communications in Los Antiguos, a town 120km from the volcano, in the same manner as a snow storm can disrupt satellite communications.

“Volcanic ash can also reduce the performance of satellite dishes. The degree to which ash affects the dishes depends on climatic conditions; wet conditions prior to ash falling will cause the ash to stick to satellite dishes – heavy rainfall afterwards will wash it off.”

“The ash cloud is currently at high altitude, but if it was to come towards us and we experience rainfall beforehand, this could cause problems.”

Effect on engines:

Dr Rob Howell, Department of Mechanical Engineering, University of Sheffield, said:
“There are a number of potential issues regarding engine contamination with volcanic ash. One occurs where ash builds up on some of the internal parts of the jet engine, specifically the compressor and changes the aerodynamics of that compressor. It is possible, with enough contamination, for the engine to enter a condition called stall and eventually surge where the engine looses power and can also be damaged.

“Another problem, more often seen in industrial jet engines is where the turbine cooling holes become blocked. This will cause the turbine blades to increase in temperature and fail, potentially destroying the engine. A further problem area is the combustion systems of the engines which can become clogged and again the engine looses power.”

———–

Dr Tim Fox, Head of Energy and Environment at the Institution of Mechanical Engineers said: “Modern jet engines are highly technological machines that work by sucking air in through a large fan and using it in a combustion process to generate thrust. If, for example, foreign objects such as the introduction of large amounts of grit or volcanic ash was to be sucked into the air, this would result in serious damage to the fan blades and internal surfaces of the engine. In turn this would interfere with combustion, ultimately resulting in engine failure.

“In the event of such a failure, which would likely occur to all engines, the aircraft would be forced to make an emergency descent. The best policy if large amounts of volcanic ash are known to be present in the air is clearly not to fly through it.”

———–

Dr David Rothery, Dept of Earth & Environmental Sciences, The Open University, said:
“Ash melts inside the hot engine. This molten glass clogs nozzles and adheres to turbine blades. Pilots’ manuals (revised after 1982 engine losses over Galungung, Indonesia and 1989 over Redoubt, Alaska) advise to throttle back and lose altitude in the event on unanticipated engine power loss. This allows the plan to drop below the cloud, and the cold air drawn into the engines usually shatters the glass and allows the engines to restart. (Previously, pilots would increase engine speed, which made the problem worse). Of course, it is better to avoid flying into an ash cloud in the first place.”

———–

Dr John Murray, Senior Research Fellow, Dept Earth Sciences, The Open University, said:
“The effect on plane engines can be drastic: a thick ash eruption once caused all four jet engines in an airliner to stop together, and on another occasion in Alaska, the windscreens were so abraded by ash and lapilli that they were like ground glass and nothing was visible. The pilots eventually had to land by opening the side windows and looking out.”

———–

Haydn Thompson, from the IET Aerospace Network, said:
“I have actually flown through a volcanic ash cloud over Mexico city when the volcano there unexpectedly erupted. I have also had to clean it off a car there.

“It is very hard and abrasive. It also conducts electricity when it is wet so there is a possibility of shorting out electrics.

“The main hazard though is that an engine may stall and shutdown. There is a very well documented case of an aircraft having its engines shut down after flying through a cloud of ash. Regulations were brought in so that aircraft now have to fly at a lower altitude if ash is present to allow for engine relight – which is what happened to me in Mexico.

“It is not advisable to fly through ash due to the excessive abrasion of materials within the engine.”

———–

Dr David Rothery, Dept of Earth & Environmental Sciences, The Open University, said:
“This is not a dense cloud, and is unlikely to be noticed by people on the ground, though we may have a spectacularly red sunset this evening. However, air traffic restrictions have very properly been applied, resulting in closure of airports and airspace. This is because if volcanic ash particles are ingested into a jet engine, they accumulate and clog the engines with molten glass. In 1982 British Airways and Singapore Airways jumbo jets lost all their engines when they flew into an ash cloud over Indonesia, and a KLM flight had a similar experience in 1989 over Alaska. On each occasion, the plane fell to within a few thousand feet of the ground before it was possible to restart the engines.

“As a result of those experiences, emergency procedure manuals for pilots were changed. Previously, when engines began to fail the standard practice had been to increase power. This just makes the ash problem worse. Nowadays, a pilot will throttle back and lose height so as to drop below the ash cloud as soon as possible. The inrush of cold, clean air is usually enough to shatter the glass and unclog the engines. Even so, the forward windows may have become so badly abraded by ash that they are useless, and the plane has to land on instruments.”

See http://www.metoffice.gov.uk/aviation/vaac/data/VAG_1271309704.png for forecasts of the ash cloud at 06:00, 12:00, 18:00 and 24:00 (midnight) today issued by the UK Volcanic Ash Advisory Centre (part of the Met Office).

———–

Stewart John, a Fellow of the Royal Academy of Engineering and former President of the Royal Aeronautical Society, said:
“An erupting volcano can spew out a great mushroom cloud of ash that rises thousands of feet into the sky where the fine white ash poses a serious hazard to modern jet engines. It’s like a very dense, abrasive talcum powder and within minutes of being ingested into an engine it will clog up the miniscule air cooling holes and stop the engine.

“No airline would run the risk of trying to fly in such conditions – a Boeing 747 was nearly lost over Indonesia in the 1980s after accidentally flying into an ash cloud, which stopped all four engines. Mercifully the pilot managed to restart one engine and land the plane.”

———–

Dr David Kerridge, Head of Earth Hazards at the British Geological Survey, said:
“Volcanic ash clouds are made up of small abrasive particles that can clog up jet engines and stop them working. Planes are either re-routed or grounded when there’s a danger of flying into ash clouds to ensure the safety of passengers and avoid very costly damage.”

———–

Dr Michael Branney, Senior Lecturer in Volcanology, University of Leicester, said:
“Volcanic ash is not good to plane engines: firstly it is highly abrasive and can scour and damage moving parts; secondly, if it enters a jet engine the intense heat of the engine can fuse it to the interior of the engine with a caking of hot glass, which ultimately can cause the engine to cut out completely. Pilots are trained in how to deal with this emergency should it occur, but its best to avoid the encounter altogether, which is why flights crossing the path of the ash plume are being cancelled. This is a sensible precaution.”

Past events:

Dr Dougal Jerram, Lecturer in Earth Sciences, University of Durham, said:
“Currently this is a relatively small eruption, with little health risks, but in the past Europe has been affected by plumes of ash from Iceland that have been very significant. An interesting fact is that one of the most influential eruptions in historic time was the 1783-1784 from Laki in Iceland where an estimated 120 mio. tons of sulfur dioxide were emitted: approximately equivalent to three times the total annual European industrial output in 2006. This outpouring of sulfur dioxide during unusual weather conditions caused a thick haze to spread across western Europe, resulting in many thousands of deaths throughout 1783 and the winter of 1784.”

———–

Prof Bill McGuire, Professor at the Aon Benfield UCL Hazard Research Centre, said:
“It is not particularly unusual for ash from Icelandic eruptions to reach the UK. The most notable occasion occurred in 1783, when a cloud of ash and sulphurous gases from the major Laki eruption lay across Europe from the summer of that year and into 1784. The cloud resulted in elevated summer temperatures and resulted in poor air quality that caused a significant increase in mortality in the UK and elsewhere in Europe. Such a large eruption occurring today would have the potential to severely affect air travel at high northern latitudes for six months or more. In relation to the current eruption, it is worth noting that the last eruption of Eyjafjöll lasted more than 12 months. If this eruption has a similar duration then ash could periodically present a problem in UK air space.”

———–

Dr Colin Macpherson, Department of Earth Sciences, Durham University, said:
“Eyjafjallajökull has been active at least 12 times over the past 800,000 years, with the previous eruption lasting two years (1821-1823).”

———–

Atmosphere:

1. What might be the impact on farming?
Dr. Thor Thordarson, Volcanologist, University of Edinburgh, said:
“The likelihood that this eruption has any impact on farming or the environment is negligible, mainly because the magma output from this eruption is so small.”

———–

2. Are there any plans by scientists to use shutdown to test air quality etc, like post 9/11?
Dr. Thor Thordarson, Volcanologist, University of Edinburgh, said:
“Someone else has to answer this one, but I wish it would be done especially since I like to get an ash sample from the plume.”

———–

3. How much material has been ejected by the volcano?
Dr. Thor Thordarson, Volcanologist, University of Edinburgh, said:
“Not known at this stage, but some remote sensing researchers may be able to provide an estimate from thermal images. Otherwise we will have to wait until we have mapped and sampled the tephra fall out.”

———–

Dr Clive Oppenheimer, Reader in Volcanology, University of Cambridge, said:
“There’s 0.5 cm of ash on the ground in the farmland areas around the volcano and the access to the area is difficult because of the glacial floods that accompanied the eruption yesterday. As soon as ash samples reach Reykjavik they will be able to make some further assessments about the nature of the eruption and the risk the ash poses to farming and agriculture. One of the key concerns on the ground is the level of fluorine carried on the ash. Many livestock have died in previous Icelandic eruptions through fluorine poisoning.”

(For graphics I would check the USGS volcanic hazards website – all their material is public domain)

———–

Dr Michael Branney, Senior Lecturer in Volcanology, Department of Geology, University of Leicester, said:
“The level of the ash plume is currently between 6 and 11 km high and it has already advanced over northern Britain and across to Scandanavia (I do not know the mass or volume of todays eruption).”

———–

Dr Sue Loughlin, Head of Volcanology at the British Geological Survey, said:
“Ash has been reported at 55000ft over northern Scotland. Where it goes now depends on wind speed and direction.

“This eruption on Eyjafjallajokull in Iceland began on 20th March 2010 on the NE flank where there is no ice and it was very small. The volcano is now erupting from the central crater which is under the ice cap. It is melting the ice causing significant flooding around the volcano.

“The last eruption was in 1821-1823 followed in 1823 by a much bigger eruption of Katla which is next to Eyjafjallajokull.”

———–

1. How long is it going to take this ash plume to disperse?

Dr David Rothery, Dept of Earth & Environmental Sciences, The Open University, said:
“The London Volcanic Ash Advisory forecasts suggest that ash will drift south over England until at least midnight.”

Dr John Murray, Senior Research Fellow, Dept Earth Sciences, The Open University, said:
“The truth is we don’t know yet: it could all be over by tomorrow and have no serious effect, on the other hand if it’s like the Laki fissure eruption it could be serious and continue for months.”

2. Is this a one-off injection of ash into the upper atmosphere or is it likely to continue disrupting air travel for weeks or months ahead? “

Dr David Rothery, Dept of Earth & Environmental Sciences, The Open University, said:
Probably a one-off. The major explosive episode of the eruption appears to over, but a repeat cannot be ruled out.”

Dr John Murray, Senior Research Fellow, Dept Earth Sciences, The Open University, said:
“The truth is we don’t know yet: it could all be over by tomorrow and have no serious effect, on the other hand if it’s like the Laki fissure eruption it could be serious and continue for months.”

3. Is there enough ash in the atmosphere to affect weather/climate?

Dr David Rothery, Dept of Earth & Environmental Sciences, The Open University, said:
“No. The total volume is relatively small.”

Dr John Murray, Senior Research Fellow, Dept Earth Sciences, The Open University, said:
“The truth is we don’t know yet: it could all be over by tomorrow and have no serious effect, on the other hand if it’s like the Laki fissure eruption it could be serious and continue for months.”

4. Is any of the ash going to reach the Earth’s surface as dust?

Dr David Rothery, Dept of Earth & Environmental Sciences, The Open University, said:
“Yes, or more likely washed down in rain. However, the density of ash-fall in UK and mainland Europe will probably be too slight to be noticed, excerpt that sunset/sunrise might look redder than usual because of ash in the sky.”

Dr John Murray, Senior Research Fellow, Dept Earth Sciences, The Open University, said:
“Some of the ash will reach the surface, the Met Office are predicting the cloud to start passing over southern England in an hour or two’s time.”

———–

Dr Peter Abbott, School of Geography & Geosciences, University of St Andrews, said:
“An explosive volcanic eruption in the South of Iceland on Tuesday injected a large amount of ash high into the atmosphere and the prevailing wind conditions have transported it over northern Europe and caused significant disruption to air travel. A event of this nature is not a regular occurrence as it requires a combination of specific volcanic conditions in Iceland and atmospheric conditions over Europe. Our study of ash layers in the geological record shows that the transport of ash over the United Kingdom will occur approximately every century.”

———–

Anja Schmidt, School of Earth and Environment, University of Leeds, said:
“At the moment there is a north westerly air flow from Iceland into northern parts of the North Sea, thus most of the ash will be transported to Norway and central Sweden. Britain will be affected as well, though I don’t expect it to be as strongly affected as Norway. The weather forecast indicates that the high pressure system over the Atlantic remains stationary so a north westerly flow will continue bringing fine volcanic ash into Norway, Britain and it might even affect Denmark and northern Germany [if the eruption continues].

“As with most volcanic eruptions it’s hard to predict how long the eruption will last – from historical eruptions of Eyjafjallajokull we know that the previous one in 1821 lasted for more than a year. As long as magma continues melting its way through the glacier I’d expect further phreatic eruptions injecting steam and ash into upper parts of the atmosphere.

“If the eruption continues injecting fine ash and volcanic gases into the atmosphere over the coming months then it might affect weather or even climate. Whether the eruption has an effect on climate will depend on how long it is going to last and on the injection height of the gases and ash. At the moment the eruption cloud reaches around 22,000 feet which is high enough to affect aviation but is unlikely to be high enough to have a strong effect on the climate system. In terms of weather phenomena I’d expect some bright red sunsets during the next couple of days in Northern Europe.

“Most of the larger ash particles are settling out in and around southern Iceland, close to the eruption source. Only fine ash particles will be transported over great distances.”

———–

Dr Michael Branney, Senior Lecturer in Volcanology, University of Leicester, said:

How long is it going to take this ash plume to disperse?
“A volcanic ash plume can take days to months to disperse, depending on its size and height. If it’s not too high in the atmosphere rainfall can help bring down the ash relatively quickly.

“Although the plume is already starting to disperse, how long it persists depends on how long the explosive eruption continues. In this case it’s too early in the eruption to be sure how long ash will continue to be forced into the atmosphere. Volcanic eruptions can last anything from a few hours to several months, in rare instances they can last for years but this last scenario is the least likely.”

Is this a one-off injection of ash into the upper atmosphere or is it likely to continue disrupting air travel for weeks or months ahead?
See answer to the above.

Is there enough ash in the atmosphere to affect weather/climate?
“Icelandic eruptions are capable of affecting weather. Historic Icelandinc eruption have affected the weather significantly across northern and central Europe, but in most cases the effects are more local.”

Is any of the ash going to reach the Earth’s surface as dust?
“Yes. Volcanic ash is made of tiny, abrasive particles of volcanic rock. It will all eventually fall back to the ground. Close to the volcano this look like a grey layer of dark sand, but further from Iceland it may appear as a thin layer of grey dust, rather like the dust you sometimes see on your car when the wind blows from the Sahara. Atmospheric moisture helps bring down the finer dust-sized particles.”

———–

Geoff Dollard, Knowledge Leader for Air Quality at energy and climate change consultancy AEA, said:
“Our current information tells us that the volcano’s plume will not harm health in the UK. If the eruption continues then forecast meteorology indicates that the flight disruption could continue for up to another 24 hours. AEA’s air pollution forecasting team have been watching the Eyjaföll volcano for some weeks. At a special forecasting team meeting convened this morning, forecasters studied satellite and model evidence from NASA, EUMETSAT and other source. This evidence indicates that the volcanic dust will not touch the ground, but remain at about 6km altitude, passing over the UK.”

———–

Volcanology:

Prof Steve Sparks FRS, Director Of The Bristol Environmental Risk Research Centre at the University of Bristol, said:

“The ash eruption seems to have started last might and the column height is about 4 to 6 km, which means around 100-200 cubic metres per second of ash erupted, because there is a well known relationship between heat flux and plume height. This in turn means 10 million cubic metres so far and about 3 billion kilograms of ash. My Icelandic colleagues think it may go on another 2 or 3 days and the activity should gradually die down. The injection height is in the troposphere.

“The volcano has been erupting for about a month but in the gap between the Eyjafjallajökull and Mýrdalsjökull ice caps. This has been mostly lava and mild explosive eruptions. This vent stopped yesterday and then the vent switched to under the western ice cap (Eyjafjallajökull). The eruption became much more explosive due to the eruption into ice. The ash is reported to be very fine even in Iceland. The reported sulphur dioxide (SO2) fluxes have been about 3000 tons per day.”

———–

Dr Mike Burton, Senior Volcanologist, Italian National Institute for Geophysics and Volcanology, said:
“The current activity on Eyjafjallajökull volcano, Iceland, is the second phase of an eruption that began on 21st March 2010. The first phase was focussed on the pass know as Fimmvörduháls, which lies between the glaciers covering the nearby volcanoes of Eyjafjallajökull and Katla. It was a lateral eruption of Eyjafjallajökull, and, thanks to its location between the glaciers, it produced a largely ash-free eruption, with abundant lava flows. I conducted measurements of the gas emissions from the Fimmvörduháls eruption on 1st and 2nd April, in collaboration with Icelandic scientists from the university of Reykjavik, and a report summarising our findings was published on their website: http://www2.norvol.hi.is/Apps/WebObjects/HI.woa/swdocument/1015769/Gas+report+-+Eyjafjallaj%C3%B6kull+2010.pdf

“After 9-10th April volcanic activity at Fimmvörduháls rapidly reduced, and probably stopped on 12th April. After a brief pause a new eruptive phase began around midnight on the night of 13th/14th April. This new phase was more powerful than the previous one and the highly pressurised magmatic intrusion punched up through the volcano to erupt close to the glacier-covered summit. The initial result of the eruption was a rapid flooding of the area around Eyjafjallajökull, as ice in proximity to the erupting magma melted. Today, on 15th April, the production of flood water has greatly reduced, probably because the eruption has melted most of the ice directly on top of the volcanic activity. With the ice cover removed magma is erupting into the atmosphere, and the abundant water that surrounds the eruptive site is interacting explosively with the magma to produce the abundant ash which poses a threat to air traffic in northern Europe. When the local supply of melt water runs dry the ash production may well be strongly reduced, even if the eruption continues. So, in terms of the affect on air traffic, the eruption will continue to be a threat due to voluminous ash production as long as there is magma-water interaction.

“As soon as the eruption develops into a pure magmatic phase we hope to return to the volcano to conduct further measurements of the gas release in collaboration with our Icelandic colleagues. These measurements will be of great interest, as we’ll be able to compare the flux and composition of the gas emissions from the current summit eruption with those we collected in early April, and thereby gain insight into the nature of the magmatic systems powering both eruptive phases.”

———–

Dr Michael Branney, Senior Lecturer in Volcanology, Department of Geology, University of Leicester, said:
“As hot basalt magma (liquid rock and dissolved gases) rises to the Earth’s surface, and the gases dissolved in it expand driving the upward flow even faster (like opening a giant Champagne bottle and it all spurting out), ultimately ripping the magma apart into a myriad of incandescent particles. This ‘volcanic ash’, entrained in hot gases may exit the volcano as an upwards-directed supersonic jet. Cold air from the surrounding atmosphere gets sucked into this rising jet, and the hot particles in the jet heat up the cool air, causing it to v. rapidly expand until the erupting mixture becomes less dense than the lower atmosphere – this causes the column to loft upwards through the atmosphere by buoyancy, a bit like a smoke plume above a huge bonfire. The atmosphere gets more rarefied upwards, and the volcanic ash plume eventually finds its level of neutral buoyancy, and then spreads out laterally. It is also blown by the strong winds at this height, in this case across the Shetland isles to the UK and Scandinavia.”

———–

Dr Dougal Jerram, Lecturer in Earth Sciences, University of Durham, said:
“Volcanic ash is made up of tiny particles that are created when bubbles break due to gasses in a volcanic eruption. Eruptions which are charged with gas start to froth and expand as they reach the surface which results in explosive eruptions and this fine ash being sent up into the atmosphere. If it is ejected high enough into the atmosphere, it can reach the high winds and be dispersed around the globe e.g. from Iceland to Europe. These high winds are exactly where the airplanes cruise and that is why they are not allowed to fly.

———–

Prof Geoff Wadge, Environmental Systems Science Centre, University of Reading, said:
“Eyjafjoll last erupted in 1823 and continued for a year. That is not to say that it will do so again, but it is a possibility that future disruptive ash events will occur.

“Icelandic eruptions have produced ash that has affected aviation sevarl times in thepast – last in 2004 with the Grimvotn eruption.

“There are a series of Volcanic Ash Advisory Centres that cover the whole globe and the one that monitors the North Atlantic ad Iceland in particular is run by the Met Office based in London. Essentially they can track the location and density of the ash in the atmosphere using infrared sensors on satellites that give data every 15 minutes.”

———–

Dr David Rothery, Dept of Earth & Environmental Sciences, The Open University, said:
“The eruption of the Eyjafjoll volcano in southern Iceland, which climaxed yesterday with flooding and tall eruption column driven by expanding steam, distributed fine rock particles known as ‘volcanic ash’ as high as 11 km into the atmosphere. This ash cloud is now drifting with the high altitude winds. The main mass is over Scandinavia, but it is also over the north of Great Britain and is likely to spread south over the whole island by the end of the day.

———–

Prof Bill McGuire, Professor at the Aon Benfield UCL Hazard Research Centre, said:
“The 1600m high Eyjafjöll volcano (also known as Eyjafjallajökull) is located in southern Iceland, immediately west of Katla volcano. Eyjafjöll is an elongated, ice-covered volcano topped by a 2.5 km wide summit caldera. The volcano appears to have been relatively inactive over the last 10,000 years, and the sole historical eruption, prior to this year, occurred in 1821.

“The current eruption started on 20 March 2010. Following a pause in activity, a new vent opened on 13 April generating a column of ash several kilometres high and causing melting of overlying glacier ice. This resulted in the formation of glacial outburst floods that closed roads and caused some structural damage. 700 people were evacuated from the area as a precaution.

“The ash cloud generated by the ongoing eruption is currently to the north of Scotland, and heading south at a height of about 18 km. It is currently expected to move across Scotland and northern England by 13.00 BST. As of 10.00, Scottish and northern airports are closed and London’s airports are expected to close later in the day.”

“Volcanic ash is silica-based material and highly abrasive. It is capable of causing major damage to aircraft through clogging engines and causing them to flame out, and by scouring windscreens so as to make them opaque. Over the past few decades there have been more than 80 encounters between civil aircraft and ash clouds, resulting in a number of situations wherein crashes have only narrowly been avoided. Most notable was an encounter in 1982 between a BA 747 and an ash cloud from Galunggung volcano in Indonesia. Ash in the engines resulted in all four failing, causing the plane to fall 7,000 m before the engines could be restarted. Even then, landing was made extremely difficult by the fact that the windscreen had been scoured opaque by the ash.”

For a satellite image: http://oiswww.eumetsat.org/IPPS/html/MSG/RGB/ASH/ICELAND/

———–

Dr. Thor Thordarson, Volcanologist, University of Edinburgh, said:
“Since the New Year, unrest in the form of seismic activity and inflation has intensified beneath the Eyjafjoll volcano in South Iceland and eruption(s) has been expected. The 20.03.2010 – 12.04.2010 event was a small basaltic fissure eruption on the lower east flanks of the Eyjafjoll volcano, whereas the one that began this morning emerged from fissures (vents) within the summit crater and extended just outside its southern rim.

“The associated seismic activity indicates that these two events came up through separate conduit systems. The current one was situated further west, directly beneath the volcano summit and most likely is erupting magma of more evolved composition (i.e. higher in silica) than its immediate predecessor. As the new eruption site is beneath the glacier that caps Eyjafjoll volcano this has resulted in substantial melting of ice. Earlier today fairly large flash floods cascaded down some of the outlet glaciers and the rivers that drain from them. Consequently, access to the volcano as well as nearby main roads (including Highway 1) and evacuation of residence has been implemented. The situation will be closely monitored and managed by the Civil Defence and associated authorities.”

———–

Dr Dave McGarvie, Volcanologist, The Open University, said:
“This wasn’t unexpected because the eruption that took place last month between two ice caps has diverted off to the east and erupted again at the current site. It is essentially the same eruption which has found a new pathway to the surface. The eruption this time is coming through 150 metres of ice, melting it and pouring water down to the north – the rivers will be carrying as much water as they would in the peak of a Spring melt.

“The eruption can now develop in three ways:
1. It will melt ice, go on for a time and then die out, and nothing more will happen.
2. It will stimulate a larger eruption which will release a new batch of magma – this has happened in the past and is the worst case scenario. In this instance, the resulting ash cloud would disrupt international travel with flight paths being diverted.
3. It stimulates lava flow to come out which will melt a canyon in the ice to low lying regions. This previously happened in the ninth century.
“Iceland is extremely well prepared for all kinds of scenarios around this particular volcano.”

———–

Dr Andrew Bell, School of Geosciences, University of Edinburgh, said:
“In both a global and an Icelandic context, this is a relatively minor eruption, involving only small amounts of magma. This is a very typical eruption for Iceland, made slightly more notable by the location under the glacier, and the current meteorological conditions. As has happened during previous eruptions of Eyjafjöll, there is a possibility that the current eruption could evolve into a more explosive event, involving a different composition of magma, or could lead to activity at the neighbouring volcano, Katla. Both scenarios could result in further ash production and disruption to air traffic. It is very difficult to say how long the current eruption could last; it is quite possible that activity (and disruption) could continue for weeks or months.”

———–

Dr Colin Macpherson, Department of Earth Sciences, Durham University, said:
“Eyjafjallajökull is one of many volcanoes that pepper the boundary between the tectonic plates that move North American and Europe apart from one another at 2 centimetres per year. Most of these volcanoes lie 2-4 kilometres beneath sea-level but at Iceland the volcanoes have built land. Rock beneath the diverging tectonic plates melts slowly and builds up magma bodies over hundreds to thousands of years. When the magma rises to the surface in the boundary zone a volcano will erupt.

“Eyjafjallajökull has been active at least 12 times over the past 800,000 years, with the previous eruption lasting two years (1821-1823). Many Icelandic volcanoes, including Eyjafjallajökull, are covered by icecaps and the interaction between magma and lots of very cold water can lead to explosive eruptions and catastrophic floods. The rapidly chilled magma fractures into solid, glassy fragments that are carried upwards in the eruptive column and then dispersed according to the prevailing wind direction. This can lead to stark contrasts in the effects of the erupted ash on different sides of the volcano. The melted icecap pours off the flanks of the volcano causing floods that can transport large pieces of ice and rock.”

The views expressed below are the personal opinions of the experts named here. They do not represent the views of the AusSMC or any other organisation unless specifically stated.

John Dartnall ME(research) BE(mech) BSc(maths&comp), Lecturer, Mechatronics and Intelligent Systems, Research Director, Heliseal and Tyteam projects, Faculty of Engineering, University of Technology, Sydney

“The potential for solar cars has always been more as racing cars – they work best as slender light cars with the cells on the roof . We’re used to heavier more ordinary vehicles so if we were ever going to develop a day to day application for solar in cars it was always the idea that you develop a car that you can park under a roof that’s covered in solar cells and the car can plug into that energy and recharge while you’re at work and the car’s doing nothing .

There are things happening with boats – solar is well suited to boats. A catamaran for example with a flat deck area and a huge roof covered in photovoltaic cells – that’s a very practical application, and that kind of thing is happening now.

However Australia is now lagging in developing solar technology whereas once it was a leader. There’s probably a lot more progress with solar cars and solar boats in other countries around the world, China in particular, than there is here. Having said that though there is a much greater public awareness developing of how much energy we do consume and that can only lead to more demand for these technologies to be developed further”.

Professor Stephen Lincoln from the Dept of Physics and Chemistry at the University of Adelaide

“The solar car race is more symbolic than anything but it’s very important because it demonstrates to the public quite unequivocally that energy from the sun can actually power a car.

Solar technology is still quite primitive compared to what it will be 20 years from now. Most current solar cells only capture 20% of the energy available to them as they work in a narrow wavelength band. There are cells being developed now which can catch a much wider wavelength range of sunlight and achieve 40% efficiency, but 20 years from now they will be far more efficient.

However in reality solar power alone is never going to be a solution to directly power cars of any size – after all it’s going to be very difficult to drive a solar car at night. What is far more likely is that solar energy will be used to produce hydrogen which can then power a car. So when looking to the future we should look at where this kind of research is going. For example in the the US (using technology developed originally in Australia) they are working towards developing a gigawatt power station entirely powered by solar. Also we should remember that the people working on solar cell technology and on the race are mainly still in their teens and twenties and they will be the ones that solve these problems”.

Dr Richard Corkish is Head of School at the School of Photovoltaic and Renewable Energy Engineering University of New South Wales

“Personal motor vehicle transport is an extremely difficult issue. While fully solar powered cars can zip across the continent at high speeds, they are fragile, lightweight vehicles with more in common with bicycles than Hummers and yet need to share roads with conventional vehicles.

The collection area of a conventional vehicle roof is too small to reliably gather the solar energy to move it about reliably in the ways we have come to expect, although off-vehicle solar collection coupled with on-vehicle battery storage has been shown (Podewils, 2007) to be much more efficient than production and use of biofuels.

Probably, no technical fix could possibly allow us to continue in our current ways indefinitely and we need to walk and cycle more and build up our public transport networks instead of continuing to encourage private cars.”