Yesterday I was listening to a radio programme, Material World, BBC Radio 4, 16:30 27 May 2010
The first part of the prog was about the Iceland volcano eruption, and there was a mention of an unexpected electrical phenomena, I was too busy to pay close attention, so I used the "listen again" facility later and recorded it.
It is still available here, http://www.bbc.co.uk/programmes/b00sgbgs
from that page
I transcribed that part of the prog, it was only a few minutes long, the most relevant part in bold.Quentin Cooper talks to Dr Joseph Ulanowski from the Centre for Atmospheric & Instrumentation Research at the University of Hertfordshire who's co-author of a paper investigating the odd electrical charges found within the plume.
I expect there is less surprise of that finding here, any comments?QC: With me is Dr Joseph Ulanowski from the Centre for Atmospheric & Instrumentation Research at the University of Hertfordshire who we had on the program a month ago to talk about sending balloon borne probes into the ashcloud, he's co-author on a paper investigating the odd electrical charges within the plume...
...Joseph Ulanowski, you were actually launching some extra flights because you were launching some balloon probes into these ash clouds, what were you hoping to find out, what did you find out?
JU: Well, as [Dr] Carina [Fearnley] said, one issue is establishing what the safe limits might be, but the other one is how to predict where the ash is going to end up, and for that there are dispersion models run by the UK met office and by other meteorological services around the world, but the trouble is, normally such models would be verified by using research aircraft which might fly into the ash layers to measure the concentrations but the trouble is that can't be done when aviation is essentially banned from the skies.
Q: Yes, you're in a catch 22 situation...
JU: Precisely
Q: So what did you discover from using your balloon probes?
JU: Well we launched a balloon when the event started in the first week on the request from the met office, who essentially predicted that the ash would be present over Scotland, we launched a baloon with an instrument which actually we developed last for looking at desert dust in the atmosphere, and it just turned out to be perfect for his new application, and as expected the balloon basically found an ash layer about 4km in the atmosphere, quite a thick and dense ash layer, which roughly coincided with met office predictions, but the trouble was we only had two or three of those left, and in order to verfy models we would need dozens, so we are now basically busily trying to build more, so that they could be launched if required.
Q: But you did also look at the electrical properties of these ash clouds...
JU: Yes, that was again something which we did when we were looking at desert dust in Kuwait and off the west coast of Africa, we were looking at the electrical properties of dust, because we were expecting that desert dust might actually be electricly charged in the atmosphere, and that can have consequences for the properties of the dust layers.
Q: In terms of its hazardousness to air traffic?
JU: At that point it didn't even occur to us, although there are some reports of influences of charged dust on for example radio communications, but we did find charging, electrical charging in the mineral dust, but because we had the package ready we basically launched it into the volcanic ash and we found essentially something very similar, the ash is actually charged and in this case was charged after.... over a days movement through the atmosphere so quite a long way away from the volcano.
Q: So is that something of a surprise then?
JU: Well yes and no, one surprise, yes, is that volcanos actually often show electrical activity, there are some absolutely fantastic pictures of lightning around volcanic eruptions, but the surprise element comes because this charging should have dissipated in the atmosphere within hours after the eruption, yet we saw this charging over Scotland.
QC: Karina, clearly, from what Joseph is saying we're still learning about what goes on within these clouds...
How would this be explained from an EU perspective?
I'm tempted to contact the BBC prog team on this with an explanation, but I'm no expert (I'm a technician, retired) so would need your help first, but does anyone here want to contact them?
A few minutes on Radio 4, a reasonably intelligent audience....
CD
