The latest swarm in Iceland has many people unsettled. Fears are rife that there will be a repeat of the Eyjafjallajökull episode, when European airspace was closed down for weeks at a time and people were left stranded. Others are afraid they might actually be impacted by an eruption itself and have fears for their safety.
This blog has never pretended to be any kind of authority in advising people and for some very good reasons:
- None of us are professionals in the field, or at least those few of us who are, are not acting in a professional capacity here
- The only data we have at our disposal is the same data in the public domain that anyone can access via the internet. We do not have access to the huge wealth of data that the professionals have
- We simply cannot compare to the qualifications that the professionals have. True, many of us are extremely well read, but it is one thing to read the scientific articles and quite another to actually author them. A scientific paper is based on weeks, months and sometimes years of research. It is subject to peer review. The actual paper that is released is just the distilled essence of all that work. Thus, us readers are just the gnats sitting on the shoulder of giants, the scientists who do the groundwork, and, on top of that, we frequently misread what the experts are telling us.
That said, VolcanoCafé is getting lots of queries from people who are unsettled about developments in Iceland. Hopefully, the following will help address those fears.
Listen to the authorities first and foremost.
These people know what they are talking about. They also have an amazingly good track record in the past. You can trust them.
What are the actual risks?
This is probably what people are most interested in, so I will try to break this down into the various risks that might impact people in the unlikely/likely/possible/probable event of an eruption (take your pick of adjective – this changes daily).
- Ash closing airspace
Ever since Eyjafjallajökull closed down European airspace (at huge cost and inconvenience) this risk is foremost in the public eye. So what are the risks of it happening again?
Well, this is hard to quantify because it depends on a lot of variables:
- the quantity of ash
- the fineness of the ash (fine ash stays aloft longer)
(how fine the ash is depends on the type of magma and how much gas is present in it to blow it apart. The gas might be contained in the magma or added by melt water from the icecap
- the wind direction
- the amount of moisture in the air
- the height of the eruption plume
- the duration of the eruption.
- the eruptive rate (how fast ash is getting pumped out)
Although Eyjafjallajökull was a mouse-sized eruption it had an elephant-sized impact because a lot of the above variables came together in a critical combination. The ash was fine, the eruption kept going for weeks, the wind blew the ash towards Europe, and finally, the ash was not washed out because Europe had an unusually long bout of settled dry weather.
However, there are a lot of factors in this current eruption that point towards this NOT happening again this time around.
- First, there might not even be an eruption
- Second, if there is one, it is looking as though it will be a nice and pretty lava fountaining/flow type event that we are familiar with from Hawaii and not an ashy central vent eruption (this could change at short notice)
- Third, even if there is an eruption and it is ashy, there is a lot of moisture in the air, which will tend to wash it out.
- On the other hand, wind patterns are not currently very good for Europe. Moreover, if the eruption occurs under the icesheet, water will tend to make any eruption ashier and the ash generated finer.
- Immediate impact from an eruption
If there is an eruption, and that is a big if, you would have to be pretty unlucky to be immediately impacted by it. The civil defense authorities are on to this and have already closed off inaccessible areas north of the swarm. The greatest risk here is being caught in a flood (jökullhlaup) from melt water from the glacier. These are one of nature’s greatest wonders but they are enormously destructive and extremely unpredictable. Just stay away from the areas banned by the authorities. They know all the watersheds.
A second possibility is ash fall. Here too, this depends on the nature of the eruption. Iceland is capable of dumping a lot of ash not just on Iceland but also NW Europe but this does not happen very frequently and there is no indication at present that this sort of eruption might be involved here, if it even happens. If, contrary to expectations a sudden large eruption does dump ash on you, take care. It is extremely abrasive stuff and very bad for your lungs. Wear a mask, stay indoors and if you have to move outside, remember that ash can clog your car’s filter. A damp cloth over your face will help and I remember someone from Chaiten saying cutting an onion was very helpful to keep the stuff out of your eyes. BUT, this scenario is pretty unlikely. Icelanders themselves are familiar with the stuff, so just ask a local if you happen to be caught out.
Volcanic gases have played a role in the past, notably the Laki eruption, when a lot of fluorine led to livestock poisoning. Again, this type of thing happening again is a remote possibility but possible. Again here the risk is dependent on concentrations and wind flows and these are impossible to predict at present. Of all the risks this is the lowest.
(*Edited at request * Flourine in the ashes poisoned the livestock in Iceland. A cloud of SO2 swept over Europe. Plants and humans suffered from the consequences. Spica.)
Thankfully, due to the remoteness of the location, none of the other volcanic risks play much of a role here (pyroclastic flow, tsunami, etc.)
- Likelihood of these risks eventuating
Due to the number of variables involved calculating the probabilities involved is fraught with uncertainty. But generally, the law of probabilities applies and that is most eruptions are small gentle affairs and the big nasty ones are much less frequent.
It is still highly uncertain at present that there will even be an eruption.
Secondly, if there is one, it is more likely to be a tame affair than a big eruption.
Thirdly, if by chance, it turns out to be a bigger eruption, there are still two options: it might be an effusive lava producing affair that will flood the surrounding landscape with lava or it might be an ashy central vent eruption. If the former, ash is unlikely to be a major issue (except where water is involved) but gases might be. If the latter, ash could be an issue, depending on the coarseness of the ash, the duration of the eruption, the volume and power of the eruption, the wind direction and the moisture in the air, as explained above. By way of comparison, Grimsvötn erupted way more ash than Eyjafjalljökull recently but it had virtually no impact on air travel, at least not long-term, because there was not the same critical combination of the variables needed to impact airspace.
Hope this helps. There is no need at the moment to be unduly worried1. Once again, listen to the authorities. They really do know their business.
1 I hesitate to say this because some authorities in Italy got jailed for saying something similar before an earthquake that killed 350 people in Aquila. Remember, there is ALWAYS risk, in whatever you do, even cleaning your teeth. Iceland is created entirely from volcanoes. It is what makes the place so special. Moreover volcanic activity, like any force of nature, a thunderstorm for instance, is both beautiful and awe-inspiring. If you are prepared and know the risks, you can do a lot towards minimizing those risks and yet still enjoy the spectacle.
I would like to welcome every newcomer to Volcanocafé on behalf of all the Editors (called Dragons) in here.
Volcanocafé is during the weeks a pretty serious place were we discuss all things volcanic. In here you can get most answers to all things volcanic, but on friday evenings we relax and do a few things that most serious popular science places do not do. For instance our tradition with Riddles (volcanic of course) is one of them. The other thing is our “Bar”. We call it the Sheepy Dalek Bar.
The sheep part comes from a night during the Eyjafjallajökull eruption in 2010, when a particularly gnarly storm raged with wind peeks of 250 kilometers per hour. Across the webcam a sheep came flying, since then sheeps have been on our minds. The Dalek comes from the Búrfell webcam (that covers Hekla), it is actually a seismometer station, but it truly looks like a Dalek.
Fridays is when the oldtimers in here goes slightly bonkers, after all it is Friday and we are among friends.
Now a short one on rules and Volcanocafé. We really do believe in freedom of expression in here. And we have a lot of heated discussions, but they are almost to a fault friendly discussions. So, in a sense of it we have only one rule: “Be polite”. There are a couple of more, but they can be found in the links up above. It is amazing how few we actually have.
Well, you are all now duly warned that adult serious people will start to post odd things and music videos. So, welcome to prepare something to drink and enjoy the evening.
On Friday nights we usually relax and entertain ourselves with drinks and music and we have a set of riddles. Everyone who wants can join in and try to solve them. Ding means a correct answer was given. Our riddle master is Matt and either he or a dragon will do the Dinging.
Read up on why this bar is called Sheepy Dalek and why we are fond of Daleks and sheep on the first Birthday post written 2012. http://volcanocafe.wordpress.com/2012/11/14/birthday-post/
We are glad you joined the crowd here and we hope you keep on stopping by.
Expect riddles to be added on Friday evening blog time. *edit*: The riddles have been appended! Good Luck! Have fun!
ps: don´t forget our page with links up in the menu: http://volcanocafe.wordpress.com/info-on-bardarbunga/
For your normal friday entertainment-> The riddles by riddle master Matt
This week the answers to Matt´s riddles there are three volcanoes, one volcanic feature, and one volcanic term. 2 points are awarded for each correct answer, 1 point after a clue was given.
#1 Riddle: Hot rocks + image
Clue It has everything to do with domes, ash, and pyroclastic flows, but nothing to do with cars.
#2 In the country where coffee got one of its names, this was the only one to erupt during the 20th century. 2 points Espadrille Harras of Dhamar in Yemen. With Saana’s harbour Mocha as the name for coffee
#3 2 points inannamoon667 Soufriere Hills The volcano came between Margaritaville and Pyroclasticville.
#4 Agave and communists? It’s pretty cool! Clue: Clue: It took a nuclear reactor to find it. 1 point LDP Gakkel Ridge, surveyed by. Arctic Gakkel Vents Expedition.