23 comments on “Skaftárhlaup – Glacial outburst flood from under Vatnajökull in progress + Updates

  1. Outburst floods are accompanied by poisonous gasses rich in sulphuric acid

    Far be it from me to query a more or less official report, but sulphuric acid? As a gas? Hydrogen sulphide, yes, sulphur dioxide, yes; but I beg leave to doubt H2SO4 as a gas. For starters, sulphuric acid is so hydrophilic that it would essentially all have dissolved into the water tout le suite. What do the experts on here think?


    • Hi Michael, by no means am I an expert, but sure you are right, and we might have a mishap of translation issue here. However, if I remember right from my chemistry training, sulphuric acid can be formed when sulphuric gases react with air humidity (water), and subsequently be carried in very diluted form via air. Then we have steam/vapour containing H2SO4, and/or acid rain. This has been the very obvious case when, in May/June 2011 (Grimsvötn) in all the northern half of Ireland (and to a lesser extent further south up to Germany) leaves of trees got burnt dark brown, worse than ever seen in autumn.

      In the post I had cited the first issue of that warning, which was specified later yesterday to “[gases] such as hydrogen sulfide and sulfur dioxide”. I’m going to change it now, thanks for the tip!
      Question: is the “f” in sulfur becoming common use in English? I would be far happier with that than with “sulphur” 🙂


      • Hi Granyia; yes, you’re probably right about it being a translation mix-up. I know there ARE cases where an aerosol of sulfuric acid has caused serious burns, but these have tended to be where an eruption has suddenly expelled a strongly acidic crater lake (Taal in 1911 maybe one such). But in this case the acid gases will be in intimate contact (oo-er missus!) with a LOT of water for a fair length of time. You will still get H2S and possibly SO2, but the acid itself will show up only as a decrease in pH of the outflow.. On your other point: I was brought up to use ‘sulphur’ but on reflection I think now that its maybe better to use the American spelling, for a consistent usage on this blog.


        • “but the acid itself will show up only as a decrease in pH of the outflow”… and what is a decrease in ph? A high content of (e.g. sulfuric) acid which is formed easily and fast in water, if pure S or SO2 is present (I don’t know about H2S, it is always SO2 mentioned in this context).
          Wikipedia has to say on acid rain:
          “The principal natural phenomena that contribute acid-producing gases to the atmosphere are emissions from volcanoes. Thus, for example, fumaroles from the Laguna Caliente crater of Poás Volcano create extremely high amounts of acid rain and fog, with acidity as high as a pH of 2, clearing an area of any vegetation and frequently causing irritation to the eyes and lungs of inhabitants in nearby settlements.” and “When clouds are present, the loss rate of SO2 is faster than can be explained by gas phase chemistry alone. This is due to reactions in the liquid water droplets. […] There are a large number of aqueous reactions that oxidize sulfur from S(IV) to S(VI), leading to the formation of sulfuric acid. The most important oxidation reactions are with ozone, hydrogen peroxide and oxygen (reactions with oxygen are catalyzed by iron and manganese in the cloud droplets)”
          In our Skafta case, the (more or less) acidic lake had existed 5 years under the ice, probably influenced by volcanic gases supplying S all the time. Thinking about it, I do believe that the water vapours carry (and with the present SO2 still produce as they flow out) sulfuric acid indeed.

          I am looking at my photos of the plant damage again, and I still find it amazing that up to this day apparently nobody thought it worth mentioning the fact that a volcanic eruption in Iceland damaged the greenery (trees, garden plants, herbs et al) of an entire region involving at least three countries (where I have witnessed it myself) for the whole season. Well, many of the plants grew new leaves all over, but not so the trees in that year. The locals told me: oh that… that’s only wind-burn, happens very rarely, last time 20 years ago, when all the daffodils were burned by a cold storm… Of course I couldn’t tell them, look up the GVP, it was Hekla’s work in 1991! It is a s clear as vitriolic oil to me that it was the acid in the air moisture that had been blown south by that violent storm on 28th or 29th of May 2011 (which originated from a very low low over Iceland). Or, the Sulfur itself could have been carried over with the ash that came aplenty, and, clinging to all surfaces, sulfuric acid had been formed with the moisture on the spot.

          Some may remember that I have posted comments on the burned plants in several other blogs and forums since 2011, but as there has never been an answer I am still waiting for someone who can confirm or dismiss my reasoning. — Oh, it got a bit long, sorry… :/


    • I’d not want to be a hydrologist in that hut! I mean, there’s getting close to your work, but that would be maybe beyond the call of duty 🙂


      • Oh, you’d need the hut only in boring dry weather, these days the water to be analysed is visiting you at home, coming to your doorstep by itself… Am I allowed to lol or is the matter too serious now?


  2. Is anyone from Iceland here (hello Islander??) and could help us? I have noticed that the daily “comments by an expert” on the IMO website differ considerably comparing the English versus Icelandic version.
    Today’s Icelandic is:
    “Vatn lekur að jafnaði úr Skaftá út á Skaftáreldahraun. Hraunið virkar sem sía á jökulgorminn í vatninu. Vatnið kemur fram sem hreint lindavatn undan hraunjaðrinum. Eftir 230 ára síuhlutverk er hraunið orðið fyllt að stórum hluta og yfirborðið farið að þéttast. Allar líkur eru á að næstu daga muni jökulvatn ná fram af brún hraunsins út á Landbrotshraunið sem er undir Eldhrauninu og renna eftir farvegum lindalækjanna. Jökulvatnið mun fyrst koma fram í Tungulæk. Skrifað af vakthafandi sérfræðingi 03. okt. 13:51”

    Could we get a translation, pretty please?

    Today’s English version is different from yesterday’s as well as different from the Icelandic, telling us mostly what everybody knew already:
    The Skaftá outburst flood peaked downstream at midday on 2 October. On the Eldvatn river, discharge peaked at ~2,200 m3/s, excluding floodwater that overtopped a levee upstream from the bridge over Eldvatn. Note that floodwater will continue to drain in the coming days through the Eldhraun lava-field, resulting in water accumulating against Highway 1 between Eldvatn and the western outskirts of Kirkjubæjarklaustur. For travel information, see: http://www.safetravel.is and http://www.road.is. Written by a specialist at 03 Oct 13:51 GMT”

    http://www.vedur.is/#syn=vatnafar (I)
    http://en.vedur.is/#tab=vatnafar (E)


  3. Updates added to the post, probably the last one if nothing exciting happens during the coming days.


  4. Almost six weeks into the eruption, Piton de la Fournaise is still going strong and steady:

    Just for the record:
    An earthquake swarm on the Conchagua Peninsula (SE El Salvador), covering the area of inactive Conchagua volcano, has produced 1081 shallow EQs up to M 4.5 since Sept. 29. 2015. In their report. MARN state that the seismicity is caused by the activation of local faults. A similar swarm in 1991 had over 7000 EQs, another in 2011 almost 2000. http://www.marn.gob.sv/index.php?option=com_content&view=article&id=3475%avisos-ciudadano&catid=25%3Athe-cms&Itemid=76

    showed an episode of continuous tremor again for several hours this afternoon:

    A while ago a photographer had been publicly accused of publishing manipulated pictures showing incandescence in Cotopaxi – wrongly, as it seems now! I feel sorry for the man, because surely his reputation got stained by this. Yesterday (3 Oct.) the IGEPN’s own webcams registered a quite impressive glow from the crater.

    Now Cotopaxi does what everybody expected but nobody wanted to happen – it entered a new phase of activity, whith magma rising quietly inside. Temperature measurements and visual surveillance show that the glacier on its upper part is melting rapidly, cracks appear in the ice and blocks of ice are falling down the steeps slopes. This melting has already caused small lahars in recent weeks as the melt water trickles down and remobilizes ash laid down earlier by the phreatic eruptions. This was detected during an official overflight on 27 Sept. (Src.: ElComercio.com, 03/10/2015)


  5. Veniaminof (Alaska) has been set on Yellow (Advisory) alert
    “Beginning Wednesday, September 30, seismic activity in the form of small low-frequency earthquakes began to be detected at Veniaminof. On Thursday, AVO raised the Color Code/Alert Level to Yellow/Advisory. The character of the seismicity is similar to that seen previously at the volcano, most recently in the waning stages of the 2013 effusive eruption. Most satellite and webcam views from the past few days have been obscured by clouds. Clear views yesterday morning from the FAA Perryvile NW webcam showed no eruptive activity at the volcano.” Src.: AVO Weekly http://www.avo.alaska.edu/activity/Veniaminof.php
    All further daily reports say tremor is continuing but there is no no evidence of an eruption.

    Interesting looking volcano!

    August 18, 2013: A small puff of ash emerges from the active cone inside Veniaminof caldera. A beautiful fan of lava flows active earlier in the summer descends the south flank of the cone onto glacial ice producing white steam clouds and depressions where melting has occurred. The surrounding glacier is darkened by recent ash fall. (Image: AVO/McGimsey)


  6. Wow, here is something interesting!:
    “The first simulation of the individual crystals in volcanic mush, a mix of liquid magma and solid crystals, shows mixing to help understand pressure buildup deep inside a volcano.” Even I can understand that video… 😉 Ref: G. W. Bergantz, J. M. Schleicher & A. Burgisser. Open-system dynamics and mixing in magma mushes. DOI:10.1038/ngeo2534 Read more : http://www.geologypage.com/2015/10/simulating-path-of-magma-mush-inside.html


    • The simulation demonstrates why only a relatively small part of the eruptible magma in a crystal mush actually erupts. Wonder how close it is to reality. Cheers –


  7. ALAID, northern Kurile Islands: Aviation Color Code set to YELLOW. KVERT reported that an intense thermal anomaly was detected in satellite images over Alaid starting at 03h05 on 2 Oct., possibly due to Strombolian activity. Up to date moderate eruptive activity of the volcano probably continues. Satellite data still showed a thermal anomaly over the volcano. Three images below are from
    1. Landsat 8 OLI, 05/10/2015 – 2. TERRA/MODIS 07/10/2015 – 3. MODVOLC 05-07/10/2015 (three days combined)

    Alaid is a stratovolcano “Somma-Vesuvius”-type, on the Island of Atlasova, ca 70 km SW of Kamchatka. Inside the summit crater is a young cinder cone of 250 m hight. On the slopes of the volcano 33 side cinder cones have been produced by earlier eruptions. It breeds basalt (sorry, Google joke, couldn’t refrain! should read: erupts basaltic lavas), and its ashy eruptions can affect the neighboring inhabited islands and most often international aviation routes crossing the area.

    Fumarolic activity of volcano Alaid Oct. 27, 2012, by N.V. Ushakov, via KVERT


  8. Pingback: De puerto en puerto : Un día en Fjallabaksleið Nyrðri

Your thoughts?

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s