In a Warmer World, Iceland's Volcanoes May Get Even Livelier

By Aline Reynolds | April 19, 2010 12:49 pm

Eyjafjallajökull_glacier_inThe volcanic eruption in Iceland that has disrupted air traffic in Europe is also a reminder that other volcanoes in the region could wake up if global warming continues unabated, experts say.

Scientists say that if large icecaps on the island melt, they’ll ease the pressure on the rocks beneath the surface. Lifting the weight off the rocks would allow for more magma production, which could set off other eruptions. Says volcanologist Freysteinn Sigmundsson: “Our work suggests that eventually there will be either somewhat larger eruptions or more frequent eruptions in Iceland in coming decades” [Scientific American].

Scientists clarified that while the current Eyjafjallajokull eruption occurred beneath a small glacier in Iceland, the explosion was not caused by global warming. The Eyjafjallajokull glacier is too small and light to have an impact on local geology, they say.

Sigmundsson and his colleague Carolina Pagli published research in 2008 estimating that the melting of about a tenth of Iceland’s biggest icecap, Vatnajokull, over the last century had caused the land to rise about an inch a year and led to the growth of a vast mass of magma, measuring about a third of a cubic mile, underground [The Telegraph]. The researchers explain that heated rocks can’t melt into magma when they’re under high pressure–for example, when they’re squashed underneath the weight of an icecap. But when the ice melts, the water trickles away, and the pressure eases off, the rocks can then melt into magma, creating prime conditions for volcanic eruptions. The researchers note that the end of the Ice Age 10,000 years ago was marked by an increase in volcanic activity in Iceland.

They warn that if ice sheets shrink, we can expect to see more eruptions in other frozen places like Alaska, Patagonia, and Antarctica. Says Pagli: “The effects would be biggest with ice-capped volcanoes…. If you remove a load that is big enough you will also have an effect at depths on magma production” [Scientific American].

Related Content:
Visual Science: Up Close and Personal With Iceland’s Volcanic Eruption
80beats:Icelandic Volcanoes–Disrupting Weather & History Since 1783
80beats: Volcanic Eruption in Iceland Causes Floods, Shuts Down European Air Travel
Bad Astronomy: Iceland Volcano Eruption Making an Ash of Itself
DISCOVER: Disaster! The Most Destructive Volcanic Eruptions in History (photo gallery)

Image: Wikimedia/Chris 73

  • Bill Jenkins

    Junk science.

  • carddan

    Not so much “junk” as just pure propaganda. If the premise is true, isn’t it a good thing? The eruptions will happen eventually. If a lighter glacial weight allows them to happen earlier doesn’t that mean they will be less explossive and cataclysmic when they do occur? Livelier and more active would indicate less destruction. The authors only see one perspective: it is caused by the activity of man and therefore is “bad”. A real scientist would not be influenced by that perspective. This is not “science”, it is propaganda. Think for yourselves.

  • nicole

    Hey, shut up. Its actually called geo and it was my favorite subject when I was a kid. So dont diss it!!!!!!!!!! (Now science sucks, Geo does not)

  • thinking for myself

    People who say ‘think for your self’ are always trying to force their opinion down other people’s throats, just like the ones who say ‘common sense’. Why don’t we start keeping track of all the people who are fighting against thinking and reason and hold them accountable for the destruction that results from their dangerous actions?

  • carddan

    I didn’t say the hypothesis lacked merit. I stated my belief that if correct, it would benefit mankind. I do question the motive behind the preposition. So, when I say “think for yourselves”, I am not saying my opinion is correct. I am saying consider the motives behind the theories and opinions, even mine.
    Would it hurt to discuss my hypothesis that having more frequent volcanic activity might be less harmfull than storing the energy for a cataclysmic event?

  • nicole

    you guys do not speack normal english. even my friend’s daughters, who are in 6th grade, would not understand those words.

  • jackmo

    To Jenkins: Please explain why it is “junk science.” Just because you apparently are ignorant of geology is no basis for dismissing the article.

    The question for carddan is whether frequent eruptions spewing ash like the present would “benefit” mankind. Maybe fewer eruptions would be better for mankind, or certainly for air traffic. I suggest further that the report does not express an opinion or even a theory. That melting of rock increases with reduction of overburden is simply a fact of nature that has become well know to geology. There need be no motive behind it — simply a statement of fact. Your unsupported opinion on the other hand may well have an underlying motive to see the world the way you wish it to be rather than the way it actually is.

  • carddan

    My opinion that more numerous/weaker eruptions is less harmful than fewer, but larger cataclysmic events, is unsupported. It is just an idea that seems logical to me.

    From the original article in Scientific American: attributed to Freysteinn Sigmundsson, is the following quote: “He said that melting ice seemed the main way in which climate change, blamed mainly on use of fossil fuels, could have knock-on effects on geology. The U.N. climate panel says that global warming will cause more floods, droughts and rising seas.”
    This quote puts into perspective the opinion of the entire article and implies that the science of “climate change” is settled.

    The scientific premise of the article may be correct, but the motive behind it is suspect. It assumes that global warming is caused by man, that may or may not be true. I will at least admit my beliefs are unproven opinions. Can you say the same?

  • jackmo

    Yes, I can. I have offered no opinion on causes of climate change, But whether human-caused or not, the observation of melting ice is verified and the effect on rock melting is simply a fact of physical chemistry. This is not conjecture and certainly not my opinion. While not a vulcanologist, I am a geologist with sufficient training to recognize that magma production is a function of the chemical composition of the rock, the temperature, and the pressure. Change of any of those will cause a change in the phase of the rock, e.g. solid to liquid. Even if mentioned in the SciAm article, the issue of fossil fuel use as a cause of global warming has no direct bearing on the phenomenon itself. Volcanic activity will increase with increased magma production along this continuation of the mid-Atlantic rift. If humans are accelerating the process, that is only ironic.

  • Brian Too

    I’m kind of questioning the premise behind this article.

    #1. I thought that compression was a major force behind magma production. Compression automatically heats rocks, so more compression = more magma. The article seems to be saying less compression = more magma and linking that to water in the rocks?

    #2. Iceland’s status as a major location of volcanism is directly linked to it’s position on the Mid-Atlantic ridge. This status is tied to the mechanism of plate spreading, which is driven by processes in the mantle. Aren’t the plate spreading forces huge, vastly greater than any glacier in Iceland? Isn’t this like trying to weigh the dog both with and without fleas?

  • jackmo

    Actually, you are wrong about compression and magma production. As I mentioned previously, even when heated intensely, rock does not melt when under high pressure. It does melt when pressure is released. You are correct that the Icelandic volcanoes are located on a spreading tectonic boundary. Volcanic activity is associated with such boundaries and we are experiencing such at present in Iceland. The effect of melting ice might be dismissed, were it not for the observation that magma chambers have grown beneath regions overlain by ice caps both in the present together with the observation that volcanic activity increased following the last ice age. Rebound (glacio-isostacy) of the crust is a response to relief of pressure with melting ice. This is measurable and known to be accompanied by seismic and other phenomena. I am not an expert in either vulcanology or global tectonics and would be interested in other assessments by experts in both these fields as to the relative contributions. The original work, however, was published in the Geophysical Research Letters, and subject to peer review by other experts.

  • carddan

    Jackmo, I find nothing to disagree with in your last post. If it is true that a lesser volume of ice (whatever the cause) will allow more or more frequent eruptions, is it plausible that those eruptions would be less violent than if they were surpressed by heavier ice?

    I will confess that I believe Scientific American and Discover have exhibited a consistent support of the theory of man caused global warming. That theory may be correct, but both of these publications describe it as fact. If the Big Bang or the Theory of Relativity is debatable, so is climate change. When it is not discussed with an open mind, I become sceptical of motives.

  • jackmo

    Card, I am not a vulcanologist and cannot really comment on the “severity ” of eruptions or what that actually means. I can say that generally, eruptions along spreading zones tend to be relatively “quiet” compared to those in continental crust like Mt St. Helens– note that Iceland is actually compositionally closer to the ocean floor material and when molten flows easier. The problem I think has more to do with frequency and duration rather than explosiveness in the case of Iceland. That a relatively small volcano has had such a devastating effect on air travel is disturbing. One would hate to think of these eruptions occurring more frequently or lasting years, for example.

  • jackmo

    Card, lol – the Big Bang and certainly relativity are not really debatable. Relativity has been tested and proven to a high degree of certainty. Most scientists recognize the Big Bang as the best accounting for astronomical observations. That most answers in science generate many more questions is not really debate — rather the process of science. Every idea proposed must be tested and even then cannot be known without some level of uncertainty. In evaluating any scientific proposition, even that of global warming and possible human contribution, one must consider the degree to which the idea is consistent with the body of research. Currently the notion of global warming is occurring, and human contribution is very likely. In order to consider alternative explanations, evidence must be supplied in the form of research by appropriately trained and experienced scientists, published, and subjected to peer review. There is plenty of that in support of global warming and effects of humans — I have seen nothing convincing to the contrary. Often such “evidence” is not supported by actual research and those supplying it are not qualified in the relevant fields. I am not expert in any of these fields, but know how to evaluate the credibility of those who claim to be.

  • carddan

    Jack, thanks for a rational discussion. The Anthropogenic Global Warming Theory has no where near the status of the other “theories” I mentioned. AGW is a new concept which correlates with what certainly appears to be a relative warming trend in the late 20th century. Not having alternative explanations does not prove the hypothesis however. I also have seen no convincing theories on why the earth has been alternatively ice covered and ice free over the last 4.5 billion years. Scientific research grants at major universities are available to those whose research is “chosen”. I have a hunch you are familiar with this. I know first hand that these grants are given to scientists supporting AGW and environmental concerns, not against. My experience is in Agriculture. You can get a million dollar grant to study the effect of different cattle feeds on methane production, you can not get a grant to study which feed produces the most beef. I am not saying this is right or wrong, just that it has an effect on the research being done. Who has a million dollar grant to study whether the fluctuating solar cycles have an affect on climate?

  • jackmo

    Card – I see your point to some degree and definitely that regarding the availability of grants to study cow farts – lol. I think quite a bit of research has been done and ideas advanced regarding causes of glaciation, and much of the climate research, particularly with regard to paleoclimate, I believe to be agnostic with regard to AGW, e.g. ice core studies in Antarctica and ocean core studies. Fluctuating solar cycles, a la Milankovich, are probably involved to some extent. I don’t think most climatologists ignore these effects. Any human effect would be overlain upon these and may accelerate natural processes.

    While there are certainly exceptions in the awarding of research grants, I do not think that research is typically funded to support one position or the other — rather it may be funded to test certain hypotheses regarding causes, to improve models, etc. To buy conclusions would be anti-scientific. My experience in a government lab is that research is conducted objectively and is always qualified by quantitative assessment of uncertainty.

    Your notions regarding motives are significant to some degree, however, and worth considering. I also consider them and use the “follow-the-money” rule. In considering the source of the research, and not necessarily those that point to it, I ask what would this source have to gain by twisting or compromising the results. I see little reason for most academic researchers or government scientists to lie about their results. On the other hand, I see many reasons for oil companies to buy conclusions contrary to AGW.

    The problem is that if we do nothing, we may not have a chance to escape our fate. If we act to reduce use of fossil fuels, we at least gain alternatives to this dwindling resource. At most we avert major socio-economic catastrophe.

  • carddan

    Jack, if more people were capable of separating the politics from the science, we would be better served. You obviously understand, well done.

  • Nomad

    Wow, there ARE intelligent conversations on the internet…here’s my two cents.

    Professor Alastair Dawson’s book, “So Foul and Fair a Day,” includes insights into Icelandic volcanoes: “After another cold winter in 1689 to 1690 we enter the 1690s, associated by many with the lowest air temperatures throughout the period 1350-1700. Across northern Europe it was once again a time of dislocated society, population decline and abandonment of farmland. Scotland’s climate was already in shock from freezing winter temperatures and wet summers when a series of volcanic eruptions took place. Mt Hekla, in Iceland erupted in 1693, depositing ash across much of Iceland and as far afield as Scotland and Norway. It is also well known that a major southward extension of sea ice took place at this time across the Northern North Atlantic. Whenever this happened, the tracks of storms were displaced further south than normal, leading to bitter winter winds and exceptionally high rainfall across Scotland.”

    Hey look we have the lowest air temperatures in 350 years…


    …Boom goes the dynamite! The eruption of Mount Hekla.

    the Reuters report states: “The end of the Ice Age 10,000 years ago coincided with a surge in volcanic activity in Iceland, apparently because huge ice caps thinned and the land rose.”

    Have there been major fluctuations in global temperature for as long as can be measured?

    Has there been any influence by the solar cycle on global temperatures?

    How much of what we’ve heard about Global Warming is political?

    Is it possible that an increase in volcanic activity expedited the glacial melting in the 1600’s?

    I think the answer is that we don’t know, it’s staggering to see what we know about the planet juxtaposed with what we like to think we know.

    I am not saying man has had no effect on the environment but I think too much credence is given to man’s impact on the environment (based largely on a fancy slide show) while ignoring many other factors. The planet goes through cycles and there is nothing we can do about it, it is a self correcting system, it will get colder again with no action by us, there will be other ice ages that will not be our fault. There will be other periods of warming that will have nothing to do with us.

    …and Jackmo, I agree that we need to find alternatives to fossil fuel because we are running out and to avoid a socio-economic crisis, not because of the environment (ask Al Gore what his private plane runs on, bio-fuel?…um, no) Flying in a private plane does four times the “carbon damage” to the environment than flying in a commercial jet, if he was really that worried about a “carbon footprint” he would hug a tree and sit in coach, but I digress.

  • TW Moth

    This has been an interesting discussion. Thank you Carddan and Jackmo. The question I have is, doesn’t the increased frequency of volcanic activity actually help to slow the global warming process? Don’t the catastrophic volcanic eruptions, or the really long lasting volcanic eruptions create ash clouds which actually cool the earth/climate. Is this icecap melting leading to more volcanic eruptions, leading to more cooling kind of a self-regulating feedback loop. Maybe my thought is way off base, because my field is psychology so I am way out of my league talking about geology, vulcanology and climatology.

  • Nomad

    TW, my field is also Psychology, but I have a heavy interest in the physical sciences. I actually had that same thought earlier today. As I stated before our climate is a self correcting system, and I think that it could very well be that, it will lead to cooling. There is a theory that volcanic activity led to the little ice age that lasted from about 1250 to the 1800’s.

  • TW Moth

    Nomad, my concern is that there have been catastrophic events that the self-correcting climate system has not been able to recover from–at least not in a way that allowed for the survival of many major life forms (i.e. the massive climate change that led to the end of the dinosaurs). Of course, if the current trend in climate change is anthropogenic, then the self-correcting system may not be able to self-correct (at least in the short-term) because human activity is outside the bounds of this self-correcting system. In the long-term–the climate system may self-correct by killing off all human life forms and therefore eliminating the anthropogenic source of climate change–unfortunately it may also eliminate a substanital amount of carbon-based life forms at the same time–thus changing the climate system into something entirely different from what we have known for 100’s of millions of years

  • Harry Braun

    How does burning a river of oil compare to these volcanic eruptions?

    According to David O’Reilly the CEO of CHEVRON, the world currently consumes oil at a rate of about 40,000 US gallons per second. He says, “the scale of the energy system is enormous.”

    Imagine a river of oil.

    I thought it might interesting to see just how much oil we are talking about here, so I compared the amount of oil that we are currently burning in the world to the amount of water that flows in various waterfalls.

    I used average yearly flow rate figures.

    The flow rate of Jog Falls is about 153 cubic meters per second, a little less than our imaginary river of oil.

    You can see what 153 cubic meters per second looks like here:

    Read: According to the CEO of Chevron

  • http://Soy74**salva j.s.

    Look, I don’t know, but am scare.

  • Nomad

    There had to have been many convening factors that wiped out the dinosaurs. Meteor, volcanic activity, dwindling food supply, disease and climate change. I don’t think that one of these were the culprit, I think that it was a number of causes.

    The earth has also been completely frozen or nearly frozen at least once during the period ranging from about 650 to 750 million years ago.

    95% of all species that have ever lived on the Earth are extinct. There is something that separates us from them though, we have the ability to reason, build shelters, evade, as well as the fact that we may be able to see the apocalypse coming and run. Will people die? yes. Will the human race die out? Maybe, but perhaps we can take a page from our tiny mammalian ancestors and hide underground. Would this be ideal? No, but it would not happen overnight and probably not within our or our children’s lives.

    Even if it does happen, or if something that we have never seen occurs, we can be assured that life will find a way.

  • carddan

    This article discusses cause and effect. Many scientific discoveries are made by observing coincidences and then hypothesizing connections. Does volcanic activity drive changes to the climate or do changes in climate effect volcanic activity? Perhaps both are possible. My hunch is that both are effects of a much more complicated system, or cause, which we have virtually no understanding of. It has been observed that massive volcanic eruptions cause a short-term decrease in global temperatures. It is also theorized that the Earth was once completely ice-bound and that it was volcanic activity which provided enough green-house gasses to break the grip of ice.
    When considering apparent “coincidences”, I also note that the Solar Cycles 22 and 23 were very active and that Cycle 24 has been slow to develop and is likely to be weak and short. This is not what NASA predicted and indicates that the variation in Solar Cycles is driven by a mechanism which is not well understood. (I believe that observing sun spots is observing an effect of solar magnetic activity, not a cause) Is it possible that solar magnetic activity has an influence on climate and or volcanoes? Can anyone explain why the Earth’s polarity occasionally reverses and what implications those events have? Connecting some of these ideas seems farfetched, but considering how little we understand about predicting solar behavior, volcanoes and earthquakes, and in my mind, the climate, aren’t they questions worth asking?
    Thank you everyone for a good conversation. Some things I “know” and some I don’t. The only things I’m ever wrong about are the ones I “know”.

  • Mike Licht

    The cause is plain. The Norse gods are enraged about Iceland’s bank collapse.


  • carddan

    Nomad, I think you’re scaring the kids, lol. These icelandic volcanoes are not the extinction causing type. They are nothing compared to the “super volvanoes”. The DNA evidence that Toba’s eruption some 70,000 years ago may have reduced the human population from a couple million to 10,000 is compelling. Of course, it was an icelandic volcano which is blamed for helping create the famine which led to the French Revolution and the extinction of the French Nobility.

  • Nomad

    Thank you for clarifying, I wasn’t saying that any one of the Icelandic volcanoes are like the Toba eruption, or the more terrifying Yellowstone caldera, which if it explodes, immediately impacts the worlds food supply, as most of it is grown in the middle of the U.S. if that happens revolution will look like a church picnic compared to what will happen. There will be another genetic “bottleneck”, but the human race will survive.

    Here’s something to lull the kids to sleep, the Yellowstone caldera blows every 600,000 – 800,000 years…the last eruption was 640,000 years ago. The earth above the caldera has been rising as of late and would dwarf the Toba eruption. If that eruption reduced our numbers to 5,000 – 10,000, just imagine what Yellowstone can do.

    Sweet dreams…lol

  • carddan

    Nomad, I wasn’t trying to correct you before, just having fun. If Yellowstone goes, there might not be anyone to hypothesize on how CO2 emissions caused it.

  • Nomad

    lol…I know, I was seriously thanking you for the clarification, and I am having a lot of fun with this :-)

  • Warren Emerson

    The sentence “Scientists worry about [fill in the blank] is becoming boring. They are developing a reputation of ‘The boy who cried wolf.’ In this case, if the event actually occurs, the possible effect of more volcanoes could result in lowered temperatures, and we would then be glad that there is a global warming effect to offset it. The climate bounced to extremes 15,000 to 12,000 years ago suggesting massive quick changes. The point of this is that trying to predict precisely what will happen in the future climate is a fools errand.

    From a policy point of view this suggests that instead of trying to prevent the inevitable, we should be learning and planning on how to respond and adapt. In the last period this occurred, people survived through it, so they were smart enough to respond… mostly by moving from one place to another. In a settled world like today, we should be planning on how we would handle extremely hot weather or extremely cold. In an extremely cold weather situation, it is not inconceivable that Canadians and Americans would want to move to the south quickly. That would make US citizens the ‘wet backs’ trying to seek asylum in Mexico…

  • m

    omg…are you kidding me?

    There’s so much wrong with this article, I need a Scotch just to get organized.

    This is why I limit my “Discover” exposure to online and have cancelled my subscription.

    Shame on you Discover – you used to be better than this. It just breaks my heart.

  • RockyRoad

    As one who has a BS and MS in geology (and my master’s thesis was on vulcanology), I can tell you attributing this or any other eruption to the implausible theory of global warming is laughable. Sure, removing some ice from above a volcano may make it erupt a bit quicker, but the driving forces behind volcanoes has precious little to do with global warming. (Yet the reverse is true–volcanoes have had a very significant impact on climate and will continue to do so; they are probably the biggest contributor to mid-term temperature swings since their activity seems to by cyclical and clustered, outstripped only by large meteor impacts.)

    “Global Warming” has so imbued the thought processes of so many scientists that they look at all phenomena through CO2-colored lenses yet past temperature extremes had nothing to do with CO2–the abundance of that gas in the atmosphere is a trailing indicator, and not a causitive, leading indicator. (The biggest immediate source of CO2 is volcanic eruptions, yet the dust factor has cause a significant DROP in global temperature, not a warming.)

    There have been hundreds of temperature swings in the past million years and while there are a number of factors driving these swings, a primary cause is volcanic activity. And no, anthropogenic factors were not the cause. Man’s puny impact is way overblown; many scientists can’t even see it in the measurements.

    Sorry, but I’m not going to provide references for my position–you all are capable individuals and can dig out sufficient resources to suit your own purposes. My opinions are based on decades of studying the science and evaluating what hundreds of researchers have had to say on the subject. Some are laughable in their conclusions (I think they’re chasing grants which is despicable behavior because it distorts the outcome) while others are impervious to the current political winds and are objective in their conclusions, which is what real science is all about.

    There’s way too much post-normal “science” out there, which is horribly sad since that isn’t science at all. Post-normal science is akin to ascribing CO2 as the cause of volcanic eruptions–it may be politically correct to do so and models may be built to show a correlation (what can’t be modeled, right?), but it isn’t based on observation. Oops!

  • carddan

    RockyRoad, if you add a PhD (piled higher and deeper) to your BS and MS (more of the same), perhaps you can get multi-million dollar grants to manipulate statistics and support post-modern science. Until then, thanks for the refreshingly intelligent, common sense perspective.

  • John

    Just wait til Yellowstone or Mammoth Mountain erupt!

    Ice Age, Baby!!

  • Nomad

    If Yellowstone goes, it may very well mean the end of the human race.

  • Diann

    If the Earth cools will there be less volcanoes? Just curious because they say the Earth is cooling.


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