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A warming world could trigger earthquakes, landslides and volcanoes

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Iceland eruption 2010Volcanoes, with their vast outpourings of greenhouse gases and sun-screening ash clouds, can affect climate. But what about the other way around?

A special issue of the Philosophical Transactions of the Royal Society A, dated May 28, rounds up research on the ways that climate change can drive volcanic eruptions as well as other geologic hazards such as earthquakes and landslides. Among the litany of problems that studies in the issue link to a warming world: mountain slopes collapsing as snow and ice melt, seismic activity increasing as thinning ice deposits relieve pressure on some parts of the world and apply it elsewhere, and magma production being boosted by pressure changes in subglacial volcanoes such as those in Iceland.

It is that last implication that is timeliest, given the worldwide attention paid to the ash cloud from the Eyjafjallajökull volcano that has crippled air traffic across Europe for the past several days. Reduced ice loads atop volcanoes relieve pressure on magma chambers below and allow for more decompression melting of rock, a group of researchers wrote in one of the special issue’s studies, based on observations and models of Iceland. But lead study author Freysteinn Sigmundsson of the University of Iceland told Reuters last week that the latest eruption did not appear to be driven by climate. "We believe the reduction of ice has not been important in triggering this latest eruption," he said. Any additional magma produced as a result of reduced ice loads may take decades or even centuries to reach the surface, the authors wrote.

Melt-driven pressure changes could also bring on more earthquakes. As deposits of Arctic ice grow thinner, those landmasses experience less pressure, whereas rising sea levels increase pressure on coastal regions worldwide. That tipping of the scales, wrote Bill McGuire of University College London, "may be sufficient to trigger a geospheric response." In past postglacial periods, McGuire noted, melting of ice sheets appears to have set off major seismic activity, as sections of the crust previously burdened by ice rise in a process known as isostatic rebound.

In another report in the special issue, Christian Huggel of the University of Zurich and his colleagues looked to recent slope failures in Alaska, the European Alps and New Zealand, finding that "all the failures were preceded by unusually warm periods." Over the coming decades, they noted, models predict that warm periods in the Swiss Alps will increase in frequency by 1.5 to 4 times, possibly more, which could result in an increase in avalanches there.

All told, McGuire wrote, the evidence "supports a robust link between changing climatic conditions and a broad portfolio of potentially hazardous geological and geomorphological processes." Although some have speculated that such processes are already under way, McGuire cautions that "no increase in the global incidence of either volcanic activity or seismic activity has been identified to date" and that the time scale on which any geologic responses to climate change would take shape is unclear.

Photo credit: Boaworm via Wikimedia Commons





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  1. 1. jtdwyer 11:54 am 04/21/2010

    Thanks for clarifying several issues encountered in recent reports.

    From your report, it seems that the geologically quick melting of massive continental ice sheets following the last ice age produced empirical evidence of several effects that are now being weakly extrapolated to the conditions of global warming.

    Since the Earth;s climate has been very warm for the past 300 years, we are not now initializing vast melting conditions on the massive continental ice sheets of an ice age. It seems rather we’re relying on unverified models to apply post ice age large scale processes to existing conditions – a highly speculative venture.

    Keep in mind that at very large scales, icing is a geologic feature and all affects are not likely scalable. Crustal subduction, for example, does not occur at lake shores.

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  2. 2. doug l 2:29 pm 04/21/2010

    Fancy that, you forgot to mention how all those natural phenomenon have negative feedback mechanisms that would actually cool the planet. It’s almost as if you are trying to generate increased readership by fear mongering instead of scientific understanding over the natural processes of planetary change that all species, including humans, have evolved with over the eons.
    A science writer would have to be a sociopath to want to do that, wouldn’t they?

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  3. 3. Sisko 2:39 pm 04/21/2010

    I wonder if there has bee any modeling done regarding the effects to climate of the shifting of the magnetic poles on the planet. That obviously entails a significant shift in the core of the planet, and it would seem could effect the climate. Aren’t we at/near the time period when this shift should be occuring? Ok, maybe it is a half baked idea

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  4. 4. FrancoisTheriault 4:46 pm 04/21/2010

    I guess nobody wants to hear that volcanoes actually cool the planet with their eruptions if they are big enough (just read up on Pinatubo). On top of it all, most of the cycles governing the planet are probably way longer that our recorded history and thus no amount of number crunching can predict them. We should just concentrate on pollution reduction and try to reduce our emissions of all kinds rather than panic at the sight of the global warning non-science pandemic!

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  5. 5. The iceman cometh 4:50 pm 04/21/2010

    Climate change is not the answer to every problem. To invoke it to account for earthquakes or volcanism shows a gross lack of understanding of the origin of these phenomena, and of the forces involved. If there were any substance in the assertion, there would be evidence for a different level of tectonic activity during the ice ages. I challenge the authors of this nonsense to produce a scrap of evidence that such changes occured.

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  6. 6. morebhp 5:28 pm 04/21/2010

    I see "may" and "could" used quite a bit in this short little essay. This is pretty common for these weekly "climate change" entries. Lots of wild speculation and dubious conclusions. This is science? Frankly I find it shocking just how many people, while claiming they are educated, have bit on this overtly political tool recently dubbed "climate change". Do we need to see any more evidence that this is merely an attempted money grab by poorer nations? Its so patently obvious.

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  7. 7. hugopenteado 6:34 pm 04/21/2010

    About morebh[ comment: you prefer to die instead of face horrible doubts about systemic consequences of human activities. If these doubts are confirmed, humankind will disappear from Earth surface. It is a logic approach: I died? No, I am writing now this comments, so I did not die yet. This means will I never die? No. Earth never expelled human race from Earth. Does this mean that this event is impossible?

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  8. 8. hugopenteado 6:35 pm 04/21/2010

    About morebh’s comment: you prefer to die instead of face horrible doubts about systemic consequences of human activities. If these doubts are confirmed, humankind will disappear from Earth surface. It is a logic approach: I died? No, I am writing now this comments, so I did not die yet. This means will I never die? No. Earth never expelled human race from Earth. Does this mean that this event is impossible?

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  9. 9. Soccerdad 9:04 pm 04/21/2010

    And I thought people were just cracking jokes when they were blaming the volcano eruption on global warming. Or is it this headline that’s the real joke?

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  10. 10. andyarok 12:29 am 04/22/2010

    Hey, guys dont you feel the change in temperatures in the past 2-3 years. We in India feel it. My goodness, we never had high 40s in our city to the best of my knowledge.

    And people who say that we are not responsible, where do you think all our emissions are going. Did we have the same amounts in the past.

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  11. 11. jtdwyer 4:45 am 04/22/2010

    andyarok – Yeah, but we think its just because you’re using the wrong kind of thermometers & getting bad data (this is a joke).

    Personally, I don’t notice any significant change, and I’ve been around a long time. Seriously, its possible that our weather is generally more seasonably variable than yours, masking noticeable change. I do know that in the center of the USA I’ve experienced all time record lows & highs of -22 and +108 degrees Fahrenheit, but that was all in the early 1990s. I think most don’t think that individuals’ perceptions of temperature are a reliable indicator. Perhaps your weather is more stable nearer the equator. Have there been any significant changes in the Monsoon season?

    Personally, I have little doubt that the global temperature has been increasing, but I think the future is still unpredictable. Certainly humanity is contributing to atmospheric CO2, but much larger amounts of CO2 are exchanged between soils, minerals atmosphere and oceans, making definitive causal determination extremely difficult.

    One thing I am certain of is that the Human population has increased from about 2.5 billion in 1950 (when I was born) to nearly 7 billion now. Whatever contribution humanity is making to global warming, population growth is a significant contributing factor. As a result, while the causes of global warming, impending food production shortfalls, etc. may be debated endlessly, humanity can significantly improve critical global conditions by finding some way to humanely reduce our population.

    To my knowledge only China has taken effective steps to accomplish this, limiting children to one per couple. While we view this as an assault on our personal liberties, the alternative may be increasing human suffering as the death rate approaches the birth rate.

    I was wondering if many in India have recognized that the population is perhaps the most critical issue facing humanity? If so, are there suggestions being made on how to humanely achieve population reduction?

    Of course we can continue to ignore this problem, but that will only result in increasing suffering for our children. Thanks in advance.

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  12. 12. hugopenteado 5:14 pm 04/22/2010

    Yes, andyarok, in So Paulo we had 50 days of restless rain, in 2008 Floripa had 14 weekends of restless rain, and recently Rio de Janeiro.
    And about the huge ice melting opening new routes to the ships? Volcanos can do in one time what mankind did in 200 years. That only serves to show how vulnerable we are and proves how is non-understandable our total lack of humility, solidarity and generosity.

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  13. 13. Eclipse 8:02 pm 04/22/2010

    @ Doug I
    No, the sociopaths are the ones denying the basic physics and chemistry of Co2 interactions with long-wave length energy and the obvious and measurable changes this is causing in our environment. The sociopaths are the ones that put their investments in fossil fuels ahead of the 200 thousand people that die from global warming each year, and the untold millions, possibly billions, that might die from global warming related weather disasters, crop failures, and even global warming induced resource wars (over water or food?)

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  14. 14. Eclipse 8:03 pm 04/22/2010

    @ Francois Theriault: Volcanoes cool the climate do they? Want to qualify that a bit with the admission that periods of high volcanism have in the past INCREASED global warming, and one time may have even saved earth from a global freeze? "Over 4 to 30 million years, enough CO2 and methane, mainly emitted by volcanoes, would accumulate to finally cause enough greenhouse effect to make surface ice melt in the tropics until a band of permanently ice-free land and water developed;[58]"
    http://tinyurl.com/24vmjsm
    Yes science admits BIG eruptions cause global dimming, but to try and cast *all* volcanic activity as combating global warming is just plain dishonest. Volcanoes can release Co2 without as much cloud emissions and particulate action as is happening over Iceland. Periods of high volcanic activity in the deep past have lead to natural periods of global warming. And no, climatologist don’t deny any of this… they are quite aware of volcanoes, global dimming, previous warming and cooling phases of the earth’s climate, and James Hansen even MODELLED and PREDICTED a Mt Pinatubo event in one of his climate models!

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  15. 15. Conrad 1:06 pm 04/23/2010

    There is plenty of evidence that shows how changes in surface pressure on the earth can induce earthquakes. Large dams that impound large amounts of water have shown this many times over many years. In the US, good examples are Lake mead behind the Hoover Dam and Lake Powell behind the Glen Canyon Dam. In China the 3 Rivers Gorge is another prime example.

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  16. 16. jtdwyer 10:56 am 04/24/2010

    Conrad – That’s right. The only question is how much pressure inducing mass must be removed from how large an area how quickly to produce major earthquakes and volcanic eruptions?

    I could be wrong, but I think that if the ice sheets’ mass at the end of an ice age is compared to existing ice sheets or lakes, there’s little chance that any current release could match those that occurred following an ice age, unless it occurred extremely quickly.

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  17. 17. andyarok 12:58 pm 04/28/2010

    @jtdwyer
    Yep dude. I agree with the population thing completely. The thing I hate the most is that the educated seems to be more stubborn to have many children. Ridiculous.

    You know a 2 month old cub was killed in an urban area by stoning, to be fair to the cub it was barely able to move fast let alone go on a hunting spree.

    Regarding the climate, Monsoon has changed a bit and we would have heavy rains in the month of November and December, so heavy that schools and colleges would be closed. But right now it seldom rains here. Though it is too early to conclude based on last 3-4 years yet I speculate it on Global Warming. If not man made, then we should look out for other alternatives that makes sure other species dont suffer by just our very existence.

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