A link between climate, ice melt, and volcanic eruptions is found

When the ice melts, the Earth spews fire

GEOMAR researchers discover a link between climate and volcanic eruptions

It has long been known that volcanic activity can cause short-term variations in climate. Now, researchers at the GEOMAR Helmholtz Centre for Ocean Research Kiel (Germany), together with colleagues from Harvard University (Cambridge, Massachusetts, USA) have found evidence that the reverse process also occurs: Climate affects volcanic activity. Their study is now online in the international journal “Geology”.

In 1991, it was a disaster for the villages nearby the erupting Philippine volcano Pinatubo. But the effects were felt even as far away as Europe. The volcano threw up many tons of ash and other particles into the atmosphere causing less sunlight than usual to reach the Earth’s surface. For the first few years after the eruption, global temperatures dropped by half a degree. In general, volcanic eruptions can have a strong short-term impact on climate. Conversely, the idea that climate may also affect volcanic eruptions on a global scale and over long periods of time is completely new. Researchers at GEOMAR Helmholtz Centre for Ocean Research Kiel (Germany) and Harvard University in Massachusetts (USA) have now found strong evidence for this relationship from major volcanic eruptions around the Pacific Ocean over the past 1 million years. They have presented their results in the latest issue of the international journal “Geology”.

The basic evidence for the discovery came from the work of the Collaborative Research Centre “Fluids and Volatiles in Subduction Zones (SFB 574). For more than ten years the project has been extensively exploring volcanoes of Central America. “Among others pieces of evidence, we have observations of ash layers in the seabed and have reconstructed the history of volcanic eruptions for the past 460,000 years,” says GEOMAR volcanologist Dr Steffen Kutterolf, who has been with SFB 574 since its founding. Particular patterns started to appear. “There were periods when we found significantly more large eruptions than in others” says Kutterolf, the lead author of the Geology article.After comparing these patterns with the climate history, there was an amazing match. The periods of high volcanic activity followed fast, global temperature increases and associated rapid ice melting.

To expand the scope of the discoveries, Dr Kutterolf and his colleagues studied other cores from the entire Pacific region. These cores had been collected as part of the International Integrated Ocean Drilling Program (IODP) and its predecessor programmes. They record more than a million years of the Earth’s history. “In fact, we found the same pattern from these cores as in Central America” says geophysicist Dr Marion Jegen from GEOMAR, who also participated in the recent study.Together with colleagues at Harvard University, the geologists and geophysicists searched for a possible explanation. They found it with the help of geological computer models. “In times of global warming, the glaciers are melting on the continents relatively quickly. At the same time the sea level rises. The weight on the continents decreases, while the weight on the oceanic tectonic plates increases. Thus, the stress changes within in the earth to open more routes for ascending magma” says Dr Jegen.

The rate of global cooling at the end of the warm phases is much slower, so there are less dramatic stress changes during these times. “If you follow the natural climate cycles, we are currently at the end of a really warm phase. Therefore, things are volcanically quieter now. The impact from man-made warming is still unclear based on our current understanding” says Dr Kutterolf. The next step is to investigate shorter-term historical variations to better understand implications for the present day.

Reference:

Kutterolf, S., M. Jegen, J. X. Mitrovica, T. Kwasnitschka, A. Freundt, P. J. Huybers (2012): A detection of Milankovitch frequencies in global volcanic activity. Geology, G33419.1, http://dx.doi.org/10.1130/G33419.1

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Truthseeker

Not a model in sight … must be real science.

GlynnMhor

It does make sense that a reduced overburden load of ice might increase the chances of an eruption. Even for Mt St Helen’s one of the videos shows pretty clearly that the trigger for the blast was a landslide that removed considerable weight from the top of the mountain.
It’s a fascinating area of research, though it does not really say much about anthropogenic influences.

Stephen Singer

@Truthseeker
You better go back and reread that article. They used ‘geological computer models’ to examine their theory.

Truthseeker says: “Not a model in sight … must be real science.”
– – –
You seem to have missed this sentence:
“They found it with the help of geological computer models.”

Stephen Singer

Just read the abstract of this study. They mention detection of ‘Milankovitch periodicities in volcanic output across the Pleistocene-Holocene ice age”. It’s curious that the above article does not mention this at all.

I wonder if the unintuitive sea level decrease from ice loss due to mass loss near the volume of ice loss was taken into consideration in their models?
http://motls.blogspot.ca/2010/06/if-greenland-melted-sea-level-in.html

cloa5132013

I saw this first referred to in Gizmag and I though I should suggest the story but Watts got in first.
No doubt some alarmist is going to jump on it ignoring the Milankovitch frequencies given that the Milankovitch cycle is about 26000 years.
Geological computer models to come to a reason. I read the reference and how did they measure volcanic activity given most of its in the deep oceans and if its just land than it can’t be Isostatic geological decompression as that is supposed to be the oceans relatively rising. So unless Magna is flowing all the way under the deep oceans to the land than its a big fail as a theory.

otsar

Once upon a time I told my geophysics prof that I thought that rapid changes in the earth’s magnetic field could induce heating of ferromagnetic and low resistivity rocks by eddy losses, in other words magnetic induction heating. He said it was probably an insignificant factor. Someone with time and means should have a look at this if it has not been done already. A warming Sun exciting the Earth’s AC magnetic field ??

Felix

@Truthseeker, you’re obviously trying to be ironic, but the last two paras are models. Any half-decent theory is a model, even if it’s completely wrong. Your way of telling whether or not it’s real science is a model! Science, and anything in real life, is replete with models. And imaginary life is itself a model! People are model-making machines.

davidmhoffer

“If you follow the natural climate cycles, we are currently at the end of a really warm phase.
>>>>>>>>>>>>>>>>>>>>
Will the journal editor be forced to resign and apologize to Kevin Trenberth for allowing this sentence through?

Lee from WA

Aren’t volcanic eruptions supposed to cool the earth? Sounds like another negative feedback: Catastrophic eruptions reduce the effects of catastrophic global warming. 🙂

tgmccoy

On Mt. St.Helens. I was there for all of it from the inital eruptions to the May 18th blast and
aftermath. The Land slide was the northeast side- Goat Rocks. I flew a survey around the mountain the day before. The rocks were clearly bulging. I mean clearly. Goat rocks were
the result of the previous eruptive explosive period, They were plugging the vent, while some
of the energy went upward most went to the side, the explosion of the volcano went the way of least resistance to the side. The blast created the landslide….and lots of Andesite….

John West

Well, we have evidence of isostactic rebound still occurring from the last ice age and it seems reasonable that we’d be at a much slower rate now than say 4k years ago give or take 3.6k years. It also seems reasonable that continental masses that are basically floating on molten rock if rising would effect magma “currents” especially at subduction zones where various densities are already providing upward pressure. I also think they demonstrate reasonableness with the statement: “If you follow the natural climate cycles, we are currently at the end of a really warm phase.”
Looks to me like we may have some real science going on here even with the computer modeling.

TimiBoy

Well whaddya know, a Negative Feedback!

RoHa

I will not quote Robert Frost.
I will not quote Robert Frost.
I will not quote Robert Frost.

This one’s has the cause and effects in the proper order, unlike CO2 and Temperature rise. I also like the author’s informative comment ‘if you follow natural climate cycles’. Scientists with a more Paleo view of climate often do not have the skewed context of our modern day short sighted computer modelers. Of course the door is open to study man-made warming effects 🙂
“If you follow the natural climate cycles, we are currently at the end of a really warm phase. Therefore, things are volcanically quieter now. The impact from man-made warming is still unclear based on our current understanding” says Dr Kutterolf.

RoHa

Incidentally, it has been Doomsday for sixteen hours here in Brisbane. The sky is a bit cloudy, but, as far as I can tell, the world hasn’t come to an end yet. Still time, though.

2kevin

Weren’t we all laughing at the article around the time of the Icelandic eruptions which claimed the exact same thing?

John F. Hultquist

Explosive volcanic eruptions are associated with subducting plates. For example, off the coast of Washington State there is the Juan de Fuca Plate and Mt. St. Helens is about 90 miles from the coast. In contrast, Kilauea Volcano (Hawaii) is much less explosive. The timing of explosive eruptions ought to be related to the rate and angle of descent of the subducting plate. The rate of plate movements appears to be controlled by the production of magma underneath spreading centers or ridges.
The provided link is to an abstract. Full PDF is a $25 one day deal. While I am wondering what the full paper says – I can wait.

My gut reaction is akin to what I felt when I first heard about Louis Alvarez and the K-T asteroid impact. My first reaction then was, “The dinosaurs were dying out at the end of the Cretaceous. It’s mighty coincidental that they were finished off by an impact then.” Only by a change of perspective do you examine your logical trail and realize, “No, we were taught that things happened gradually, so we had to believe dinosaurs were dying out prior to extinction.”
So with that lesson in paradigm shift in mind, let’s evaluate what is presented here. Raise the water lever by melting the ice, their by raise the water pressure at the sea floor trenches — 300 ft in 15,000 ft? Two Percent?
When it comes to plausible mechanisms, however, I can make a very good case for climate induced volcanism at the COLDEST part of the ice age, not the warmest of the interglacial. Consider this…. At the closest point, we have ice sheets bearing down on the cratons of the world. Sea level is very low with beaches at the continental margins. Every volcanic island and seamount now has 100 m + of its once submerged skirt above water. The stresses on the flanks of these active / dormant / extinct volcanos is much higher than when formed. Large-run-out-landslides will become more frequent. Each on exposing the core of the volcanos to less overburden pressure inducing eruptions. Imagine the sloughing of the north slope of Mt. St. Helens causing its eruption.
Now transport that landslide process to Oahu and Molokai as well as Fiji, Java, Martinique, Monserrat, Marianas, Solomon Is., Aleutians, Philippians, … there are hundreds of potentially eruptive islands. These seamount and volcanic islands might be especially susceptible to landslides because a large part of them are composed of underwater erupted and cooled pillow lava that can be thought of as watermelon sized ball-bearings upon which the dry land rests.
True, these volcanos are basaltic and are not generally as explosive as the andesitic St. Helens, but hot rock and ocean water may make their own kind of fire works.
I’ve read and heard about these subsea runout landslides, but until now I had not considered that they might be triggered by sea drops, but it now seems inevitable.
So the paradigm shift I have made tonight is that climate change CAN cause a world-wide increase in volcanism. The trouble is, I can much more easily believe a sea-level low stand causing landslides as the volcanic trigger than a sea-level high stand.

Mike McMillan

Interesting speculation, but we wouldn’t see any effect for thousands of years.
woodfortrees.org doesn’t have this dataset up yet, so it’s hard to confirm.

@RoHa. Good to know Brisbane is still there. However, some people believe that the end of the world will happen at the exact time of the winter solstice: Dec, 21, 2012 at 11:12 UTC.
Or as I write it: 121221.1112, a eerie collection of 1s, 2s and no other digit.
How did the Mayans know we’d be measuring time from Greenwich, England? Spooky.
Reminds me of Apollo 13.
The mission’s launch date written numerically was 4-11-70; add the digits to get 13.
Lift off was Wed. April 11, 13:13 Houston time.
Two days after liftoff, the Oxygen tank blew up. April 13.
Yes, Friday the 13th.
No, it was NOT a Hollywood script. It was real life.
Ok…. LATER, it became a hollywood movie — and a pretty good one.
Back to the clock… 3 hrs and 42 minutes to go.
“Now I lay me down to sleep….”

Tectonic activity in the North Atlantic and Central Pacific can be directly related to climate (temperature) changes
http://www.vukcevic.talktalk.net/CET-NAP.htm
http://www.vukcevic.talktalk.net/ENSO.htm
When oscillations in the geomagnetic field are combined with solar oscillations, relatively good approximation of the natural variability is obtained:
http://www.vukcevic.talktalk.net/EarthNV.htm

The periods of high volcanic activity followed fast, global temperature increases and associated rapid ice melting.

Gaia at work?

Mike Bromley the Canucklehead

My spidey-sense is tingling, and this is not a good thing. Call me cynical along with my sceptical side, but this seems like a grant-grabbing preamble to a fresh litany of things caused by climate change. If that is the case, in reality, we are all doomed because EVERYTHING is caused by climate change. And because climate change IS, that is metaphysically, (no denier here), then sooner or later it will cause our demise, or some other side-effect which will tip the balance. The science, therefore, is settled /sarc.

John R T

” A detection of Milankovitch frequencies in global volcanic activity.”

Kev-in-Uk

Is there a non paywalled version somewhere? My gut feeling is that this is likely to be fanciful interpretation of geological ‘noise’. I do accept that ice age mass will likely affect crustal/tectonic stresses, etc – but remember that these stresses are built up slowly as the ice mass increases, and decrease slowly as it melts. Consequently, I don’t really see how major faults and associated volcanic outpourings will show an obvious ‘peaking’ over and above normal constant (but naturally erratic) movement of faults and other tectonic activity. From the abstract, I can’t really see that a direct cause/correlation relationship would be easy to establish and I would like to see how they derived their statistical significance!
On the modeling side, I wonder what they modeled and how!

There is also intriguing correlation between the Ap index and volcanic activity in the N. Hemisphere
http://www.vukcevic.talktalk.net/Ap-VI.htm
Most likely direction: tectonic movements, volcanic activity and geomagnetic index are all affected what is going on deep inside the Earth’s interior.
Why this on the other hand should correlate to the solar activity and consequently transposed into climate change, is a puzzle for the NASA-JPL scientists too:
“Other possibilities are that some other (Earth) core process could be having a more indirect effect on climate, or that an external (e.g. solar) process affects the core and climate simultaneously.
article: “NASA Study Goes to Earth’s Core for Climate Insights”
http://www.nasa.gov/topics/earth/features/earth20110309.html

Ryan

Lapse rate of 1Celsius per 100m. So you’d need a hell of a lot of warming to melt significant ice at the top of a volcano. Anyway, if a volcano went off, the dust particles would cause cooling, thus protecting all the other volcanoes.
Sounds very ill thought out to me.

I think I was the first to suggest a link in March 2011 Global Warming and Earthquakes

Stephen Wilde

More likely, average global volcanicity stays much the same but when the ice builds up on the continental land masses there is more activity under volcanic islands in the oceans and when the ice declines there is more activity under the continental land masses.

John R McDougall

Correlation/Causation????

Otter

‘Things are quieter now’?
Then why does a site that tracks these things, say there’s too much volcanic activity to possibly post it all? http://earthquake-report.com/2012/12/17/volcano-activity-of-december-17-2012/
And why does it seem to tie in so nicely with changes in the Sun, ie, the sleeping sun?

William

The alleged mechanism is not correct. A special solar cycle change causes the cyclic increases in volcanic activity. Note solar activity in the later half of the 20th century has the highest in 11,000 years and the duration of the high activity was the longest in 11,000 years. (It appears if I understand what is happening currently happening to the sun now, that we are going to be able to observe what causes a Heinrich event.)
The forcing mechanism that causes unexplained cyclic changes to ocean level (the amount of ocean level change is more than can be explained by ice sheet melting and ice sheet forming) is a cyclic change in the sun not insolation at high northern latitudes (N65) caused by orbital changes.
There are no orbital changes that can cause a 10 to 15 m change in ocean level about every 6000 years. (see paper linked to below).
The solar changes do also cause the planet to warm and cool by both direct (Svensmark’s mechanism) and indirect mechanisms (the solar change cause an abrupt change to the geomagnetic field which in turn affects planetary temperature by Svensmark mechanism). The geomagnetic field changes can affect planetary temperature for hundreds or thousands of years depending on the magnitude of the change.
A observation that supports the assertion that solar changes cause an increase in volcanic activity and an abrupt change to the geomagnetic field is the finding that there is an increase in volcanic activity when during solar magnetic cycle minimums. The mechanism is such that the effect is significantly larger when there is an abrupt change from a period of very, very, high solar magnetic cycles to a Maunder minimum. This happens with a periodicity of roughly 6000 years, however, the affect is amplified or inhibited by the orbital configuration at the time of the solar magnetic cycle slow down and the time of the solar magnetic cycle restart. The Heinrich event is caused by a series of solar events that occur when the solar magnetic cycle restarts.
http://geochemistry.usask.ca/bill/courses/International%20Field%20Studies/Sea%20level.pdf
“… the pre-Last Glacial Maximum (pre-LGM) is characterized by substantial fluctuations in sea level of 10 to 15 m about every 6000 years. The timing of these rapid change events during oxygen isotope stage 3 (OIS-3) apparently coincides with Heinrich ice-rafting events recorded in North Atlantic sediments (61), which suggest that they reflect major ice discharges from continent-based or shelf grounded ice sheets (62). Of note is that sea level falls during this period occur in similarly short time intervals and the ice accumulation also appears to have been a rapid process (39).
“Volcanic eruptions and solar activity” by Richard Stothers
http://adsabs.harvard.edu/abs/1989JGR....9417371S
The historical record of large volcanic eruptions from 1500 to 1980 is subjected to detailed time series analysis. In two weak but probably statistically significant periodicities of about 11 and 80 yr, the frequency of volcanic eruptions increases (decreases) slightly around the times of solar minimum (maximum). Time series analysis of the volcanogenic acidities in a deep ice core from Greenland reveals several very long periods ranging from about 80 to about 350 yr which are similar to the very slow solar cycles previously detected in auroral and C-14 records. Solar flares may cause changes in atmospheric circulation patterns that abruptly alter the earth’s spin. The resulting jolt probably triggers small earthquakes which affect volcanism. (My comment. This mechanism guess is not correct.)
http://adsabs.harvard.edu/abs/2002AGUFMPP61A0298A
The Role of Explosive Volcanism During the Cool Maunder Minimum
The Dalton Minimum was a period of low solar activity, named for the English meteorologist John Dalton, lasting from about 1790 to 1830.[1] Like the Maunder Minimum and Spörer Minimum, the Dalton Minimum coincided with a period of lower-than-average global temperatures. The Oberlach Station in Germany, for example, experienced a 2.0° C decline over 20 years.[2] The Year Without a Summer, in 1816, also occurred during the Dalton Minimum. The precise cause of the lower-than-average temperatures during this period is not well understood. Recent papers have suggested that a rise in volcanism was largely responsible for the cooling trend.[3] (William: The signficant increase in volcanic activity during the Maunder minimum was caused by the sun. There was no massive increase or decrease in the ice sheets during the Maunder minimum period.)
William: Another observation that supports the assertion that solar changes are causing the cyclic increase in volcanic activity is finding there is a simultaneous increase in volcanic eruptions in both hemispheres. There are not ice sheet changes in both hemispheres that correlate with the volcanic regions.
http://www.pnas.org/content/101/17/6341.full#otherarticles
Analyzing data from our optical dust logger, we find that volcanic ash layers from the Siple Dome (Antarctica) borehole are simultaneous (with >99% rejection of the null hypothesis) with the onset of millennium-timescale cooling recorded at Greenland Ice Sheet Project 2 (GISP2; Greenland). These data are the best evidence yet for a causal connection between volcanism and millennial climate change and lead to possibilities of a direct causal relationship. Evidence has been accumulating for decades that volcanic eruptions can perturb climate and possibly affect it on long timescales and that volcanism may respond to climate change. If rapid climate change can induce volcanism, this result could be further evidence of a southern-lead North–South climate asynchrony. Alternatively, a volcanic-forcing viewpoint is of particular interest because of the high correlation and relative timing of the events, and it may involve a scenario in which volcanic ash and sulfate abruptly increase the soluble iron in large surface areas of the nutrient-limited Southern Ocean, stimulate growth of phytoplankton, which enhance volcanic effects on planetary albedo and the global carbon cycle, and trigger northern millennial cooling. Large global temperature swings could be limited by feedback within the volcano–climate system. (William: This guess concerning the mechanism is not correct.)

DirkH

Stephen Rasey says:
December 20, 2012 at 10:57 pm

“When it comes to plausible mechanisms, however, I can make a very good case for climate induced volcanism at the COLDEST part of the ice age, not the warmest of the interglacial. Consider this…. At the closest point, we have ice sheets bearing down on the cratons of the world. Sea level is very low with beaches at the continental margins. Every volcanic island and seamount now has 100 m + of its once submerged skirt above water. The stresses on the flanks of these active / dormant / extinct volcanos is much higher than when formed.”

Very good. Obviously Kutterolf wanted to get in on the Global Warming action, I guess CORDIS is as full of EU dough for alarmist research as ever. Kutterolf knows he describes Milankovicz warming but an EU bureaucrat is not intelligent enough to tell the difference. Your remark kinda destroys his correlation – causation tale.

P. Solar

The finding of correlation is very interesting but correlation is not causation.
“Conversely, the idea that climate may also affect volcanic eruptions on a global scale and over long periods of time is completely new.”
Unfortunately pay-walled so no idea whether is is well founded or not. Since global warming causes everything from malaria to blindness in babies, why not volcanoes.
Gravitational forces on the solid earth have varying amplitudes dependant on relative positions of the planets. If they find periodic repetition in volcanic erruptions that may suggest a physical link. I’m sure Tallbloke and others will find this study interesting
Milankovich frequencies are extra terrestrial in origin , this may be a first step to a recognition of extra-terrestrial influences on climate.

DirkH

Roger Knights says:
December 20, 2012 at 11:57 pm


The periods of high volcanic activity followed fast, global temperature increases and associated rapid ice melting.
Gaia at work?”

If Gaia is intelligent, why isn’t the Sun? And if the sun is intelligent, why isn’t it responsible for climate cycles? General question to Gaia believers. Can be extended to include the Galaxy, the Galaxy cluster and the universe, of course. (One reason that they assign the intelligence attribute to the Earth is of course Isaac Asimov’s Gaia story.)
https://en.wikipedia.org/wiki/Gaia_%28Foundation_universe%29
Interestingly, Asimov has no problems with an intelligent planet and an intelligent Galaxy but skips the step of an intelligent sun.

William

The following are links to papers supports my above comments.
(I have been working away at the astrophysical end to explain how the sun could cause the observed cyclic magnetic field changes and have had a couple of significant breakthroughs. I have the basic outline of the solution. The next step is to work out the details and to gather data and papers to support the assertion. I will have sometime next year to work on this more or less full time. The nature of the problem requires assistance from a team of specialists which will be a challenge.
It is interesting that each field has a group of scientists that support a piece of the solution.i.e.When I say above that I have found the solution, I am really only putting together different partial solutions that are outlined in published papers from the different fields. The problem solving technique is somewhat like putting the pieces together in jigsaw puzzle. What I am adding to the problem solving is I am moving into multiple fields.)
Are there connections between the Earth’s magnetic
field and climate? Vincent Courtillot, Yves Gallet, Jean-Louis Le Mouël,
Frédéric Fluteau, Agnès Genevey
We review evidence for correlations which could suggest such (causal or non-causal) connections at various time scales (recent secular variation approx 10–100 yr, historical and archeomagnetic change appox. 100–5000 yr, and excursions and reversals approx. 10^3–10^6 yr), and attempt to suggest mechanisms. Evidence for correlations, which invoke Milankovic forcing in the core, either directly or through changes in ice distribution and moments of inertia of the Earth, is still tenuous. Correlation between decadal changes in amplitude of geomagnetic variations of external origin, solar irradiance and global temperature is stronger. It suggests that solar irradiance could have been a major forcing function of climate until the mid-1980s, when “anomalous” warming becomes apparent. The most intriguing feature may be the recently proposed archeomagnetic jerks, i.e. fairly abrupt (approx. 100 yr long) geomagnetic field variations found at irregular intervals over the past few millennia, using the archeological record from Europe to the Middle East. These seem to correlate with significant climatic events in the eastern North Atlantic region. A proposed mechanism involves variations in the geometry of the geomagnetic field (f.i. tilt of the dipole to lower latitudes), resulting in enhanced cosmic-ray induced nucleation of clouds. No forcing factor, be it changes in CO2 concentration in the atmosphere or changes in cosmic ray flux modulated by solar activity and geomagnetism, or possibly other factors, can at present be neglected or shown to be the overwhelming single driver of climate change in past centuries. Intensive data acquisition is required to further probe indications that the Earth’s and Sun’s magnetic fields may have significant bearing on climate change at certain time scales.
http://sciences.blogs.liberation.fr/home/files/Courtillot07EPSL.pdf
http://geosci.uchicago.edu/~rtp1/BardPapers/responseCourtillotEPSL07.pdf
Response to Comment on “Are there connections between Earth’s magnetic field and climate?, Earth Planet. Sci. Lett., 253, 328–339, 2007” by Bard, E., and Delaygue, M., Earth Planet. Sci. Lett., in press, 2007
Also, we wish to recall that evidence of a correlation between archeomagnetic jerks and
cooling events (in a region extending from the eastern North Atlantic to the Middle East) now covers a period of 5 millenia and involves 10 events (see f.i. Figure 1 of Gallet and Genevey, 2007). The climatic record uses a combination of results from Bond et al (2001), history of Swiss glaciers (Holzhauser et al, 2005) and historical accounts reviewed by Le Roy Ladurie (2004). Recent high-resolution paleomagnetic records (e.g. Snowball and Sandgren, 2004; St-Onge et al., 2003) and global geomagnetic field modeling (Korte and Constable, 2006) support the idea that part of the centennial-scale fluctuations in 14C production may have been influenced by previously unmodeled rapid dipole field variations. In any case, the relationship between climate, the Sun and the geomagnetic field could be more complex than previously imagined. And the previous points allow the possibility for some connection between the geomagnetic field and climate over these time scales.

Peter Miller

My first thought on reading this was: BS
I read the article again and noted that the change in the level of stress was supposed to accelerate volcanic activity. I guess that makes sense as the glaciers were often over 1.5kms thick and that’s a lot of weight, which would be removed during glacial melt.
Then I thought of little Iceland and its troublesome volcanoes. About 60% of Iceland is covered with lava flows and volcanic ash fields, which are less than three million years old. Also, Iceland is currently responsible for around one third of the world’s volcanic activity. Iceland’s volcanoes and the closing of the Panama Isthmus may be the reasons behind the Pleistocene Ice Age, which started ~2.65 million years ago.
Most of the world’s volcanoes are located at high altitudes or high latitudes. During ice ages they would likely have been covered by thick sheets of glacial ice. When the ice began to melt, the downward pressure of their weight would decrease, thus making it easier for magma to ascend to surface through cracks and fractures. This process would cause a modest short term acceleration and deceleration in volcanic activity, but not a long term change in it.
Another factor to consider is that when volcanoes erupt under ice, they create much very more ash than usual and that in turn cools the planet. The small ash eruption of Eyjafjallajökull in 2010 in Iceland caused havoc to North Atlantic and European air travel.
Three of the most famous of Iceland’s sub-glacial volcanoes are located the under the Vatnajökull glacier. When and if any of the Grímsvötn, Öraefajökull and Bardarbunga volcanoes beneath this glacier erupt (every few hundred years), it makes the Eyjafjallajökull eruption look utterly puny.
Magma + air = Magma
Magma + ice = Ash
I had never thought of this before, namely that sub-glacial volcanic eruptions may have a big impact on prolonging ice ages due to the amount of ash they spew into the atmosphere.

Kaboom

It is not very plausible to consider the very small changes in sea level and ice loss in the current, highly stable climate era a significant trigger factor for eruptions. There may be more value to the hypothesis during times of rapid climate change when ice sheets build up or melt off at a fast pace. However these events should be clearly correlating with geological evidence.

mpainter

“If you follow the natural climate cycles, we are currently at the end of a really warm phase. ” says Dr. Kutterolf, who apparently has not been properly indoctrinated. No more funding for you.

“Thus, the stress changes within in the earth to open more routes for ascending magma” says Dr Jegen.
What makes the magma ascend? You have not completed the analysis of the full cycle of change, you are referring to only selected parts.
Why does not tidal change, which alters water weight distribution daily, also cause stress changes and fractures?
BTW, classical subduction geology and volcano formation mechnaisms has is own challengers, see e.g. the expanding earth symposium in http://www.utas.edu.au/codes/publications/publications-for-sale
Another case of the establishment trying to lock out dissent.

amoorhouse

Excuse me if I am being thick here, but if Mt. Pinatubo dropped global temps for the next few years after 1991 by 0.5 degrees then this would have put the 90’s in the same temperature give or take that has existed since 1998 and indeed has existed to the present day. Therefore the standstill in global warming could be said to be (Pinatubo aside) roughly constant since 1991.

FundMe

Mt St Helens under a mile of ice..no one would even notice that it had erupted. No sea bed ash nothing in the cores. All would seem quiet under miles of ice.

Gail Combs
JimG132

“It has long been known that volcanic activity can cause short-term variations in climate.”
A nice debunking of this conventional wisdom: http://wattsupwiththat.com/2012/07/30/new-data-old-claims-about-volcanoes/

George V

Concur with @Mike Bromley the Canucklehead. The message will be that now in addition to storms, droughts, rain, wind, etc., driving your auto and using electricity causes extreme volcanoes.

Bruce Cobb

“The impact from man-made warming is still unclear based on our current understanding” says Dr Kutterolf. The next step is to investigate shorter-term historical variations to better understand implications for the present day.”
There it is! I was holding my breath through the article waiting for the usual bowing and scraping before the god of Warmism, and appeal for more funding so that the manmade cause of volcanoes could be “discovered”. All is right with the world.

Gamecock

Stephen Rasey says:
December 20, 2012 at 10:57 pm
Every volcanic island and seamount now has 100 m + of its once submerged skirt above water. The stresses on the flanks of these active / dormant / extinct volcanos is much higher than when formed.
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Seamounts in the Hawaiin chain are way off the volcanic hotspot, and not subject to further eruption.

A C Osborn

Solar Activity causes both Earthquakes and Eruptions, who needs less Ice?