Posted on 12/24/2012 9:37:21 AM PST by Errant
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.
There is actual volcanic debris along I-40 in the interior of California also. I saw it myself.
If you are talking about my statement about the center of North America, I was not talking about the interior of California, or the Yellowstone Caldera. Having spent time in Iowa, my concept of center of North America is from around there and northward. Yellowstone Caldera is in the Rocky Mountains which is entirely different from the center of our country and Canada which in eons past was a great shallow inland sea, not home to volcanic activity. Also, I am very aware of Yellowstone as my father wrote a fiction book about a major eruption of Yellowstone in our own times.
If not manipulated in any way, (I am at a loss, although the time of year is summer ?) or Planet X’s Sun making a visit. That dude in Australia keeps saying it’s coming, Nibiru is coming. Extreme refraction? I’m just blabbering.
Very windy and looks kinda like a front where the rays originate. I'm a little confused by what I'm seeing after he swings the camera about 180 though; looks like the setting sun, but maybe a cloud on the opposite horizon being lit up by the rays?
Awesome!
Ha! Don't tempt me! lol
I re-eyeballed the earthquake chart. Looks like maybe an eight year cycle, if one could be established at all with such a small amount of data available...
About 100 miles north of there is another strange area with possible volcanic origins and this area has been in the news as the location of recent minor earthquake swarms.
My pet theory for a very long time has been that tidal forces from the sun/moon/earth orbits act on the Earth’s core, which is believed to be mostly solid iron the size of the moon, causing frictional heating that builds up over a period of time. Another effect from this, which I won’t go into much now, is a kind of pumping action occurs (I don’t buy the conventional convection plume theory).
So after a period of time, say every 12K years, this excess heat eventually causes a weakening of the lithosphere and pressure waves from the core’s pumping action opens fissures through which extra molten material finds its way through to the surface in the form of what we call plumes and divergent tectonic plate boundary zones. IMO, this is the simplest explanation and makes the most sense.
Scientists believe frictional heating from tidal force occurs with other bodies in our solar system, such as the moon IO orbiting the planet Jupiter, and a number of icy moons in the solar system with cryovolcanoes.
Active Volcanoes of Our Solar System - Activity Occurs on Earth and on the Moons of a Few Planets
In my Errant opinion, this is strong evidence that a similar process (except the Earth's solid central core is one of the main elements here), is what's occurring within the Earth’s interior and may explain what drives the Earth back into ice ages, even during warm periods (from the increased ash/SO2/moisture released into the atmosphere from increased volcanic activity).
Keeping in mind this is a complex world, there are other contributing factors in climatic change such as asteroid/comet impacts, solar output variations, changes in the Earth's orbit and inclination through precession, and etc.
It has been pretty thoroughly discussed at Catastrophism that the Younger Dryas was probably caused by asteroid/comet strikes along the Canadian border and perhaps in northern Europe. A well researched book by Firestone, et al. lays out this theory in detail. SC: Give him the reference please.
Once you have checked this out, see how it would affect your theorizing. I am inclined to think that Ice Ages are cause by megavolcanos and large asteroids/comets.
The Long Valley caldera activity was over 700,000 year ago, and the last major Yellowstone was about 640,000. However, Yellowstone has been blowing its top with major excess for 16 or 18 million years, as the magma plume has advanced to the east under the continent. National Geographic had a detailed article on this not too long ago with excellent maps and drawings.
Btw, while I used a 12K year cycle in the description above, my thoughts are that this is a continuous and complex process with super cycles matching the start of ice ages brought on by a massive increase in volcanic activity around the planet, and prior warm periods somehow a part of the cycle.
I know, it all needs a lot more thought/study, but I'm pretty convinced the main mechanism is tidal with the core playing a major role. Of course there are other factors (e.g., impacts, orbits, solar).
A pan of water on a hot burner eventually boils the water away and the pan melts. Now I know the cause for the water leaving the pan was global warming.
When all the ballyhoo was going on about drowning polar bears, there was submarine volcanic activity in the Arctic Ocean.
Blaming volcanic activity on melting ice is bassackward, imho.
Many moons ago, when people considered the internal heat of this planet the result of nuclear reactions at the core, a colleague and I postulated that the natural reactor at the core would poison itself when the daughter products reached a concentration sufficient to inhibit fission. That concentration (iirc) is fairly low, just a few percent. This would cause a period of quiescence which would allow the material to density stratify (removing daughter products), and then a resurgence when it did, which would account for the cyclical nature of the thermal cycles which drive tectonic activity.
No natural system is ever as 'pretty' as a theory, and the process would be unevenly distributed laterally in the layer of heavy metals near/at the core, but that might account for the thermal pulses apparent over geologic time, delayed and distributed by convection cells in the mantle.
Anyway, melting ice is one symptom of higher heat flow, not the cause thereof. There are other causes, after all, the ice has thermal interfaces on the top as well as the bottom, whereas heat applied from the outside is unlikely to cause volcanic activity without melting a lot more than ice.
The other as yet less than fully understood factor deals with cosmic impacts, and while causation is as easy to blame on cosmic impacts as more humanoid extraterrestrial influences (joking), if one was enough to cause an ELE at the end of the Cretaceous, other, lesser impacts could certainly cause less than ELE climate shifts.
Theory of the possible impact-related formation of the Carolina Bays may account for the Younger Dryas cooling. Either that, or all those Mammoth were cruising the glacial margins in SUVs again. (again, joking).
Melting ice requires the absorbtion of tremendous amounts of latent heat to achieve the phase change, with the effect of cooling surroundings, not heating them. That alone renders the concept that melting ice causes volcanism rather than vice-versa a bit counterintutitve. I would think there are enough examples of alpine glaciers melting prior to eruptions (from increased heat flow from rising magma) to show that cause-effect relationship.
On a global level, volcanism can cause significant atmospheric ash and sulfide levels which can decrease insolation and cause large scale cooling, but again, when the ash settles locally, there is a sufficient albedo change to cause the upper layers of the ice to absorb more heat rather than less, unless the thickness of pyroclastic material is great enough to act as an insulator, a phenomenon often observed in the spring at this latitude with wind-blown sediment, where ice can be preserved into late spring and early summer under a layer of dirt--especially in naturally shaded areas.
For this reason, much like with CO2, I think the researchers may have taken a trailing indicator and attributed causation to it.
Please keep in mind that the evidence of volcanic activity which settled on the ice sheets washed away when they melted. The data subset may be skewed by the lack of preservation of the pyroclastic sediments. The apparent increase may be a question of preservation of ash beds, with those after the ice melted being preserved and those which fell on the ice sheets not.
Solid theory. Thank you. Very interesting.
I wouldn't argue there isn't some internal heat being generated by a nuclear reaction process. I just don't see evidence to support such a process on a massively large enough scale, and one lasting eons that would be needed to cause the amount of change the Earth's geology indicates has occurred throughout its history.
I agree with you on the remainder. I'm trying to better understand how a frozen dry world sitting on top of well insulated heat source, goes about becoming unfrozen in roughly 12K years. Determining how this happens is difficult.
I would imagine heating of the oceans plays a much larger role than heat transfer beneath the continents.
Been rather quiet on the large-quake scale.
Naturally, I’ll respectfully disagree — there’s no possible cause for massive glaciation apart from big impacts from space. Literally nothing else will cause it. I appreciate the deep-seated desire that there’s some kind of classifiable, predictable, cyclical cause, but there just isn’t one.
Even if the crustal displacement or pole shift models had been plausible (most recent advocates of the former are the Flem-Aths, basing their work on that of Charles Hapgood), they amount to trying to tame down catastrophes — look, a way for landmasses to shift into other latitudes with nary a shake or shimmy, barely rattling the dishes in the cupboard.
That said, there’s clearly an altitude shift, such as isostatic rebound when large ice masses melt back into the seas, but the ice didn’t get there gradually over centuries or thousands of years.
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