New evidence that cosmic impact caused Younger Dryas extinctions

Aug 06, 2013 by Marcia Malory report
Climate changes associated with the Younger Dryas, highlighedhere by the light blue bar, include (from top to bottom): cooling and decreased snow accumulation in Greenland, cooling in the tropical Cariaco Basin, and warming in Antarctica. Also shown is the flux of meltwater from the Laurentide Ice Sheet down the St. Lawrence River. Sources: Alley (2000), Lea et al. (2003), EPICA (2004), Licciardi et al. (1999).

(Phys.org) —A period of rapid, intense cooling, known as the Younger Dryas, took place about 13,000 years ago. Scientists think this sudden change in climate caused the extinction of many large mammals, such as the mammoth, and was the reason for the disappearance of North America's Clovis people. According to one hypothesis, a cosmic impact caused the climate to cool. Using data from the Greenland ice core, Michail Petaev and his colleagues at Harvard University have found what appears to be evidence of this impact. Their research appears in the Proceedings of the National Academy of Sciences.

Measurements of in the Greenland ice core show that around 13,000 years ago an episode of rapid cooling, which lasted only about 1,000 years, occurred. During this time, many megafauna became extinct and evidence of the Clovis people, one of the earliest human societies to inhabit the Americas, disappeared from the archeological record.

According to one hypothesis, a cometary airburst triggered massive wildfires, which caused the climate to cool. Many scientists have rejected this hypothesis, citing lack of sufficient evidence, in favor of others. The most widely accepted one says that during the deglaciation process, fresh water from the proglacial lake Agassiz discharged into the Arctic Ocean, altering .

However, Petaev's team says that geomorphological and chronological data do not support this. They claim that evidence for another hypothesis, that the eruption of the Laacher See volcano caused a volcanic winter in the northern hemisphere, is also lacking.

Now, the researchers claim to have uncovered evidence of a cosmic impact at the Younger Dryas boundary. When examining samples from Greenland Ice Sheet Project 2 (GISP2), they found that platinum concentration increased by about 100 times approximately 12,900 years ago.

Platinum/iridium and platinum/aluminum ratios were very high, indicating that the platinum probably did not have a terrestrial source. While most volcanic rocks have high Pt/Ir ratios, their Pt/Al ratios are low. Mantle rocks have low levels of aluminum, but their Pt/Ir ratios are much lower than that measured in the ice core.

On the other hand, Pt/Ir and Pt/Al ratios in magmatic iron meteorites are very high, suggesting that the platinum found in the ice core came from a meteor.

Debris from a cosmic impact would have caused the climate to cool so quickly that species would have been unable to adapt, leading to their extinction. The Clovis people would not have been able to cope with the catastrophic changes to their environment.

The research lends support to recent claims that a sedimentary layer containing iridium grains and glass-like carbon with nanodiamonds, found at many sites around the Younger Dryas boundary, is evidence of a meteor impact.

Petaev and his colleagues caution that future researchers must locate an impact site in order to confirm this hypothesis.

Explore further: Famine in the Horn of Africa (1984) was caused by El Niño and currents in the Indian Ocean

More information: Large Pt anomaly in the Greenland ice core points to a cataclysm at the onset of Younger Dryas, PNAS, Published online before print July 22, 2013, DOI: 10.1073/pnas.1303924110

Abstract
One explanation of the abrupt cooling episode known as the Younger Dryas (YD) is a cosmic impact or airburst at the YD boundary (YDB) that triggered cooling and resulted in other calamities, including the disappearance of the Clovis culture and the extinction of many large mammal species. We tested the YDB impact hypothesis by analyzing ice samples from the Greenland Ice Sheet Project 2 (GISP2) ice core across the Bølling-Allerød/YD boundary for major and trace elements. We found a large Pt anomaly at the YDB, not accompanied by a prominent Ir anomaly, with the Pt/Ir ratios at the Pt peak exceeding those in known terrestrial and extraterrestrial materials. Whereas the highly fractionated Pt/Ir ratio rules out mantle or chondritic sources of the Pt anomaly, it does not allow positive identification of the source. Circumstantial evidence such as very high, superchondritic Pt/Al ratios associated with the Pt anomaly and its timing, different from other major events recorded on the GISP2 ice core such as well-understood sulfate spikes caused by volcanic activity and the ammonium and nitrate spike due to the biomass destruction, hints for an extraterrestrial source of Pt. Such a source could have been a highly differentiated object like an Ir-poor iron meteorite that is unlikely to result in an airburst or trigger wide wildfires proposed by the YDB impact hypothesis.

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Pediopal
1.5 / 5 (13) Aug 06, 2013
The Clovis people did not "disappear" from the archaeological record! Good Grief!!
Clovis is a type of knapped artifact…a style of projectile point. The people changed styles of projectile points. Kind of like we no longer use brooms as much, now that we have vacuum cleaners.

I suppose the next study will show that the Anasazi "disappeared" from the archaeological record too. For those of you that already think that…they have not they just quietly continued on as the Puebloean people.
cantdrive85
1.2 / 5 (19) Aug 06, 2013
The research lends support to recent claims that a sedimentary layer containing iridium grains and glass-like carbon with nanodiamonds, found at many northern hemisphere sites around the Younger Dryas boundary, is evidence of a meteor impact.


Where is the impact crater? Seems it would be rather obvious if one saw it. Obvious like Barringer Crater at least to explain "iridium grains and glass-like carbon with nanodiamonds, found at many northern hemisphere sites". Does an air burst impact create enough heat to cause nanodiamonds?

Oddly enough, plasma (electric) discharge can cause iridium and nanomaterials. And in another strange coincidence ancient cultures all over the world reported/recorded atmospheric plasma discharge in rock art.
http://www.plasma...S-06.pdf
RealScience
5 / 5 (5) Aug 06, 2013
@cantdrive85 - The rock-art that your link compares to a Z-pinch looks much more like a male human figure than it looks like the Z-pinch - two arms and two legs, even five fingers on each hand.

cantdrive85
1.2 / 5 (17) Aug 07, 2013
Peratt and others have cataloged 4 million "filamental MHD instability" objects worldwide, all oriented similarly to the south.
Here is a full page of examples presented by Peratt.
http://www.plasma...rth.html

4 million is slightly more than chance coincidence!
barakn
5 / 5 (3) Aug 07, 2013
Oddly enough, plasma (electric) discharge can cause iridium and nanomaterials. cantdrive85

Oh, really? Do tell. Does the discharge transmute some other element into iridium or does it create it ex nihilo? Can you provide a reference for this fantastic claim?
cantdrive85
1 / 5 (14) Aug 07, 2013
Edit;
Oddly enough, plasma (electric) discharge can cause [the dipersal of] iridium and [create] nanomaterials.

Sorry, it's past my bedtime. Sometimes words get omitted due to even slower typing than usual.
barakn
5 / 5 (4) Aug 07, 2013
So you still can't explain where the otherwise extremely rare iridium comes from.
RealScience
5 / 5 (5) Aug 07, 2013
@cantdrive85 - I looked at a dozen or so of the links over my morning coffee, and I didn't see anything that would convince anyone who wasn't already convinced.

Right now it is just a collection of drawings, most of which resemble common life forms more strongly than they resemble Z-pinches or other discharges.

As for the more abstract figures, Peratt would have to find a way of dating of the sites to show that they were all done at the same time rather than apparently being spread across the neolithic and bronze ages. Then he'd at least have a mystery that his solution might fit.
cantdrive85
1.3 / 5 (14) Aug 07, 2013
This is probably the most complete paper;
http://www.plasma...3clr.pdf

The idea that these seemingly disparate cultures worldwide would record the exact same figures (adjusted for their field of view) in and around the same time with the same southerly orientation without a common cause seems remarkable to me. There is no possible explanation this is just a coincidence. This is also a great opportunity to use critical thinking and apply knowledge passed to us via our ancestors, whether it be legend, myth, religion, or any other historical bit of evidence such as this to attempt to reconstruct a more accurate representation of human history. By and large, modern science completely discounts any and all reported ancient historical data and evidence, the reaction to Velikovsky's 'Worlds in Collision' is testament to that. The standard theorists don't have any answers for the reported history, as such they choose to ignore asking hard questions.
nkalanaga
5 / 5 (5) Aug 07, 2013
There wouldn't be an impact crater if the object was a "rubble pile" asteroid or a comet, and entered on a grazing trajectory. It would break up on the first pass, slow enough to be captured, and the debris reenter and disintegrate on the other side of the Earth. The same total energy released, but it would be mostly heat and dust, no crater-forming impacts.

There was an article on Phys.org a while back on just that scenario.
http://phys.org/n...ing.html
RealScience
4.2 / 5 (5) Aug 07, 2013
@cantdrive85 - I am a proponent of looking at myths and legends (although not always literally) to see what knowledge can be extracted. But even so I do not find the images presented in the Peratt article convincing.
The wide dispersal of the 'man with two dots' images argues against them being some planetary phenomenon such as an auroral because it would be highly unlikely for a locally-visible phenomenon to decay into such similar patterns in different locals, and yet the patterns are not close enough to identical to be different views of the same root image.
(And Peratt admits that these are 'rarer' images extracted from a larger set of squatter images, so even the cherry-picked data is not convincing.)
A much more likely answer is that something that was present at each site was the model.
In this case that would be a human, sometimes identifiably male.
cantdrive85
1 / 5 (11) Aug 07, 2013
because it would be highly unlikely for a locally-visible phenomenon to decay into such similar patterns in different locals, and yet the patterns are not close enough to identical to be different views of the same root image.

Peratt used supercomputers at LANL to confirm just that, that is to confirm the apparent shape of the object from it's respective location. Also, the idea that at 4+million locations around the earth, during the same era, men chose to carve stickman figures with dots on exclusively southern exposures with no common origin strains credulity in the least. In addition to the rock art, there are many more examples of more modern, yet still archaic to us, "archetypes" common worldwide from many disparate cultures that can only be explained by similar events.
http://penn.museu...ratt.pdf
http://mythopedia.info/
antialias_physorg
5 / 5 (5) Aug 07, 2013
that the eruption of the Laacher See volcano caused a volcanic winter in the northern hemisphere, is also lacking.

Hope so. That's practically next door for me.

Where is the impact crater?

Read the article. Stop at the word "airburst". Look up what that means.
cantdrive85
1 / 5 (10) Aug 07, 2013
Where is the impact crater?

Read the article. Stop at the word "airburst". Look up what that means.

I did, all the way to the last sentence that says; "Petaev and his colleagues caution that future researchers must locate an impact site in order to confirm this hypothesis.".
This article is about an alternative to the airburst, even still I doubt such an event would create nanodiamonds. I'm not aware of a single impact/airburst experiment that produced such a thing, nano materials are widely known to be created by plasma arc discharge though.
RealScience
5 / 5 (4) Aug 07, 2013
... the idea that at 4+million locations around the earth, during the same era, men chose to carve stickman figures with dots on exclusively southern exposures with no common origin strains credulity in the least.


@cantdrive85 - Stick men with dots on the sides have NOT been found at 4 million locations. Peratt has put most petroglyphs into 84 categories, totaling ~4 million petroglyphs at perhaps a few hundred locations. However many of these match humans or other animals, and Peratt claims that these, too are discharge figures, reducing his credibility.

The idea that without a common origin hundred of groups would choose to document an event the same way strains credulity, so petroglyph styles probably predate the dispersal of humans across the continents.

As for the glyphs being contemporaneous, that's what Peratt would have to demonstrate for me to find the geometric petroglyphs at all convincing: nNone before some time, many at that time, few or none thereafter.
cantdrive85
1 / 5 (12) Aug 07, 2013
Stick men with dots on the sides have NOT been found at 4 million locations.

Of course, I was lumping the 84 categories to make the point "with brevity". They state, "If we exclude from consideration those petroglyphs which seem clearly to represent recognizable phenomena (animals, plants, etc.) and focus exclusively on those enigmatic abstract shapes that few comfortably interpret, we find ourselves presented with 84 types of abstract images."
Your claims are directly counter to this statement I cut and paste from above linked article.

The idea that without a common origin hundred of groups would choose to document an event the same way strains credulity,

So, if you place a bicycle in front of an Norseman and he drew the bicycle, you'd expect a different result if it was then placed in front of a Moroccan, or an Aborigine?

cantdrive85
1 / 5 (11) Aug 07, 2013
As for the glyphs being contemporaneous, that's what Peratt would have to demonstrate for me to find the geometric petroglyphs at all convincing: nNone before some time, many at that time, few or none thereafter.

Here is an example of rock art that predates what we are discussing, by at least 8,000 to 15,000 years.
http://phys.org/n...art.html

The people who created this art were realists, they portray minute details that almost renders the image with movement. And there are no stickmen on the cave walls.

This from one of the articles linked above;
"So, could these enigmatic petroglyphs be evidence that humans witnessed intense auroral storms in the past? We believe this is the case and have reason to postulate three episodes of auroral activity of this type, accompanied by rock art carving, which occurred between roughly 10,000 and 3,000 BCE."

The data doesn't conform to your continental human dispersal model.
cantdrive85
1 / 5 (10) Aug 08, 2013
I will say, if we were to observe such an event, the most likely result would be us carving crude figures into stone trying to warn future generations. Modern society as we know it would cease to exist for some time to come.
RealScience
5 / 5 (3) Aug 08, 2013
So, if you place a bicycle in front of an Norseman and he drew the bicycle, you'd expect a different result if it was then placed in front of a Moroccan, or an Aborigine?


No, I mean that if I showed a Norseman an Aborigine and a Moroccan each a bicycle, I wouldn't expect each of them to go a rock face and peck out a picture, unless illustrating on rock had a common origin (whether a shared heritage or something internal to the human brain).
And if illustrating on rock has a common origin, so too could the style and motifs used. And these styles and motifs could differ from the formal style used in the cave paintings, just as doodles and graffiti have styles that differ from renaissance masterpieces.

I'm not saying that mega-auroras aren't illustrated in petroglyphs - an apparent supernova shows in several, so astronomy does figure in - just that I don't find the evidence presented so far convincing.
cantdrive85
1 / 5 (12) Aug 08, 2013
No, I mean that if I showed a Norseman an Aborigine and a Moroccan each a bicycle, I wouldn't expect each of them to go a rock face and peck out a picture

If this type of event did occur, chances are folks would have "headed for the hills". It would be a rather profound event, one that would incur a reaction among some, possibly to disseminate this info to the nearest media outlet. To my knowledge, this preceded twitter and iPads, the nearest media outlet may have been the rock they were hiding behind.

RealScience
5 / 5 (3) Aug 08, 2013
@cantdrive85 - when you say 'possibly' and 'may have' in broad terms you are on pretty safe ground - it is when you unambiguously state "ancient cultures all over the world reported/recorded atmospheric plasma discharge in rock art" that you open yourself to challenges.

With million of petroglyphs, I'd be very surprised if at least a few didn't record astronomical phenomena (and as stated earlier, apparent supernovae have already been documented). If I were Peratt I'd look for total solar eclipses, as these are impressive events that can be determined retroactively thousands of years back and could show up in petroglyphs over quite predictable areas (with the exact areas also giving information on changes in the earth's rotation rate). These could provide information on how 'astronomical' the petroglyphs are, as well as timing (which petroglyphs they are etched over and which are on top of them).
cantdrive85
1 / 5 (12) Aug 08, 2013
it is when you unambiguously state "ancient cultures all over the world reported/recorded atmospheric plasma discharge in rock art"


As with any science one must remain with typical scientific skepticism, however, with such a large data set that is mutually supportive it definitely gives additional credence to the theory. The fact that there are 84 distinct glyphs that represent plasma formations is additionally supportive, if it were a handful I would agree with your comment, but 84 specific examples? Another piece of supportive data is the negative data, glyphs too far north in the northern hemisphere and other areas without a southerly view do not depict these particular shapes, these 84 odd shaped glyphs can only be found where there was a clear view of the southern sky. Keep in mind, there remain 84 peculiar shapes after the obvious shapes were removed. There are many concepts in science that are accepted as "facts" with far less corroborative evidence.
RealScience
4 / 5 (4) Aug 08, 2013
"The fact that there are 84 distinct glyphs that represent plasma formations" is going too far again. A proponent of the theory has identified 84 glyph classes that could represent plasma formation, but some are even more similar to people and other common animals.

The obvious shapes were not removed - the human male shapes are pretty obvious.
Note that they could still be representations of discharges - a discharge that looked somewhat like a human male could be drawn as more human (just as human have with constellations), but figures with plausible alternative explanations should be excluded from the primary evidence.

I do like the geographic view-to-the-south data; if that were supported with solid temporal data it could become a strong case. And if astronomical examples from verifiable events such as eclipses were found as support, it is possible that a case capable of convincing the mainstream could be made.

But what has been presented seen so far is far from that level.
cantdrive85
1 / 5 (11) Aug 08, 2013
Once again, you are misinterpreting the authors, as they state;
"If we exclude from consideration those petroglyphs which seem clearly to represent recognizable phenomena (animals, plants, etc) and focus exclusively on those enigmatic abstract shapes that few comfortably interpret, we find ourselves presented with 84 types of abstract images."
After removing the obvious, they still have 84 abstract shapes which remain to be explained. They may have included some human shapes, such as those with the two peculiar dots below the arms. Those dots represent uniqueness, my five year old draws many stickmen, never has he placed dots in a similar way. Feel free to discount human figures without odd additions as that, but it is unlikely that two or more disparate individuals would carve such an image without a similar origin. The idea such anomalies were "passed down" from previous common gens is also a stretch. Aboriginal migration occurred tens of thousands of years ago, yet conform with data
cantdrive85
1 / 5 (11) Aug 08, 2013
As a matter of fact, many of the plasma instabilities claimed to be the common link of these glyphs are called "Peratt instabilities" due to the fact he is largely responsible for the original research into these plasma phenomena. If anyone were to recognized the morphology of the instabilities involved it very likely would be the man they were named after.
As far as temporal data, it seems as if each individual event is mutually supportive for that events data set. As such, he is able to identify three major events over the 7000 year time frame.

This one may need translation, unless you're fluent in Chrome like I am...;
http://www.rupest...ras.html
RealScience
5 / 5 (2) Aug 08, 2013
Regardless of what the authors say, they included petroglyphs of upright figures with two arms and two legs, five fingers on each hand, and male genitalia.
Those figures also had a dot or a circle on each side of the figure, but that does not change them from being recognizably human - in spite of the two dots, those figures look far more human than they look like the plasma discharge example they were said to resemble.
As I said before, Peratts case would be stronger if he made the case based on other glyphs and only included those at the end as examples of possibly anthropomorphized instabilities.
As
cantdrive85
1 / 5 (10) Aug 09, 2013
I believe the two dots are too profound to ignore when comparing the glyphs to the discharge, and only some of the glyphs have fingers et al. Anyway, let's get a bit philosophical. Peratt surmises a solar wind event 1-2 orders of magnitude stronger than we currently experience. I tend to lean toward Velikovsky's POV, that of celestial near misses. Either scenario would produce "super-aurora" as well as other possibly destructive/harmful effects. A solar wind event would surely dump a tremendous amount of energy to not only the poles, but the atmosphere and planet as a whole. Severe/unusual weather, earthquakes, and other negative effects of excess solar radiation and such.
In a near collision, the planetary plasma sheaths would transfer tremendous energy between the two bodies causing chaos and destruction.

In either case, a radiant "human-like" figure positioned above the pole while hell breaks loose around these people may invoke myths and legends of when the "gods" came to earth.
Gmr
1.9 / 5 (9) Aug 09, 2013
Wow - Velikovsky - haven't heard that name in a while. Not since Carl Sagan made fun of his bizarre ideas back in the late seventies.

Talk about old school.

Anyway, I'm intrigued by this as if platinum/aluminum and platinum/iridium ratios can be shown to indicated asteroid impacts, if there aren't more to find. They were looking at that boundary, is there any other data that might corroborate or refute that? Should we be combing ice and sedimentary cores for impact signatures to see if we can match up a record of these with minor or major extinction events?
cantdrive85
1 / 5 (10) Aug 09, 2013
Wow - Velikovsky - haven't heard that name in a while. Not since Carl Sagan made fun of his bizarre ideas back in the late seventies.

Yep, the inquisitors were complete and thorough in their admonition of Velikovsky, whether or not they read his work (most didn't). Einstein was apparently convinced though.
http://www.thunde...host.htm
barakn
not rated yet Aug 09, 2013
Jeez, what isn't covered in this vast repository of knowledge: http://www.thunde...host.htm
cantdrive85
1 / 5 (11) Aug 09, 2013
That's what "cosmology" is, a theory of everything so to speak:

"There is a new cosmology poised for recognition. The Electric Universe is inspiring people of all ages. It is easy to understand. It is an expansive and inclusive science that motivates 'garage tinkerers' to perform their own experiments. It merges science and the humanities at a deep level. Those who know it say, "It just makes sense." For the first time we begin to understand our existence on this fragile blue planet and our connection to the Sun and the amazing universe.
Even at this early stage in its development, the Electric Universe has been successfully predicting and explaining surprising discoveries. It is unique in the space age in that it grew from forensic investigation of the earliest astronomical references. It did not assume that the sky has always appeared like today or that the orbits of the planets can be simply retro-calculated into prehistory... (con't)
cantdrive85
1 / 5 (12) Aug 09, 2013
"...The research culminated in the identification of weird prehistoric petroglyphs as faithful recordings of mighty electrical discharges in prehistoric skies. When combined with modern plasma science and recent discoveries from space probes it was evident that electricity plays a key role in celestial dynamics. This raised the issue of the electrical nature of the central body in the solar system — the Sun.

There is practically no scientific or cultural activity that is untouched by the Electric Universe, which is the hallmark of a real cosmology. The Electric Universe is based on real-world experiment and observation and not on oxymoronic 'thought experiments' or unfettered speculation about what might be going on unseen inside a star or in deep space. It shows more clearly what remains to be discovered and the preferred directions for future study and exploration." Wal Thornhill
http://www.holosc...g-point/
Gmr
3 / 5 (14) Aug 10, 2013
The Electric Universe is inspiring people of all ages.


To what? Facepalm en-masse?
Lurker2358
1 / 5 (6) Aug 10, 2013
I don't see why impacts wouldn't/couldn't create nano-diamonds. The amount of energy released in these events is huge, and the pressure, i.e. shocking the soils and bedrock.

The Tunguska event was large enough that it caused some atmospheric disturbances even up wind, but that was nothing compared to an alleged object capable of making a 1000year drop in temperature. Coincidentally, 13000-1000 = 12,000 years ago, which is the same age as Gobekli Tepe, which records many animals in statues which no longer live in the region...indicative of massive climate change since then.

If it was an airburst, finding a "crater" might not be possible, especially if it happened over water. If it happened over land, you'd need to find something like a massive tree blow-down that got buried somehow, which is unlikely since this debris might have been swept away by local glaciation during the 1000 year cooling period.

Finding the "crater" from an airburst 13,000 years ago seems a daunting task.
Lurker2358
1 / 5 (6) Aug 10, 2013
I don't think it's just about isotopic ratios of heavy metals, though the platinum data was brilliant, because a 100 times increase is clearly evidence that something dramatic happened involving rock.

But consider, large airbursts like Tunguska produce a nuclear explosion, it's not just about kinetic energy. The recent one in Russia was not large enough to produce this effect.

If the event had happened recently, you'd expect to find high levels of heavy hydrogen and helium in the environment, though these would't stick around for long, because they'd get blown away by the wind or the rain, unless they were embedded in something, such as, vitrified sand, or perhaps tree trunks, maybe the ice core record. Otherwise, I think it would just get diluted to a level you wouldn't be able to detect. You could check the ice cores for Carbon 13, which might be present in Chondrites. An object formed in a collision could have characteristics of both chondrites and metallic bodies.