Zero expertise in any of the related disciplines to interpret or judge any of this, but I can say with confidence that the related Wikipedia page https://en.wikipedia.org/wiki/Younger_Dryas_impact_hypothesi... is a wild read and outright flamethrower at everything about Younger Dryas and seemingly, everyone involved.
For those that don't have the context ...
The Younger Dryas theory supporters is controversial across multiple disciplines because it challenges the idea that human progress has always been linear (gets better over time).
Some believe that ~13,000 years ago, humans were highly advanced, but a massive flood (Younger Dryas) wiped out & reset civilization.
Supporters of this theory often point to two things: nearly all major religions reference a great flood, and there’s a current lack of understanding how ancient megalithic sites were built with tools thought to be available at the time (primitive bronze tools, etc).
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Unfortunately, it seems like folks from both sides of the topic talk-past each other ... and at least I haven't seen a balanced debate on the subject. If someone has seen a balanced assessment, please share.
> Some believe that ~13,000 years ago, humans were highly advanced, but a massive flood (Younger Dryas) wiped out & reset civilization.
What kind of "highly advanced"? Iron-age equivalent, industrial revolution, sci-fi with antigravity, ...?
Depending on who you ask, it can be anything on your list. You can expect such claims (of an advanced ancient civilization) to be highly speculative and probably supporting their version of the history. And it's proposed by everyone from young earth creationists to alien colonization theorists.
A flood? I thought it was at least an impact winter or something. The linked wiki article agrees. A global flood is truly unfeasible.
I can't speak anything about the scientific validity of the theories. But it's true that many modern religions have similar stories about a flood catastrophe. But has anybody considered that this may be because many of the biggest religions today originated at the same place?
Flood myths are much more common than that. But the easy reason is that floods are extremely common, and flood plains are among the best places to build a city.
The Younger Dryas debate spans climatology, archaeology, geology, and astrophysics, creating tension across multiple disciplines.
There is scientific evidence that the Younger Dryas event occurred, however, no universally accepted scientific study that conclusively proves WHAT caused it.
The Younger Dryas was not an ”event”, it was a period in Earth's geologic history that occurred circa 12,900 to 11,700 years Before Present (BP).
Kind of pedantic?
I think everyone knows the debate is around the 'event', which caused a 'period' of geologic history which is referred to as "Younger Dryas". I guess once the 'event' is known, it can be named something, like "The Younger Dryas Event".
What I'd like to know, is why just one event. There is this paper, and also the crater found in Greenland a couple years ago. Maybe there was a more general bombardment, not just a one-off smoking gone.
There are several papers arguing that there is no "one event" a la https://www.sciencedirect.com/science/article/pii/S001282522... and others.
The crater in Greenland has been dated to about 60 million years ago
There doesnt have to be an event.
The current accepted theory is (from the gps wiki article)
"is an alternative to the long-standing and widely accepted explanation that the Younger Dryas was caused by a significant reduction in, or shutdown of the North Atlantic Conveyor due to a sudden influx of freshwater from Lake Agassiz and deglaciation in North America."
I'm not sure what definition of "event" you are using. What you quoted is an event. Really anything that shows up as a spike in a chart on ANY timescale, is an "event." The word has broad meaning in the sciences.
The person I am replying to is using event in the terms of "Something that caused" not "Thing that happened" and then goes on to further assume more airbursting asteroids.
Yes a thing happened. But theres no need for a smoking space gun.
I literally said "why just one event".
I don't know if it was asteroid or not, that is why there is controversy.
How is "sudden influx of freshwater from Lake Agassiz and deglaciation in North America" not an event?
As to the derision on asteroids, not sure why, considering we find evidence of them everywhere. Why not consider it as an option.
Sorry if my memory is like everyone else's. When the Greenland Crater was found, there were 100's of articles linking it to Younger Dryas. It was dated later and discounted as being too old, that did NOT get 100's of articles, so was not widely known. I didn't realize it till this exchange.
The ”event” you mention might sound like it happened instantly or at least within a day or two, but it likely took many hundreds of years. So, not an ”event” in the sense an asteroid impact is an ”event”.
”Process” or ”period” would make more sense when things are happening at those time scales.
100 years out of 10,000, is it an event?
I understand the point.
Just have had enough conversations with engineers about "is a micro second fast enough", "nothing is really happening, a whole second is plenty".
Time scales can make a lot of things look long or instant.
Everything depends on context, yes. But in the geohistorical context, ”events” are commonly understood as asteroid impacts, such as the Tunguska event and the Triassic–Jurassic extinction event, so the choice of word carries a heavy implication in this context.
Isn't part of the issue in this discussion, and maybe the controversy. Is that the knock on effects can take decades/100s of years to develop. An asteroid is 1 day, but the fallout and seasons changing can take years.
So by the time you look in geologic record, it is 10-100 of years of 'evidence'. And finding a single point event is difficult.Yes, it can take hundreds to thousands of years or more for the impulse of cosmic event to reach a new steady state in global climate. The KT extinction wasn’t “fast” either.
Is the 0 point for Before Present a different year than the Jesus year? I've never heard it used before.
It's actually 1950 https://en.m.wikipedia.org/wiki/Before_Present?hl=en-US
That's right around the time the "modern" era ended and "post-modern" began. Funny we've been making these errors since basically the beginning of time. Looking at you, New Bridge, the oldest bridge in Paris!
Ish. It's technically correct for BP and radioisotope dating specifically, but other dating methods don't use the same scale like TL. You'll commonly see kiloanni (ka) used instead and that may or may not be referenced to 1950 depending on the whims of the author.
Thank you!
It’s approximately 370 to 408 billion seconds before the Unix epoch.
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There’s a lot more dogma on Wikipedia than academics would like you to believe
There is a lot of dogma in academia too!!
How is this supposed to work with the sedimentation? The glass spherules under the lake are maxxing out 5-6 meters below the surface. Where does the material on top of that come from, and why didn't it fill in the lake, but leave it intact & with ridges?
Second, if you think of an impact at an angle, the crater and its ridges form an ellipse. If its coming very flat, the structures might look rather parabolic, but still bent inwards. In the article, the north ridge is bent outwards. How? Questions over questions.
Interesting. There’s a hypothesis that Earth was struck by an impact 12,800 years ago in North America but the impact site wasn’t identified
https://en.m.wikipedia.org/wiki/Younger_Dryas_impact_hypothe...
Could these be related?
The evidence for multiple strikes around 12,800BP has been piling up for quite a few years now. There are other theories of course. A few papers :
Alaska - https://dx.doi.org/10.1086/695703
South Carolina - www.nature.com/articles/s41598-019-51552-8 (plus Article: https://theconversation.com/new-evidence-that-an-extraterres... )
Chile - https://www.nature.com/articles/s41598-018-38089-y
South Africa - https://dx.doi.org/10.1016/j.quascirev.2014.06.017
Syria - https://dx.doi.org/10.1038/s41598-020-60867-w
California, Channel Islands - https://dx.doi.org/10.1016/j.quascirev.2008.09.006
If you actually click on the link, it mentions this both in the abstract, and a detailed comparison of evidence in a whole table.
I hadn't heard of this, but it says:
>The hypothesis is widely rejected by relevant experts.[2][1][3][4] It is influenced by creationism [...] It is an alternative to the long-standing and widely accepted explanation that the Younger Dryas was caused by a significant reduction in, or shutdown of the North Atlantic Conveyor due to a sudden influx of freshwater from Lake Agassiz and deglaciation in North America. [...] Authors have not yet responded to requests for clarification and have never made their raw data available
Is there a reason why the widely accepted explanation isn't satisfactory?
The publication of this research.
One possibility discussed in the publication is that the sudden influx of freshwater from Lake Agassiz was caused by the Perkins Louisiana impact.
It happened at the end of an ice age, when mile-thick glaciers were melting away. That’s a lot of fresh water going to the oceans.
The argument is that the impact event(s) are WHY the ice age ended.
Ohhh… cool!
… and widely criticized as a creationist theory.
Which has nothing to do with the legitimate scientific question of whether an impact triggered the interglacial warming period we're currently in.
The point is that it is not a legitimate scientific question, as those posing it are disregarding all evidence for geological and cosmological causes for rapid deglaciation.
The YD impact hypothesis is motivated by creationist thinking (hyperbolically ”god threw a stone at us to relieve mankind of ice”) and the idea has been thoroughly refuted.
Clinging to beliefs when there is ample evidence to the contrary is the very opposite of the scientific method.
The original paper proposing a YD impact was serious science put forward by serious academics, AFAIK: https://pmc.ncbi.nlm.nih.gov/articles/PMC1994902/
That it was later a cause taken up by creationists is annoying, but it has no bearing on the scientific question (which is as yet unsettled).
Look a lot of this passes the sniff test but anything Younger Dryas related I have to assume based on past performance is all buillshit designed to prop up religious fundamentalists and bodgy history.
???
There's no link to anything religion wise with the Younger Dryas AFAIK.
My only experience studying it has come from the geological / astrophysics sides though.
Comet Research Group is funded by fundies. They sort of angle towards science when making claims, but those claims are sort of designed to support a scientific creationism angle if they ever get upheld.
It has apparently been taken up as a cause by creationists.
Yeah. It’s conflation of coincidence (as in coincide) with causality, as usual. That there was a widespread major flooding event doesn’t support the existence of a God, though (unsurprisingly) most human cultures have a distant memory of such an event. It’s a similar assertion to saying that the existence of humanity is proof of a creator.
I don't know about the sniff test. The paper here does a little bit of the amateur scientist thing where they belabor details that real experts tend to take for granted. That doesn't make it wrong, but it increases the skepticism warranted.
I do agree the religious link is weird. The mere presence of a 12800 year timeline contradicts YEC. Then again, that kind of logic doesn't always stop pseudoscience people, especially the more conspiracy-flavored ones.
Also, the narrative of the paper references the lead author's dad telling him a story as a child based on not-uncommon geological features, alone. Either this is some amazing coincidence or self-confirmation bias on the part of the authors.
I would have liked to see 10 digs in a similar geological region thats not being claimed to have been airbursted as a control.
Not sure that's necessary. Shocked quartz is distinctive, and strongly diagnostic of either cosmic impact or nuclear detonation; I think you can safely think of this as the required control digs having been done decades ago. It's either there or not. If it's there, that place had an impact. We just need some unbiased people to go check the physical facts.
>The mere presence of a 12800 year timeline contradicts YEC
There are other creationists working on the timescale issue, attacking dating methods etc.
TBH if someone provided evidence of a flood, they would probably just publish bs suggesting the timescale is wrong and push out a bunch of YEC textbooks stating it as evidence of the biblical flood.
So you're going to ignore the possibility of events that happened thousands of years before the young earth creationists say the Earth was even formed because of a possibility of association with young earth creationists?
I am going to be even more skeptical in places where people being intentionally misleading often post their falsehoods yes.
Is it plausible for such a large airburst as hypothesized to leave behind such a small crater?
I'm guessing that like everything south of a certain point in Louisiana, it'll start out as a larger landscape feature and then gets filled in by sediment.
Oh, and before I forget: the kudzu will probably eat what's left of the crater.
Yes. If it exploded in the air, then there is no crater.
Indeed, cf. Tunguska event ([1]) from 1908.
Huh? There’s definitely a visible impact structure: https://www.google.com/maps/@60.9045428,101.9279614,14z/data...
Zoom out a bit and it looks pretty unremarkable for the area.
One has to be careful interpreting craters in areas with permafrost. https://www.bbc.com/future/article/20201130-climate-change-t...
Buried the lede:
"Son claims Dad was right all along"
Sounds like we finally have some proper dates for the Finno-Korean hyperwar.
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Drunk? New user, huge burst of random comments, none of which make sense?
You okay, buddy?
I suspect someone's testing their LLM-based HN-commenting script.
They need a lot more training. Those comments are something from the ol' Fark or slashdot era. Waiting for the LLMs with posts like "First!"
Maybe, but we've been getting BS like this from before LLMs. Some people really are just that crazy.