Alternative Theories? As for me, I think there could be a third alternative, such as some type of true “nuclear winter” as a result of some sort of war that a preexisting civilization might have suffered.
Mystery of The Younger Dryas
As historical mysteries go, this is one of the bigger and stranger ones. Scientists have tried to unravel the odd events of the Younger Dryas period for years. Even now, researchers are in an ongoing struggle to find the cause or causes of the event, and are still struggling to do so, even as this article is being written.
What was this Younger Dryas conundrum all about? Well, an event took place near the close of the last glacial age, when the Earth was finally warming and the glaciers in North America and Eurasia were in full and rapid retreat, and had been for millennia by that point in time. Then, suddenly and dramatically, around 12,800 years ago, the inexplicable happened. The weather abruptly reversed its warming trend and a little ice age, now known as the Younger Dryas ensued. Temperatures plummeted. The equivalent of a “nuclear winter” set in. Glaciers began to advance once more and the Earth became cold!
Also at about this time, the major megafauna of North America began to go extinct. This was a major extinction and widespread across a large number of species, including the wooly mammoth, giant sloth, saber-toothed cats, types of bison, massive bears, etc. Then, too, an indigenous race, known as the Clovis People, seem to have vanished from North America right at that time. They had occupied some areas of the continent prior to the Younger Dryas for thousands of years.
There also seems to have been a large number of fires that occurred in tandem with all of this, perhaps even a continent wide, or “crown fire,” although some researchers dispute this last. Moreover, whatever caused this event, it seems that it was mostly centered on the North American continent, although Eurasia suffered from the cold conditions, as well, even as did other parts of the Earth. The Younger Dryas was not a pleasant time to have endured anywhere on the globe.
This sudden chilling of the planet was without explanation for a long time. To this day, there is still no completely satisfactory answer, at least, not one with sufficient evidence to proclaim it as the most probable and correct cause. Even so, there are some major theories and these are based on the following facts:
- The Younger Dryas did happen. We know this for certain and so it constitutes an irrefutable fact. We know without a doubt the Earth suffered a sudden and rapid cooling. An abrupt and extreme chilling of the planet occurred, and it continued for about 1,200 years. At its coldest, the conditions were almost identical to that of the height of the earlier glacial period. The Younger Dryas event was truly a mini Ice Age.
- During this period there were (as mentioned above) mass extinctions of the megafauna that inhabited much of North America. The Clovis People also seem to have vanished.
- There is evidence of major fires, especially on the North American continent.
- At the end of the Younger Dryas, suddenly and abruptly, climate conditions once again reversed. This time, the average temperatures for regions around the planet went up, and they went up quickly. Warming and melting of ice occurred. Glaciers quickly retreated once more. This resulted in the release of their fresh water, once locked up as ice. This additional water raised sea levels worldwide and flooded low-lying areas, which are still flooded to this day. Again, all this happened very quickly.
- Although we now have evidence there was probably some agriculture around 13,000 years ago (beer making is supposed to have been taking place in the Middle East at that time), civilization didn’t really seem to kick off until the end of the Younger Dryas, at least, civilization as we now think of it today with a lot of agriculture to sustain it, cities, commerce, etc. I am not at this time referencing what may have been major megalithic world cultures, which we now seem to have some real evidence for, as well.
- Now, given these facts, scientists, as mentioned above, have struggled to find the cause of this strange chilling of the planet when by all known indicators, the Earth should have continued with its warming trend. Although many theories have been advanced, including the idea of a nuclear winter being caused by a super volcano erupting (no real evidence to support this idea has been found), there are two theories that seem to be most probable as a cause of the Younger Dryas, at least, according to scientists.
The Great Floods. The first theory and one that many think is still correct, is that of a flooding event, where a great deal of water, fresh water, was swiftly released into the Atlantic Ocean. This, according to the theory’s proponents, resulted in disrupting the gulf stream flow of warm water, and thus interrupting the “conveyor belt” of ocean currents that allowed warmer waters to move to colder regions and vice versa. The result? The northern hemisphere suffered a mini ice age, the Younger Dryas, until the ocean thermal conveyor belt again came into effect.
This theory has a lot of merit. If there had been a large body of glacial melt in the form of a vast lake, for instance, one that was damned by a portion of the retreating glacier(s), and then was suddenly released all at once, this could be a cause of the Younger Dryas. The fresh water so precipitously freed, would quickly make its way to the ocean and thus reduce the ocean’s salinity in that region. This means the ocean’s salt-induced density levels would change with such a massive dilution, and this in turn could have shut off the ocean’s current thermal conveyor belt.
Support for this theory comes in the form of such flooding events that we know for sure did actually take place. One of these was the Missoula Floods, for the glacial Lake Missoula. Also known variously as the Spokane or Bretz Floods, these catastrophic deluges repeatedly devastated portions of Washington State, and adjacent regions.
Blocked in by a huge ice dam, the lake repeatedly collected meltwater. This would rise to the point where the ice dams that held the lake back eventually failed under the pressure, or due to continued melting. Once drained, the ice damn could often return with fluctuations in the climate. Gradually, the lake would fill again behind this wall of ice, until again there would be another catastrophic failure of the ice dam and yet another flood would occur.
Nor is this the only such North American glacial lake to have such vast consequences for the world. There is also Lake Agassiz. As Wikipedia states:
“During the last Ice Age, northern North America was covered by a glacier, which alternately advanced and decayed with variations in the climate. This continental ice sheet formed…between 30,000 and 10,000 years ago. As the ice sheet disintegrated,  its meltwaters created an immense proglacial lake. ”
Again, this was a lake of truly vast proportions. At its peak about 13,000 years ago, Agassiz inundated about 170,000 square miles, was larger than any lake in the world today, and contained a massive amount of fresh water. However, as glacial ages do, the drainage routes of this lake were periodically cut off by the returning ice and so changed. Around 10,000 years ago, even as the ice began to melt and the ice sheets retreated once more to the north, Lake Agassiz had grown to those monstrous proportions. Then, about 8,200 years ago or perhaps a little earlier, the lake found a new way to drain. This time, it was through the Hudson Bay region when the ice there had sufficiently melted to stop being a barrier to the lake’s rising waters.
The lake drained almost completely this time! Water flooded into the Arctic sea, fresh water diluting the saltwater. Again, this would act to shut down the ocean’s current conveyor belt for transporting cold water to warm regions, and warm water to colder regions. The result? A quick chill down of the northern, and to a lesser extent, the southern hemisphere of Earth. This, some scientists argue, brought on the Younger Dryas event.
Now, as with Lake Missoula, Lake Agassiz reformed at different times and found different ways to drain, depending on how its drainage patterns might have been blocked at any particular time. Sometimes, the lake would use the Mississippi drainage basin to empty itself. These different periods and different drainage routes were referred to as “phases” for the lake, and were:
Lockhart Phase—12,875–12,560 years ago;
Moorhead Phase—12,560–11,690 years ago;
Emerson Phase—11,690–10,630 years ago;
Nipigon Phase—10,630–9,160 years ago;
Ojibway Phase—9,160–8,480 years ago; and
Added to these phases were several smaller or partial ones associated with these major ones.
Now on the face of it, one of these flooding events does seem as if it could account for the onset of the Younger Dryas, since any one of the deluges that acted to dilute areas of the ocean with large amounts of fresh water could theoretically have triggered such a mini ice age. However, there are some major problems with this approach.
For one thing, there were at least several such flooding events, if researchers are correct. Why then would there have been only one Younger Dryas period, instead of several of them, or even many such events occurring repeatedly? This does not appear to be the case. There seems to have been only the one major such cool down according to the evidence currently available.
For another thing, we don’t seem to have much in the way of physical evidence for a vast and sudden flooding of the oceans in this way at all. Such a massive release of waters should have caused a marked and long-term change to the terrain over which those waters rushed and flowed.
Other articles by Rob Shelsky
Yet, again, we don’t seem to have much in the way of evidence for this having happened. If water did flow to the sea, it doesn’t seem to have done it quickly enough as to cause major erosion patterns, channeling, or “badlands” as is seen in eastern Washington State from such rapid and massive flooding. In short, we have no real evidence of such a type of flood happening in such a way.
Impact Theory. Because of this, another theory has come to the fore and this one is the Impact Theory of the Younger Dryas. Briefly put, this theory says that an object from space, such as a fragment of a comet, or possibly an asteroid or large meteoroid either impacted the ice sheets in North America, or as with the Tunguska blast, exploded in an air burst higher in the atmosphere. Either way, this could have resulted in continent-wide devastation and the subsequent onset of a chilly period due to a nuclear winter style of cool down.
Some researchers support this idea enthusiastically, since it would so neatly explain all the things we do see with regard to the Younger Dryas. The dust raised by the explosion, the smoke of countless forest fires that would have raged everywhere would have contributed to blocking out the sun’s rays, thus chilling the Earth down once more. The resulting destruction of the habitat would then cause species of larger animals, those most dependent on their current environment to sustain them, to begin to die off, just as an ancient asteroid impact contributed to the extinction of dinosaurs millions of years earlier.
Those same researchers point to evidence of there having been a lot of forest fires around the time the Younger Dryas started, and layers of ash show there were such fires, even as those scientists claim. This, along with the extinction of the larger mammals, the sudden disappearance of the Clovis People, and the chilling of the Earth all happening at the same time lends great credibility to the Impact Theory as the cause of the Younger Dryas period.
All this sounds convincing as evidence of an impact, except for one thing—that is, there is no physical evidence in the form of a crater or significant debris from such an impact to be found anywhere, it seems. However, some researchers claim that tiny “microspherules” have been found, which could have formed as a result of an atmospheric explosion of a comet fragment or asteroid. Such an explosion, as with the Tunguska Blast over Siberia in 1908, would leave little trace in the form of debris, and there would then have been no crater formed, as with the Tunguska event.
Even so, there are problems with this “proof,” as well. Microspherules can be formed in other ways, including by sudden explosive volcanic activity of some type, and at times, they can even form from certain types of pollution.
Furthermore, those opposed to the idea of a comet or asteroid explosion/impact point to the fact that the data for fires occurring at the beginning of the Younger Dryas ignores the fact that ash has been found in other places and from other periods in North American history, as well. Such researchers point out that with a continent-wide forest, large forest fires would have been inevitable and probably often. They say it wouldn’t have taken an extraterrestrial impact to cause them. Something as relatively trivial as a bolt of lightning could have started a massive forest fire.
Those same opponents to the Impact Theory also point out the Clovis People may not have disappeared at all. Archaeologists often base evidence for a type of people on the tools they used. The Clovis People supposedly disappeared because the types of spearheads they made stopped being made and another type of spearhead took their place. Does this mean the Clovis People actually vanished? Some researchers say, no, it does not, that all it means is the Clovis People adopted a different style of spearhead, instead, and went right on living.
As for the large animal extinctions of the Younger Dryas, opponents point out that these were not an isolated event. As one article put it at https://www.sciencenews.org/article/younger-dryas-comet-impact-cold-snap:
“…[T]hose large Ice Age animals such as mammoths, he adds, they were in decline, but their disappearance wasn’t that sudden. “All these animals running around and then, boom, at 12,800 years ago they just go away? That’s just not the case,” Holliday says. “These extinctions were global and happened at different times around the world.””
So the bickering and arguing over the true cause of the Younger Dryas event continues. Always, it seems one side presents what they feel to be evidence and the other side then proceeds to poke holes in that so-called “evidence.” Yet, things do change in the debate, and we do seem to be getting closer to some answers.
Crater Found. For example, even as recently as yesterday, news has come of a crater being discovered, a large one being found under the ice sheet in Greenland. Moreover, it is a big crater! It is estimated an asteroid, meteorite, or cometary fragment measuring about 1.5 kilometers across created the pit! The crater measures some 31 kilometers across. Furthermore, shocked quartz and elements were found that also signify this was an impact crater. In fact, so telltale are the clues found that we can reasonably and safely assume the impactor was not only an asteroid, but a particular type of iron asteroid.
So, did this impact in Greenland bring on the Younger Dryas? Scientists think possibly not, because the timing of the event is too far off to have been the cause of that particular cool down of the Earth. The crater is believed to have been formed at least before 11,700 years ago, and although this puts it reasonably close to the time of the Younger Dryas, it probably couldn’t have been the cause.
However, because the crater is beneath hundreds of feet of ice, precise dating of the impact is not yet possible with the evidence so far retrieved. Even so, scientists say for North America to have been so affected by an impact in Greenland would seem to be unlikely, that in order for an impact to cause the damage it did, the explosion would have to have been somewhere on, or over the North American continent.
Where does all this leave us in our trying to determine the cause of the Younger Dryas? Well, it seems we are rather caught between the proverbial “rock and the hard place.” Two major competing theories, both claiming to have some evidence for them, both reasonable explanations of the Younger Dryas, but neither with enough evidence, seemingly, to make it the ironclad cause.
Alternative Theories? As for me, I think there could be a third alternative, such as some type of true “nuclear winter” as a result of some sort of war that a preexisting civilization might have suffered. The Vedic Texts of India describe just such an event, for example. In other words, we have written records of a planetary war, as well as one taking place in space, if we are to believe the Vedic Texts on the subject. We also have corroborating evidence from the cuneiform writings of the ancient Sumerians, as well, with regard to the Anunnaki.
Now, this isn’t ironclad evidence either, since many claim these are nothing more than myths and legends (but in some cases, as with the Vedic Texts, being highly detailed myths, if so!). Therefore, as to what might have caused the Younger Dryas, is, as mentioned at the outset of this article, still a conundrum, still a mystery.
Was it a natural disaster brought on by flooding of the ocean with fresh water? Alternatively, was it an asteroid, cometary fragment, or massive meteoroid impact? Alternatively, might it have been the death throes of a megalithic civilization that was global in nature?
If I had to choose, I’d be hard-pressed to decide and that’s the simple truth. All these theories could account for the Younger Dryas. However, when we put the Younger Dryas into context with other events of those times, and not just as a standalone happening, one could reasonably argue for the Megalithic civilization idea as being the best one, but that would be the subject of another article.
For now, let’s just say there is insufficient evidence to show us the exact cause of the Younger Dryas, and so we await more evidence to be sure. Until such time, each of us must simply choose the explanation that they feel best serves the available data, and also they have to decide which theory has the most reliable evidence to support it. That seems to be the nature of things when we confront such enigmas as the mystery of the Younger Dryas. I have faith that eventually we will find the answers. Humans are tenacious and when it comes to solving mysteries, we are especially so! Let’s hope this tenacity works for solving the Younger Dryas enigma, as well.
By Rob Shelsky