Ancient Apocalypse archaeology update 7: How apocalyptic was the Younger Dryas?

In his closing arguments for Ancient Apocalypse, Graham Hancock takes us to the channeled scabland of Washington State on the Northwest coast of North America. Here, he tells us, is clear evidence of a catastrophe so gigantic that it could have wiped out an entire advanced civilisation, leaving only a few survivors. As we know from the previous episodes, he believes these survivors went on to provide their advanced knowledge to our early post-glacial ancestors, who rebuilt our society in the course of time.

The Lake Missoula event, from Baker 2009

The channeled scabland, along with many other formations and regions around the world, were carved around the time of the Younger Dryas, a short, sharp cold snap toward the end of the last ice age. I’ve seen and worked on some of those formations in my own fieldwork in the north, including the giant beach-like ripples that stretch across hundreds of meters or more in some places. 

Hancock tells us that geologists and archaeologists refuse to accept that such catastrophic events took place in the past and that they played an important role in human history. Therefore, he claims, we unreasonably reject his theory of an advanced ice age civilisation.

He blames this rejection on the uniformitarian assumptions of mainstream geology and archaeology, according to which, he says, change is gradual. This critique would have made more sense a hundred years ago. It is true that for a long while, geologists thought that change was mostly gradual. 

Hang on to your hats, because here we need to do a little bit of history of science, if we’re going to understand where Hancock gets it wrong. The core idea of uniformitarianism is not that all change is slow and gradual, but rather that the forces we see at work, shaping the landscape around us in the present, also could have shaped it in the past. Early geologists, like Lyell, saw mountain glaciers at work, shaping valleys in the present. These kinds of processes are fairly slow by human standards, and so geologists associated the idea of uniformitarianism with slow change. It need not be.

For example, if we can see catastrophic processes shaping the landscape now, like volcanos, tsunamis, earthquakes, and yes, even cosmic impacts, the uniformitarianism tells us that when we see similar traces in old landscapes, we should first blame them on those catastrophic processes, unless they are inadequate or inconsistent with the evidence.

When they saw similar traces on very old landscapes in which there were currently no glaciers, they suspected that glaciers had done the work, and that they had done it slowly. This was the origin of the idea of ice ages, which has since been demonstrated using many other tools and techniques.

The gradualism that got associated with uniformitarianism also appealed to early modern scientists in general, because it gave evidence against creationist accounts of the origins of the Earth and of life. Divine intervention does things quickly, even suddenly. And then there was light. Whereas, nature, it was thought, does things gradually, and according to known laws that are not mysterious or supernatural, and that we can observe around us all the time if we only look.

Over the course of the 20th century, geologists had to concede that not  all, or even most change in landforms was gradual, and that catastrophic events were sometimes important too. In fact, the story of the scabland played a role in the gradual geological acceptance of catastrophic events as shapers of the Earth and of the environment to which humans constantly adapt.

As Baker (2009) tells it, “The Spokane Flood” hypothesis was first proposed in 1923 by JH Bretz to explain the spectacular features of the scabland. The geological community at the time, which did mostly hold that geological change was gradual, rejected it. However, by the 1960s, the evidence was overwhelming that massive, sudden floods had shaped the region, and the hypothesis was broadly accepted. As we see again and again, scientists look at evidence and change their minds over time.

In fact, there were many such sudden floods caused by the catastrophic draining of pro-glacial lakes around that time. It only makes sense, because as the Earth was warming up at the end of the ice age, so much water was being released from glaciers, all at the same time. The water had been trapped in those glaciers for sixty thousand years, and that water had to find its way to the sea somehow. Some of it went slowly and gradually, but some of it went in these great cataclysmic drainage events.

One of them, the draining of Lake Agassiz in Northeastern North America, has even sometimes been blamed for initiating the Younger Dryas itself. For Lake Agassiz, Norris et al. (2021) estimate a discharge of 21 000 cubic kilometers of water (more than 5 000 cubic miles) over a period of six to nine months. 

That’s a lot of water. It’s a truly biblical quantity. It is so much water, in such a short time, that it could have disrupted global ocean circulation and caused the Younger Dryas cooling event. Now that, is catastrophic change.

By comparison, Baker tells us that the sudden drainage of Lake Missoula that created the scabland was on the order of 2600 cubic kilometers, or about twelve percent of the Lake Agassiz event. To make up for the relatively small size of the Lake Missoula event, Hancock tells us that it could have been created by an asteroid impact, thereby initiating the Younger Dryas. 

It could have been, but if we have events the size of lake Agassiz, we don’t simply don’t need the asteroid to explain the subsequent cooling. And we certainly don’t need the asteroid to explain the draining of Lake Missoula either.

In other words, there were plenty of catastrophes going on toward the end of the last ice age. While asteroids could have been part of the package, they need not have been. Some of these catastrophes were very sudden, such as the drainage of pro-glacial lakes. Some were more extended, like global changes in precipitation patterns, which would have radically affected the plant and animal communities on which humans depended for survival. 

The extinctions of large mammals to which these changes contributed around that time certainly would have been seen as catastrophic by our ancestors, even though they played out over many generations.

Some of the catastrophes were even more sedate in their pace, but their impact was just as great. As Hancock reminds us regularly throughout the series, sea levels went up more than 100 metres at the end of the last ice age. That took several thousand years, but it was something that radically changed where and how human communities lived. On a geological scale, it is catastrophic, and on an archaeological one as well.

It’s interesting to me that all those massive catastrophes, and there were plenty more, and worse ones than the draining of Lake Missoula, left plenty of archaeological remains of our hunter-gatherer ancestors and their way of life. We find them all over the landscape.

What we don’t find in the archaeological record, are traces of the advanced civilization that Hancock proposes existed during the last ice age. Presumably, those traces would have been more abundant and more durable than those of the hunter gatherers of the time, who lived in small, scattered, low density communities, and who used comparatively simple technology. If Hancock is right, then those catastrophes were incredibly selective in the application of their destructive power. A bit too selective for my liking.

References

Baker VR 2009. The channeled scabland: a retrospective, Annual Review of Earth and Planetary Science, 37: 393-411. https://www.geo.umass.edu/climate/papers2/Baker_retrospective_2009.pdf

Bretz JH. 1923b. The Channeled Scabland of the Columbia Plateau. J. Geol. 31:617–49

Norris, S. L., Garcia-Castellanos, D., Jansen, J. D., Carling, P. A., Margold, M., Woywitka, R. J., & Froese, D. G. (2021). Catastrophic drainage from the northwestern outlet of glacial Lake Agassiz during the Younger Dryas. Geophysical Research Letters, 48, e2021GL093919. https://doi.org/10.1029/2021GL093919