Ancient Rome’s Collapse Is Written into Arctic Ice | Hacker News Reader

Ancient Rome’s Collapse Is Written into Arctic Ice

theatlantic.com

111 pointsdiodorus19 comments

Discussion on HN last week referencing a New York Times article on the same topic: https://news.ycombinator.com/item?id=17072712

Cool analysis inspired by this article, comparing the ice lead data to pre-existing (and independently collected) data on building of temples: http://peterturchin.com/cliodynamica/history-is-a-quantitati...

From eyeballing the second graph we see, that lead production (taken as a proxy for economic activity) spikes shortly after a maximum in temple building, as any virtuous Roman would expect, temple building pleases the gods, who then grant the favor of more economic activity.

It's a seductive idea, that we can see into the past so accurately in such a way. The article suggests weaknesses though that seem to be being brushed under the carpet.

The biggest problem is with the economics and the history rather than the science of measuring lead in ice cores.

The article states:

Yet for all these coins, it remains unclear how Rome managed its money in a modern sense

... and that seems to be a problem because the theory asks us to believe something implausible; that during times of war coin production went down. Everything we know about both modern and ancient governments tells us that rulers routinely inflate their currencies to pay soldiers. During a time of war, when desperation is at its peak and there is a need to win at any cost, furiously minting coins to fund the fight is extremely common.

Yet according to these graphs coin production goes up during times of peace and down during times of war. Really?

The story falls apart in other ways further down the article:

That said, the lead record does not seem to mark a few major events in Roman history. The Plague of Justinian, which may have killed half the population of Europe in 541 and 542 a.d., does not seem to feature prominently in the record

OK, so their entire thesis is that the Roman economy can be measured using lead in ice cores, yet an event that more than decimated the population appears to have had no impact on economic activity at all? Either the measurements are wrong, or the historical understanding of the plague is wrong, or the understanding of what lead in ice cores means historically is wrong. But it's hard to see the theory as presented as anything but implausible when such gaping holes exist in the data.

It gets worse:

Nor does the record encompass the full scope of the Roman coin-minting operation: Many important silver mines sat near Greece and the eastern Mediterranean, and their emissions probably did not make it to Greenland.

So lead in the air can make it from Spain to Greenland, about 2700 miles, but not from Greece to Greenland, a distance of about 3100 miles? They're nearly the same distance apart. Does lead in the air have a magic cutoff beyond which it cannot travel on the wind and if so, why does the article not talk about this?

Finally, the article does note that this new study contradicts an earlier study that concluded the opposite.

This is explained by saying the new study has more data. But this still seems odd to me - it's saying the old study had such bad luck that the ice cores they studied were totally misleading to the extent that they presented the opposite of the truth. How did that happen? Is it really plausible and if so what other studies should be invalidated as a result of not taking enough core samples?

I find myself wondering how much of this article boils down to curve fitting and munging the data to fit what we are sure we "know" about Rome, to create a nice story that doesn't rock any boats.

> So lead in the air can make it from Spain to Greenland, about 2700 miles, but not from Greece to Greenland, a distance of about 3100 miles?

I have no domain knowledge about this, but I assumed the difference was in atmospheric circulation. Happy to be corrected by anyone who knows about this stuff, but I'd have thought there was a relatively clear pathway across open ocean from the Iberian peninsula to Greenland. I'd expect the route from Greece to Iceland to be significantly more chaotic as far as wind is concerned; more land, mountain ranges, and opportunities for rainfall and mixing of currents.

Just to add something, we can make some guesses about the circulation of the ocean and wind currents during Roman times because we know that the Roman Warm Period approximated the climate we enjoy today, for several reasons. For example the locations where date palms are grown and dates harvested. We have at least one account which mentions that date palms can be planted in e.g. Greece but that dates will not fruit there (which is the case today), but that dates can be grown and harvested in Judea, which was not the case between the time of the Roman Empire and today because of the colder climate. Medieval scholars weren't sure what to think of that.

Yet according to these graphs coin production goes up during times of peace and down during times of war. Really?

Well, the republican era wasn't a very peaceful time; Rome was pretty much continuously at war in one way or another for centuries. The late republican crisis was unusual because the roman legions were fighting each other, instead of non-roman forces.

> ... and that seems to be a problem because the theory asks us to believe something implausible; that during times of war coin production went down.

This doesn't really surprise me. Lead production during the first downturn was controlled by the Carthaginians, who were effectively wiped out by the Romans (which is why there was a sharp reduction in lead emissions when the Carthaginian Empire fell, followed by a sharp increase after the Romans restarted lead production).

The second and most severe dip happened during the crisis of the third century, which destroyed Roman trade and kicked off the transition from a quasi-market economy to a feudalist economy.

The Plague of Justinian happened after the western empire had already collapsed. The eastern empire did control some of the Spanish coast around that time, but it's plausible that mining had already been reduced to a minimum, since most of the Spanish mines were located in what (as far as I can tell) were effectively frontier regions.

Documented the economic activity? No, they documented deposits of particles that are claimed to be from the Roman Republic smelters and also which are only the particles that existing weather patterns happened to have lead to being deposited. Talk about derivative. Not even to mention that there is little that would imply that smelting for coin production would implicitly relate to economic activity. Run away inflation or corrupt rulers do not necessarily correlate to economic activity but could very well result in increased smelting just as well as technological advances that require more smelting or buildup of the military could.

A good place to start an article about the fifth century CE is definitely the first century BCE. I was just writing an article about Trump which starts with 1527.

1527 is not at all a bad starting point--the year Ferdinand I became king of Croatia, later to rule as Holy Roman Emperor and contesting the Ottoman Empire, who at that time began their great advance into Europe. Also when the Protestant Reformation began picking up steam, the Sack of Rome, and the death of Niccolò Machiavelli.

And it’s around the discovery of America as well, which would also be useful to explain to an audience 1300 years in the future.

Explaining the settlement of america, the type of people that moved over (which are not just a random sample, but certain religious and social groups), and the slave trade are all important factors for the election of Trump later on.

So, yeah, I agree, for a reader a millenium later, it’d be a great starting point.

> A team of archaeologists, historians, and climate scientists have constructed a history of Rome’s lead pollution, which allows them to approximate Mediterranean economic activity from 1,100 b.c. to 800 a.d.

I think that better explains the broad span of time. Then again, if you were writing for an audience 1300 years in the future with little to no genuine knowledge of our time period (other than popular myth and oral tradition) that probably wouldn't be a bad year to start with, since that's not terribly long after major explorations to the West from Europe (Columbus "discovered" the Bahamas around 1492).

Edit: formatting of the quote

Okay, let me rephrase that: A lot of the territory Rome ruled was conquered in Caesar's lifetime (Gaul, most of their core Asian possessions). Most of Rome's noteworthy cultural achievements happened after Caesar was dead. Caesar laid the groundwork for Augustus's form of government, which would survive in some form for nearly 1500 years. So starting an article about Rome's decline with Caesar is like writing an article about the decline of computer science and starting it with Turing.

This article is interesting. This writer may stay

It's important to contrast this graph --- clear as day and the next best thing to a Roman S&P 500 --- to the nonsense revisionism peddled by a certain camp that's come to dominate academia since the 1970s or so.

This camp, as part of a present-day political project, portrays the past as some kind of peaceful, egalitarian utopia ruined by "capitalism" and "colonization". In this camp's ridiculous woldview, all societies are equally complex, all languages are equally expressive, and cultural and linguistic changes always reflect some kind of peaceful transition instead of a violent upheaval.

Rome never fell, these people say: instead, it just chose to adopt the sustainable economic practices of the peaceful immigrants from the steppe. My eyes cannot roll any harder when I read shit like that.

Fortunately, these people are well on the way to being thoroughly discredited. Populations do change. Catastrophes do happen. War was rampant. Ancient DNA confirms it.

Civilization and order are fragile and worth preserving, and an honest examination of the past and strike the fear of decay into us. It took the world until the 19th century (!) to recover from Rome's collapse in all respects; for us, there will be no recovery at all.

Okay - I think you are just making that up. Are there serious people in historical academia working on some sort of "political project" like that, are are you nutpicking some marginal/fringe off the internet? Can you offer some sort of links describing the name of this academic school, who belonged to it, evidence of their influence, etc? I have a personal interest in history sufficiently deep to doubt you.

Can you name the academics who claim war was not rampant over the last couple thousand years?

Heh. Gradualism vs. Catastrophism all over again.

As for 'no recovery for us' (if by 'us' you mean humanity) a thousand years is a long time. Hopefully, by then, they'll have taken some hard-earned lessons from our completely avoidable bone-headed mistakes. Or ... probably too optimistic. Okay, then, 10,000 years to stop being followers of fatuous fools.

On the bright side, if we use up most of the extractable fossil fuels, there won't be enough left for them to take that path.

Reply on news.ycombinator.com