Earth has a peculiar way of keeping the accounts of our endeavors in the most hidden places that are even outside of our imaginations. In such example, a group of multidisciplinary scientists decrypted humanity's effects on nature in the last 800 years, and shed light on a medieval era murder — the infamous killing of Thomas Becket.
The ripple effects of the feud between Henry II and Archbishop of Canterbury Thomas Becket were found in the unlikeliest places: in a nearly 72 meters long ice core bored from the Colle Gnifetti glacier of Monte Rosa in the Swiss-Alpine alps.
The scientists were able to see the timeline of Britain’s lead mining industry, with its ups and downs due to the major events during the medieval era.
And, perhaps the most striking revelation that came from the study is that it showed the air pollution from lead in the 12th century was actually as bad then as it was during the industrial revolution.
How did they achieve the results?
The scientists used ultra-high precision laser technology to analyze the ice bored from the heart of the Alpine glacier in 2013. The ice core is highly compacted and contains invisible layers akin to tree trunk rings. These layers have chemical elements that form a chemical fingerprint, and it was seen that it "exactly mapped the comings and goings of England's kings".
Once the ice was analyzed, the researchers compared the physical records from it with the written records of lead and silver production in England. They were a match.
The ice was showing them a year-by-year picture of more than 2,000 years of environmental and political history.
From UK mines to Alp glaciers
It is plausible that a butterfly fluttering its wings could result in a rainstorm in the Amazons. In this case, Henry II would order the killing of Thomas Becket and start the chain of events that would result in the winds of northwest carrying lead — which is a notoriously toxic metal that can reduce brain function and result in lifelong health complications even at low levels of exposure — into the Alps.
Professor Christopher Loveluck from Nottingham University explains the train of events by saying, "In the 1169-70 period, there was a major disagreement between Henry II and Thomas Becket and that clash manifested itself by the church refusing to work with Henry - and you actually see a fall in that production that year."
Henry II would receive backlash from the killing of Becket, and promise to build numerous major monastic institutions in a short notice to redeem himself. Massive amounts of lead were used in the roofing of these new complexes. Henry's atonement would expand the lead production to the extremes.
All of these turmoils were documented in the ice without exception.
Loveluck explains, "We see direct associations between production levels and the workings of government at the time, for example, lead taxation and lead production plummets in the year when a king dies before they are succeeded by another one. This is because medieval governments shut down in the interregnum."
"The ice core shows precisely when one king died, and lead production fell and then rose again with the next monarch. We can see the deaths of King Henry II, Richard Lionheart and King John there in the ancient ice."
Lead pollution goes way back
According to the writers, some of our perceptions about the Industrial Revolution are in need of an update. Professor Loveluck says, "Our results show that the 12th century has the same levels of lead pollution as we see in the mid-17th century and even in 1890, so our notions of atmospheric pollution starting in the industrial revolution are wrong."
Then, the timeline continues. "The ice core shows a rise with lead petrol in the motor car, and a big fall when lead is banned from fuel in the 1970s."
So yes, nature carries the traces of our hopes, mistakes, and disasters, even in the parts of that may seem far-fetched. In light of the study, it wouldn't be wrong to predict that, if the same glacier were to survive a few more centuries, it could present the air pollution decreasing due to coronavirus, just the same.
The study was published in the journal Antiquity.