What Can Medieval Irish Chronicles Tell us About Climate Change?
Medieval Irish scholars: What can’t they do for us? Having already "saved civilization," they’re now providing important insights into how geological activity can cause weather events, expanding our understanding of global climate change. In a paper published by Environmental Research Letters, a team of U.S. and Irish researchers use the Irish Annals — documents of ...
Medieval Irish scholars: What can't they do for us? Having already "saved civilization," they're now providing important insights into how geological activity can cause weather events, expanding our understanding of global climate change.
Medieval Irish scholars: What can’t they do for us? Having already "saved civilization," they’re now providing important insights into how geological activity can cause weather events, expanding our understanding of global climate change.
In a paper published by Environmental Research Letters, a team of U.S. and Irish researchers use the Irish Annals — documents of recorded events written by scribes in Irish monasteries from the fifth to the 17th centuries — as a dataset for the occurence of rare weather events. Specifically, the authors are interested in evidence for the theory that atmospheric ash from volcanic eruptions was responsible for known climate anomalies from the period — in particular the so-called "little ice age."
The Irish accounts are particularly useful because of their descriptive detail and specificity of dates. In total, 83 unique cold events were reported in the Annals, 65 of which were considered reliable.
Here’s one such account from the Annals of Ulster, written in 818:
There was abnormal ice and much snow from the Epiphany to Shrovetide. The Boyne and other rivers were crossed dry-footed; lakes likewise. Herds and hunting-parties were on Loch Neagh,(and) wild deer were hunted. The materials for an oratory were afterwards brought by a large company from the lands of Connacht over Upper and Lower Loch Erne into [Leinster]; and other unusual things were done in the frost and hail.
And from the Annals of Connacht in 1465:
Exceeding great frost and snow and stormy weather this year, so that no herb grew in the ground and no leaf budded on a tree until the feast of St. Brendan, but a man, if he were the stronger, would forcibly carry away the food from the priest in church, even though he had the Sacred Body in his hands and stood clothed in Mass-vestments.
The authors found that 53.6 percent of the identified cold events correspond with known volcanic events, which they say is nearly impossible to attribute to coincidence.
Why does this matter? The authors write that "determining the extent to which human activity drives future climatic variation requires knowledge of past climate, allowing us us to ascertain the boundaries of natural variability and to test the veracity of models preciting future climate." Developing accurate climate records for particular regions can tell us more about how "individuals and societies experience climate and plan for extreme weather." These days we’re more worried about unusual warming than cooling, but the local priests may still want to keep an eye on the kitchen during the Feast of St. Brendan.
Can we get the Irish monks on the eurozone crisis next?
Via National Affairs
Joshua Keating was an associate editor at Foreign Policy. Twitter: @joshuakeating
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