If you’ve been reading the blog for a while, you’ll have noticed that I’m not a fan of trying to panic people about climate change … catastrophism just isn’t my thing. I certainly don’t deny that climate change happens and I agree that it is happening now, but I’m highly skeptical that human action has more than a minor influence compared to the ups and downs of long-term climate shifts driven by natural forces. Ed West has a thumbnail sketch of just how much the European (and especially English) climate change impacted ordinary people during the Middle Ages:
Chart from the Journal of Quaternary Science Reviews showing Greenland ice core data over the last 10,000 years. At the end of the Minoan Warming came the Bronze Age Collapse, after the Roman Warming came the fall of the western Roman Empire.
The climate is changing, with all that entails, something we’ve known about for several decades now. Among the early proponents of the theory of climate change was mid-century climatologist Hubert Lamb, who spent most of his career at the Met Office and during the course of his studies made a curious historical discovery.
It was once widely believed that climate remained relatively stable over recorded history, civilisational lifespans being too brief to see such grand changes. But while looking into medieval chroniclers, Lamb was struck by the numerous references to vineyards in England, some as far as the midlands. As long as anyone had ever remembered, the country had been too cold to grow wine, except in tiny pockets of Sussex which occasionally produced almost-drinkable white.
William of Malmesbury, living in the 12th century, observed of his native Wiltshire that “in this region the vines are thicker, the grapes more plentiful and their flavour more delightful than in any other part of England. Those who drink this wine do not have to contort their lips because of the sharp and unpleasant taste, indeed it is little inferior to French wine in sweetness.” How could that have been?
Lamb concluded that Europe must have been considerably warmer during the Middle Ages, and in 1965 produced his great study outlining the theory of the Medieval Warm Period; this posited that Europe was at its hottest in the High Middle Ages (1000-1300) and then became unusually cool between 1500 and 1700.
Since then, Lamb’s thesis has been reinforced by analysis of pollen in peat bogs, as well as the radioactive isotope Carbon-14 found in tree rings (the less sun, the more Carbon-14). In Medieval Europe, every summer was a hot girl summer — and tiny changes could make earth-shattering differences.
The people of Europe enjoyed that extended period of warmer weather for about 300 years, then things suddenly got far worse:
Across Europe, people must have noticed a change. Farmers in the Saastal Valley in Switzerland were probably the first to observe what was happening, back in the 1250s, when the Allalin Glacier began to flow down the mountain. Surviving plant material from Iceland suggests an abrupt decrease in the temperature from 1275 — and, as Rosen points out, a reduction of one degree made a harvest failure seven times more likely. From 1308 England saw four cold winters in succession; the Thames froze, chroniclers recalling dogs chasing rabbits across the icy surface for the first time.
As with many things, change was gradual, until it was dramatic, for then came the disastrous year of 1315. The Chronicle of Guillaume de Nangis, written by a monk at the Abbey of Saint-Denis outside Paris, recorded that in April the rains came down hard — and didn’t stop until August.
Drenched and starved of sunlight, the crops failed across Europe. The price of food doubled and then quadrupled. By May 1316, crop production in England was down by up to 85 percent and there was “most savage, atrocious death”, as a chronicler put it. Hopeless townsfolk walked into the countryside, searching for any bits of food; men wandered across the country to work, only to return and find their wives and children dead from starvation. At one point, on the road near St Albans, no food could be found even for the king. Emaciated bodies could be seen floating face down in flooded fields.
The Great Famine killed anywhere between 5-12% of the European population, although some areas, such as Flanders, suffered far worse death rates, losing up to a quarter of their population to hunger.
