Volcanic Eruptions Linked to Origins of Black Death: New Tree Ring Research Reveals Climate Connection

The study was published in the journal Communications Earth & Environment (Representational)

Recent research has uncovered that previously undocumented volcanic eruptions may have initiated an unexpected chain of events that brought the Black Death, humanity's most devastating pandemic, to medieval European shores.

The bubonic plague outbreak known as the Black Death decimated Europe's population during the mid-14th century, killing tens of millions and eliminating up to 60 percent of inhabitants in certain regions.

Historians and scientists have long debated the plague's European arrival and its unprecedented rapid, massive spread.

Two researchers studying tree ring patterns have proposed that a volcanic eruption might have been the catalyst for this catastrophic sequence.

By examining tree rings from Spain's Pyrenees mountains, they determined that southern Europe experienced unusually cold and wet summers from 1345 to 1347.

When comparing climate data with contemporary written accounts, the researchers demonstrated that temperatures likely decreased due to reduced sunlight following one or more volcanic eruptions in 1345.

This climate shift destroyed harvests, leading to crop failures and the onset of famine.

Martin Bauch, a historian at Germany's Leibniz Institute for the History and Culture of Eastern Europe, explained that powerful Italian city-states had established extensive Mediterranean and Black Sea trade routes, enabling them to activate an efficient system to prevent starvation.

"But ultimately, these would inadvertently lead to a far bigger catastrophe," he noted in a statement.

The city-states of Venice, Genoa, and Pisa arranged grain shipments from the Golden Horde Mongols in central Asia, where the plague is believed to have originated.

Previous studies suggest these grain vessels transported unwanted passengers: rats carrying fleas infected with Yersinia pestis, the bacterium responsible for plague.

Between 25 and 50 million people perished over the subsequent six years.

While the narrative encompasses natural, demographic, economic, and political factors in the region, the researchers argued that the previously unidentified volcanic eruption ultimately paved the way for one of history's greatest disasters.

"Although the coincidence of factors that contributed to the Black Death seems rare, the probability of zoonotic diseases emerging under climate change and translating into pandemics is likely to increase in a globalised world," stated study co-author Ulf Buentgen of Cambridge University.

"This is especially relevant given our recent experiences with Covid-19."

The research was published in the journal Communications Earth & Environment on Thursday.